CN107604277A - Processing method, thus obtained pyrolysis furnace nichrome boiler tube and the method for producing ethene of pyrolysis furnace nichrome boiler tube - Google Patents
Processing method, thus obtained pyrolysis furnace nichrome boiler tube and the method for producing ethene of pyrolysis furnace nichrome boiler tube Download PDFInfo
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Abstract
The present invention relates to ethylene production field, and disclosing processing method, thus obtained pyrolysis furnace nichrome boiler tube and the method for producing ethene, this method of pyrolysis furnace nichrome boiler tube includes：Nichrome boiler tube inner surface is cleaned, then under low oxygen partial pressure gas atmosphere, nichrome boiler tube is first warming up to 550 700 DEG C with 55 150 DEG C/h the first programming rate, and it is incubated 5 50 hours, 750 1100 DEG C are warming up to the second programming rate less than 150 DEG C/h again, and is incubated 5 100 hours；Wherein, it is provided with enhanced heat transfer member in the nichrome boiler tube.The method of production ethene includes：Aforementioned processing is carried out with nichrome boiler tube to pyrolysis furnace, then in the obtained pyrolysis furnace of processing with carrying out hydrocarbon vapours cracking reaction in nichrome boiler tube.The pyrolysis furnace nichrome boiler tube for handling to obtain by using the inventive method, it can significantly extend the service cycle of pyrolysis furnace.
Description
Technical field
The present invention relates to ethylene production field, in particular it relates to a kind of processing method of pyrolysis furnace nichrome boiler tube,
Thus obtained pyrolysis furnace nichrome boiler tube and the method for producing ethene.
Background technology
Ethene is one of most important basic material of petroleum chemical industry.The method of production ethene is with pyrolysis in tubular furnace at present
Based on technology, worldwide it is widely applied.A but unavoidable problem in the production process of ethene
Be cracker under arms during coking and carburizing.Coking in cracking process can make boiler tube internal diameter diminish, pipe internal pressure
Drop increase, shorten the cycle of operation of pyrolysis furnace；When tube wall temperature reaches tolerance limit or pressure drop reaches to a certain degree, blowing out is needed
Carry out coke cleaning operation.The coking of boiler tube inwall hinders being normally carried out for cracking reaction, influences yield of ethene, reduces production efficiency, and
And easily promote boiler tube inwall carburizing under high temperature, cause furnace tube material performance to weaken.
At present, it is the elevated temperature strength that ensures ethylene cracking tube, crack furnance radiation section furnace tube is usually nichrome pipe, institute
Mainly it is made up of with material elements such as Fe, Cr, Ni, simultaneously containing trace elements such as Mn, Si, Al, Nb, Ti, W, Mo.Study
Show, at high temperature, Fe, Ni element of tube skin have to coking of the hydrocarbon on FeCrNi alloy cracking furnace pipes surface
There is notable catalytic action.In addition, heavier hydrocarbon raw material in cracking process also along with substantial amounts of Free radical coke and polycondensation
Coking.In the prior art, in order to reduce catalytic coking, researcher attempts to prepare in cracking furnace pipe inner wall surface using multiple technologies
Inert coatings, reduce hydro carbons contact with cracking furnace pipe inner surface Fe, Ni active component.
Canadian NOVA chemical companies disclose a series of cracking furnace pipe inner surfaces that handled under low oxygen partial pressure atmosphere and obtained
The patent application of chromium galaxite oxide-film, including US5630887, US6436202, US6824883, US7156979,
US7488392 etc..Open material shows that the technology illustrates good in the gas pyrolysis furnace using lighter hydrocarbons such as ethane, propane as raw material
Good suppression coking effect, but anti-coking effect is poor in liquid charging stock (such as naphtha) cracking process.Because gas splits
The coking of stove is solved based on catalytic coking, oxide-film can there will be catalytic coking activity Fe, Ni element and hydro carbons knot in boiler tube
Jiao Yuan isolates.And for naphtha, diesel oil etc. for the liquid cracking furnace of raw material for, although its coking is also with catalytic coking
Based on, but Free radical coke and polycondensation coking account for more than the 50% of total coking amount, wherein polycondensation coking can be completely by oxidation
Film covers.Therefore, oxide-film is only effective initial stage in boiler tube military service in liquid cracking furnace pipe, because oxide-film at this moment does not have also
Covered by polycondensation coking, and when pyrolysis furnace runs to the middle and later periods, and oxide-film can not then play it the effect of.
The content of the invention
The invention aims to overcome drawbacks described above of the prior art, there is provided a kind of pyrolysis furnace nichrome stove
The processing method of pipe, thus obtained pyrolysis furnace nichrome boiler tube and the method for producing ethene.
Therefore, to achieve these goals, in a first aspect, the invention provides a kind of pyrolysis furnace nichrome boiler tube
Processing method, this method include：Nichrome boiler tube inner surface is cleaned, then under low oxygen partial pressure gas atmosphere, first
Nichrome boiler tube is warming up to 550-700 DEG C with 55-150 DEG C/h the first programming rate, and is incubated 5-50 hours, then with low
Nichrome boiler tube is warming up to 750-1100 DEG C in 150 DEG C/h the second programming rate, and is incubated 5-100 hours；Wherein, institute
State in nichrome boiler tube and be provided with enhanced heat transfer member.
Second aspect, the invention provides by the pyrolysis furnace that the above method obtains nichrome boiler tube.
The third aspect, the invention provides a kind of method for producing ethene, this method includes：To pyrolysis furnace nichrome
Boiler tube is handled, described then in the obtained pyrolysis furnace of processing with carrying out hydrocarbon vapours cracking reaction in nichrome boiler tube
The method of processing is the processing method of the above-mentioned pyrolysis furnace nichrome boiler tube of the present invention.
