Industrial preparation method for preparing sodium hydrogen carbonate for smoke purification from waste alkali

Abstract

The invention discloses an industrial preparation method for preparing sodium hydrogen carbonate for smoke purification from waste alkali. The method is a process for preparing a sodium hydrogen carbonate product from Na2SO4 obtained by performing circulating washing and clarifying a smoke mixture consisting of the waste alkali and flue gas. The waste alkali is a drying solid and comprises the following components in percentage by weight: 50-85 percent of Na2CO3, 12-35 percent of Na2SO4 and 1-15 percent of others; the waste alkali is caprolactam combustion waste alkali or sodium carbonate waste alkali. The method is reasonable in design; the aims of treating waste gas by the waste alkali and treating waste by waste are achieved; furthermore, the sodium hydrogen carbonate product with relatively high value can be obtained by the method, so that energy is saved, and pollution is reduced; moreover, the smoke purification cost is lowered, and secondary pollution caused by smoke purification is avoided; pollution caused by the waste alkali to the environment is thoroughly solved, and the social benefit is very obvious.

Description

technical field [0001] The invention relates to an industrial preparation method for preparing sodium bicarbonate in flue gas purification from waste caustic soda, specifically relates to the preparation technology of sodium bicarbonate used in flue gas purification by waste caustic, and belongs to the field of flue gas purification. Background technique [0002] The continuous progress of petroleum and chemical industries has not only promoted economic development, but also caused pollution to the environment. At present, the global pollution problem has become increasingly serious, and has attracted widespread attention and attention from all over the world, especially coal-fired power plants. , coal-fired boilers, and waste incineration flue gas emissions, etc., have seriously polluted the atmosphere. We know that coal-fired flue gas contains a large amount of soot, carbon dioxide, SO 2 and NO X Among them, the carbon dioxide emitted by fuel combustion is the main substa...

AI Technical Summary

Problems solved by technology

[0004] Existing patent documents CN101570370 (method for high-resource treatment of cyclohexanone saponification waste lye, 2009-11-04) and CN102874848A (a method for recovering sodium bicarbonate and organic acid sodium salt from cyclohexanone waste lye) method, 2013-01-16) all disclose a production method for producing sodium bicarbonate by using waste lye, especially the patent document CN101570370, which discloses the use of cyclohexanone waste lye to react with carbon dioxide in flue gas to produce The method for obtaining sodium bicarbonate has achieved the process effect of using waste to treat waste and zero discharge, but it has been proved by practice that the quality of sodium bicarbonate obtained by this method is still in the crude product stage. If this method obtains sodium bicarbonate as an adsorbent As a purification process for flue gas desulfurization and denitrification, its removal effect is not ideal. At the same time, the crude product yield of sodium bicarbonate obtained by this method is low. Increase its industrial scale, but also increase the crude product purification process, which greatly improves the cost input of the entire preparation process. For this reason, the present invention emerges as the times require

Images