WO2018120051A1 - Waste incineration fly ash stabilizing agent and preparation method therefor - Google Patents

Abstract

Provided is a waste incineration fly ash stabilizing agent, consisting of potassium dihydrogen phosphate, polyferric silicate sulfate, polyferric chloride and sepiolite mud, and the content of each component by weight respectively being: 40%-50% of the potassium dihydrogen phosphate, 20%-30% of the polyferric silicate sulfate, 20%-30% of the polyferric chloride, and 5%-10% of the sepiolite mud. At the same time, also provided is a method for preparing the waste incineration fly ash stabilizing agent, comprising the following steps: in the first step, respectively weighing each material in the above-mentioned weight percentages; in the second step, grinding the polyferric silicate sulfate, the polyferric chloride and the sepiolite mud until uniform, wherein the particle size of the polyferric silicate sulfate is not more than 0.2 mm, the particle size of the polyferric chloride is not more than 0.15 mm, and the particle size of the sepiolite mud is not more than 0.1 mm; and in the third step, adding the ground polyferric silicate sulfate, polyferric chloride and sepiolite mud to the potassium dihydrogen phosphate and stirring same until uniform, so as to prepare the waste incineration fly ash stabilizing agent. The components of the waste incineration fly ash stabilizing agent of the present invention are collocated in a reasonable manner, each component can synergistically play its role, and the treated fly ash can satisfy the admission requirements of "Standard for pollution control on the landfill site of Municipal Solid Waste " (GB16889-2008).

Description

Waste incineration fly ash stabilization agent and preparation method thereof Technical field

The invention relates to a waste incineration fly ash treatment medicament, in particular to a waste incineration fly ash stabilization medicament and a preparation method thereof.

Background technique

At present, with the accelerating urbanization process, the amount of urban domestic waste has increased sharply, and the growth momentum has not decreased. The pressure on the garbage surrounding city has become larger and larger, and the environmental and social problems have become one of the bottlenecks restricting urban development. Waste incineration treatment technology has been widely used at home and abroad because of its advantages in resource reduction and reduction. However, municipal solid waste incineration will produce incineration fly ash equivalent to 2% to 5% of the original waste quality. Fly ash contains water-soluble Cd, Pb, Zn, Cu, Cr and other harmful heavy metal substances. The list of hazardous wastes in China has clearly classified waste incineration fly ash as hazardous waste (No. HW18), which requires passivation and stabilization. Special treatments such as chemical treatment, in order to meet the requirements of the heavy metal leaching concentration value in the Domestic Waste Landfill Pollution Control Standard (GB16889-2008), can only enter the landfill for safe disposal.

The treatment methods of waste incineration fly ash mainly include chemical stabilization method, melting/glass solidification, cement solidification, acid or other solvent elution method, and safe landfill. The chemical stabilization method mainly uses a chemical agent to chemically react with harmful substances in fly ash to convert it into a process of low solubility, low migration and low toxicity. The chemical stabilization method has become a commonly used treatment method at home and abroad because of its simple operation and quick effect. However, it also has problems such as high treatment cost and unstable treatment effect, and there is a risk of secondary pollution.

Summary of the invention

In order to solve the above problems, the present invention provides a waste incineration fly ash stabilization agent, and a method for preparing the above-mentioned waste incineration fly ash stabilization agent, a waste incineration fly ash stabilization agent, which is composed of potassium dihydrogen phosphate and polysilicon The composition of acid ferric sulfate, polyferric chloride and sea foam mud, the content of each component by weight: potassium dihydrogen phosphate 40-50%, polymeric ferric sulfate 20-30%, polyferric chloride 20-30 %, sea foam mud 5-10%; the above preparation method of the waste incineration fly ash stabilization agent comprises the following steps:

1. Weigh each raw material according to the above weight percentage;

2. Grinding polyaluminum silicate sulfate, polyferric chloride and sea foam mud evenly;

Further, the particle size of the polymeric calcium silicate sulfate is not more than 0.2 mm;

Further, the particle size of the polyferric chloride is not more than 0.15 mm;

Further, the particle size of the sea foam is not more than 0.1 mm.