The method according to the invention, nichrome boiler tube inner surface is cleaned remain in nichrome to remove first
The cutting fluid of boiler tube inwall, then by carrying out two sections of heating treatments and two sections of isothermal holdings under low oxygen partial pressure gas atmosphere,
The inertia diaphragm with high thermal stability can be formed in the inner surface of nichrome boiler tube, suppress or slow down catalytic coking
Phenomenon, meanwhile, enhanced heat transfer member is internally provided with boiler tube, fluid flow state can be changed, the coefficient of heat conduction is improved, subtracts
Few Free radical coke and polycondensation coking.And no matter the cracking process of gas hydrocarbon raw material or liquid hydrocarbon raw material is respectively provided with
Preferable anti-coking effect (for prior art, can significantly improve the anti-coking in liquid hydrocarbon raw material cracking process
Effect), the service cycle of pyrolysis furnace can be obviously prolonged.
Other features and advantages of the present invention will be described in detail in subsequent specific embodiment part.
Embodiment
The embodiment of the present invention is described in detail below.It is it should be appreciated that described herein specific
Embodiment is merely to illustrate and explain the present invention, and is not intended to limit the invention.
The end points of disclosed scope and any value are not limited to the accurate scope or value herein, these scopes or
Value should be understood to comprising the value close to these scopes or value.For number range, between the endpoint value of each scope, respectively
It can be combined with each other between the endpoint value of individual scope and single point value, and individually between point value and obtain one or more
New number range, these number ranges should be considered as specific open herein.
In a first aspect, the invention provides a kind of pyrolysis furnace processing method of nichrome boiler tube, this method includes：It is right
Nichrome boiler tube inner surface is cleaned the cutting fluid that nichrome boiler tube inwall is remained in removing, then in low oxygen partial pressure
Under gas atmosphere, nichrome boiler tube is first warming up to 550-700 DEG C with 55-150 DEG C/h the first programming rate, and be incubated 5-
50 hours, then nichrome boiler tube is warming up to 750-1100 DEG C with the second programming rate less than 150 DEG C/h, and it is incubated 5-
100 hours；Wherein, it is provided with enhanced heat transfer member in the nichrome boiler tube.
In the present invention, remained in by being cleaned to nichrome boiler tube inner surface with removing in nichrome boiler tube
The cutting fluid of wall and the above-mentioned two sections of heatings carried out under low oxygen partial pressure gas atmosphere and isothermal holding, make low oxygen partial pressure gas
The O of trace in body2It can fully be contacted with tube wall clean after cleaning, make tube wall intact oxidised, the oxide-film covering of formation
Rate is higher, and the oxide-film that such low oxygen partial pressure is formed can give full play to its effect, reduce hydro carbons and cracking furnace pipe inner surface Fe,
The contact of Ni active components, so as to significantly extend the service cycle of pyrolysis furnace.
In the present invention, there is remaining cutting fluid in nichrome boiler tube inner surface in inwall machining process, these
The presence of remaining cutting fluid can be adversely affected, it is necessary in low oxygen partial pressure gas to follow-up low oxygen partial pressure gas atmosphere processing
Atmosphere before processing remains in the cutting fluid of nichrome boiler tube inwall by cleaning to remove.The present invention to nichrome boiler tube
The cleaning method that inner surface is carried out includes any cleaning side for the purpose of cleaning the remaining cutting fluid of nichrome boiler tube inwall
Method, under preferable case, the mode of cleaning is cleaning by degreasing method, it is further preferred that cleaning by degreasing method includes：To nichrome stove
Pipe internal surface carries out ion processing, ungrease treatment, carrying out washing treatment and nitrogen drying processing successively.
For ion processing, there is no particular limitation, as long as the impurity of nichrome boiler tube inner surface can be removed i.e.
Can, such as the impurity such as the sand of nichrome boiler tube inner surface can be rinsed out with running water.
For ungrease treatment, there is no particular limitation, can be various conventional removal greases especially nichrome boiler tube
The method of upper grease, under preferable case, the method for ungrease treatment includes：With degreasing cleaning fluid wash cycles nichrome boiler tube
Inner surface is constant to the pH for cleaning waste liquid；It is further preferred that the condition of wash cycles includes：Temperature is 50-90 DEG C, and the time is
6-12 hours, degreasing are 0.1-1m/s with the flow velocity of cleaning fluid.Wherein, for degreasing, with cleaning fluid, there is no particular limitation, can
Think the conventional various cleaning fluids for being used to remove nichrome boiler tube inner surface residual grease, it can voluntarily be prepared can also
By commercially available.Wherein it is possible to by by neutral cleaners, dispersant, defoamer and surfactant with mass ratio (3-
6)：(0.8-1.2)：1：(0.8-1.2) is mixed to prepare.Neutral cleaners, dispersant, defoamer and surfactant can be distinguished
To remain the conventional various neutral cleaners of cutting fluid with especially removal nichrome boiler tube inner surface except grease, disperseing
Agent, defoamer and surfactant, such as neutral cleaners can be selected from AEO (also referred to as alkyl polyoxyethylene
Ether), at least one of APES and alkanolamine ester fat acid amides, dispersant can be selected from polyoxyethylene alkyl amine,
At least one of sucrose fatty ester and APG (APG for short), defoamer can be selected from higher aliphatic, polyethers and gather
At least one of organosiloxane, surfactant can be selected from fatty glyceride, fatty acid sorbitan and polysorbate
At least one of.For example, neutral cleaners can be selected from the neutral water base degreasers of HJ-W101, OP-10, neutral degreaser agent
At least one of MS0101 and aqueous cleaning agent CLF-700, dispersant can be selected from F460 alkalescents dispersant, dispersant DA
At least one of with dispersant DC, defoamer can be in defoamer GP330, defoaming king FAG470 and SAG470 at least
One kind, surfactant can be selected from low foaming surfactant LT-601, bulb-less surface activity agent 8550 and bubble-free surface activity
At least one of agent 8551.Foregoing various specific neutral cleaners, dispersant, defoamer and surfactants can pass through
It is commercially available.
