CN106621773B

CN106621773B - A kind of sintering flue gas ammonia charcoal combined desulfurization and denitration method

Info

Publication number: CN106621773B
Application number: CN201611269710.XA
Authority: CN
Inventors: 朱德庆; 潘建; 郭正启; 李启厚; 李紫云; 梁钟仁
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2016-12-30
Filing date: 2016-12-30
Publication date: 2019-11-26
Anticipated expiration: 2036-12-30
Also published as: CN106621773A

Abstract

The invention discloses a kind of sintering flue gas ammonia charcoal combined desulfurization and denitration methods, and sintering flue gas is after the desulfurization of absorbing liquid containing ammonia again through activated carbon adsorption；Carbonaceous raw material that the active carbon is 2: 1~5: 1 by mass ratio, metal oxide source roasts at 850~1100 DEG C and obtains；The carbonaceous raw material is semicoke, or the mixture for coal and biomass.In the present invention, the active carbon as made from by ammonia and the method for the invention is combined, can effectively desulphurization denitration, additionally aid and reduce secondary pollution, reduction technique, reduction processing cost.

Description

A kind of sintering flue gas ammonia charcoal combined desulfurization and denitration method

Technical field

The invention belongs to the environmental technology fields of sintering gas purifying, and in particular to a kind of activated carbon combined using ammonium hydroxide- The method for removing sulphur and nitre.

Background technique

Steel and iron industry is the important basic industry in China, but is also one of the rich and influential family of industrial pollution, according to " 2012 environment are united Count annual report " it is found that steel industry SO₂Total emission volumn is 2,000,000 tons, accounts for current year whole nation SO₂The 9.4% of total emission volumn；Steel industry NO_XTotal emission volumn is 540,000 tons, accounts for current year whole nation NO_XThe 2.3% of total emission volumn.Sintering is one of the important procedure of steel production, SO in discharged sintering flue gas₂Concentration be generally 80~1050ppm, NO_XConcentration be generally 149~522ppm.Sintering plant SO₂Discharge amount accounts for iron and steel enterprise SO₂40%~60%, NO of total emission volumn_XDischarge amount accounts for iron and steel enterprise NO_XTotal emission volumn 48% or so.Chinese Ministry of Environmental Protection in 2012 and State Administration of Quality Supervision, Inspection and Quarantine promulgate state compulsory standard " steel sintering, pelletizing industrial air pollution object Discharge standard " (GB28662-2012).To SO in steel sintering, pelletizing industrial discharged waste gas in standard₂And NO_XConcentration limit It is made that regulation.Therefore, SO in strict control sintering production technique₂And NO_XDischarge amount is a very urgent task.

Sintering flue gas desulfurization denitration technology mainly divides three classes: flue gas desulfurization, denitrating flue gas and flue gas and desulfurizing and denitrifying skill Art.Wherein, flue gas desulfurization technique mainly includes ammonia-ammonium sulfate method, limestone-gypsum method, activated carbon method, ciculation fluidized bed process and double Alkaline process etc..In the sintering flue gas desulfurization process of Iron and Steel Enterprises in China application, wet desulfurizing process proportion is maximum, Zhan Yingyong Secondly the 63.4% of total amount is semi-dry desulfurizing process, dry desulfurizing process；And in wet desulfurizing process, application amount is most For limestone-gypsum method and ammonia-ammonium sulfate method.Desulfurization method of limestone-gypsum main problem is that by-product gypsum utilizes difficult, stockpiling When easily cause secondary pollution.Ammonia-ammonium sulfate method desulfurization brings secondary dirt the problem is that there are the escape of ammonia and generation aerosol Dye.

Domestic and international sintering flue gas denitration technology is mainly include the following types: selective catalytic reduction (SCR), selectivity is non-urges Change reduction method (SNCR), liquid complexing absorption process, oxidative absorption method, reducing absorping method, plasma method.Selective catalytic reduction It (SCR) is with NH₃Make reducing agent, vanadium tungsten titanium system is catalyst to remove the nitrogen oxides in flue gas, obtained denitration product For N₂And H₂O.But use the technology carry out denitration needed for flue-gas temperature for 350 DEG C or so, and sintering flue gas temperature be 100 ~200 DEG C.Therefore, it is necessary to which sintering flue gas is heated to 350 DEG C or so.Since sintering flue gas amount is big, 1 ton of sinter of every production is about Generate 4000~6000m³Sintering flue gas, therefore heat flue gas huge energy consumption；Dust deposit simultaneously in flue gas is small in catalyst Kong Zhong, the problems such as can making catalyst that blocking occur, be poisoned or inactivate.Oxidative absorption method mainly uses strong oxidizer to aoxidize NO For NO₂, then removed by alkaline absorbent.Next oxidative absorption method can also be used catalyst for NO catalysis oxidation and be NO₂, then absorbed with alkaline absorbent.Liquid-phase reduction absorption process refers to be absorbed in flue gas with lye or dilute nitric acid solution NO_X, then use liquid-phase reduction agent (sulphite, sulfide, thiosulfate, aqueous solution of urea etc.) by the NO in solution_XReduction For N₂.Absorption via Chemical Complexation, which refers to, utilizes liquid complexing absorbent FeSO₄, EDTA-Fe (II) etc. directly react generation with the NO in flue gas Then reaction gained complex compound heating is made it release NO by complex compound, and by NO enriching and recovering.Complexing used in the technique Absorbent higher cost recycles difficulty, and cost of investment is higher.

Sintering flue gas and desulfurizing and denitrifying technology mainly active charcoal method, semi-dry spraying method, ciculation fluidized bed process, MEROS Flue gases purification, plasma desulphurization denitration technology, SNOX flue gases purification and wet-type ammonia simultaneous SO_2 and NO removal technology etc.. Activated carbon method is two moving beds of setting, and one absorbs SO using active carbon₂, another utilizes the catalytic action of active carbon, adds Entering liquefied ammonia makes NO_XIt is reduced to N₂, to achieve the purpose that simultaneous SO_2 and NO removal.Active carbon simultaneous SO_2 and NO removal technique mainly includes SO₂It absorbs, SO₂Desorption and Sulphuric acid three parts.Taiyuan Iron And Steel Co., Ltd and Baosteel Zhanjiang steel are in 450m²It is adopted on sintering machine Desulphurization denitration carried out to flue gas with activated carbon method, for desulfurization degree up to 95% or more, the denitrification rate of single-stage active carbon denitration is only 40% left It is right.Activated carbon method technical maturity, desulfurization degree is high, but active carbon price is relatively high, and investment and operating cost are higher, at high cost Up to 20-25 yuan/ton of sinter, and the denitrification rate of single-stage active carbon is low.The sulfuric acid of by-product is second-rate simultaneously, and belongs to danger Chemical products store transport difficult.MEROS flue gases purification is a kind of dry gas clean technologies, and process flow is main It is sprayed into including desulfurizing agent and active carbon, adjusts reaction temperature, the removing of desulfurization product and dust particles and active carbon and desulfurization The repetition of agent recycles.Be constructed and put into operation using the system for desulfuration and denitration of the technology in Voestalpine Lin Ci steel mill, desulfurization degree up to 90%, Denitrification rate is up to 70%, but the technique invests the disadvantages of high with operating cost there are process system complexity.Wet ammonia process desulfurizing denitration Technology refers mainly to ammonia-ammonium sulfate method desulfurization and combines with the technologies such as oxidative absorption method or Absorption via Chemical Complexation, realizes sintering flue gas simultaneously Desulphurization denitration.System desulfurization degree is up to 90% or more, but denitrification rate only 40% or so.

