CN106833530B - Special chemical film covering agent for waste incineration fly ash transfer and landfill processes - Google Patents

Abstract

The invention relates to the technical field of environmental pollution treatment, in particular to a special chemical film coating agent for the process of transferring and filling waste incineration fly ash and a preparation method thereof. The chemical film coating agent comprises the following substances in percentage by mass: the functional component A is composed of a reaction liquid obtained after one or more of sludge protein liquid, percolate concentrated liquid or polyethylene glycol emulsion reacts with formaldehyde or polyformaldehyde: 20-40%, and one or more of polyacrylic emulsion, polyvinyl acetate emulsion or modified PVC emulsion as functional component B: 15-35%, auxiliary components consisting of penetrant and defoamer: 2-4% and the balance of water. The special chemical film covering agent for the fly ash prepared by the invention generates less foam when being applied, the film covering has higher compactness, impermeability, proper hardness, flexibility and adhesive force, the film forming has high covering strength, the film and an ash sample have good associativity, the stability is higher, and the special chemical film covering agent has stronger fixed isolation effect on the fly ash.

Description

Special chemical film covering agent for waste incineration fly ash transfer and landfill processes

Technical Field

The invention relates to the technical field of environmental pollution treatment, in particular to a special chemical film coating agent for the process of transferring and filling waste incineration fly ash and a preparation method thereof.

Background

The waste incineration fly ash is classified as dangerous waste because of containing heavy metal with higher concentration and dioxin type persistent organic pollutants, and fly ash is easy to form into air in the processes of transportation, open-air landfill and the like, so that the dust content in the air is increased, the ecological toxicity of haze is aggravated, the air is seriously polluted, and the health and the ecological environment of residents are harmed.

When the flying ash is filled in a large area, if the flying ash from the waste incineration is isolated and the dust loss is reduced by adopting a direct film covering mode, the defects of light film weight, easy air trapping, easy aging, short service life and the like exist, and meanwhile, the cost of the film is higher, so that the waste of resources is caused, the covering and dismounting procedures are troublesome, and the speed-up and efficiency-improvement of the engineering are not facilitated.

The fly ash is fixed and isolated by directly spraying the chemical film coating agent, so that the method is simple to operate, good in film coating effect and controllable in cost. However, the fly ash contains a large amount of Ca, Mg, Fe, silicate and heavy metal salts, the permeability and the binding property of the fly ash to common chemical film coating agents such as polyvinyl chloride emulsion, polypropylene emulsion, polyethylene emulsion and the like are poor, and a film generated after spraying is easy to peel off, so that the film coating failure is caused; the bonding property to common acrylic polymers is too strong, so that the coated film is easy to break, a continuous film cannot be formed, and the covering isolation property is poor.

Therefore, the chemical film-coating agent with high film-forming performance and special for the fly ash generated by burning the household garbage is developed, and has certain positive promotion effects on the aspects of reducing the dust loss in the fly ash transferring and stacking processes, reducing the haze concentration and the ecological toxicity, enhancing the management of dangerous wastes, protecting the living environment and the like.

Disclosure of Invention

The invention provides a chemical film covering agent with high film forming performance special for waste incineration fly ash and a preparation method thereof, aiming at the defect that film covering failure is caused by the phenomena of too low or too strong film binding property and the like when a common film covering agent is applied to waste incineration fly ash transportation and landfill.

The invention is realized by the following technical scheme:

a chemical film covering agent special for the process of transporting and piling up waste incineration fly ash,

functional component A: 20 to 40 percent;

functional component B: 15 to 35 percent;

auxiliary components: 2 to 4 percent;

the balance of water;

the functional component A is: a reaction solution of one or a combination of more of sludge protein solution, percolate concentrated solution or polyethylene glycol emulsion and formaldehyde or polyformaldehyde under the reaction conditions that the pH value is 9-12 and the temperature is 60-80 ℃;

the sludge protein liquid and the percolate concentrated liquid contain a large amount of complex long-chain protein substances and humus substances, the molecular configuration is complex, the uniform structure composition is avoided, but the long-chain protein liquid and the percolate concentrated liquid have the common characteristic that the long-chain molecular structure contains a large amount of active groups such as-OH, -SH, -NH, -COO and the like, and the active groups can be subjected to condensation polymerization with aldehyde substances to form a high-molecular polymer. The partial structural formula of the effective components in the sludge protein liquid and the percolate concentrated liquid is shown in figure 1.