For carrying out washing treatment, there is no particular limitation, as long as can be by the nichrome boiler tube inner surface after ungrease treatment
Cleaning waste liquid is rinsed well, such as first can be rinsed with running water, is then rinsed with deionized water.
For nitrogen drying processing, there is no particular limitation, as long as can purge nichrome boiler tube inner surface to aneroid
State water, this is well known to those skilled in the art, and will not be repeated here., can also be by boiler tube pipe after nitrogen drying processing
Artificial sealing is carried out at mouthful to avoid the secondary pollution of boiler tube inwall.
In the present invention, low oxygen partial pressure gas atmosphere refers to a kind of reducing atmosphere, and partial pressure of oxygen therein is relatively low, so hair
Raw oxidizing process is very slow, beneficial to the oxide-film that densification is generated in material surface.
The partial pressure of oxygen refers to the pressure shared by oxygen present in atmosphere, under low oxygen partial pressure atmosphere, the oxygen in atmosphere
Gas is essentially from oxygenatedchemicals (such as H2O oxygen caused by) decomposing.
In the present invention, the low oxygen partial pressure gas is preferably water vapour (H2O) and selected from CO2、CO、CH4、C2H6、C3H8、
NH3、H2、N2, at least one of Ar and He admixture of gas；Or it is at least one in water vapour and air or cracking gas
Kind.
Preferably, the percentage by volume that water vapour accounts for low oxygen partial pressure gas is less than 7.5%；It is highly preferred that water vapour accounts for
The percentage by volume of low oxygen partial pressure gas is 2-7.5%, more preferably 2-6%.
As can preferably enumerating for above-mentioned low oxygen partial pressure gas：Water vapour and CH4Admixture of gas, water vapour and CO2's
Admixture of gas, the admixture of gas of water vapour and CO or water vapour and H2Admixture of gas.
In the present invention, it is necessary first to which nichrome boiler tube is warming up to by 550- with 55-150 DEG C/h the first programming rate
700 DEG C, and it is incubated 5-50 hours.Under preferable case, the first programming rate is 55-100 DEG C/h, and soaking time is 5-20 hours.
In the present invention, after above-mentioned first stage heating and insulation is carried out, then with the second heating speed less than 150 DEG C/h
Nichrome boiler tube is warming up to 750-1100 DEG C by degree, and is incubated 5-100 hours；Under preferable case, the second programming rate is 100
DEG C/below h, soaking time is 10-60 hours；It is further preferred that the second programming rate is 30-100 DEG C/h, soaking time is
15-50 hours.When the programming rate being heat-treated in low oxygen partial pressure gas atmosphere processing procedure is 150 DEG C/more than h, due to stove
The heated fast expansion of pipe matrix makes tube skin be hardly formed stable oxide-film, and the oxide-film coverage rate formed compared with
It is low and easily peel off.
After carrying out the cutting fluid that cleaning removes residual to nichrome boiler tube inner surface, in low oxygen partial pressure gas atmosphere
It is lower to carry out two sections of heatings and isothermal holding, and by the control of the condition of above-mentioned heating and insulation within the above range, can be in boiler tube
Inner surface is formed in situ anti-coking, impervious carbon protective film, and not only coverage rate is high, and is firmly combined with boiler tube matrix.
In the present invention, the temperature of nichrome boiler tube second stage heating be preferably 800-1000 DEG C (that is, it is preferred that with
Nichrome boiler tube is warming up to 800-1000 DEG C by the second programming rate).
In the present invention, above-mentioned two sections of heatings and two sections of isothermal holdings are provided with augmentation of heat transfer structure in nichrome boiler tube
Carried out under conditions of part.In low oxygen partial pressure gas atmosphere processing procedure, by being carried out in the presence of the enhanced heat transfer member
Above-mentioned two sections of heatings and two sections of isothermal holdings, change the flow regime of low oxygen partial pressure gas, trace in low oxygen partial pressure gas
O2It can fully be contacted with tube wall, make tube wall intact oxidised, the oxide-film coverage rate of formation is higher；It is in contrast, and right
When boiler tube without enhanced heat transfer member carries out the processing of low oxygen partial pressure gas atmosphere, gas is to be contacted with laminar condition with tube wall,
O among air-flow2Substantially the oxidation reaction of tube wall is not engaged in, tube wall can not be intact oxidised, so the oxide-film formed covers
Lid rate is than relatively low.In addition, by the enhanced heat transfer member, in cracking process, enhanced heat transfer member will be close to tube wall cracking gas
Flow regime after laminar flow becomes turbulent flow, the polycondensation coking of boiler tube inner surface, which is easy to be cleaved airflow scouring, to be fallen, because contracting
Coalescence is burnt usually than more loose coke, weaker in the adhesive force of boiler tube inwall.Therefore, the stove containing enhanced heat transfer member
The coke of inside pipe wall attachment is still based on catalytic coking, and the oxide-film that such low oxygen partial pressure is formed is with regard to that can give full play to its work(
Effect, so as to significantly extend pyrolysis furnace service cycle.
In the present invention, as long as above-mentioned purpose can be reached as above-mentioned enhanced heat transfer member, such as can be to turn round
At least one of knee-piece, inner rib plate and inner fin.
In the present invention, the pyrolysis furnace nichrome boiler tube for being provided with enhanced heat transfer member can be conventional by this area
Method obtain.Formed for example, pyrolysis furnace is cast with nichrome boiler tube generally use spun casting mode, and with strong in pipe
The boiler tube for changing heat transfer member then has different form processings, such as：Boiler tube with twisted sheet or inner fin component in pipe is usual
Obtained using static casting mode block cast；And the boiler tube with internal-rib sheet element is by boiler tube interior welds fin shape in managing
Into.According to the length of boiler tube and the difference of caliber equal-specification, enhanced heat transfer member pipe can be distributed in whole stove with a determining deviation
The different tube sides of pipe.