Presently the most three kinds of mature sintering flue gas desulfurizations, denitrating techniques, such as limestone-gypsum method investment and operating cost Lower but by-product gypsum easily causes secondary pollution, and can only effective desulfurization using difficulty；Ammonia-ammonium sulfate method investment and operation Cost is relatively low, desulfurization degree is high and cost is only 4 yuan/ton of sinters, but there are the escapes of ammonia and formation aerosol to bring secondary dirt Dye, denitrification rate are low (only 30% or so)；When activated carbon desulfurization denitration desulphurization denitration, desulfurization degree need to be distinguished using two absorption towers Height, but liquefied ammonia need to be added, active carbon price is relatively high, and investment and operating cost are higher, and cost is up to 20-25 yuan/ton of burning Mine is tied, while the sulfuric acid of by-product is second-rate, and liquefied ammonia and sulfuric acid belong to dangerous chemical products, stores transport difficult and single-stage Problem existing for denitrating tower denitrification rate low (30-50%) etc..

Summary of the invention

To solve existing for the technical solution of existing sintering flue gas, treatment effect is undesirable, safety is not high, processing cost Greatly and active carbon need to adsorb ammonia in advance, be easy to produce the technical problems such as secondary pollution, the present invention provides a kind of sintering flue gases Ammonia charcoal combined desulfurization and denitration method passes through the activated carbon combined use that ammonium hydroxide-is special, it is intended to reach high-efficiency desulfurization denitration, drop The purpose of low secondary pollution, reduction technique.

A kind of sintering flue gas ammonia charcoal combined desulfurization and denitration method, sintering flue gas is after the desulfurization of absorbing liquid containing ammonia again through active carbon Absorption；Carbonaceous raw material that the active carbon is 2: 1~5: 1 by mass ratio, metal oxide source roasts at 850~1100 DEG C It obtains；The carbonaceous raw material is semicoke, or the mixture for coal and biomass.

In the present invention, active carbon obtained has good mechanical strength, circulation under the quality when maturing temperature Utilization rate is high.The active carbon and ammonium hydroxide are used in combination, desulphurization denitration while realizing sintering flue gas, reduce investment and fortune Row expense eliminates the secondary pollution that sintering flue gas desulfurization denitrification process generates, and solves by-product utilized problem, improves sintering flue gas Desulphurization denitration rate；The transport and storage for avoiding liquefied ammonia and sulfuric acid danger chemical products simultaneously, greatly improve the safety of production Property.Especially in denitrification process, with voluntarily developing to NO_XActive carbon with excellent absorption property can take off at low temperature Nitre, without to desulfurization fume heating can denitration, and without by activated carbon adsorption ammonia, can be greatly lowered in advance operation at This, can also significantly improve denitrification rate.

Absorbing liquid containing ammonia of the present invention be the aqueous solution containing ammonia, preferably ammonium hydroxide, and/or from coking plant contain ammonia Waste water, and/or absorption SO₂The absorbing liquid (that is to say the absorbing liquid comprising ammonium sulfite) of recycled afterwards.

In the present invention, SO will be contained₂Sintering flue gas and the contact of the described absorbing liquid containing ammonia, absorb；The mode of contact is for example It can are as follows: SO will be contained₂Sintering flue gas blast in absorbing liquid containing ammonia, or SO will be contained₂Sintering flue gas in absorption tower with sprinkling The misty contact of absorbing liquid containing ammonia.

In the present invention, absorption there can be SO₂The solution for being converted into ammonium sulfite afterwards is recycled as absorbing liquid；It can be achieved The continuous treatment of flue gas.

The inventors discovered that having SO to absorption₂The pH value of absorbing liquid containing ammonia (present invention also abbreviation absorbing liquid) adjust Control, can the NH that carries of the flue gas after Effective Regulation desulfurization₃Amount, thus more conducively absorption and removing of the active carbon to NOx.

It is found by further investigation, preferably, control absorbs SO₂The pH of absorbing liquid afterwards is 5~7.

The inventors discovered that by absorbing liquid under preferred pH value regulation, be more advantageous to consequent activities charcoal to NOx Absorption, the active carbon can have efficient absorption and removal performance to NOx without additional addition ammonia；In addition, also Conducive to reduction NH₃Escape, effectively avoid secondary pollution.

The study found that absorbing SO₂When absorbing liquid pH value afterwards is lower than 5, acidity enhancing is unfavorable for absorbing liquid to SO₂Suction It receives, and is unfavorable for the volatilization of ammonia, active carbon declines NOx absorbability；When pH value is greater than 7, amount of ammonia slip increases, and leads to sulfurous Sour ammonium concentration decline, causes absorbing liquid to SO₂Absorbability be deteriorated, two kinds of situations cause desulphurizing ability to decline.After desulfurization SO is remained in flue gas₂Increasing concentrations, active carbon is by Preferential adsorption SO₂And then cause denitration performance that can also be declined.

In the present invention, SO can be absorbed by addition alkali compounds regulation₂Absorbing liquid pH value afterwards, adds alkalinity thereto Substance makes the pH value in absorbing liquid in the range.

The alkali compounds can be the aqueous solution of alkali metal hydroxide.

In inventive desulfurization process, in addition to the pH of regulation sweetening process absorbing liquid, to an ammonium hydroxide (water for unit volume flue gas Closing ammonia) (present invention is also referred to as liquid-gas ratio, unit L/m for additive amount, absorbing liquid containing ammonia and flue gas volume ratio³) optimize tune Control can further cooperate with the desulphurization and denitration effect promoted to flue gas.

In the present invention, preferably, absorbing liquid containing ammonia and flue gas volume ratio are 70~120L/m in sweetening process³；It is described The concentration of a hydration ammonia is 0.08~0.43g/L in absorbing liquid containing ammonia.

In the present invention, since absorbing liquid is to SO₂Uptake be it is certain, liquid-gas ratio is smaller, for example, liquid-gas ratio be lower than 70L/m³ When, absorbing liquid is to SO in flue gas₂Uptake it is small, remaining SO in flue gas₂Concentration is higher, and desulphurizing ability is easy to cause to decline.It is de- SO is remained after sulphur in flue gas₂Increasing concentrations, active carbon Preferential adsorption SO₂And then denitration performance is caused also to be declined.But liquid-gas ratio Greater than 120L/m³Afterwards, desulfurization degree increases limited, and cost can obviously rise, and flue gas after desulfurization temperature is relatively low, is unfavorable for activity Charcoal denitration.

In the present invention, pass through the tune of the concentration of a hydration ammonia in the liquid-gas ratio in the sweetening process and absorbing liquid containing ammonia Control, the absorbing liquid containing ammonia that every cubic metre of flue gas can be made to be hydrated 10~30g of ammonia content with one are contacted, are reacted.

The inventors discovered that the additive amount of ammonium hydroxide (a hydration ammonia) is controlled in 10~30g/m on the basis of flue gas volume³ Flue gas；The desulphurization and denitration effect promoted to flue gas can further be cooperateed with.

The study found that when the addition quality of the opposite flue gas of ammonium hydroxide (a hydration ammonia) is lower than the lower limit (10g/m³), contain The ammonia level dissolved in ammonia absorbing liquid will be on the low side, and absorbing liquid pH value is relatively low, to flue gas SO₂Absorbability decline, desulfurization degree become Difference, the ammonia for escaping into denitrating tower are reduced, and denitration effect is also deteriorated.The quality of the opposite flue gas of ammonium hydroxide (a hydration ammonia) is higher than described The upper limit when, the ammonia amount that the flue gas after being desulfurized in absorbing liquid carries escape is excessive, cause the waste of ammonia and cost to increase, And it is easy to bring the secondary pollution of ammonia.

Further preferably, in sweetening process, under the liquid-gas ratio, the concentration of a hydration ammonia in the absorbing liquid containing ammonia Preferably 0.08~0.32g/L；Further preferably 0.14~0.25g/L.

