CN108178488A - A kind of preparation method of sludge dehydrating agent - Google Patents
A kind of preparation method of sludge dehydrating agent Download PDFInfo
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- CN108178488A CN108178488A CN201711316829.2A CN201711316829A CN108178488A CN 108178488 A CN108178488 A CN 108178488A CN 201711316829 A CN201711316829 A CN 201711316829A CN 108178488 A CN108178488 A CN 108178488A
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- sludge
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- dehydrating agent
- waste gypsum
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/14—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents
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- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
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- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Treatment Of Sludge (AREA)
Abstract
The invention discloses a kind of preparation methods of sludge dehydrating agent, belong to sludge treatment field.The present invention is based on waste gypsum, realize the treatment of wastes with processes of wastes against one another, hydrochloric acid is utilized simultaneously, calcining is surface-treated waste gypsum, remove surface impurity, waste gypsum after one aspect of the present invention makes surface treatment with initiator carries out graft copolymerization with acrylamide monomer, improve waste gypsum molecular weight, introduce active group, enhance its flocculation ability, on the other hand inorganic polymer conditioner is used, organic high polymer coagulant is compounded, weaken the affinity of colloid particle and water, destroy the colloform texture of sludge, sludge is made to be easier to be dehydrated, conditioner is used in combination with flocculant, the adsorption layer of the mixed polymer of formation more crypto set, the contact of polymer polymerizing object has stronger bridging action, so as to improve sludge dewatering effect.The problem of it is difficult degradation under field conditions (factors) that the present invention, which solves current dehydrating agent, is unfavorable for environmental protection, and Treatment of Sludge is ineffective.
Description
Technical field
The invention belongs to sludge treatment field, and in particular to a kind of preparation method of sludge dehydrating agent.
Background technology
Sludge is the final product of sewage disposal, and pollutant concentration degree is high, and comparison of ingredients is complicated, and the content of organic matter is high, parent
It is aqueous strong.It is based on aerobic, anaerobe, while it is residual to be also mixed into the silt particle carried in raw sewage, fiber, animals and plants
The mixture of the Various Complexes such as organic matter, metal, germ, worm's ovum, the colloid of body and absorption on it.Dirt for large size city
For water treatment plant, due to there is a large amount of industrial wastewater to be discharged into system, cause the content of beary metal in sewage sludge higher, wherein
Often near or above receiving standard of the sludge as agricultural compost, the sludge discharged from sewage treatment plant is general for copper, Zn content
It is a kind of loose, glue-dissolving shape lotion object of the water content 95% ~ 99%, there is light specific gravity（Less than or equal to 1kg/cm3）, volume it is huge
Greatly（It is the decades of times of contained solids volume）, thixotropy it is strong（It is not easy to be dehydrated）, there is the physics and chemistry of easily corrupt stench, because
And extremely it is unfavorable for processing and transport.With the development of industry with the quickening of urbanization process and domestic sewage disposal cause
Development, municipal sludge are the inevitable products in municipal sewage plant, and sewage plant total process water yield and degree for the treatment of will be continuous
Expand and improve, the sludge quantity of generation also increasingly increases.It is estimated that Chinese city sludge of sewage treatment plant annual output has surpassed at present
Cross 30,000,000 tons.Specific resistance to filtration is to solve the problems, such as the very important system of urban water pollution, and specific resistance to filtration is
Sewage disposal is able to the guarantee finally implemented, and in developed country, sludge treatment is extremely important link, and investment accounts for dirt
The 50% ~ 70% of water treatment plant's gross investment.Sludge dewatering is to reduce sludge subsequent processing as most important pretreatment process
With the very the key link of cost of disposal one.In Sludge landfill, sludge dewatering can greatly reduce sludge accumulation place,
It minimizes transport costs, reduces the percolate of landfill yard, prevent from filling the destruction to earth's surface and groundwater environment.It is carried out to sludge
During compost treatment, sludge dewatering can substantially reduce moisture percentage in sewage sludge, so as to meet requirement of the compost to sludge with low moisture content.