In addition, the pyrolysis furnace nichrome boiler tube for being provided with enhanced heat transfer member can also be commercially available, such as
The plum tube (to be provided with the pipe of inner fin in pipe) of Kellogg companies, Kubota MERT are managed (to be provided with inner rib plate in pipe
Pipe) and Sinopec twisted slice tube (to be provided with the pipe of twisted sheet in pipe) etc..
In the present invention, boiler tube matrix can use the common nichrome boiler tube of prior art, such as with nichrome stove
On the basis of the weight of pipe, the matrix composition of the nichrome boiler tube can include：Chromium 12-50wt%, nickel 20-50wt%, manganese
0.2-3wt%, silicon 0-3wt%, carbon 0-0.75wt%, 0-5wt% trace element and trace element, surplus is iron；It is described micro-
Secondary element is the one or more in niobium, molybdenum, titanium, tungsten, aluminium, zirconium and rare earth element, and the trace element is sulphur and/or phosphorus.
In the present invention, under above-mentioned treatment conditions, can obtain thickness is that 1-10 μm of (being preferably 6-8 μm), coverage rate are
The oxide-film of more than 85% (being preferably more than 90%).
Second aspect, the invention provides by the pyrolysis furnace that the above method obtains nichrome boiler tube.
From preceding, pyrolysis furnace of the invention with the inner surface of nichrome boiler tube formed with thickness be 1-10 μm (preferably
For 6-8 μm), the oxide-film that coverage rate is more than 85% (is preferably more than 90%).
The third aspect, the invention provides a kind of method for producing ethene, this method includes：To pyrolysis furnace nichrome
Boiler tube is handled, described then in the obtained pyrolysis furnace of processing with carrying out hydrocarbon vapours cracking reaction in nichrome boiler tube
The method of processing is the processing method of the above-mentioned pyrolysis furnace nichrome boiler tube of the present invention.
In the present invention, for hydrocarbon raw material, there is no particular limitation, can be that carburet hydrogen class raw material or liquid hydrocarbon are former
Material；For gas hydrocarbon raw material and liquid hydrocarbon raw material, there is no particular limitation, can be respectively that ethene preparation field is commonly used
Various gas hydrocarbon raw materials and liquid hydrocarbon raw material, it is preferable that gas hydrocarbon raw material be ethane, propane, butane and liquefaction stone
At least one of oil gas；Liquid hydrocarbon raw material is at least one of naphtha, condensate, hydrocracking tail oil and diesel oil.
It is anti-with hydrocarbon vapours cracking is carried out in nichrome boiler tube in the pyrolysis furnace after preceding method of the present invention processing
Should, it is (more existing no matter preferable anti-coking effect to be respectively provided with to the cracking process of gas hydrocarbon raw material or liquid hydrocarbon raw material
For technology, the anti-coking effect in liquid hydrocarbon raw material cracking process can be significantly improved), and cracking can be obviously prolonged
The service cycle of stove.
In the present invention, for the condition of hydrocarbon vapours cracking reaction, there is no particular limitation, can be commonly used in the art
Various conditions, such as can include for liquid hydrocarbon raw material, the condition of cracking reaction：Coil outlet temperature is 780-890
DEG C, coil outlet pressure is 0.1-0.5MPa, and water-oil factor (mass ratio of vapor and liquid hydrocarbon raw material) is 0.3-1.
Embodiment
The present invention will be described in detail by way of examples below.In following examples and comparative example, such as nothing is especially said
Bright, method therefor is method commonly used in the art, and each material used is commercially available.
Preparation example 1
By the neutral water base degreasers (being purchased from Hui Jie articless for washing Co., Ltd of Shenzhen, similarly hereinafter) of HJ-W101, dispersant DA
(being purchased from Dongguan City Ke Ruida Chemical Industry Science Co., Ltd, similarly hereinafter), defoamer GP330 (Jiangsu Hai'an Petrochemical Plant is purchased from,
Similarly hereinafter) and bulb-less surface activity agent 8551 (being purchased from Shanghai Boyihe Chemical Industry Co., Ltd., similarly hereinafter) is according to mass ratio 5：1：1：1 is mixed
Close, obtain degreasing cleaning fluid A1.
Preparation example 2
By HJ-W101 neutral water base degreaser, dispersant DA, defoamer GP330 and bulb-less surface activity agent 8551 according to
Mass ratio 3：0.8：1：1 mixing, obtains degreasing cleaning fluid A2.
Preparation example 3
By HJ-W101 neutral water base degreaser, dispersant DA, defoamer GP330 and bulb-less surface activity agent 8551 according to
Mass ratio 6：1.2：1：1 mixing, obtains degreasing cleaning fluid A3.
Embodiment 1
(1) use cleaning by degreasing method to furnace tube material for 35Cr45Ni industrial crack furnace radiant coil inner surface and put
The same material print in boiler tube is put to be cleaned to remove the cutting fluid remained on nichrome boiler tube inwall and print, clearly
Washing method includes：First boiler tube inner surface is rinsed with running water and print surface is cleaned, then used at 65 DEG C with degreasing clear
Washing lotion A1 is with 0.6m/s flow velocity wash cycles boiler tube inner surface and print surface 9 hours, the pH of the cleaning waste liquid now obtained
Constant, then priority running water and deionized water cleaning oven pipe internal surface and print surface, are finally dried up in boiler tube with nitrogen
Surface and print surface exist to without aqueous water.Wherein, the element composition of Tube alloys is：Cr：33.62、Ni：42.62、Fe：
19.80、Mn：0.95、Si：1.52、Nb:0.72、C：0.48、Ti：0.1st, other：0.19 (wt%).