The functional component B is: one or more of polyacrylic emulsion, vinyl acetate emulsion or modified PVC emulsion;

the auxiliary components are as follows: penetrants and defoamers.

The mass ratio of one or more of the sludge protein liquid, the percolate concentrated liquid or the polyethylene glycol emulsion to the formaldehyde or the polyformaldehyde is 1.2-2.5: 1.

the penetrating agent is one or a combination of more of OEP-70, AEP and HA-LF, and the substances are all alkaline-resistant surfactants so as to adapt to alkaline components such as lime and the like in the fly ash.

The defoaming agent is one or a combination of more of polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene amine ether, polyoxypropylene glycerol ether and polyoxypropylene polyoxyethylene glycerol ether.

The mass ratio of the penetrating agent to the defoaming agent is 1-1.5: 1.

a preparation method of a special chemical film coating agent in the process of transporting and filling waste incineration fly ash is characterized by comprising the following steps:

(1) one or more of the sludge protein liquid, the percolate concentrated liquid or the polyethylene glycol emulsion is combined with formaldehyde or polyformaldehyde according to the weight ratio of 1.2-2.5: 1, adding the mixture into a reaction kettle, adjusting the pH value of the solution to 9-12 by using alkali liquor, and reacting for 10-30 minutes at 60-80 ℃;

(2) then adding 15-35% of functional component B, 2-4% of auxiliary component and the balance of water into the reaction solution, and reacting for 5-10 minutes at 70-95 ℃;

(3) adjusting the pH value of the solution to be constant at 9-12 by using alkali liquor, and generating a special chemical film coating agent in the process of transporting and piling up the waste incineration fly ash after the solution is recovered to normal temperature.

When the chemical film-coating agent special for the fly ash is used, the chemical film-coating agent can be directly sprayed, or can be sprayed after being diluted to a certain concentration by adding water according to needs, and the film-coating isolation effect can be achieved.

The invention has the beneficial effects that:

(1) one of the raw materials of the chemical film covering agent prepared by the invention is sludge protein liquid or leachate concentrated liquid, which can promote the waste reutilization of sludge and leachate and reduce the production cost.

(2) Macromolecular active ingredients in the sludge protein liquid or percolate concentrated liquid form a reticular polymer serving as a main functional component of the chemical film coating agent through cross-linking polymerization of formaldehyde micromolecules, the polymer contains a large number of amino, sulfydryl, carboxyl, hydroxyl and other components, and the groups have strong complexing capability on high-content Ca, Fe, Mg, Al, Na, K and other compounds in the fly ash, so that the coating strength of a formed film is greatly improved, and the applicability to the fly ash is strong.

(3) The functional component B added in the invention interacts and crosslinks with the functional component A to form a film with a net structure under the using condition, and the film has proper hardness, flexibility and adhesive force.

(4) The penetrant and the defoaming agent added in the invention can reduce the surface tension of the coated film, accelerate the film drying, reduce the foam generation and improve the compactness and impermeability of the coated film; meanwhile, the penetrant selects the surfactant with alkali resistance to adapt to the alkali components such as lime and the like contained in the fly ash, and overcomes the defects that the common film forming agent is possibly reacted with the fly ash or corroded and the like when being applied to fly ash film coating.

Drawings

FIG. 1 partial structural formula of effective component in sludge protein liquid and percolate concentrated liquid

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

Example 1

(1) Mixing the sludge protein liquid with formaldehyde according to the ratio of 1.2: adding the mixture into a reaction kettle according to the mass ratio of 1, adjusting the pH value of the solution to 11 by using alkali liquor, and reacting for 30 minutes at 60 ℃ to obtain reaction liquid;

(2) taking 30% by mass of reaction liquid, adding 15% by mass of polyacrylic acid emulsion, 1% by mass of OEP-70, 1% by mass of polyoxyethylene polyoxypropylene pentaerythritol ether and the balance of water, and reacting for 5 minutes at 95 ℃;

(3) finally, regulating the pH value of the solution to be constant at 11 by using alkali liquor, and recovering the solution to normal temperature to generate the special chemical film coating agent for the garbage incineration fly ash transportation and landfill process.