A large amount of moisture is usually contained in sludge, moisture content is up to 97.5%~99.5%, and the volume for leading to sludge is very huge, to rear
Continuous treatment process and conveyer belt come very big difficulty and are added significantly to processing cost, therefore.Sludge must be carried out at dehydration
Reason, to reduce the volume of sludge.At present frequently with method be that sludge is improved with one or more of chemical agents, so as to
Change the property of mud granule, convenient for the removal of contained humidity in sludge.Current most common sludge dehydrating agent is cationic
Polyacrylamide（CPAM）, polyacrylamide, molysite, aluminium salt, white lime etc., but there is also certain for these dehydrating agents
Problem：As although CPAM has preferable sludge dewatering effect, it is difficult degradation under field conditions (factors), and two are caused to environment
Secondary pollution, and the organic solvents such as exhibiting high surface activating agent used in CPAM building-up processes also can cause environmental pollution；
And partially dehydrated dose of water solubility is poor, it is impossible to which quick dissolving causes dehydrating effect relatively low, it is impossible to sludge moisture content be made to drop to 60%
Below.Therefore, producing a kind of dehydrating effect, good sludge dehydrating agent has the very big market demand.
Invention content
The technical problems to be solved by the invention：It is difficult degradation under field conditions (factors) for current dehydrating agent, and at certain
Using many volatile ingredients in a little dehydrating agent building-up processes, cause to be unfavorable for environmental protection, and Treatment of Sludge is ineffective asks
Topic, provides a kind of preparation method of sludge dehydrating agent.
In order to solve the above technical problems, the present invention is using technical solution as described below：
A kind of preparation method of sludge dehydrating agent, which is characterized in that the preparation method includes the following steps：
（1）Waste gypsum is crushed, is sieved, obtains sieving, in mass ratio 1：3 ~ 4, sieving, hydrochloric acid solution are mixed
It closes, impregnates 1 ~ 2h, filtering obtains filter residue, filter residue is washed with deionized, the filter residue after must washing exists the filter residue after washing
It is calcined at 500 ~ 600 DEG C of temperature, is cooled to room temperature, obtains cooling thing；
（2）Count in parts by weight, take 20 ~ 30 parts of water, 10 ~ 12 parts of cooling things, 7 ~ 8 parts of styrene, 3 ~ 4 parts of polyamide, 1 ~ 2 part draw
Hair agent, which is put into container, reacts, and is heated to 50 ~ 60 DEG C, and be stirred 25 ~ 30min, reacts 2 ~ 3h, obtain reaction stirred；
（3）Waste gypsum is crushed, 70 ~ 100 mesh sieve is crossed, obtains sieving, in mass ratio 20 ~ 30：10~15：0.1~0.3：3~
4, water, bodied ferric sulfate, polyacrylamide, sieving are mixed, 1 ~ 2h is reacted at 50 ~ 70 DEG C of temperature, obtains reactant；
（4）In mass ratio 0.3 ~ 0.7：1 ~ 3, reaction stirred, reactant are stirred, is uniformly mixed, obtains mixture, it will be mixed
It closes object to be freeze-dried, collects dried object to get sludge dehydrating agent.
The step（2）Middle initiator be potassium peroxydisulfate, cerous nitrate it is therein any one.
Compared with other methods, advantageous effects are the present invention：The present invention realizes the treatment of wastes with processes of wastes against one another based on waste gypsum,
Waste gypsum is surface-treated using hydrochloric acid, calcining simultaneously, removes surface impurity, one aspect of the present invention initiator makes surface
Treated, and waste gypsum carries out graft copolymerization with acrylamide monomer, improves waste gypsum molecular weight, introduces active group,
Its flocculation ability is enhanced, is on the other hand compounded with inorganic polymer conditioner, organic high polymer coagulant, makes colloid micro-
The affinity of grain and water weakens, and destroys the colloform texture of sludge, sludge is made to be easier to be dehydrated, conditioner and flocculant of the present invention
It is used in combination, the adsorption layer more crypto set of the mixed polymer of formation, the contact of Polymer-Polymer has stronger build bridge to make
With so as to improve sludge dewatering effect.
Specific embodiment
Initiator be potassium peroxydisulfate, cerous nitrate it is therein any one.