(2) it is to be placed with same material sample in 35Cr45Ni and boiler tube to furnace tube material after cleaning removes the cutting fluid of residual
The industrial crack furnace radiant coil of piece carries out low oxygen partial pressure gas atmosphere processing.With mutual in crack furnance radiation section furnace tube
Every form, the axially disposed twisted sheet being made into integration with boiler tube, the axial length that twisted sheet distorts 180 ° is a pitch, two
The distance between individual adjacent twisted sheet is 15 pitches.Used low oxygen partial pressure gas is H2With the gas mixing of water vapour
The percentage by volume that thing, wherein water vapour account for low oxygen partial pressure gas is 5.0%, heat-treatment furnace in low oxygen partial pressure gas treating process
Heating be carried out in two steps, after being warming up to 650 DEG C of the first treatment temperature first with 80 DEG C/h programming rate, protect at such a temperature
Temperature 10 hours, 900 DEG C of second processing temperature is then warming up to 50 DEG C/h programming rate again, and insulation 40 is small at such a temperature
When, furnace temperature is then down to room temperature naturally.After cooling, the print placed in boiler tube is taken out, with ESEM and energy disperse spectroscopy point
Its surface composition is analysed, analysis shows form the oxide-film of the oxide comprising Cr, Mn, Ni, Fe and Si element on print surface,
Wherein, the thickness of oxide-film is 7.5 μm, coverage rate 93%.
Hydrocarbon vapours cracking reaction is carried out in industrial pyrolysis furnace after the processing of low oxygen partial pressure gas atmosphere, cracking stock is
Naphtha, its physical property are：32.3~172.5 DEG C of boiling range, proportion D200.7087g/ml；Cracking condition includes：Coil outlet temperature
825 DEG C, water-oil factor 0.55.The cycle of operation of pyrolysis furnace reaches 190 days.
Embodiment 2
According to the method for embodiment 1, the difference is that, in step (1), cleaning method includes：First boiler tube is rinsed with running water
Inner surface and print surface are cleaned, then at 50 DEG C with degreasing cleaning fluid A2 with 1m/s flow velocity wash cycles boiler tube
Inner surface and print surface 7.5 hours, the pH of the cleaning waste liquid now obtained is constant, then priority running water and deionized water
Cleaning oven pipe internal surface and print surface, finally dry up boiler tube inner surface and print surface with nitrogen and exist to without aqueous water.
In step (2), used low oxygen partial pressure gas is H2With the admixture of gas of water vapour, wherein water vapour accounts for low
The percentage by volume of partial pressure of oxygen gas is 2.2%, in low oxygen partial pressure gas treating process the heating of heat-treatment furnace be carried out in two steps,
After being warming up to 600 DEG C of the first treatment temperature first with 60 DEG C/h programming rate, at such a temperature be incubated 15 hours, then again with
40 DEG C/h programming rate is warming up to 850 DEG C of second processing temperature, and is incubated 45 hours at such a temperature, then that furnace temperature is natural
It is down to room temperature.With ESEM and energy spectrometer analysis print surface composition, analysis shows formd on print surface comprising Cr,
The oxide-film of the oxide of Mn, Ni, Fe and Si element, wherein, the thickness of oxide-film is 7.1 μm, coverage rate 90%.
Hydrocarbon vapours cracking reaction is carried out in industrial pyrolysis furnace after the processing of low oxygen partial pressure atmosphere, cracking stock is hydrogenation
Cracking tail oil, its physical property are：171.1~343.2 DEG C of boiling range, proportion D200.8237g/ml, cracking condition include：Coil outlet
805 DEG C of temperature, water-oil factor 0.75.The cycle of operation of pyrolysis furnace reaches 130 days.
Embodiment 3
According to the method for embodiment 1, the difference is that, in step (1), cleaning method includes：First boiler tube is rinsed with running water
Inner surface and print surface are cleaned, then at 90 DEG C with degreasing cleaning fluid A3 with 0.1m/s flow velocity circulation cleaning prepurging
Pipe internal surface and print surface 11 hours, the pH of the cleaning waste liquid now obtained is constant, then priority running water and deionization
Water cleaning oven pipe internal surface and print surface, finally dry up boiler tube inner surface and print surface with nitrogen and exist to without aqueous water.
In step (2), used low oxygen partial pressure gas is H2With the admixture of gas of water vapour, wherein water vapour accounts for low
The percentage by volume of partial pressure of oxygen gas is 5.8%, in low oxygen partial pressure gas treating process the heating of heat-treatment furnace be carried out in two steps,
After being warming up to 700 DEG C of the first treatment temperature first with 100 DEG C/h programming rate, at such a temperature be incubated 5 hours, then again with
100 DEG C/h programming rate is warming up to 950 DEG C of second processing temperature, and is incubated 30 hours at such a temperature, then by furnace temperature certainly
So it is down to room temperature.With ESEM and energy spectrometer analysis print surface composition, analysis shows formd on print surface comprising Cr,
The oxide-film of the oxide of Mn, Ni, Fe and Si element, wherein, the thickness of oxide-film is 7.0 μm, coverage rate 91%.