Example 2

(1) Mixing a mixture of the sludge protein liquid and the percolate concentrated liquid with polyformaldehyde according to the proportion of 1.8: adding the mixture into a reaction kettle according to the mass ratio of 1, adjusting the pH value of the solution to 10 by using alkali liquor, and reacting for 20 minutes at 70 ℃ to obtain reaction liquid;

(2) taking reaction liquid with the mass percent of 40%, adding vinyl acetate emulsion with the mass percent of 25%, surfactant with alkali resistance of 1.5%, polyoxyethylene polyoxypropylene ether of 1% and the balance of water, and reacting for 7 minutes at the temperature of 85 ℃;

(3) finally, regulating the pH value of the solution to be constant at 10 by using alkali liquor, and recovering the solution to normal temperature to generate the special chemical film coating agent for the garbage incineration fly ash transportation and landfill process.

Example 3

(1) Mixing the polyethylene glycol emulsion and polyformaldehyde according to the weight ratio of 1.5: adding the mixture into a reaction kettle according to the mass ratio of 1, adjusting the pH value of the solution to 12 by using alkali liquor, and reacting for 15 minutes at 75 ℃ to obtain reaction liquid;

(2) taking 35% of reaction liquid by mass, adding 20% of mixture of polyacrylic acid emulsion and modified PVC emulsion by mass, 1.8% of HA-LF, 1.2% of mixture of polyoxypropylene glycerol ether and polyoxypropylene polyoxyethylene glycerol ether and the balance of water, and reacting for 8 minutes at 75 ℃;

(3) finally, regulating the pH value of the solution to be constant at 12 by using alkali liquor, and recovering the solution to normal temperature to generate the special chemical film coating agent in the process of transporting and piling up the waste incineration fly ash.

Example 4

(1) And mixing the mixture of the percolate concentrated solution and the polyethylene glycol emulsion with polyformaldehyde according to the weight ratio of 2.4: adding the mixture into a reaction kettle according to the mass ratio of 1, adjusting the pH value of the solution to 9 by using alkali liquor, and reacting for 10 minutes at 80 ℃ to obtain reaction liquid;

(2) taking 25% of reaction liquid by mass, adding 35% of vinyl acetate acid emulsion and modified PVC emulsion mixture by mass, 2% of AEP and HA-LF mixture by mass, 1.5% of polyoxypropylene glycerol ether and the balance of water, and reacting for 10 minutes at 70 ℃;

(3) finally, regulating the pH value of the solution to be constant at 9 by using alkali liquor, and recovering the solution to normal temperature to generate the special chemical film coating agent for the garbage incineration fly ash transportation and landfill process.

Experiment:

the chemical film coating agents in examples 1 to 4 were dissolved in tap water to prepare 12% solutions, which are labeled a, b, c, and d, respectively, and polyacrylic acid emulsion with a mass concentration of 12% was used as a common film forming agent, which is labeled a.

And screening the waste incineration fly ash by using a 100-mesh standard screen to prepare an experimental ash sample for later use.

The ash sample is put into 5 glass culture dishes with the diameter of 10cm, which are respectively marked as No. 1, No. 2, No. 3, No. 4 and No. 5, and the surface of the ash sample is flush with the height of the culture dishes. And respectively spraying the chemical film coating agent solutions a, b, c and d and the common film forming agent A into culture dishes No. 1, No. 2, No. 3, No. 4 and No. 5 by using a 2.0L sprayer, wherein the spraying amount is 20 ml.

The time for moisture absorption, aggregation and film formation of the ash sample in each petri dish was observed and is shown in table 1.

After the film formation is completed, the wind speed of the air compressor is tested to be 20m/s (about 8-9 grade wind) by using an anemograph, the wind blowing angle is 45 degrees, the single wind blowing time is 1 minute, the wind blowing experiment is carried out on the 1-5# gray sample, and the experimental result is shown in the table 2.