In the present invention, sweetening process can carry out in absorption tower, and sintering flue gas is passed through by the bottom on the absorption tower, on It is contacted during row with the absorbing liquid containing ammonia of absorption tower top spray, the NH in the absorbing liquid containing ammonia₃With the SO in flue gas₂Hair Raw reaction, generates ammonium sulfite-(NH₄)₂SO₃, to achieve the purpose that desulfurization；In addition, the absorption during regulation desulphurization reaction The pH of liquid and the absorbing liquid by circulating pump is pumped to cyclic absorption in the spraying device of tower top, it can be achieved that flue gas serialization Processing, also further promotes SO in flue gas using the ammonium sulfite in absorbing liquid₂Dissolution and absorption, enhance SO₂With NH₃It Between react.By constantly supplementing new waste water or ammonia-containing water into absorbing liquid, (NH can be made₄)₂SO₃Concentration is maintained at suitable In range.After reaching certain density ammonium sulfite solution discharge ammonium sulfate production can be prepared by being passed through air oxidation process Product.

In addition, the temperature for preferably controlling the sintering flue gas is 110~230 DEG C in the present invention.

Flue gas (also referred to as desulfurization fume in the present invention) after the absorption of absorbing liquid containing ammonia is again through work prepared by the present invention Property charcoal absorption and denitration.In the present invention, under the maturing temperature, the collaboration of carbonaceous raw material/metal oxide source mass ratio Active carbon obtained has good absorption property and mechanical performance.

The inventors discovered that the mass ratio and maturing temperature to carbonaceous raw material and metal oxide source regulate and control, help Micropore quantity and pore size in further regulation activity charcoal；The yield of active carbon is further promoted in turn, improvement is made Active carbon absorption property and mechanical strength.

In the present invention, the carbonaceous raw material can be semicoke, or the mixture of coal and biomass.

Preferably, in the present invention, the semicoke can be for existing cheap blocky semicoke, preferred semicoke partial size 5~20mm.

Preferably, the mass ratio of coal and biomass is 1: 1~5: 1 in coal and the mixture of biomass.

In the present invention, the mixture is prepared into after agglomerate and carries out roasting again with the metal oxide source instead It answers.

In the present invention, the preparation process of the mixture agglomerate are as follows: mixed after being crushed coal and biomass respectively, then Again with binder mixing, extrusion forming and obtain.

In the present invention, the biomass is preferably stalk biomass.

In the present invention, the stalk biomass is, for example, cotton stalk, sugarcane stalk etc..

Preferably, the biomass is cotton stalk in the present invention.

Preferably, mixing after coal and biomass are crushed to -0.1mm respectively, then being mixed with binder in the present invention It is pressed into the agglomerate of 8~12mm of Φ afterwards.

Preferably, the binder is pitch.

Preferably, the mass percent that the pitch accounts for the mixture is 2~4%.

In the present invention, a kind of preparation process of preferred mixture agglomerate, coal and the biomass are crushed to- 0.1mm is simultaneously mixed by 1: 1~5: 1 mass ratio, 3% pitch (on the basis of the quality of mixture) is then added again, after mixing It is pressed into the agglomerate of the mixture of 8~12mm of Φ.

In the present invention, the roasting process of active carbon preparation carries out preferably in rotary kiln, can make the semicoke or mixing The agglomerate of material comes into full contact with metal oxide source, promotes charing and activation.

Preferably, the temperature of roasting process is 850~1050 DEG C.

The inventors discovered that charing and priming reaction speed faster, carbonize and activate journey within the scope of the preferred temperature More preferably, compression strength is higher for Du Genggao, active carbon yield and yield, absorption property.If temperature is relatively low, charing and priming reaction speed Degree is slow, and charing is low with activation degree, and active carbon yield and yield, absorption property are poor, mechanical strength decline.It is micro- if temperature is excessively high Hole annexs, and absorption property is deteriorated instead.

Preferably, the metal oxide source is that can carry out reduction reaction with CO and/or C to generate CO₂Metal oxygen Compound and/or ore comprising metal oxide.The CO that reduction reaction generates₂Accelerate charcoal and CO being generated by reacting with charcoal again The activation of charcoal in matter raw material.

Preferably, the metal oxide source is the oxidation of at least one of iron, chromium, manganese, cobalt, nickel, vanadium, titanium metal Object, and/or the ore comprising at least one of the oxide.

In the present invention, the metal oxide source is the oxygen of the oxide of iron, the oxide of chromium, the oxide of manganese, cobalt At least one of compound, the oxide of nickel, the oxide of vanadium, titanyl compound；And/or the oxygen of the iron-containing oxide of packet, chromium The mine of at least one of compound, the oxide of manganese, the oxide of cobalt, the oxide of nickel, the oxide of vanadium, titanyl compound Stone.

Preferably, the metal oxide source is Fe₂O₃、Fe₃O₄, manganese oxide, vanadium oxide, titanium oxide, nickel oxide, At least one ore such as cobalt oxide, chromium oxide.

Further preferably, the metal oxide source is the oxide of iron and/or the ore of the iron-containing oxide of packet.

The inventors discovered that preferred iron oxide and ore it is from a wealth of sources, cheap and be easy to and activity Charcoal separation.

In the present invention, the preferably iron-containing oxide ore of ore of the iron-containing oxide of packet, preferably, described The ore for wrapping iron-containing oxide is magnetic iron ore, bloodstone, ilmenite, vanadium titano-magnetite, ferric manganese ore, chromite, laterite nickel At least one of mine etc..

In the present invention, the metal oxide source can choose the pelletizing of metal oxide source.

Preferably, the partial size of the pelletizing of the metal oxide source is 5~16mm.

In the present invention, facilitate the separation of product of roasting using the pelletizing of the metal oxide source of the preferable particle size.It adopts The partial size of pelletizing is less than the lower limit, for example, by using metal oxide source powder or small particle metal oxide source ball Group, Activated carbon separation is difficult, is easy to cause metal oxide source inclusion content raising in active carbon, purity decline.

For example, the commodity iron ore acid pellet (iron that partial size is 5~16mm can be selected in metal oxide source of the present invention The pelletizing of mine).

Preferably, Iron grade is 64.5% in the ore (present invention also abbreviation iron ore) of the described iron-containing oxide of packet More than.

It is more advantageous to the activation effect of charcoal higher than the iron ore of the Iron grade in the present invention, and metallize material (directly also Former iron) purity is higher, added value is bigger, be more conducive to be recycled.

Preferably, being preheated to 400~900 DEG C before the metal oxide source roasting.

In the present invention, the metal oxide source is preferably preheated to the temperature before roasting under oxidizing atmosphere.

Preferably, the metallization material of roasting by-product preheats under oxidizing atmosphere, then preheating product circulation is applied To roasting process.

The high-temperature flue gas generated from rotary kiln baking can be used in the preheating metal oxide source, or passes through by-product Metallization material in metal simple-substance oxidation heat liberation and heat up, facilitate save energy consumption, and metallize material in metal weight New transition is oxide, has good reproducibility, can accelerate the reduction of metal oxide in charing and activation process, generate More CO₂, and then promote charing and the gasification reaction of carbonaceous raw material.

During metallization material warm-up cycle is applied, the oxidizing atmosphere is the atmosphere comprising oxygen, such as oxygen； Air；It or is oxygen and N₂, inert gas etc. mixed atmosphere.

In the present invention, under the carbonaceous raw material/metal oxide source quality when maturing temperature, at preferred roasting The reason time is 1~4h.

The calcination process time is believed that under the maturing temperature, material is in revolution kiln residence time.It should Time is too short, and charing and activation are insufficient, and active carbon yield and yield, absorption property are poor, and mechanical strength is low.If the overlong time. A large amount of micropores annex, and absorption property is deteriorated instead.

Further preferably, the calcination process time is 1~3h.

It is after the completion of roasting, material is cooling, it is preferably cooled to 100 DEG C or less.

For example, product of roasting is incorporated cooling drums, sprays water outside cooling drums and carry out being cooled to 100 DEG C or less.

