Novel efficient flue gas desulfurization agent and method for treating desulfurization agent

Abstract

The invention provides flue gas desulfurization (FGD), refers to desulfurization of gas generated by combustion and belongs to tail management flue gas desulfurization. An FGD method technology is relatively developed; even if the desulfurization rate can be up to 90%, the process is complicated and the operation cost is high, and byproducts are difficult to treat. More flue gas desulfurization methods, including a wet method, a dry method and a semi-dry method, exist. Separated waste liquid obtained by carrying out alkali treatment on straws is used, and the waste liquid is used for the flue gas desulfurization and then is mixed with coal powder to form coal slurry to be used as fuel which is completely utilized. On the one hand, residual alkali, alkali lignin and lignin sulfonate in the waste liquid, and SO2 in flue gas are reacted to form a stable structure, and sulfur generated by combusting coal is removed; on the other hand, the residual alkali and oxides are separated from the waste liquid and are reacted with sulfur in the coal to be oxidized into stable sulfate ions, so that the sulfur fixation effect is realized.

Description

technical field [0001] The present invention starts from making full use of straw resources, uses alkali to treat straw waste liquid, the waste liquid contains alkali lignin and lignosulfonate reacts with sulfur ions to form a stable structure, and removes sulfur produced in coal combustion; separates waste liquid The residual alkali and oxides react with the sulfur in the coal and oxidize into stable sulfate ions, which play the role of sulfur fixation. And the added CaO also participates in the SO 2 The absorption process further improves the flue gas desulfurization rate. Due to the high content of organic matter in the desulfurizer, which is rich in calorific value, it absorbs SO 2 The desulfurizer can be mixed with pulverized coal to make coal water slurry, which is pumped into the furnace for combustion and utilization. The CaO that has not participated in the reaction can react with the sulfur removed from the black liquor during the combustion process to form CaSO 4...

AI Technical Summary

Problems solved by technology

The use of straw to produce fuel ethanol has attracted more and more attention. However, due to the complex composition of straw, various pretreatments are usually required on the straw raw materials. The pretreatment process technology is immature, and the waste liquid cannot be treated. The price of cellulase for fermentation High, making the production cost high and difficult to promote;

[0005] (3) Straw as energy: Although crop straw has been used as fuel for a long time, it is usually used for cooking, heating or even burned in farmland. It is in a low-efficiency utilization state, and the conversion rate is only 10% to 20%.

Alkaline pulping is commonly used in my country's papermaking industry. About 70% of the solids in the cooking black liquor are organic matter, and the lignin is a biomass rich in calorific value. Generally, most of the wood pulp black liquor uses alkali recovery to recover heat. Power generation or steam reuse, but the investment is huge, and straw pulping alkali recovery has problems such as low alkali recovery efficiency, poor efficiency, silicon interference, etc., making straw pulping a thing of the past

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