TABLE 1 time chart of the moisture absorption, agglomeration and film formation of the ash sample in each Petri dish

Unit: s

Index of experiment	1#	2#	3#	4#	5#
						Wetting time	0.43	0.68	0.59	0.72	0.57
Time to start agglomeration	1.34	1.18	1.52	1.29	1.05
						Overall film formation time	2.59	2.38	2.98	2.72	/

TABLE 2 Ash sample blowing test results in each culture dish

Unit: g

	1#	2#	3#	4#	5#
						Before blowing	220.65	220.73	220.71	220.68	220.66
The first time of blowing	220.65	220.73	220.71	220.68	220.03
						The second time of blowing	220.65	220.73	220.70	220.67	219.48
Third air blowing	220.65	220.73	220.70	220.68	217.35
						Amount of loss	0	0	0.01	0	3.31
The loss rate%	0	0	0.005	0	1.5

As can be seen from Table 1, the wetting time and the agglomeration starting time of the special chemical film coating agent for fly ash synthesized by the invention are relatively slower than those of the common film forming agent, but the whole film forming time is finished within about 3s, and the formed film of the common film forming agent is very easy to break and cannot form a continuous and complete film.

Meanwhile, the air blowing experimental results in table 2 show that after the special chemical film coating agent for fly ash synthesized by the invention is sprayed on the surface of fly ash and forms a film, the film stability is high and the loss of the ash sample is almost zero after the special chemical film coating agent is blown for 3 minutes at the wind speed of 8-9 grades, while the loss rate of the ash sample is about 1.5 percent under the air blowing experimental conditions because the common film forming agent can not form a continuous and complete film.

Therefore, experiments compare that the fly ash special chemical film coating agent synthesized by the invention has the advantages of quick moisture absorption and agglomeration time, good combination of the formed film and an ash sample, high film stability and strong fixation and isolation effect on fly ash.

Although the preferred embodiments of the present invention have been described, the present invention is not limited to the above-mentioned embodiments, which are only illustrative and not restrictive, and those skilled in the art can make many modifications without departing from the spirit and scope of the present invention as claimed in the appended claims.

Claims (6)

1. A special chemical film coating agent for the process of transporting and piling up waste incineration fly ash is composed of the following substances in percentage by mass:

functional component A: 20 to 40 percent;

functional component B: 15 to 35 percent;

auxiliary components: 2 to 4 percent;

the balance of water;

the functional component A is: a reaction solution of one or a combination of more of sludge protein solution, percolate concentrated solution or polyethylene glycol emulsion and formaldehyde or polyformaldehyde under the reaction conditions that the pH value is 9-12 and the temperature is 60-80 ℃;

the functional component B is: one or more of polyacrylic emulsion, polyvinyl acetate emulsion or modified PVC emulsion;

the auxiliary components are as follows: alkali-resistant penetrant and defoaming agent.

2. The chemical coating agent special for the process of transporting and stacking waste incineration fly ash according to claim 1, wherein the chemical coating agent comprises: the mass ratio of one or more of the sludge protein liquid, the percolate concentrated liquid or the polyethylene glycol emulsion to the formaldehyde or the polyformaldehyde is 1.2-2.5: 1.

3. the chemical coating agent special for the process of transporting and stacking waste incineration fly ash according to claim 1, wherein the chemical coating agent comprises: the alkali-resistant penetrant is one or a combination of more of OEP-70, AEP and HA-LF.

4. The chemical coating agent special for the process of transporting and stacking waste incineration fly ash according to claim 1, wherein the chemical coating agent comprises: the defoaming agent is one or a combination of more of polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene amine ether, polyoxypropylene glycerol ether and polyoxypropylene polyoxyethylene glycerol ether.

5. The chemical coating agent special for the process of transporting and stacking waste incineration fly ash according to claim 1, wherein the chemical coating agent comprises: the mass ratio of the alkali-resistant penetrant to the defoaming agent is 1-1.5: 1.

6. the method for preparing the chemical film coating agent specially used in the process of transporting and stacking the fly ash generated by burning the garbage according to claim 1, which is characterized in that:

(1) one or more of the sludge protein liquid, the percolate concentrated liquid or the polyethylene glycol emulsion is combined with formaldehyde or polyformaldehyde according to the weight ratio of 1.2-2.5: 1, adding the mixture into a reaction kettle, adjusting the pH value of the solution to 9-12 by using alkali liquor, and reacting for 10-30 minutes at 60-80 ℃;

(2) then adding 15-35% of functional component B, 2-4% of auxiliary component and the balance of water into the reaction solution, and reacting for 5-10 minutes at 70-95 ℃;

(3) adjusting the pH value of the solution to be constant at 9-12 by using alkali liquor, and generating a special chemical film coating agent in the process of transporting and piling up the waste incineration fly ash after the solution is recovered to normal temperature.

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