Product of roasting after cooling is separated.

Restoring product obtained for metal oxide source is the preferred separation method to have based on magnetic metallic iron For dry type magnetic separation separation.

Separation process can carry out in drum magnetic separator.

The magnetic product (metallization material, wherein mainly elemental metals) of magnetic separation separation is the metallic product of CO reduction (present invention also referred to as metallization material)；Such as restore iron obtained.The non magnetic product of magnetic separation process collection is charcoal obtained Material.

The non magnetic product isolated to magnetic separation carries out screening process, and collection cut size is the product of 5~15mm, as living Property charcoal；Partial size is that -5mm is tailings.

In the present invention, a kind of preferred method that active carbon is prepared using carbonaceous raw material, with semicoke (5 available on the market ~20mm) it is raw material, with commodity iron ore acid pellet (5~16mm of granularity, iron product by preheating (temperature is 400~900 DEG C) 65.5% or more position) mixing, and rotary kiln is added together and is carbonized and is activated；The mass ratio control of semicoke and iron ore acid pellet 2.5: 1~5: 1, rotary kiln temperature is controlled at 850~1100 DEG C system, and control material is 1 hour~3 in kiln residence time Hour；Dry type magnetic separation separation is carried out using drum magnetic separator after being cooled to 100 DEG C or less, obtains magnetic product (metallization material) With two kinds of products of non magnetic product；Then non magnetic product is sieved, obtain activated carbon grain (5~15mm) and tailings (- 5mm)。

The invention also includes active carbon made from the preparation method described in one kind, partial size is 5~15mm, specific surface area 220-310cm²/ g, 520~630mg/g of iodine absorption number, 1210~1380N/cm of compression strength²。

In the present invention, denitrification process can carry out in the absorption tower filled with the active carbon.

It, can be into one by the regulation of temperature, the air speed of denitrification process ratio to flue gas after desulfurization in charcoal adsorption process Step promotes absorption and removal effect of the active carbon to NOx obtained by the present invention.

In the present invention, denitration process can be carried out at a lower temperature.

Preferably, the flue-gas temperature after control desulfurization process is 70-110 DEG C；Air speed ratio is 698/h-1396/h.

It that is to say, in the present invention, in active carbon denitrification process, the temperature of the flue gas after controlling desulfurization process is 70-110 ℃；Air speed ratio is 698/h-1396/h.

The inventors discovered that under the preferred flue-gas temperature and air speed, first flue gas passes through the work in denitrification process Denitrification rate is up to 86% or more after property charcoal bed.

In the present invention, two absorption towers industrially can be used, sintering flue gas enters in first tower, sprays into absorbing liquid containing ammonia (such as ammonia-containing water from coking plant) carries out desulfurization, while being made using the absorbing liquid circulation in absorption tower containing ammonium sulfite With promotion desulfurization；Using the ammonia in absorbing liquid containing ammonia as absorbent, the NH in absorbing liquid that is sprayed in desulfurizing tower₃With flue gas In SO₂It reacts, generates ammonium sulfite-(NH₄)₂SO₃, to achieve the purpose that desulfurization.During desulphurization reaction, it will inhale Receive liquid recycled, it can be achieved that flue gas continuous treatment, further promote cigarette using the ammonium sulfite for including in absorbing liquid SO in gas₂Dissolution and absorption, enhance SO₂With NH₃Between react.By constantly supplementing new ammonium hydroxide into absorbing liquid or containing ammonia Waste water can make (NH₄)₂SO₃Concentration is maintained in suitable range.It can lead to after reaching certain density ammonium sulfite solution discharge It crosses and is passed through air oxidation process and is prepared into ammonium sulfate product.Flue gas after desulfurization enters second absorption tower, in tower described in filling Active carbon, utilize the NH of the appropriate level to escape from first₃Reduction and active carbon to NO_XCharacteristic Adsorption And catalytic action, at a lower temperature by NO_XAnd NH₃It is converted into N₂And H₂O reaches denitration purpose.The nothing in second denitrating tower It needs to ammoniate, without heating the flue gas after desulfurization, using active carbon to NO_XCharacteristic Adsorption, improve denitration effect.A side as a result, Face only needs to fill the absorption tower of active carbon in one, investment and operating cost can be greatly reduced, and without in denitrating tower Additional addition ammonia, reduces operating cost, can also solve secondary pollution problem caused by the escaping of ammonia present in the ammonia process of desulfurization, also without It need to be as simple two-stage active carbon desulfurization denitrating technique output byproduct sulfuric acid.In addition, absorbing liquid of the cooperation to the first absorption tower Physics prepared by the control and the present invention of pH value, chemistry and the superior active carbon of absorption property, to realize sintering flue gas While desulphurization denitration, and increase substantially denitrification rate.

Main processes of the invention: the sintering flue gas that temperature is 110~230 DEG C is from first desulfuration absorbing tower lower part It flows up after in into tower, spray into the ammonia-containing water solution for example from coking plant downwards into tower and is pumped out from the tower bottom The absorbing liquid containing ammonium sulfite, wash sintering flue gas.Utilize the NH in absorbing liquid₃As absorbent, the SO in flue gas is absorbed₂ And chemically react therewith, ammonium sulfite-(NH is generated in the solution₄)₂SO₃, to achieve the purpose that desulfurization.Ammonium sulfite Be conducive to strengthen absorbing liquid to SO in flue gas₂Absorption, thus reinforcing desulfuration.New contain ammonia by supplementing constantly into absorbing liquid Waste water and from tower bottom extraction contain (NH₄)₂SO₃Solution return first absorption tower and from the top of tower penetrating recycled, when The tower bottom solution sulfite ammonium concentration just pumps out from tower and is sent to ammonium sulfate preparation workshop after reaching certain value, can prepare At ammonium sulfate product；Flue gas (temperature is reduced to 70~110 DEG C) after desulfurization goes out from first desulfurizing tower top row, from second denitration Absorb the bottom of the tower enters, and flows up through the active carbon bed filled in tower, is absorbed using the flue gas after desulfurization from first desulfurization The a small amount of NH brought into tower₃And Characteristic Adsorption and the catalytic action of active carbon, by the NO in flue gas_XAnd NH₃It is converted into N₂And water, Reach denitration purpose.PH value by the way that solution in ammonium hydroxide and a small amount of caustic soda first tower of raising is added regulates and controls first to 5~7 NH in tower₃Volatile quantity.Purified flue gas can be discharged directly into atmosphere.A certain amount of poor work is discharged after absorption a period of time Property charcoal, return to second denitrating tower after sending regeneration workshop to carry out regeneration treatment and drying and carry out denitration.Fresh activity charcoal is from second The tower top on a denitration absorption tower is periodically added.

The advantages of invention and good effect

1, compared with full active carbon desulfurization denitrating technique needs the absorption tower of two built-in active carbons, which only uses one Investment and operating cost can be greatly reduced in the absorption tower of built-in active carbon；The technique not by-product sulfuric acid, but sulfuric acid can be produced Ammonium, the production for the chemicals that eliminates danger；The technique adjusts the pH value control of solution in first desulfurizing tower by adding a small amount of caustic soda NH processed₃Volatility, without adding liquefied ammonia or ammonium hydroxide before second denitrating tower, the transport and storage of the chemicals that eliminates danger, Improve the safety and operability of production.And the technique can be mentioned from the denitrification rate of full active carbon desulfurization denitrating technique 40% Height arrives the 86~90% of the technique.

2, compared with ammonia process wet desulfurizing process, the denitrification rate of flue gas is greatly improved, it can be from ammonia desulfurizing process Denitrification rate 30% or so is increased to denitrification rate 86~90% of the invention, and makes full use of the NH brought into desulfurizing tower₃Strengthen Denitration effectively eliminates the escaping of ammonia present in ammonia desulfurizing process and generates aerosol problem, reduces secondary pollution.