3. The ground polysilicate ferric sulfate, polyferric chloride and sea foam are added to the potassium dihydrogen phosphate and stirred uniformly to form a waste incineration fly ash stabilization agent.

The application of the above-mentioned waste incineration fly ash stabilization agent includes the following steps:

(1) conveying the fly ash to the mixer;

(2) After the fly ash is delivered, the agent is delivered to the mixer and dryly stirred until uniform;

(3) adding water and stirring until uniform;

(4) The stirred chelate (treated fly ash) is bagged and numbered, and after 24 hours of curing, it is sent to the landfill for landfill.

The technical solution adopted by the invention to solve the technical problem is: a waste incineration fly ash stabilization agent, consisting of potassium dihydrogen phosphate, polyferric sulfate, polyferric chloride, sea foam, and components by weight The contents are: potassium dihydrogen phosphate 40-50%, polymeric ferric sulfate 20-30%, polyferric chloride 20-30%, sea foam mud 5-10%; a waste incineration fly ash stabilization agent The preparation method comprises the following steps:

In the first step, potassium dihydrogen phosphate, polyferric sulfate ferric sulfate, polyferric chloride, and sea foam are weighed separately. The contents of each component by weight are: potassium dihydrogen phosphate 40-50%, polymeric silicic acid sulfuric acid 20-30% iron, 20-30% polyferric chloride, 5-10% sea foam mud;

In the second step, the polyferric silicate sulfate, the polyferric chloride, and the sea foam are uniformly ground;

Further, the particle size of the polymeric calcium silicate sulfate is not more than 0.2 mm;

Further, the particle size of the polyferric chloride is not more than 0.15 mm;

Further, the particle size of the sea foam is not more than 0.1 mm.

In the third step, the ground polysilicate ferric silicate, the polyferric chloride and the sea foam are added to the potassium dihydrogen phosphate and stirred uniformly to form a waste incineration fly ash stabilization agent.

The invention has the beneficial effects that the composition of the waste incineration fly ash stabilizing agent of the invention is reasonable, and the components can cooperate synergistically, and the plurality of solidifications such as adsorption, complexation reaction and precipitation reaction of the mineral lattice are utilized. The mechanism can permanently and effectively stabilize the heavy metals in the fly ash. The treated fly ash can meet the entry requirements of the Domestic Waste Landfill Pollution Control Standard (GB16889-2008); in addition, the stabilized chemical is inexpensive. The preparation and application process are simple, the operability is strong, and it is suitable for wide-ranging application.

detailed description

Embodiment 1

A waste incineration fly ash stabilization agent, the components and percentages thereof are as follows:

raw material Weight (KG) Weight percentage (%) Potassium dihydrogen phosphate 40 40 Polymeric ferric sulfate 30 30 Polyferric chloride 25 25 Sea foam 5 5 total 100 100

The preparation method of the above-mentioned waste incineration fly ash stabilization agent is as follows:

In the first step, weigh each raw material according to the weight percentage in the above table;

In the second step, the polyferric sulfate ferric sulfate is ground, and after pulverization, a sieve of 0.2 mm is used, and used;

The polyferric chloride is ground, crushed and passed through a 0.15 mm sieve, and used;

The sea foam mud is ground, crushed and passed through a 0.1 mm sieve, and used;

In the third step, the raw material after the grinding in step 2 is added to potassium dihydrogen phosphate and then stirred uniformly to form a waste incineration fly ash stabilization agent.

Application example of waste incineration fly ash stabilization agent: Take 5kg of fly ash from a waste incineration power plant in Shenzhen, add 1kg of waste incineration fly ash stabilization agent of the invention, stir evenly, add 0.75kg of water and continue stirring for 120 seconds until uniform. The treated fly ash (chelate) is bagged and numbered. The numbering method is: year + month + day + production batch format, this time number is 2016-10-12-001. Samples were taken after 24 hours of curing.