Hydrocarbon vapours cracking reaction is carried out in industrial pyrolysis furnace after the processing of low oxygen partial pressure gas atmosphere, cracking stock is
Diesel oil, its physical property are：209.3~409.5 DEG C of boiling range, proportion D200.8656g/ml, cracking condition include：Coil outlet temperature
795 DEG C, water-oil factor 0.75.The cycle of operation of pyrolysis furnace reaches 120 days.
Embodiment 4
(1) HK40 lab scale boiler tube inner surfaces and the same material print being placed in boiler tube are carried out using cleaning by degreasing method clear
The cutting fluid that boiler tube inwall and print surface are remained in removing is washed, cleaning method includes：First table in boiler tube is rinsed with running water
Face and print surface are cleaned, then at 60 DEG C with degreasing cleaning fluid A1 with 0.6m/s flow velocity wash cycles boiler tube
Surface and print surface 10 hours, the pH of the cleaning waste liquid now obtained is constant, and then priority running water and deionized water are clear
Prepurging pipe internal surface and print surface, finally dry up boiler tube inner surface and print surface with nitrogen and exist to without aqueous water.Wherein,
The element of Tube alloys forms：Cr：25.3、Ni：20.5、Mn：0.99、Si：0.51、C：0.41st, p ＜ 0.03, S ＜ 0.03,
Surplus is Fe (wt%).
(2) after cleaning removes the cutting fluid of residual, to containing the HK40 that same material print is placed with 1 section MERT pipes and pipe
Lab scale boiler tube carries out low oxygen partial pressure gas atmosphere processing.Using CH4Admixture of gas with water vapour is as low oxygen partial pressure atmosphere
The percentage by volume that processing gas, wherein water vapour account for low oxygen partial pressure gas is 4.5%, and the flow velocity of low oxygen partial pressure gas is
400ml/min, the heating of heat-treatment furnace are carried out in two steps, and are warming up to the first treatment temperature first with 55 DEG C/h programming rate
After 550 DEG C, handle 20 hours at such a temperature, 800 DEG C of second processing temperature be then warming up to 50 DEG C/h programming rate again,
And handle 20 hours at such a temperature, furnace temperature is then down to room temperature naturally.After cooling, the print placed in boiler tube is taken out,
With ESEM and energy spectrometer analysis print surface composition, analysis shows formd on print surface comprising Cr, Mn, Ni, Fe and
The oxide-film of the oxide of Si elements, wherein, the thickness of oxide-film is 7.1 μm, coverage rate 90%.
Hydrocarbon vapours cracking reaction is carried out in lab scale boiler tube after the processing of low oxygen partial pressure atmosphere, cracking stock is stone brain
Oil, its physical property are：32.8~173.8 DEG C of boiling range, proportion D200.7058g/ml；Cracking condition includes：Cracking temperature is 845 DEG C,
Water-oil factor is 0.5.The coking amount of boiler tube (is not carried out clear than prior art without enhanced heat transfer member and without any processing
Wash and low oxygen partial pressure gas atmosphere processing) HK40 boiler tubes coking amount reduce 65.23%.
Embodiment 5
(1) 35Cr45Ni lab scale boiler tube inner surfaces and the same material print being placed in boiler tube are entered using cleaning by degreasing method
Row cleaning remains in the cutting fluid of boiler tube inwall and print surface to remove, and cleaning method includes：First boiler tube is rinsed with running water
Inner surface and print surface are cleaned, then at 85 DEG C with degreasing cleaning fluid A1 with 0.7m/s flow velocity circulation cleaning prepurging
Pipe internal surface and print surface 7 hours, the pH of the cleaning waste liquid now obtained is constant, then priority running water and deionized water
Cleaning oven pipe internal surface and print surface, finally dry up boiler tube inner surface and print surface with nitrogen and exist to without aqueous water.Its
In, the element composition of Tube alloys is：Cr：33.6、Ni：43.7、Mn：0.92、Si：1.23、C：0.49、Fe:18.08, other：
1.98 (wt%).
(2) after cleaning removes the cutting fluid of residual, same material print is placed with to being saved containing 1 in inner rib plate pipe and pipe
35Cr45Ni lab scales boiler tube carries out low oxygen partial pressure pre-oxidation treatment.Using the admixture of gas of CO and water vapour as low oxygen partial pressure
The percentage by volume that atmosphere processing gas, wherein water vapour account for low oxygen partial pressure gas is 5.5%, and the flow velocity of low oxygen partial pressure gas is
450ml/min, the heating of heat-treatment furnace are carried out in two steps, and are warming up to the first treatment temperature first with 70 DEG C/h programming rate
After 650 DEG C, handle 10 hours at such a temperature, 950 DEG C of second processing temperature be then warming up to 30 DEG C/h programming rate again,
And handle 20 hours at such a temperature, furnace temperature is then down to room temperature naturally.After cooling, the print placed in boiler tube is taken out,
With ESEM and energy spectrometer analysis print surface composition, analysis shows formd on print surface comprising Cr, Mn, Ni, Fe and
The oxide-film of the oxide of Si elements, wherein, the thickness of oxide-film is 7.8 μm, coverage rate 91%.
Hydrocarbon vapours cracking reaction is carried out in lab scale boiler tube after the processing of low oxygen partial pressure atmosphere, cracking stock is stone brain
Oil, its physical property are：32.8~173.8 DEG C of boiling range, proportion D200.7058g/ml；Cracking condition includes：Cracking temperature is 845 DEG C,
Water-oil factor is 0.5.The coking amount of boiler tube (is not carried out clear than prior art without enhanced heat transfer member and without any processing
Wash and low oxygen partial pressure gas atmosphere processing) 35Cr45Ni boiler tubes coking amount reduce 75.33%.
Comparative example 1
According to the method for embodiment 1, unlike, be free of twisted sheet in radiant coil, and not to boiler tube inner surface with
Same material print is cleaned, and does not also carry out low oxygen partial pressure gas atmosphere processing.The cycle of operation of pyrolysis furnace is 50 days.
Comparative example 2
According to the method for embodiment 2, unlike, be free of twisted sheet in radiant coil, and not to boiler tube inner surface with
Same material print is cleaned, and does not also carry out low oxygen partial pressure gas atmosphere processing.The cycle of operation of pyrolysis furnace is 45 days.
Comparative example 3
According to the method for embodiment 3, unlike, be free of twisted sheet in radiant coil, and not to boiler tube inner surface with
Same material print is cleaned, and does not also carry out low oxygen partial pressure gas atmosphere processing.The cycle of operation of pyrolysis furnace is 30 days.