3, active carbon is prepared due to using the method for the invention, the active carbon is to NO_XAt low temperature there is characteristic to inhale Attached effect is not necessarily to heat the flue gas after desulfurization in advance before second denitrating tower, can obtain high denitrification rate, can be big It is big to simplify production technology, save energy consumption, reduce operating cost.

4, it after ultrasonic wave+hot water washing, dry regeneration can be used in poor active carbon, returns to denitrating tower and uses, reduce activity Charcoal consumption, improves denitrification rate.

5, eliminate the problem of by-product present in numerous desulfurizing and denitrifying process is difficult to be utilized comprehensively, ammonia charcoal method simultaneously Under the premise of desulphurization denitration, can by-product be used as the ammonium sulfate product of chemical fertilizer.

Detailed description of the invention

Fig. 1 is ammonia charcoal combination method desulfurizing and denitrifying process process of the invention.

Specific embodiment

Benchmark example:

(1) single ammonia process wet desulphurization denitration: in fixed SO₂Concentration is 1500~2100mg/Nm³, NO_XConcentration be 260~ 400mg/Nm³, CO concentration is 8000~13500mg/Nm³, CO₂Concentration is 7~8%, O₂Concentration is 13~14%, remaining carrier gas For N₂, and flue-gas temperature is 110~230 DEG C, flue gas flow 30L/min, liquid-gas ratio is 80L/m in desulfurizing tower³, absorption liquid pH Value is 5~7 (ammonium hydroxide is added to adjust), SO in absorbing liquid₃ ^2-Initial concentration is 0.3mol/L and ammonium hydroxide additive amount is 10g/m³Flue gas Under the conditions of the Benchmark System of (that is to say: every cubic metre of flue gas is hydrated ammonia with 10g mono- and reacts), flue gas ammonia process wet desulphurization has been carried out Denitration experiment, flue gas desulphuization rate reach 89.68%-90.56%, and denitrification rate is 20.32~30.57%.

(2) single-stage conventional activated carbon (commodity of market sale) denitration: in fixed SO₂Concentration is 1500~2100mg/Nm³, NO_XConcentration is 260~400mg/Nm³, CO concentration is 8000~13500mg/Nm³, CO₂Concentration is 7~8%, O₂Concentration be 13~ 14%, remaining carrier gas is N₂, flue-gas temperature is 70~110 DEG C, flue gas flow 30L/min, and ammonium hydroxide additive amount is 10g/m³Flue gas Under the conditions of the Benchmark System of (that is to say: every cubic metre of flue gas is hydrated ammonia with 10g mono- and reacts), sintering flue gas single-stage activity has been carried out The experiment of charcoal desulphurization denitration.When air speed is 698/h (active carbon height reaches 400mm) -1396/h (active carbon bed depth 300mm) When, desulfurization degree is 91.89.%~92.68%, and denitrification rate is 35.53~40.31%.

(3) ammonia process+conventional activated carbon combined desulfurization and denitration: in fixed SO₂Concentration is 1500~2100mg/Nm³, NO_XConcentration For 260~400mg/Nm³, CO concentration is 8000~13500mg/Nm3, and CO2 concentration is 7~8%, O₂Concentration is 13~14%, Over-carriage gas is N₂, and flue-gas temperature is 110~230 DEG C, flue gas flow 30L/min, liquid-gas ratio is 80L/m in desulfurizing tower³, inhale Receiving liquid pH value is 5~7 (ammonium hydroxide is added to adjust), SO in absorbing liquid₃ ^2-Initial concentration is 0.3mol/L and ammonium hydroxide additive amount is 10g/ m³Flue gas (that is to say: every cubic metre of flue gas is hydrated ammonia with 10g mono- and reacts), flue gas after desulfurization temperature are 70~110 DEG C, and air speed is Under the base condition of 698/h (active carbon height reaches 400mm) -1396/h (active carbon bed depth 300mm), ammonia has been carried out Method-conventional activated carbon combined desulfurization and denitration experiment.Desulfurization degree be 93.22.%~94.00%, denitrification rate be 66.46~ 70.31%.

Following embodiment, comparative example, in addition to special statement, using raw materials such as bituminous coal below, stalk, oxides-containing irons:

Carbonaceous raw material used in active carbon preparation is bituminous coal, stalk.Wherein, the fixed carbon content of the butt of bituminous coal is 53.6%, fugitive constituent 35.5%, ash 10.9%；The fixed carbon content of the butt of cotton stalk is 18.5%, fugitive constituent 78.9%, Ash 2.6%；The fixed carbon content of the butt of sugarcane stalk is 14.4%, fugitive constituent 72.6%, ash 2.4%.

The Iron grade of iron ore acid pellet is 64.8%；Partial size is 5~16mm.

Embodiment 1:

Iron ore acid pellet is preheating to 400 DEG C of addition rotary kilns, semicoke (5~20mm) and iron ore acid pellet (5~ 2.5: 1, rotary kiln temperature is controlled at 1050 DEG C for mass ratio control 16mm), and control material is 3 small in kiln residence time When.Obtaining activated carbon product yield is 60.3%, and the degree of metalization for the material that metallizes is 94.3%, Iron grade 89.10%.It is living Property charcoal properties of product are as follows: 5~15mm of partial size accounts for 78.2%, specific surface area 305cm²/ g, Kong Rong 0.247cm³/ g, moisture 0.90%, ash 9.0%, iodine absorption number 620mg/g, compression strength 1300N/cm²。

It is SO to exhaust gas components₂Concentration is 2017mg/Nm³, NO concentration is 396mg/Nm³, CO concentration is 11250mg/Nm³, CO₂Concentration is 7.5%, O₂Concentration be 13% sintering flue gas, flue gas flow be 30L/min, 110 DEG C of flue-gas temperature, first The absorption liquid pH sprayed in absorption tower was 6.8 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, liquid-gas ratio For 80L/m³, a hydration ammonia density of absorbing liquid is 0.125g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under conditions of desulfurization；Flue gas is reduced to 100 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 300mm of the active carbon in tower, corresponding air speed are 1396/h.Under the above conditions, the method Desulfurization degree can reach 98.86%, denitrification rate can reach 87.79%.

Embodiment 2:

The active carbon of the present embodiment is prepared via a method which: iron ore acid pellet is preheating to 900 DEG C of addition rotary kilns, and half 5: 1, rotary kiln temperature is controlled at 900 DEG C the control of the mass ratio of burnt (5~20mm) and iron ore acid pellet (5~16mm), It is 3 hours that material, which is controlled, in kiln residence time.Obtaining activated carbon product yield is 79.0%, the degree of metalization for the material that metallizes It is 92.0%, Iron grade 86.21%.Activated carbon product performance is as follows: 5~15mm of partial size accounts for 79.0%, specific surface area 290cm²/ g, Kong Rong 0.239cm³/ g, moisture 0.8%, ash 9.0%, iodine absorption number 550mg/g, compression strength 1240N/cm²。

It is SO to exhaust gas components₂Concentration is 2017mg/Nm³, NO concentration is 396mg/Nm³, CO concentration is 11250mg/Nm³, CO₂Concentration is 7.5%, O₂Concentration be 13% sintering flue gas, flue gas flow be 30L/min, 110 DEG C of flue-gas temperature, first The absorption liquid pH sprayed in absorption tower was 6.8 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, liquid-gas ratio For 90L/m³, a hydration ammonia density of absorbing liquid is 0.167g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under conditions of desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 300mm of the active carbon in tower, corresponding air speed are 1396/h.Under the above conditions, the method Desulfurization degree can reach 98.75%, denitrification rate can reach 87.20%.