Detection method: According to the "Solid Waste Leaching Toxicity Leaching Method Acetate Buffer Solution Method" (HJ/T300-2007) for the leaching toxicity test, "Dangerous Waste Identification Standard Leaching Toxicity Identification" (GB5085.3-2007) to determine the heavy metal concentration of the leachate.

The test results show that the fly ash treated by the waste incineration fly ash stabilization agent of the invention can meet the admission requirements of the Domestic Waste Landfill Pollution Control Standard (GB16889-2008).

sample Pb Zn Cu Cr Ni Be Ba Hg As Se Cr6+ Cd Raw ash 9.12 300 53.9 0.33 0.60 0.001 0.856 0.027 0.091 0.006 0.116 8.72 Chelate 0.06 0.51 0.67 0.14 0.14 0.001 0.623 0.018 0.078 0.004 0.101 0.05

Remarks: The unit is mg/L

Embodiment 2

A waste incineration fly ash stabilization agent, the components and percentages thereof are as follows:

raw material Weight (KG) Weight percentage (%) Potassium dihydrogen phosphate 50 50 Polymeric ferric sulfate 20 20 Polyferric chloride 20 20 Sea foam 10 10 total 100 100

The above-mentioned waste incineration fly ash stabilizing agent is prepared in the same manner as in the first embodiment.

Application example of waste incineration fly ash stabilization agent: Take 10kg of fly ash from a waste incineration power plant in Wuhan, add 2.5kg of waste incineration fly ash stabilization agent of the invention, stir evenly, add 1.5kg of water and continue stirring for 120 seconds until uniform. The treated fly ash (chelate) is bagged and numbered. The numbering method is: year + month + day + production batch format, this time number is 2016-10-15-001. Samples were taken after 24 hours of curing.

The detection items and methods are the same as in the first embodiment.

The test results show that the fly ash treated by the waste incineration fly ash stabilization agent of the invention can meet the admission requirements of the Domestic Waste Landfill Pollution Control Standard (GB16889-2008).

sample Pb Zn Cu Cr Ni Be Ba Hg As Se Cr6+ Cd Raw ash 10.32 158 70.3 0.35 0.71 0.001 0.937 0.011 0.083 0.007 0.123 10.35 Chelate 0.05 0.43 0.52 0.13 0.11 0.001 0.246 0.99 0.058 0.003 0.091 0.07

Remarks: The unit is mg/L

Claims (2)

The invention relates to a waste incineration fly ash stabilization agent, characterized in that the medicament is composed of potassium dihydrogen phosphate, polyferric silicate ferric sulfate, polyferric chloride and sea foam, and the content of each component by weight is: phosphoric acid 40-50% dihydrogen potassium, 20-30% polyaluminum silicate sulfate, 20-30% polyferric chloride, 5-10% sea foam. A method for preparing a waste incineration fly ash stabilization agent, comprising the following steps: In the first step, potassium dihydrogen phosphate, polyferric sulfate ferric sulfate, polyferric chloride, and sea foam are weighed separately. The contents of each component by weight are: potassium dihydrogen phosphate 40-50%, polymeric silicic acid sulfuric acid 20-30% iron, 20-30% polyferric chloride, 5-10% sea foam mud; In the second step, the polyferric silicate sulfate, the polyferric chloride, and the sea foam are uniformly ground; Further, the particle size of the polymeric calcium silicate sulfate is not more than 0.2 mm; Further, the particle size of the polyferric chloride is not more than 0.15 mm; Further, the particle size of the sea foam is not more than 0.1 mm. In the third step, the ground polysilicate ferric silicate, the polyferric chloride and the sea foam are added to the potassium dihydrogen phosphate and stirred uniformly to form a waste incineration fly ash stabilization agent.