WO2014079221A1

WO2014079221A1 - Reagent for processing fly ash whilst incinerating waste

Info

Publication number: WO2014079221A1
Application number: PCT/CN2013/079498
Authority: WO
Inventors: 赵晓峰; 吴燕琦; 杨蕾; 刘红
Original assignee: 深圳市能源环保有限公司
Priority date: 2012-11-22
Filing date: 2013-07-17
Publication date: 2014-05-30
Also published as: CN102974068B; CN102974068A

Abstract

In order to solve the problem that the method of using chelating agents including phosphates to harmlessly process fly ash has a bad effect on fly ash with a high heavy metal content, disclosed in the present invention is a reagent for processing fly ash whilst incinerating waste, which uses the combined action of an activation and a composite phosphate, wherein the activation decreases the reactivity of the calcium ion and the magnesium ion by activating the reactivity of heavy metal ions during the process so that the composite phosphate can fully react with the heavy metal ions, thus greatly enhancing the heavy metal capturing efficiency of the composite phosphate. The reagent for processing fly ash during incinerating waste provided by the present invention comprises the following ingredients by weight: 20%-60% of an activation (Activation), 15%-50% of a composite phosphate (Composite Phosphate), 20%-50% of a solidification (Solidification) and 1%-5% of an auxiliary ingredient. The composite phosphate is formed by mixing multiple compounds containing phosphorus including a phosphate, a dihydric phosphate, etc. The composite phosphate acts together with the activation, which not only improves the heavy metal capturing efficiency, but also has the advantage of low cost.

Description

Waste incineration fly ash treatment agent

Technical field

The invention relates to a waste incineration fly ash treatment technology, in particular to a waste incineration fly ash treatment medicament.

Background technique

Fly ash from waste incineration is a kind of hazardous waste. It contains heavy metals such as lead, cadmium, mercury and chromium, and persistent organic pollutants such as dioxins, which are extremely harmful to human health and the environment. Therefore, proper disposal of fly ash is of great significance for protecting the health of the citizens and promoting sustainable economic development.

At present, the disposal of fly ash in foreign countries mainly adopts landfill and harmless treatment. The harmless treatment method includes a chemical treatment method and a melting method. Domestic fly ash processing technology is still in its infancy, and most of them cite chelating agents abroad for the treatment of fly ash. The process has obvious effect on the general fly ash and the process is simple, but the method of adding the chelating agent to the fly ash harmless treatment has poor treatment effect on the high heavy metal fly ash, and the treatment cost is high due to the high price of the chelating agent. Not suitable for large-scale promotion of applications.

Waste incineration fly ash has a high content of heavy metals. In addition to heavy metals, it also contains a large amount of calcium Ca and magnesium. Conventional chelating agents do not effectively distinguish between calcium, magnesium and heavy metal elements, resulting in the wasting of effective chelating coordination bonds and the low capture rate of heavy metals. The diacid salt is also a kind of chelating agent. The traditional diacid salt has no selectivity for heavy metal elements, most of which react with calcium and magnesium elements, and only a small part reacts with heavy metal ions, so the capture efficiency is low.

Summary of the invention

In order to solve the problem that the method for detoxifying fly ash by using a chelating agent including a digestate is poor in the treatment effect of high heavy metal fly ash. The invention relates to a waste incineration fly ash treatment agent, which combines an activation component and a composite diacid salt, and the activated component reduces the reactivity of calcium ions and magnesium ions by activating the reaction activity of heavy gold ions during the treatment process to make the composite compound The diacid salt can fully react with heavy metal ions, greatly enhancing the heavy metal capture efficiency of the composite diacid salt. The compound pity salt is a mixture of various piti compounds, including pity, dihydro acid dihydrogen salt and the like. The combination of the compounded acid salt and the active ingredient not only improves the efficiency of heavy metal capture, but also has the advantage of low cost. The invention relates to a waste incineration fly ash treatment agent, which comprises the following components: activation component, composite Phosphate component, solidification component (Sol idification) and auxiliary component, herein referred to as APS fly Ash treatment of harmless chemicals.

The technical solution adopted by the present invention is a waste incineration fly ash treatment agent containing the following components by weight: 20% _60% Active ingredient (Activation), 15% - 50% complex pity salt composition (Recombinant Phosphate) ), 20% - 50% curing component (Sol idification), 1% - 5% auxiliary component;

The activation component (Activation) contains the following components by weight: 40%_70% Ca (0H) ₂ , 20% _50% baking soda, 10% _30% baking soda;

The composite phosphorate component (Composite Phosphate) contains the following components by weight: 70% _90% sodium dihydrogen or sodium pate, 10% _30% sodium thiosulfate; The solidification molding component (Solidification) is a Portland cement;

The auxiliary component comprises the following components by weight: 20% _ 40% conventional dye, 60% _ 80% desiccant;

In the case of fly ash treatment, the fly ash is mixed with the fly ash treatment agent and water, and after being fully stirred and loaded and maintained for 24 hours to 48 hours, it is sent to the landfill for landfill; the ratio of the addition is by weight: fly ash is 100 parts, 10-30 parts of fly ash treatment agent, and 15-30 parts of water.