Embodiment 3:

The active carbon of the present embodiment is prepared via a method which: iron ore acid pellet is preheating to 750 DEG C of addition rotary kilns, and half 4.0: 1, rotary kiln temperature is controlled 1050 the control of the mass ratio of burnt (5~20mm) and iron ore acid pellet (5~16mm) DEG C, control material is 1 hour in kiln residence time.Obtaining activated carbon product yield is 72.3%, the metal for the material that metallizes Rate is 94.3%, Iron grade 89.16%.Activated carbon product performance is as follows: 5~15mm of partial size accounts for 79.6%, specific surface area 290cm²/ g, Kong Rong 0.223cm³/ g, moisture 1.0%, ash 8.9%, iodine absorption number 610mg/g, compression strength 1210N/cm²。

It is SO to exhaust gas components₂Concentration is 1720mg/Nm³, NO concentration is 396mg/Nm³, CO concentration is 13500mg/Nm³, CO₂Concentration is 7.5%, O₂Concentration be 13% sintering flue gas, flue gas flow be 30L/min, 180 DEG C of flue-gas temperature, first The absorption liquid pH sprayed in absorption tower was 6.9 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, liquid-gas ratio For 70L/m³, a hydration ammonia density of absorbing liquid is 0.286g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 20g mono-) Under conditions of carry out desulfurization；Flue gas is reduced to 110 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with activity The absorption tower of charcoal carries out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, The desulfurization degree of the method can reach 98.95%, and denitrification rate can reach 89.59%.

Embodiment 4:

To exhaust gas components SO₂Concentration is 1500mg/Nm³, NO concentration is 265mg/Nm³, CO concentration is 8000mg/Nm³, CO₂ Concentration is 7.5%, O₂The sintering flue gas that concentration is 13% is 30L/min in flue gas flow, and 230 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 120L/m³, a hydration ammonia density of absorbing liquid is 0.25g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 30g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 110 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 300mm of the active carbon in tower, corresponding air speed are 1396/h.Under the above conditions, should The desulfurization degree of method can reach 99.66%, and denitrification rate can reach 87.35%.

Embodiment 5:

The active carbon of the present embodiment is prepared via a method which: iron ore acid pellet is preheating to 750 DEG C of addition rotary kilns, and half 5: 1, rotary kiln temperature is controlled at 1050 DEG C the control of the mass ratio of burnt (5~20mm) and iron ore acid pellet (5~16mm), It is 3 hours that material, which is controlled, in kiln residence time.Obtaining activated carbon product yield is 72.3%, the degree of metalization for the material that metallizes It is 94.8%, Iron grade 89.66%.Activated carbon product performance is as follows: 5~15mm of partial size accounts for 85.6%, specific surface area 310cm²/ g, Kong Rong 0.221cm³/ g, moisture 0.8%, ash 8.3%, iodine absorption number 630mg/g, compression strength 1290N/cm²。

It is SO to exhaust gas components₂Concentration is 1720mg/Nm³, NO concentration is 265mg/Nm³, CO concentration is 13500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 13% is 30L/min in flue gas flow, and 230 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 6.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 80L/m³, a hydration ammonia density of absorbing liquid is 0.225g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 18g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 110 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 99.00%, and denitrification rate can reach 90.79%.

Embodiment 6:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.2 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 80L/m³, a hydration ammonia density of absorbing liquid is 0.1875g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 99.50%, and denitrification rate can reach 88.87%.

Embodiment 7:

The active carbon of the present embodiment is prepared via a method which:

Carbonaceous agglomerate is mixed with cotton stalk by 5: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry mass total by bituminous coal and cotton stalk), is pressed into the carbonaceous agglomerate of Φ 8mm after mixing；Again be preheating to 450 DEG C of iron ore acid pellet is added in rotary kiln together, and the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 3: 1；Revolution Kiln temperature is controlled at 1080 DEG C, and control material is 1 hour in kiln residence time.Obtaining activated carbon product yield is 58.1%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 75.0%, moisture 0.90%, ash 12.9%, surface area 350cm²/ g, iodine absorption number 560mg/g, compression strength 1300N/cm².The degree of metalization of metallization material is 94.0%, iron product Position is 88.90%.

It is SO to exhaust gas components₂Concentration is 2017mg/Nm³, NO concentration is 396mg/Nm³, CO concentration is 11250mg/Nm³, CO₂Concentration is 7.5%, O₂Concentration be 13% sintering flue gas, flue gas flow be 30L/min, 110 DEG C of flue-gas temperature, first The absorption liquid pH sprayed in absorption tower was 6.8 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, liquid-gas ratio For 80L/m³, a hydration ammonia density of absorbing liquid is 0.1875g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under conditions of desulfurization；Flue gas is reduced to 80 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 300mm of the active carbon in tower, corresponding air speed are 1396/h.Under the above conditions, the method Desulfurization degree can reach 98.90%, denitrification rate can reach 88.65%.

Embodiment 8:

Carbonaceous agglomerate is mixed with cotton stalk by 4: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and cotton stalk), is pressed into the carbonaceous agglomerate of Φ 8mm after mixing；Again be preheating to 750 DEG C of iron ore acid pellet is added in rotary kiln together, and the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 3: 1；Revolution Kiln temperature is controlled at 1080 DEG C, and control material is 1 hour in kiln residence time.Obtaining activated carbon product yield is 58.6%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 65.4%, moisture 0.90%, ash 12.0%, surface area 390cm²/ g, iodine absorption number 585mg/g, compression strength 1260N/cm².The degree of metalization of metallization material is 93.8%, iron product Position is 88.00%.

It is SO to exhaust gas components₂Concentration is 2017mg/Nm³, NO concentration is 396mg/Nm³, CO concentration is 11250mg/Nm³, CO₂Concentration is 7.5%, O₂Concentration be 13% sintering flue gas, flue gas flow be 30L/min, 110 DEG C of flue-gas temperature, first The absorption liquid pH sprayed in absorption tower was 6.8 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, liquid-gas ratio For 80L/m³, a hydration ammonia density of absorbing liquid is 0.1875g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under conditions of desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 300mm of the active carbon in tower, corresponding air speed are 1396/h.Under the above conditions, the method Desulfurization degree can reach 98.83%, denitrification rate can reach 88.66%.

Embodiment 9:

Carbonaceous agglomerate is mixed with cotton stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and cotton stalk), is pressed into the carbonaceous agglomerate of Φ 8mm after mixing；Again be preheating to 650 DEG C of iron ore acid pellet is added in rotary kiln together, and the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 4: 1；Revolution Kiln temperature is controlled at 1080 DEG C, and control material is 1 hour in kiln residence time.Obtaining activated carbon product yield is 58.3%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 65.0%, moisture 0.90%, ash 12.0%, surface area 420cm²/ g, iodine absorption number 640mg/g, compression strength 1250N/cm².The degree of metalization of metallization material is 93.8%, iron product Position is 88.02%.

It is SO to exhaust gas components₂Concentration is 1720mg/Nm³, NO concentration is 396mg/Nm³, CO concentration is 13500mg/Nm³, CO₂Concentration is 7.5%, O₂Concentration be 13% sintering flue gas, flue gas flow be 30L/min, 180 DEG C of flue-gas temperature, first The absorption liquid pH sprayed in absorption tower was 6.9 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, liquid-gas ratio For 80L/m³, a hydration ammonia density of absorbing liquid is 0.1875g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under conditions of carry out desulfurization；Flue gas is reduced to 70 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with activity The absorption tower of charcoal carries out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, The desulfurization degree of the method can reach 98.89%, and denitrification rate can reach 90.00%.

Embodiment 10:

Carbonaceous agglomerate is mixed with cotton stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and cotton stalk), is pressed into the carbonaceous agglomerate of Φ 8mm after mixing；Again be preheating to 850 DEG C of iron ore acid pellet is added in rotary kiln together, and the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 4: 1；Revolution Kiln temperature is controlled at 1050 DEG C, and control material is 2 hours in kiln residence time.Obtaining activated carbon product yield is 66.3%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 69.3%, moisture 0.82%, ash 12.0%, surface area 410cm²/ g, iodine absorption number 660mg/g, compression strength 1295N/cm².The degree of metalization of metallization material is 94.0%, iron product Position is 89.0%.

