A kind of garbage fly ash heavy metal stabilizer and using method thereof

Abstract

The invention discloses a novel waste fly ash heavy metal stabilizer. The novel waste fly ash heavy metal stabilizer is prepared from, by weight, 5-7 parts of a phosphate compound, 2-5 parts of light calcined magnesia, 1-3 parts of a sulfhydryl-type chelating agent, 1-3 parts of thiuram, 1-3 parts of modified sodium bentonite and 1-2 parts of a homogenizing agent. According to the novel waste fly ash heavy metal stabilizer, the phosphate compound can react with heavy metal under a certain pH condition to generate stable heavy metal mineral salt, the light calcined magnesia has a good PH buffering function and heavy metal absorbing capability and cooperates with the phosphate compound to achieve the effect of removing heavy metal in fly ash accordingly, the chelating capability of the chelating agent is high, the added modified sodium bentonite is formed by compounding rice husk ash and sodium bentonite, the specific surface area of the rice husk ash is large, and a porous structure is formed after the specially treatment of a dilute phosphoric acid solution and a ferric chloride solution.

Description

technical field [0001] The invention relates to the technical field of garbage fly ash treatment, in particular to a garbage fly ash heavy metal stabilizer and a use method thereof. Background technique [0002] Fly ash is the residue collected from the flue gas purification system of the waste incineration plant. The hazards are the greatest; the toxicity of fly ash is extremely harmful. It contains the most toxic inorganic substances "heavy metals" and the most toxic organic substances "dioxins". Fly ash contains the most toxic inorganic substances "heavy metals" The five most harmful heavy metals: lead, chromium, mercury, arsenic, and cadmium. These heavy metals cannot be decomposed in water, and combine with other toxins in water to form more toxic organic substances. The common harms of heavy metals to human body are: lead: harm human brain cells, cause carcinogenesis and mutagenesis, etc.; chromium: hexavalent chromium has strong oxidizing effect, so chronic poisonin...

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Problems solved by technology

[0003] Municipal solid waste incineration fly ash contains a large amount of heavy metal ions and organic pollutants. The existing heavy metal stabilizers are not effective in treating heavy metals in fly ash, and the dissolution rate of heavy metal substances is poor, so further improvement is still needed.

[0004] Chinese Patent Document Publication No. (CN108179277A) discloses a method for treating fly ash with high salt and heavy metal content, including: washing the fly ash with pickling solution, and controlling the liquid-solid ratio to maximize the soluble salt in the fly ash The concentrated brine with recovery value is obtained, and the obtained concentrated brine is returned to the process as a supplementary liquid after separation and recovery of salt to continue washing the next batch of fly ash; after washing, the fly ash is acid-leached with acid leaching solution, and through the control Liquid-solid ratio, so that the heavy metals in the fly ash can enter the leaching solution to the greatest extent, and the heavy metal leaching solution with recovery value can be obtained. The stage washing process removes residual heavy metal ions and incompletely leached heavy metals, so that the leaching toxicity of fly ash reaches the standard and realizes the harmlessness of fly ash. Poor, so still needs further improvement

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