The invention has the beneficial effects that the APS fly ash treatment harmless chemical agent proposed by the invention has the effect of reducing the reactivity of the heavy gold ions during the treatment by the activation component and the composite diacid salt. The reactivity of calcium ions and magnesium ions enables the complex pity acid salt to fully react with heavy metal ions, which greatly enhances the heavy metal capture efficiency of the composite pity acid salt. The treated fly ash can meet the pollution control standard of domestic waste landfill. (GB16889-2008) entry requirements; on the other hand, it also has a price advantage, fly ash processing costs are low. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing the process of detoxification treatment of an APS detoxifying agent proposed by the present invention. detailed description

A waste incineration fly ash treatment agent containing the following components by weight: 20% _60% activation component (Activation), 15%-50% composite Phosphate component, 20% - 50% curing molding component (Sol idification ) , 1% - 5% auxiliary component; The activation component (Activation) contains the following components by weight: 40%_70% Ca (0H) ₂ , 20% _50% baking soda, 10% _30% small soda;

The composite phosphorate component (Composite Phosphate) contains the following components by weight: 70% _90% sodium dihydrogen or sodium pate, 10% _30% sodium thiosulfate;

The solidification molding component (Solidification) is a Portland cement;

The auxiliary component contains the following ingredients by weight: 20% to 40% conventional dye, 60% to 80% desiccant.

Fig. 1 is a flow chart showing the process of harmless treatment of waste incineration fly ash by using APS fly ash treatment harmless chemical agent proposed by the invention. The figure shows that when the fly ash treatment is carried out, the APS fly ash is added to the fly ash to treat the harmless chemical and water. After fully stirring, and then the vehicle is cured for 24 hours to 48 hours, the fly ash can be sent to the landfill. Field landfill; the ratio of addition is by weight: 100 parts of fly ash, 10-30 parts of APS fly ash treatment, and 15-30 parts of water.

Experiments have shown that the harmless treatment of the APS harmless chemical proposed by the present invention has the following advantages:

(1) Effectively overcome the handling problems of high-weight metal fly ash.

The existing fly ash treatment technology is difficult to overcome the high heavy metal content fly ash. Taking lead (Pb) as an example, the lead leaching toxicity of the original urban fly ash is mostly 1-5 mg/L, while some industrial developed cities such as Shenzhen and Suzhou are due to Domestic garbage contains a large amount of industrial waste, and the heavy metal content is much higher than that of ordinary cities. The lead element Shenzhen Baoan is as high as 50-100 mg/L ₀ and the Domestic Waste Landfill Pollution Control Standard (GB 16889 - 2008) lead leaching toxicity index It is 0.25 mg/L, and the removal efficiency of high-weight metal fly ash is more than 99%. This efficiency is difficult to achieve with fly ash treatment technology. The technology can be applied to the above high-heavy metal content fly ash, and the average removal efficiency of high-heavy metal elements can reach: Copper 99%, cadmium 99. 67%, lead 99. 87%, zinc 99. 96%, cadmium 99. 67%. It proves that the technology can maintain effectiveness and stability when used in high heavy metal fly ash.

(2) Has good economic value (taking the three waste-to-energy plants in Shenzhen as an example)

Economic analysis table

Note: The annual fly ash amount is calculated according to 8000h

As shown in the above table, the use of APS harmless technology, for the current situation of Nanshan waste-to-energy plant, can save processing costs of 8.8 million yuan per year, compared with the current chelating agent technology, can still save 800,000 yuan per year. For the current situation of Yantian Waste-to-Energy Plant, the annual processing cost can be saved by 4.95 million yuan, which can save 900,000 yuan per year compared with the current chelating agent technology. For the current situation of Baoan Waste Power Plant, the annual processing cost can be saved by 12 million yuan, which can save 3.6 million yuan per year compared with the current chelating agent technology. In total, the three plants can save 25.75 million yuan per year compared to the dangerous landfill, which saves 5.3 million yuan per year compared to the current chelating agent technology. In summary, the APS harmless technology reflects good economic benefits regardless of safe landfill or current chelating agent technology.

Claims

Claim

A waste incineration fly ash treatment agent comprising the following components by weight: 20% to 60% of an active ingredient, 15% to 50% of a compounded salt component, and 20% to 50% of a cured molding component , 1%-5% auxiliary ingredients;

The activated component contains the following components by weight: 40%-70% Ca (0H) ₂ , 20% _50% baking soda, 10% _30% baking soda; the composite pity salt component contains the following components by weight : 70%-90% sodium dihydrogen or sodium pate, 10%-30% sodium thiosulfate; the solidified molding component is Portland cement;

The auxiliary component contains the following ingredients by weight: 20%-40% conventional dye, 60%-80% desiccant.

2. The waste incineration fly ash treatment agent according to claim 1, wherein, in the fly ash treatment, a fly ash treatment agent and water are added to the fly ash, and the mixture is fully stirred and loaded for 24 hours-48. After the hour, the landfill is sent to the landfill; the mixing ratio is: by weight: 100 parts of fly ash, 10-30 parts of fly ash treatment agent, and 15-30 parts of water.