To exhaust gas components SO₂Concentration is 1500mg/Nm³, NO concentration is 265mg/Nm³, CO concentration is 8000mg/Nm³, CO₂ Concentration is 7.5%, O₂The sintering flue gas that concentration is 13% is 30L/min in flue gas flow, and 230 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 120L/m³, a hydration ammonia density of absorbing liquid is 0.083g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 110 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 300mm of the active carbon in tower, corresponding air speed are 1396/h.Under the above conditions, should The desulfurization degree of method can reach 99.10%, and denitrification rate can reach 90.11%.

Embodiment 11:

Carbonaceous agglomerate is mixed with sugarcane stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 8mm after mixing；Again be preheating to 750 DEG C of iron ore acid pellet is added in rotary kiln together, and the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 4: 1；Revolution Kiln temperature is controlled at 1050 DEG C, and control material is 2 hours in kiln residence time.Obtaining activated carbon product yield is 66.1%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 65.0%, moisture 0.90%, ash 12.0%, surface area 410cm²/ g, iodine absorption number 620mg/g, compression strength 1255N/cm².The degree of metalization of material is 93.0%, and Iron grade is 88.00%.

It is SO to exhaust gas components₂Concentration is 1720mg/Nm³, NO concentration is 265mg/Nm³, CO concentration is 13500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 13% is 30L/min in flue gas flow, and 230 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 6.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 70L/m³, a hydration ammonia density of absorbing liquid is 0.286g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 20g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 110 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 98.55%, and denitrification rate can reach 89.1%.

Embodiment 12:

Carbonaceous agglomerate is mixed with sugarcane stalk by 2: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 10mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 2: 1；It returns Turn kiln temperature control at 1050 DEG C, control material is 2 hours in kiln residence time.Obtaining activated carbon product yield is 62.3%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 73.0%, moisture 0.88%, ash 9.5%, surface area 425cm²/ g, iodine absorption number 602mg/g, compression strength 1345N/cm².The degree of metalization of metallization material is 93.2%, iron product Position is 89.10%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.2 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 80L/m³, a hydration ammonia density of absorbing liquid is 0.3125g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 25g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 99.00%, and denitrification rate can reach 87.90%.

Embodiment 13:

Carbonaceous agglomerate is mixed with sugarcane stalk by 1: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 12mm after mixing；Again with preheating It is added in rotary kiln together to 450 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 5: 1；It returns Turn kiln temperature control at 1100 DEG C, control material kiln residence time be 1 hour, magnetic separation, sieve metallization material and Active carbon；Wherein, activated carbon product yield is 65.5%, and activated carbon product performance is as follows: 5~12mm of partial size accounts for 68.9%, water Point 0.79%, ash 8.6%, surface area 380cm²/ g, iodine absorption number 570mg/g, compression strength 1330N/cm².Metallize ball The degree of metalization of group is 92.3%, Iron grade 88.32%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is that 0.167g/L (is equivalent to every cubic metre of flue gas to react) cigarette with the hydration ammonia of 15g mono- Desulfurization is carried out under conditions of gas；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with work Property charcoal absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.In above-mentioned condition Under, the desulfurization degree of the method can reach 99.15%, and denitrification rate can reach 88.93%.

Embodiment 14:

It is compared with embodiment 10, difference is, embodiment 12 is roasted obtained metallization material in oxygen atmosphere, 900 After preheating is oxidized to metal oxide at DEG C, it is further used as iron ore acid pellet, recycled.Activated carbon product yield obtained is 64.9%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 72.8%, moisture 0.80%, ash 8.7%, surface area 450cm²/ g, iodine absorption number 710mg/g, compression strength 1300N/cm².The degree of metalization of metallized pellet is 94.0%, iron product Position is 88.87%.

Comparative example 1:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.8 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 70L/m³, a hydration ammonia density of absorbing liquid is 0.286g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 20g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 90.25%, and denitrification rate can reach 76.00%.

Comparative example 2:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 4.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 70L/m³, a hydration ammonia density of absorbing liquid is 0.214g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 84.66%, and denitrification rate can reach 70.00%.

By comparative example 1~2 it is found that the pH value on the first absorption tower is not between 5~7；When pH value is lower than 5, acidity enhancing, no Absorption conducive to absorbing liquid to SO2, is unfavorable for the volatilization and escape of ammonia, and active carbon declines nox adsorption ability；PH value When greater than 7, amount of ammonia slip increases, and causes ammonium sulfite concentration to decline, causes absorbing liquid to SO₂Absorption be deteriorated, two kinds of situations Desulphurizing ability is caused to decline.SO is remained in flue gas after desulfurization₂Increasing concentrations, active carbon Preferential adsorption SO₂And then lead to denitration Can also it be declined.

Comparative example 3:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 60L/m³, a hydration ammonia density of absorbing liquid is the item of 0.25g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Desulfurization is carried out under part；Flue gas is reduced to 130 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, the method Desulfurization degree can reach 70.25%, denitrification rate can reach 68.33%.

Comparative example 4:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 130L/m³, a hydration ammonia density of absorbing liquid is that 0.115g/L (is equivalent to every cubic metre of flue gas to react) item with the hydration ammonia of 15g mono- Desulfurization is carried out under part；Flue gas is reduced to 50 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, the method Desulfurization degree can reach 99.89%, denitrification rate can reach 60.30%.

By comparative example 3~4 it is found that the liquid-gas ratio on the first absorption tower is not in 70~120L/m³When: when liquid-gas ratio is lower than 70L/ m³When, since absorbing liquid is to SO₂Uptake be it is certain, liquid-gas ratio is smaller, and absorbing liquid is to SO in flue gas₂Uptake it is small, flue gas In remaining SO₂Concentration is higher, and desulphurizing ability is caused to decline.SO is remained in flue gas after desulfurization₂Increasing concentrations, active carbon are preferentially inhaled Attached SO₂And then denitration performance is caused also to be declined.But liquid-gas ratio is greater than 120L/m³Afterwards, desulfurization degree increases limited, and cost Can obviously it rise, flue gas after desulfurization temperature is relatively low, is unfavorable for deactivation charcoal denitration.

Comparative example 5:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 130L/m³, a hydration ammonia density of absorbing liquid is 0.076g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 50 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 99.89%, and denitrification rate can reach 66.38%.

Comparative example 6:

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 5.5 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 130L/m³, a hydration ammonia density of absorbing liquid is that 0.038g/L (is equivalent to every cubic metre of flue gas to react) item with the hydration ammonia of 5g mono- Desulfurization is carried out under part；Flue gas is reduced to 50 DEG C by temperature after first absorption tower desulfurization, enters back into second and active carbon is housed Absorption tower carries out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, the method Desulfurization degree can reach 99.88%, denitrification rate can reach 89.37%.

By comparative example 5~6 it is found that ammonium hydroxide additive amount is not 0.08~0.43g/L's in a hydration ammonia density of absorbing liquid When in range, when ammonium hydroxide additive amount is 0.08g/L lower than a hydration ammonia density of absorbing liquid, absorbing liquid pH value is relatively low, to cigarette Gas SO₂Absorbability decline, desulfurization degree are deteriorated, and the ammonia for escaping into denitrating tower is reduced, and denitration effect is deteriorated；Ammonium hydroxide additive amount is big When a hydration ammonia density of absorbing liquid is 0.43g/L, escape amount is excessive, causes secondary pollution, cost increases, and denitrification rate Increasing degree is limited.

