Steel slag composite desulfurizer for desulfurizing pulverized coal during combustion and desulfurization method using same

Abstract

The invention provides a steel slag composite desulfurizer for desulfurizing pulverized coal during combustion, which comprises 50 to 100 parts by weight of steel slag, 45 to 85 parts by weight of limestone and 21 to 37 parts by weight of alumina; and the steel slag composite desulfurizer also comprises the following components: 37 to 45 percent by weight of calcium oxide, 8 to 24 percent by weight of alumina, 4 to 14 percent by weight of ferric oxide and 3 to 11 percent by weight of silicon oxide. The steel slag composite desulfurizer adopts the industrial waste steel slag and the limestone as main materials, and the mixture of alumina powder, which contains the calcium oxide, the alumina, the ferric oxide and the silicon oxide is added, a high-calcium-to-sulfur ratio and low-heat consumption formula is adopted, high sulfur fixation efficiency (60 to 80 percent) is achieved, and after desulfurization during combustion, sulfur-fixed slag can be directly recycled as cement clinker substitute for recycling. The invention also provides a desulfurization method using the steel slag composite desulfurizer.

Description

technical field [0001] The invention relates to a desulfurizer used in boilers and pulverized coal combustion furnaces in the power generation industry, in particular to a steel slag composite desulfurizer and a desulfurization method using the desulfurizer. Background technique [0002] For a long time, the desulfurization research of high-sulfur coal has been an important topic in the research of environmental pollution control, and the high-efficiency desulfurization technology has also been a research hotspot for coal and environmental workers. According to the statistics of the U.S. Environmental Protection Agency, SO 2 There are more than 200 kinds of control technologies. Among them, the combustion desulfurization method has attracted the attention of many researchers because it does not need to add additional desulfurization equipment and saves investment. Combustion desulfurization method of pulverized coal, that is, adding a certain desulfurizer to the coal, so t...

AI Technical Summary

Problems solved by technology

But in reality, calcium sulfate is the main sulfur-containing ore phase, and it will decompose below 1100°C under the combustion condition of pulverized coal, so the sulfur fixation efficiency is usually lower than 50%.

In addition, the calcium-sulfur ratio currently controlled during combustion desulfurization is generally 2 to 3, and the main mineral phases in the desulfurization product (sulfur-fixing slag) are calcium sulfate, calcium aluminum feldspar, calcium aluminate, dicalcium silicate, free oxide ( Calcium oxide, silicon oxide or aluminum oxide), etc., due to changes in coal ash composition and fluctuations in combustion conditions, the mineral phase composition of sulfur-fixed slag changes greatly, and there are many free oxides. Except for being used as general fly ash, it is basically No direct resource utilization