Harmless disposal method for high-arsenic heavy metal sludge

A technology of heavy metal sludge and disposal method, which is applied in sludge treatment, chemical instruments and methods, fixed/solidified sludge treatment, etc. It can solve the problems of unstable leaching toxicity and high cost, and achieve good solidification effect and good storage conditions. The effect of relaxation and cost reduction

CN105693050AActive Publication Date: 2016-06-22YUNNAN COPPER CO LTD +2
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2016-06-22

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Abstract

The invention relates to a harmless disposal method for high-arsenic heavy metal sludge and belongs to the technical field of hazardous waste treatment. The harmless disposal method comprises the following steps of firstly, precalcining the high-arsenic heavy metal sludge with water content of less than 40 percent under the condition that the temperature is 100 to 300DEG C for 0.5 to 3 hours to obtain a calcined product; adding lime and additives into the obtained calcined product according to the mass ratio of (30 to 80): (10 to 40):(1 to 30), and uniformly stirring to obtain a mixed material; forming the obtained mixed material to produce a solidified body, cooling and then safely storing. According to the sludge disposed by the harmless disposal method, leaching concentrations of all heavy metal elements meet the requirements of Identification Standard and Leaching Toxicity Identification of Hazardous Waste (GB5085.3-2007) and Landfill Pollution Control Standard for Hazardous Waste (GB18598-2001).
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Description

Technical field

[0001] The invention relates to a harmless disposal method of high-arsenic heavy metal sludge, belonging to the technical field of hazardous waste treatment. Background technique

[0002] At present, non-ferrous heavy metal smelting is dominated by pyrometallurgical smelting, and heavy metal pyrometallurgical smelting mostly uses flue gas scrubbing to remove impurities in the flue gas, which will generate a large amount of acidic heavy metal wastewater. Such wastewater is passed through lime-iron salt. After treatment by method or neutralization method, it is converted into industrial water that meets the standard. Arsenic (As) and other heavy metal elements associated with heavy metal minerals will all enter the neutralization slag (arsenic-containing heavy metal sludge) through neutralization and precipitation. Therefore, the non-ferrous heavy metal smelting industry produces millions of tons of such heavy metal sludge every year. In the toxicity leaching experi...

Examples

Embodiment 1

[0021] Such as figure 1 As shown, the specific steps of the harmless disposal method of high-arsenic heavy metal sludge are as follows:

[0022] (1) Pre-calcining: First, the moisture content <40% high arsenic heavy metal sludge (the main physical and chemical properties of high arsenic heavy metal sludge are shown in Table 1 and the leaching toxicity is shown in Table 2), pre-calcined at a temperature of 300°C for 3 hours to obtain a calcined product;

[0023] Table 1

[0024]

[0025] (2) Ingredients: Add additives and lime to the calcined product obtained in step (1) according to a mass ratio of 80:12:8 to obtain a mixture; wherein the additives are two with a mass ratio of 40:20:20:10:10 Silicon oxide powder, bismuth trioxide (Bi 2 O 3 ), boron oxide (B 2 O 3 ), calcium oxide (CaO) and zinc oxide (ZnO) mixture; use planetary mixer for stirring;

[0026] (3) The mixture material obtained in step (3) is molded to produce a solidified body, which is stored safely after cooling; the ...

Embodiment 2

[0032] Such as figure 1 As shown, the specific steps of the harmless disposal method of high-arsenic heavy metal sludge are as follows:

[0033] (1) Pre-calcining: First, the moisture content <40% high arsenic heavy metal sludge (the main physical and chemical properties of high arsenic heavy metal sludge are shown in Table 3 and the leaching toxicity is shown in Table 4), pre-calcined at a temperature of 250℃ for 2h to obtain a calcined product;

[0034] table 3

[0035]

[0036] (2) Ingredients: Add additives and lime to the calcined product obtained in step (1) at a mass ratio of 75:17:8 to obtain a mixture material; where the additive is a mass ratio of 20:40:20:10:10 dioxide Silicon powder, bismuth trioxide (Bi 2 O 3 ), boron oxide (B 2 O 3 ), calcium oxide (CaO) and zinc oxide (ZnO) mixture; use planetary mixer for stirring;

[0037] (3) The mixture material obtained in step (3) is molded to produce a solid body, which is cooled and stored safely; in step (3), it is molded by h...

Embodiment 3

[0043] Such as figure 1 As shown, the specific steps of the harmless disposal method of high-arsenic heavy metal sludge are as follows:

[0044] (1) Pre-calcining: First, the moisture content <40% high arsenic heavy metal sludge (the main physical and chemical properties of high arsenic heavy metal sludge are shown in Table 5 and the leaching toxicity is shown in Table 6), pre-calcined at a temperature of 250°C for 1 hour to obtain a calcined product;

[0045] table 5

[0046]

[0047] (2) Ingredients: Add additives and lime to the calcined product obtained in step (1) according to the mass ratio of 70:20:10 to obtain a mixture material; where the additive is a mass ratio of 20:20:40:10:10 dioxide Silicon powder, bismuth trioxide (Bi 2 O 3 ), boron oxide (B 2 O 3 ), calcium oxide (CaO) and zinc oxide (ZnO) mixture; use planetary mixer for stirring;

[0048] (3) The mixture material obtained in step (3) is molded to produce a solidified body, which is stored safely after cooling; the ...