A kind of preparation method of sludge dehydrating agent, the preparation method include the following steps：
（1）Waste gypsum is crushed, 70 ~ 100 mesh sieve is crossed, obtains sieving, in mass ratio 1：3 ~ 4, by sieving, 1.5mol/L
Hydrochloric acid solution is mixed, and impregnates 1 ~ 2h, and filtering obtains filter residue, filter residue is washed with deionized, the filter residue after must washing, will
Filter residue after washing is calcined at 500 ~ 600 DEG C of temperature, is calcined 1 ~ 2h, is cooled to room temperature, obtains cooling thing；
（2）Count in parts by weight, take 20 ~ 30 parts of water, 10 ~ 12 parts of cooling things, 7 ~ 8 parts of styrene, 3 ~ 4 parts of polyamide, 1 ~ 2 part draw
Hair agent, which is put into container, reacts, and is heated to 50 ~ 60 DEG C, is stirred 25 ~ 30min with 100 ~ 150r/min, reacts 2 ~ 3h, must stir
Mix reactant；
（3）Waste gypsum is crushed, 70 ~ 100 mesh sieve is crossed, obtains sieving, in mass ratio 20 ~ 30：10~15：0.1~0.3：3~
4, water, bodied ferric sulfate, polyacrylamide, sieving are mixed, 1 ~ 2h is reacted at 50 ~ 70 DEG C of temperature, obtains reactant；
（4）In mass ratio 0.3 ~ 0.7：1 ~ 3, reaction stirred, reactant are stirred, stir speed (S.S.) is 100 ~ 150r/
Min is uniformly mixed, obtains mixture, mixture is freeze-dried, and dry 10 ~ 12h collects dried object to get sludge dewatering
Agent.
Example 1
Initiator is potassium peroxydisulfate.
A kind of preparation method of sludge dehydrating agent, the preparation method include the following steps：
（1）Waste gypsum is crushed, 70 mesh sieve is crossed, obtains sieving, in mass ratio 1：3, sieving, 1.5mol/L hydrochloric acid is molten
Liquid is mixed, and impregnates 1h, and filtering obtains filter residue, filter residue is washed with deionized, the filter residue after must washing, after washing
Filter residue is calcined at 500 DEG C of temperature, is calcined 1h, is cooled to room temperature, obtains cooling thing；
（2）It counts in parts by weight, 20 parts of water, 10 parts of cooling things, 7 parts of styrene, 3 parts of polyamide, 1 part of initiator is taken to be put into container
Middle reaction is heated to 50 DEG C, is stirred 25min with 100r/min, reacts 2h, obtain reaction stirred；
（3）Waste gypsum is crushed, 70 mesh sieve is crossed, obtains sieving, in mass ratio 20：10：0.1：3, by water, polyaluminum sulfate
Iron, polyacrylamide, sieving are mixed, and are reacted 1h under temperature 50 C, are obtained reactant；
（4）In mass ratio 0.3：1, reaction stirred, reactant are stirred, stir speed (S.S.) 100r/min, are uniformly mixed,
Mixture is obtained, mixture is freeze-dried, dry 10h collects dried object to get sludge dehydrating agent.
Example 2
Initiator is cerous nitrate.
A kind of preparation method of sludge dehydrating agent, the preparation method include the following steps：
（1）Waste gypsum is crushed, is sieved with 100 mesh sieve, obtains sieving, in mass ratio 1：4, by sieving, 1.5mol/L hydrochloric acid
Solution is mixed, and impregnates 2h, and filtering obtains filter residue, filter residue is washed with deionized, the filter residue after must washing, after washing
Filter residue calcined at 600 DEG C of temperature, calcine 2h, be cooled to room temperature, obtain cooling thing；
（2）It counts in parts by weight, 30 parts of water, 12 parts of cooling things, 8 parts of styrene, 4 parts of polyamide, 2 parts of initiators is taken to be put into container
Middle reaction is heated to 60 DEG C, is stirred 30min with 150r/min, reacts 3h, obtain reaction stirred；
（3）Waste gypsum is crushed, is sieved with 100 mesh sieve, obtains sieving, in mass ratio 30：15：0.3：4, by water, polyaluminum sulfate
Iron, polyacrylamide, sieving are mixed, and are reacted 2h under temperature 70 C, are obtained reactant；
（4）In mass ratio 0.7：3, reaction stirred, reactant are stirred, stir speed (S.S.) 150r/min, are uniformly mixed,
Mixture is obtained, mixture is freeze-dried, dry 12h collects dried object to get sludge dehydrating agent.
Example 3
Initiator is potassium peroxydisulfate.