Comparative example 4
According to the method for embodiment 1, the difference is that, boiler tube inner surface and same material print are not cleaned, also do not entered
The processing of row low oxygen partial pressure gas atmosphere.The cycle of operation of pyrolysis furnace is 100 days.
Comparative example 5
According to the method for embodiment 2, the difference is that, boiler tube inner surface and same material print are not cleaned, also do not entered
The processing of row low oxygen partial pressure gas atmosphere, the cycle of operation of pyrolysis furnace is 75 days.
Comparative example 6
Carried out according to the method for embodiment 3, unlike, boiler tube inner surface and same material print are not cleaned,
Low oxygen partial pressure gas atmosphere processing is not carried out, and the cycle of operation of pyrolysis furnace is 55 days.
Comparative example 7
According to the method for embodiment 4, the difference is that, HK40 lab scale boiler tube inner surfaces and same material print are not carried out clear
Wash.
With ESEM and energy spectrometer analysis print surface composition, analysis shows print form comprising Cr, Mn, Ni,
The oxide-film of the oxide of Fe and Si elements, wherein, the thickness of oxide-film is 2.7 μm, coverage rate 33%.
Hydrocarbon vapours cracking reaction is carried out in lab scale boiler tube after the processing of low oxygen partial pressure atmosphere, cracking stock is stone brain
Oil, its physical property are：32.8~173.8 DEG C of boiling range, proportion D200.7058g/ml；Cracking condition includes：Cracking temperature is 845 DEG C,
Water-oil factor is 0.5.The coking amount of boiler tube (is not carried out clear than prior art without enhanced heat transfer member and without any processing
Wash and low oxygen partial pressure gas atmosphere processing) HK40 boiler tubes coking amount reduce 16.28%.
Comparative example 8
According to the method for embodiment 5, the difference is that, 35Cr45Ni lab scale boiler tube inner surfaces and same material print are not carried out
Cleaning.
With ESEM and energy spectrometer analysis print surface composition, analysis shows print form comprising Cr, Mn, Ni,
The oxide-film of the oxide of Fe and Si elements, wherein, the thickness of oxide-film is 2.9 μm, coverage rate 35%.
Hydrocarbon vapours cracking reaction is carried out in lab scale boiler tube after the processing of low oxygen partial pressure atmosphere, cracking stock is stone brain
Oil, its physical property are：32.8~173.8 DEG C of boiling range, proportion D200.7058g/ml；Cracking condition includes：Cracking temperature is 845 DEG C,
Water-oil factor is 0.5.The coking amount of boiler tube (is not carried out clear than prior art without enhanced heat transfer member and without any processing
Wash and low oxygen partial pressure gas atmosphere processing) 35Cr45Ni boiler tubes coking amount reduce 17.49%.
Comparative example 9
According to the method for embodiment 4, the difference is that, HK40 lab scale boiler tube inner surfaces and same material print are cleaned
Afterwards, (two sections of heatings and two sections of isothermal holdings) are handled without low oxygen partial pressure gas atmosphere, carries out hydro carbons steaming under the same conditions
Vapour cracking reaction, the coking amount of boiler tube (are not carried out clear than prior art without enhanced heat transfer member and without any processing
Wash and low oxygen partial pressure gas atmosphere processing) HK40 boiler tubes coking amount reduce 6.45%.
Comparative example 10
According to the method for embodiment 1, the difference is that, second processing temperature 900 is warming up to 155 DEG C/h programming rate
DEG C, and it is incubated 40 hours at such a temperature.With ESEM and energy spectrometer analysis print surface composition, analysis shows print surface
Oxide-film coverage rate is less than 30%, and the oxide-film that print surface is formed easily peels off.
By above-described embodiment and comparative example, obtained boiler tube is handled by the method for the present invention, can be in it
Surface forms the moderate oxide-film of thickness, and coverage rate is also high.When the boiler tube that the processing is obtained is used for pyrolysis furnace, pyrolysis furnace fortune
The turn-week phase significantly extends.
Specifically, embodiment 1 and comparative example 1, embodiment 2 and comparative example 2, embodiment 3 and comparative example 3 are relatively understood,
Enhanced heat transfer member is provided with nichrome boiler tube, boiler tube inner surface is cleaned boiler tube inwall is remained in remove and cuts
Liquid is cut, and carries out low oxygen partial pressure gas atmosphere processing, the service cycle of pyrolysis furnace can be obviously prolonged.
Embodiment 1 and comparative example 4, embodiment 2 and comparative example 5, embodiment 3 and comparative example 6 are relatively understood, in boiler tube
The cutting fluid that boiler tube inwall is remained in removing is cleaned on surface, and carries out low oxygen partial pressure gas atmosphere processing (two sections of heatings
With two sections of isothermal holdings), the service cycle of pyrolysis furnace can be obviously prolonged.
Embodiment 4 and comparative example 7, comparative example 9 are compared, embodiment 5 and comparative example 8 relatively understood, to table in boiler tube
Face carries out cleaning removing and remained in after the cutting fluid of boiler tube inwall, carries out low oxygen partial pressure gas atmosphere processing, can substantially carry
The high anti-coking effect in liquid hydrocarbon raw material cracking process.
Embodiment 1 and comparative example 10 are relatively understood, heated up with the second programming rate less than 150 DEG C/h, can
Stable oxide-film is formed in tube skin, and the oxide-film coverage rate formed is higher and is not easy to peel off, with boiler tube matrix knot
Close firm.
The preferred embodiment of the present invention described in detail above, still, the present invention are not limited in above-mentioned embodiment
Detail, in the range of the technology design of the present invention, a variety of simple variants can be carried out to technical scheme, this
A little simple variants belong to protection scope of the present invention.
