Oxygen/carbon dioxide combustion technique applied to cement clinker production process

Abstract

The invention discloses an oxygen / carbon dioxide combustion technique applied to a cement clinker production process. The oxygen / carbon dioxide combustion technique comprises the following steps: cooling a clinker by a first path of air, feeding a first path of high-temperature fume as secondary air into a rotary kiln after clinker cooling, preheating a second path of high-temperature fume by a heat exchange device, introducing an O2 / CO2 gas of a decomposition furnace, and feeding into a waste heat boiler for waste heat power generation; feeding a second path of air into the rotary kiln through a combustor; feeding fume discharged from the tail end of the rotary kiln into a preheater I for preheating a raw material, and feeding fume discharged from the preheater I into the waste heat boiler; feeding fume discharged from the decomposition furnace into a preheater II for preheating the raw material; generating backflow fume of which the CO2 concentration is greater than 95% from the preheater II, mixing a part of the backflow fume with oxygen separated from a third path of air, preheating, feeding the mixed gas as an O2 / CO2 atmosphere for raw material decomposition into the decomposition furnace, and performing purification, dust collection and concentration on the other part of the mixed gas, thereby obtaining CO2 of which the concentration is greater than 99%. Compared with a conventional cement clinker production process, the cement clinker production process disclosed by the invention has the advantage that the emission amount of CO2 is reduced by 60-75%.

Description

technical field [0001] The invention relates to an oxygen / carbon dioxide combustion technology, in particular to an oxygen / carbon dioxide combustion technology applied to a cement clinker production process. Background technique [0002] CO 2 The greenhouse effect caused by it continues to intensify, and the cement industry is CO 2 sources of high emissions, the CO emitted by 2 Accounting for about 5% of total emissions from industrial production, cement kilns CO 2 Emissions mainly come from the decomposition of carbonate in raw meal and combustion of pulverized coal, of which the decomposition of carbonate in raw meal accounts for about 60%. The CO2 emitted per 1kg of cement production is about 0.6kg-0.7kg, and the CO2 in the cement industry 2 The emissions are second only to the power industry, with CO 2 Emission reduction is urgent. [0003] Cement industry CO 2 Emission reduction technologies mainly include fuel substitution, improving heat transfer efficiency and...

AI Technical Summary

Problems solved by technology

The "adopting O 2 / CO 2 Combustion technology enriches CO 2 Cement clinker production process", this process is very difficult to fully realize under the current conditions, this process requires the cement kiln to be completely sealed, which cannot be satisfied under the current production conditions; secondly, in this process, O 2 / CO 2 The combustion situation is different from the traditional air combustion situation, and the cement kiln design needs to be completely updated, including the rotary kiln, cooler, burner, preheater, calciner and even refractory materials, etc.

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