A kind of preparation method of sludge dehydrating agent, the preparation method include the following steps：
（1）Waste gypsum is crushed, 85 mesh sieve is crossed, obtains sieving, in mass ratio 1：3.5, by sieving, 1.5mol/L hydrochloric acid
Solution is mixed, and impregnates 1.5h, and filtering obtains filter residue, filter residue is washed with deionized, the filter residue after must washing will wash
Filter residue afterwards is calcined at 550 DEG C of temperature, is calcined 1.5h, is cooled to room temperature, obtains cooling thing；
（2）It counts in parts by weight, 25 parts of water, 11 parts of cooling things, 7.5 parts of styrene, 3.5 parts of polyamide, 1.5 parts of initiators is taken to put
Enter in container and react, be heated to 55 DEG C, 27min is stirred with 125r/min, 2.5h is reacted, obtains reaction stirred；
（3）Waste gypsum is crushed, 85 mesh sieve is crossed, obtains sieving, in mass ratio 25：12.5：0.2：3.5, by water, polymerised sulphur
Sour iron, polyacrylamide, sieving are mixed, and are reacted 1.5h under temperature 60 C, are obtained reactant；
（4）In mass ratio 0.5：2, reaction stirred, reactant are stirred, stir speed (S.S.) 125r/min, are uniformly mixed,
Mixture is obtained, mixture is freeze-dried, dry 11h collects dried object to get sludge dehydrating agent.
Reference examples：The sludge dehydrating agent of Hangzhou company production.
The sludge dehydrating agent of sludge dehydrating agent made from above-described embodiment and reference examples is respectively applied to certain municipal sewage
Treatment plant's sludge to be drained off (moisture content 96% ~ 98%, pH value 6.8), dosage 50mg/L are observed and recorded after 2 days as a result, surveying
Test result is shown in Table 1.
| Test event | Example 1 | Example 2 | Example 3 | Reference examples |
| Filtrate turbidity（NTU） | 2.16 | 2.31 | 2.24 | 2.75~3.5 |
| Moisture content % after processing | 36.2 | 34.7 | 38.1 | 64~71.6 |
| Solution rate | Comparatively fast | Comparatively fast | Comparatively fast | Slowly |
Summary, sewage dehydrating agent dehydrating effect of the invention it is good and prepare dehydrating agent have it is good environmental-friendly
Property, it is worthy to be popularized.
Claims (2)
1. a kind of preparation method of sludge dehydrating agent, which is characterized in that the preparation method includes the following steps：
（1）Waste gypsum is crushed, is sieved, obtains sieving, in mass ratio 1：3 ~ 4, sieving, hydrochloric acid solution are mixed
It closes, impregnates 1 ~ 2h, filtering obtains filter residue, filter residue is washed with deionized, the filter residue after must washing exists the filter residue after washing
It is calcined at 500 ~ 600 DEG C of temperature, is cooled to room temperature, obtains cooling thing；
（2）Count in parts by weight, take 20 ~ 30 parts of water, 10 ~ 12 parts of cooling things, 7 ~ 8 parts of styrene, 3 ~ 4 parts of polyamide, 1 ~ 2 part draw
Hair agent, which is put into container, reacts, and is heated to 50 ~ 60 DEG C, and be stirred 25 ~ 30min, reacts 2 ~ 3h, obtain reaction stirred；
（3）Waste gypsum is crushed, 70 ~ 100 mesh sieve is crossed, obtains sieving, in mass ratio 20 ~ 30：10~15：0.1~0.3：3~
4, water, bodied ferric sulfate, polyacrylamide, sieving are mixed, 1 ~ 2h is reacted at 50 ~ 70 DEG C of temperature, obtains reactant；
（4）In mass ratio 0.3 ~ 0.7：1 ~ 3, reaction stirred, reactant are stirred, is uniformly mixed, obtains mixture, it will be mixed
It closes object to be freeze-dried, collects dried object to get sludge dehydrating agent.
2. the preparation method of sludge dehydrating agent according to claim 1, which is characterized in that the step（2）Middle initiator is
Potassium peroxydisulfate, cerous nitrate it is therein any one.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114011387A (en) * | 2021-12-23 | 2022-02-08 | 湖北康创科技有限公司 | Composite sludge dehydrating agent and preparation method thereof |
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| CN114011387A (en) * | 2021-12-23 | 2022-02-08 | 湖北康创科技有限公司 | Composite sludge dehydrating agent and preparation method thereof |
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