Desulphurization process by combining printing and dyeing wastewater

Abstract

The invention discloses a desulphurization process by combining printing and dyeing wastewater. Carbide slag, lime or lime stone serving as a desulphurizer is adopted to desulphurize fume by a wet method; and the water adopted in the pulping process for preparing desulphurization pulp from the desulphurizer is the printing and dyeing wastewater, wherein the mass content of solids in the desulphurization pulp is 8 to 15 percent, the pH value of the desulphurization system is 5.2 to 6.0, and the liquid-air ratio is 8 to 12L/m<3>. In the desulphurization process, the mixed pulp of the carbide slag and the printing and dyeing wastewater serves as the desulphurizer to treat the fume by the wet method; the discharging amount of the printing and dyeing wastewater is greatly reduced; the COD removing rate in the high-concentration wastewater of which the concentration is over 10,000mg/L is over 80 percent; the colour removing rate is over 90 percent; and the discharging amount of the wastewater is reduced by over 30 percent.

Description

technical field [0001] The invention belongs to the fields of water pollution control and air pollution control, and specifically relates to a desulfurization process utilizing the mixed complementary characteristics of desulfurizer and printing and dyeing wastewater. Background technique [0002] With the rapid development of the textile industry, the textile industry has become one of the largest portals for the discharge of industrial wastewater in my country, and the discharge of printing and dyeing wastewater accounts for 80% of the textile industry wastewater. National printing and dyeing wastewater discharge is about 3-4 million m 3 / day, of which Zhejiang, Jiangsu, Guangdong, Shandong and Fujian account for about 80% of the total output. Printing and dyeing wastewater has the characteristics of complex organic components, high concentration, many refractory substances, large water volume, high alkalinity, high COD, and strong pollution. [0003] Before the 1980s, t...

AI Technical Summary

Problems solved by technology

Since calcium hydroxide, the main component of calcium carbide slag, is an intolerant substance, its saturated solubility in water is only 22.8mmol/L. During the reaction with flue gas, the rapidly consumed OH - The ions cannot be replenished in time, r

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