Comparative example 7:

Carbonaceous agglomerate is mixed with sugarcane stalk by 1: 2 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 12mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 5: 1；It returns Turn kiln temperature control at 1100 DEG C, control material is 1 hour in kiln residence time.Obtaining activated carbon product yield is 55.6%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 62.0%, moisture 0.77%, ash 8.0%, surface area 220cm²/ g, iodine absorption number 505mg/g, compression strength 1080N/cm².The degree of metalization of metallized pellet is 93.3%, iron product Position is 88.62%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is 0.167g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 15g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 95.16%, denitrification rate 76.45%.

Comparative example 8:

Carbonaceous agglomerate is mixed with cotton stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and cotton stalk), is pressed into the carbonaceous agglomerate of Φ 12mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 7: 1；It returns Turn kiln temperature control at 1080 DEG C, control material is 1 hour in kiln residence time.Obtaining activated carbon product yield is 57.6%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 65.0%, moisture 0.77%, ash 8.0%, surface area 195cm²/ g, iodine absorption number 470mg/g, compression strength 1300N/cm².The degree of metalization of metallized pellet is 95.5%, iron product Position is 88.72%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is 0.111g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 95.86%, denitrification rate 71.67%.

Comparative example 9:

Carbonaceous agglomerate is mixed with sugarcane stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 12mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 4: 1；It returns Turn kiln temperature control at 800 DEG C, control material is 4 hours in kiln residence time.Obtaining activated carbon product yield is 75.6%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 68.0%, moisture 0.77%, ash 12.2%, surface area 170cm²/ g, iodine absorption number 390mg/g, compression strength 990N/cm².The degree of metalization of metallized pellet is 79.5%, Iron grade It is 74.76%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is 0.111g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 96.45%, denitrification rate 65.36%.

Comparative example 10:

Carbonaceous agglomerate is mixed with sugarcane stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 12mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 4: 1；It returns Turn kiln temperature control at 1150 DEG C, control material is 3 hours in kiln residence time.Obtaining activated carbon product yield is 50.6%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 56.0%, moisture 0.70%, ash 14.9%, surface area 120cm²/ g, iodine absorption number 270mg/g, compression strength 1350N/cm².The degree of metalization of metallized pellet is 94.5%, iron product Position is 88.56%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is 0.111g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 95.88%, denitrification rate 55.23%.

Comparative example 11:

Carbonaceous agglomerate is mixed with cotton stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and cotton stalk), is pressed into the carbonaceous agglomerate of Φ 12mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 4: 1；It returns Turn kiln temperature control at 1050 DEG C, control material is 5 hours in kiln residence time.Obtaining activated carbon product yield is 65.6%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 68.0%, moisture 0.77%, ash 15.3%, surface area 180cm²/ g, iodine absorption number 220mg/g, compression strength 1250N/cm².The degree of metalization of metallized pellet is 90.5%, iron product Position is 84.23%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is 0.111g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 95.00%, denitrification rate 61.67%.

Comparative example 12:

Carbonaceous agglomerate is mixed with sugarcane stalk by 3: 1 mass ratio by being crushed to the bituminous coal of -0.1mm respectively, additional 3% Pitch (on the basis of the dry weight total by bituminous coal and sugarcane stalk), is pressed into the carbonaceous agglomerate of Φ 10mm after mixing；Again with preheating It is added in rotary kiln together to 650 DEG C of iron ore acid pellets, the mass ratio of carbonaceous agglomerate and iron ore acid pellet is 1: 1；It returns Turn kiln temperature control at 1050 DEG C, control material is 2 hours in kiln residence time.Obtaining activated carbon product yield is 49.3%, activated carbon product performance is as follows: 5~12mm of partial size accounts for 62.0%, moisture 0.88%, ash 11.5%, surface area 190cm²/ g, iodine absorption number 470mg/g, compression strength 1320N/cm².The degree of metalization of metallization material is 93.2%, iron product Position is 88.65%.

It is SO to exhaust gas components₂Concentration is 1500mg/Nm³, NO concentration is 310mg/Nm³, CO concentration is 11500mg/Nm³, CO₂Concentration is 8%, O₂The sintering flue gas that concentration is 14% is 30L/min in flue gas flow, and 180 DEG C of flue-gas temperature, first is inhaled Receiving the absorption liquid pH sprayed in tower was 7.0 (caustic soda is added to adjust), and sulfite ion initial concentration is 0.3mol/L, and liquid-gas ratio is 90L/m³, a hydration ammonia density of absorbing liquid is 0.111g/L (being equivalent to every cubic metre of flue gas to react with the hydration ammonia of 10g mono-) Under the conditions of carry out desulfurization；Flue gas is reduced to 90 DEG C by temperature after first absorption tower desulfurization, enters back into second equipped with active carbon Absorption tower carry out denitration.Bed depth 400mm of the active carbon in tower, corresponding air speed are 698/h.Under the above conditions, should The desulfurization degree of method can reach 95.10%, denitrification rate 67.21%.

By comparative example 7~12 it is found that the preparation process of the active carbon not activity under the mass ratio and maturing temperature Charcoal quality sharp fall, causes flue gas desulfurization and denitrification effect to be obviously deteriorated.

Claims

1. a kind of sintering flue gas ammonia charcoal combined desulfurization and denitration method, which is characterized in that sintering flue gas is after the desulfurization of absorbing liquid containing ammonia Again through activated carbon adsorption denitration；Carbonaceous raw material that the active carbon is 2: 1 ~ 5: 1 by mass ratio, metal oxide source 850 ~ Roasting obtains at 1100 DEG C；The carbonaceous raw material is semicoke, or the mixture for coal and biomass；

In sweetening process, absorbing liquid containing ammonia and flue gas volume ratio are 70 ~ 120L/m³；A hydration ammonia in the absorbing liquid containing ammonia Concentration is 0.08 ~ 0.43g/L；

Control absorbs SO₂The pH of absorbing liquid afterwards is 5 ~ 7；

In the mixture, the mass ratio of coal and biomass is 1: 1 ~ 5: 1.

2. sintering flue gas ammonia charcoal combined desulfurization and denitration method as described in claim 1, which is characterized in that the metal oxidation Material resource is the oxide of at least one of iron, chromium, manganese, cobalt, nickel, vanadium, titanium metal, and/or includes in the oxide at least one The ore of kind.

3. sintering flue gas ammonia charcoal combined desulfurization and denitration method as claimed in claim 2, which is characterized in that the metal oxidation Material resource is the oxide of iron and/or the ore of the iron-containing oxide of packet；The ore of the described iron-containing oxide of packet be magnetic iron ore, At least one of bloodstone, ilmenite, vanadium titano-magnetite, ferric manganese ore, chromite, lateritic nickel ore.

4. sintering flue gas ammonia charcoal combined desulfurization and denitration method as described in claim 1, which is characterized in that the calcination process time is 1~4h。

5. sintering flue gas ammonia charcoal combined desulfurization and denitration method as described in claim 1, which is characterized in that the metal oxidation 400 ~ 900 DEG C are preheated to before material resource roasting.

6. sintering flue gas ammonia charcoal combined desulfurization and denitration method as claimed in claim 5, which is characterized in that roast the metal of by-product Compound material preheats under oxidizing atmosphere, and preheating product circulation is then applied to roasting process.

7. sintering flue gas ammonia charcoal combined desulfurization and denitration method as described in claim 1, which is characterized in that

The preparation process of the agglomerate of the mixture are as follows: mixed after coal and biomass are crushed to -0.1mm respectively, then with The agglomerate of 8 ~ 12 mm of Φ is pressed into after binder mixing；The biomass is stalk biomass；The binder is drip It is green.

8. sintering flue gas ammonia charcoal combined desulfurization and denitration method as claimed in any one of claims 1 to 7, which is characterized in that active carbon In denitrification process, the temperature of the flue gas after controlling desulfurization process is 70-110 DEG C；Air speed ratio is 698/h -1396/h.