Desulfurization denitration dedusting ultra-low discharge process and system for producing cement from high-sulfur raw materials

Abstract

The invention discloses a desulphurization denitration dedusting ultra-low discharge process and system for producing cement from high-sulfur raw materials. The process comprises the steps of cement clinker firing, coarse dedusting, semi-dry desulphurization, fine dedusting, desulphurization ash treatment, flue gas blending and low-temperature SCR denitration. The system comprises a cement clinkerfiring system, a kiln tail high-temperature fan, a grinding system, a first dust collector, a semi-dry desulphurization tower, a second dust collector, a low-temperature SCR denitration reactor, a kiln head dust collector and a kiln head induced draft fan. A gas outlet of the kiln tail preheater C1, the kiln tail high-temperature fan, the grinding system, the first dust collector, the semi-dry desulfurization tower, the second dust collector, a relay fan, the low-temperature SCR denitration reactor, an exhaust fan and a kiln tail chimney are sequentially connected and arranged; an air outletof a cooler, the kiln head dust collector and the kiln head induced draft fan are sequentially connected; and the outlet of the kiln head induced draft fan is connected with a gas outlet of the seconddust collector. According to the invention, a semi-dry desulfurization and low-temperature SCR denitration process is adopted, so that ultra-low discharge of desulfurization, denitration and dedusting for producing the cement from the high-sulfur raw materials is realized.

Description

technical field [0001] The invention relates to the technical field of flue gas treatment, in particular to an ultra-low emission process and system for desulfurization, denitrification and dust removal for producing cement with high-sulfur raw materials. Background technique [0002] The national environmental protection policy is becoming more and more strict. The national standard GB4915-2013 "Air Pollutant Emission Standard for Cement Industry" has special restrictions on the emission of air pollutants from cement kilns and kiln tail waste heat utilization systems in key areas. x 320mg / Nm 3 , SO 2 100mg / Nm 3 , particulate matter 20mg / Nm 3 . NO x Emission is 100mg / Nm 3 , SO 2 Emission is 50mg / Nm 3 , dust emission is 10mg / Nm 3 . Recently, some local governments have introduced stricter policies to limit unit emissions and total emissions NO. x Emission is 50mg / Nm 3 , SO 2 Emissions are 35mg / Nm 3 , dust emission is 5mg / Nm 3 . Cement manufacturers either add ...

AI Technical Summary

Problems solved by technology

[0006] The joint desulfurization and denitrification technology has problems such as high fixed investment, complicated process, complicated operation and high operation and maintenance costs

The flue gas desulfurization and denitrification integrated technology has been researched on simultaneous desulfurization and denitrification in the same device, such as using activated carbon, ozone, etc., but there are disadvantages such as high operating costs of adsorbents, poor equipment reliability, and high requirements for reaction temperature windows. , it is difficult to meet the needs of large-scale industrial use; the technology of iron and steel, metallurgy, coking industry and other industries is not suitable for cement high dust industry

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