It is further to note that each particular technique feature described in above-mentioned embodiment, in not lance
In the case of shield, can be combined by any suitable means, in order to avoid unnecessary repetition, the present invention to it is various can
The combination of energy no longer separately illustrates.
In addition, various embodiments of the present invention can be combined randomly, as long as it is without prejudice to originally
The thought of invention, it should equally be considered as content disclosed in this invention.
Claims (12)
1. a kind of pyrolysis furnace processing method of nichrome boiler tube, it is characterised in that this method includes：To nichrome boiler tube
Inner surface is cleaned, and then under low oxygen partial pressure gas atmosphere, is first closed nickel chromium triangle with 55-150 DEG C/h the first programming rate
Golden boiler tube is warming up to 550-700 DEG C, and is incubated 5-50 hours, then with the second programming rate less than 150 DEG C/h by nichrome
Boiler tube is warming up to 750-1100 DEG C, and is incubated 5-100 hours；Wherein, it is provided with augmentation of heat transfer structure in the nichrome boiler tube
Part.
2. according to the method for claim 1, wherein, the mode of the cleaning is cleaning by degreasing method, it is preferable that the degreasing
Ablution includes：Ion processing, ungrease treatment, carrying out washing treatment and nitrogen are carried out successively to nichrome boiler tube inner surface to blow
Dry-cure.
3. according to the method for claim 2, wherein, the method for the ungrease treatment includes：Circulated with degreasing with cleaning fluid
It is constant to the pH for cleaning waste liquid to clean nichrome boiler tube inner surface；
Preferably, the condition of wash cycles includes：Temperature is 50-90 DEG C, and the time is 6-12 hours, the flow velocity of degreasing cleaning fluid
For 0.1-1m/s.
4. according to the method for claim 1, wherein, the low oxygen partial pressure gas is for water vapour and selected from CO2、CO、CH4、
C2H6、C3H8、NH3、H2、N2, at least one of Ar and He admixture of gas, and water vapour accounts for the volume of low oxygen partial pressure gas
Percentage is less than 7.5%；
Preferably, the low oxygen partial pressure gas is water vapour and CH4Admixture of gas, water vapour and CO2Admixture of gas,
Water vapour and CO admixture of gas or water vapour and H2Admixture of gas；
Preferably, the percentage by volume that water vapour accounts for low oxygen partial pressure gas is 2-7.5%, more preferably 2-6%.
5. according to the method for claim 1, wherein, first programming rate is 55-100 DEG C/h, soaking time 5-
20 hours.
6. according to the method for claim 1, wherein, second programming rate is 100 DEG C/below h, and soaking time is
10-60 hours；
Preferably, second programming rate is 30-100 DEG C/h, and soaking time is 15-50 hours.
7. according to the method described in any one in claim 1-6, wherein, with the second programming rate by nichrome boiler tube liter
Temperature is to 800-1000 DEG C.
8. according to the method described in any one in claim 1-7, the enhanced heat transfer member is twisted sheet, inner rib plate and interior
At least one of fin.
9. according to the method described in any one in claim 1-8, wherein, on the basis of the weight of nichrome boiler tube, institute
Stating the composition of nichrome boiler tube includes：Chromium 12-50wt%, nickel 20-50wt%, manganese 0.2-3wt%, silicon 0-3wt%, carbon 0-
0.75wt%, 0-5wt% trace element and trace element, surplus are iron；The trace element is niobium, molybdenum, titanium, tungsten, aluminium, zirconium
With the one or more in rare earth element, the trace element is sulphur and/or phosphorus.
10. the pyrolysis furnace nichrome boiler tube obtained by any one methods described in claim 1-9.
A kind of 11. method for producing ethene, it is characterised in that this method includes：To pyrolysis furnace with nichrome boiler tube
Reason, then in the obtained pyrolysis furnace of processing with carrying out hydrocarbon vapours cracking reaction, the method for the processing in nichrome boiler tube
For the method described in any one in claim 1-9.
12. according to the method for claim 11, wherein, the hydro carbons is gas hydrocarbon raw material or liquid hydrocarbon raw material；
Preferably, the gas hydrocarbon raw material is at least one of ethane, propane, butane and liquefied petroleum gas；
Preferably, the liquid hydrocarbon raw material is at least one of naphtha, condensate, hydrocracking tail oil and diesel oil.
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| CN201610543447.2A CN107604277A (en) | 2016-07-11 | 2016-07-11 | Processing method, thus obtained pyrolysis furnace nichrome boiler tube and the method for producing ethene of pyrolysis furnace nichrome boiler tube |
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| CN101294099A (en) * | 2007-04-28 | 2008-10-29 | 中国石油化工股份有限公司 | Method for inhibiting hydrocarbons steam cracking furnace from coking and carburizing |
| CN101475827A (en) * | 2008-01-04 | 2009-07-08 | 中国石油化工股份有限公司 | Pyrolysis furnace tube for cracking petroleum hydrocarbon |
| CN102807887A (en) * | 2011-05-31 | 2012-12-05 | 中国石油化工股份有限公司 | Cracking furnace tube for inhibiting catalytic coking of hydrocarbon cracking furnace tube, and manufacturing method thereof |
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2016
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101294099A (en) * | 2007-04-28 | 2008-10-29 | 中国石油化工股份有限公司 | Method for inhibiting hydrocarbons steam cracking furnace from coking and carburizing |
| CN101475827A (en) * | 2008-01-04 | 2009-07-08 | 中国石油化工股份有限公司 | Pyrolysis furnace tube for cracking petroleum hydrocarbon |
| CN102807887A (en) * | 2011-05-31 | 2012-12-05 | 中国石油化工股份有限公司 | Cracking furnace tube for inhibiting catalytic coking of hydrocarbon cracking furnace tube, and manufacturing method thereof |
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