Method for neutralizing sulphur smelting waste by quick lime

Abstract

The invention relates to a method for neutralizing sulphur smelting waste by quick lime. The method comprises the following steps: (1) smelting the sulphur waste by an indigenous method; (2) carrying out treatment on the quick lime, wherein CaO content of the quick lime is not lower than 60 percent; (3) adding 0.1 to 1.0 percent of quick lime into the ground sulphur smelting waste, mixing and stirring, adding deionized water, preparing leachate and regulating the pH value of the leachate to 6.8 to 7.2; (4) carrying out treatment on the neutralized waste, wherein content of heavy metal ions in the neutralized sulphur smelting waste is obviously reduced, so that the property of the waste is changed to I-class general industrial solid waste from II-class general industrial solid waste. The neutralized waste can be used as an auxiliary material in cement production and a building material, and also can be transported to a waste concentrated treatment site which is built according to the requirements of the I-class general industrial solid waste treatment site to be subjected to concentrated treatment.

Description

technical field [0001] The invention relates to the disposal and utilization of sulfur smelting waste residues, and belongs to the field of comprehensive utilization of waste residues. Background technique [0002] Sulfur smelting slag is the slag produced when sulfur is smelted by the pyrite soil method. From the 1950s to the 1980s, my country followed the indigenous sulfur smelting production technology of the medieval production level. The resource utilization rate was extremely low, and the smelting recovery rate was only about 30%, and a large amount of sulfur and heavy metals remained in the smelting waste residue. At that time, about 70% of domestic sulfur demand came from indigenous sulfur smelting, and 7 to 8 tons of waste residue were produced for every ton of sulfur produced. Such a huge amount of sulfur smelting waste was expected to be disposed of. [0003] With the complete closure of thousands of "lime kiln" sulfur smelting furnaces, the 40-year history of su...

AI Technical Summary

Problems solved by technology

However, because the sulfur smelting area is generally far away from the cement plant, the transportation cost of waste residue is high, so it is limited as an auxiliary material for cement production

In addition, the sulfur smelting waste slag contains about 22% total iron. Using magnetic separation technology, 86% of Fe can be recovered from this slag, with a grade of 61.8%. It is about 450 yuan, and the market price of 60% iron-containing products per ton can only be sold at 450-500 yuan / ton without taxes, so it is useless to choose iron for this project

The tailings after iron separation are re-selected for titanium dioxide. The content of titanium dioxide in the product is 37-40%, and the content of ferric oxide is 27-34%. However, there is no sales market at present. It can be seen that a lot of work is still needed to achieve the comprehensive utilization of sulfur smelting waste slag

[0005] The monitoring results of leachate toxicity and corrosion identification of sulfur smelting waste residues show that the leaching monitoring values ​​of heavy metal hazardous wastes such as lead, cadmium, mercury, hexavalent chromium, and arsenic in the waste residue leachate are far lower than the corresponding hazardous waste leaching toxicity identification standards. It does not belong to hazardous waste, but the pH value is 3.0-4.8, which is strongly acidic and belongs to Class II general industrial solid waste

[0006] According to the Pollution Control Standard for General Industrial Solid Waste Storage and Disposal Sites (GB18599-2001), the site selection and anti-seepage requirements for Class II waste slag storage are relatively high, it is difficult to select a suitable storage site, and the construction investment is relatively high. Big

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