Desulfurization, denitrification and dust removal ultralow emission process and system for production of cement from low-sulfur raw materials

Abstract

The invention discloses a desulfurization, denitrification and dust removal ultralow emission process and system for production of cement from low-sulfur raw materials. The process comprises the stepsas follows: firing of cement clinker, dust removal, flue gas blending, low-temperature SCR denitrification and wet desulfurization. The system comprises a cement clinker firing system, a kiln tail high-temperature fan, a grinding system, a kiln tail dust collector, a low-temperature SCR denitrification reactor, a wet desulfurization tower, a kiln head dust collector and a kiln head induced draftfan; a kiln tail preheater C1 gas outlet, the kiln tail high-temperature fan, the grinding system, the kiln tail dust collector, the low-temperature SCR denitrification reactor, the wet desulfurization tower, an exhaust fan and a kiln tail chimney are sequentially arranged; a cooler, a kiln head dust collector and the kiln head induced draft fan are sequentially connected; an outlet of the kiln head induced draft fan is connected with a gas outlet of the kiln tail dust collector. Dry desulfurization, SCR and wet desulfurization processes are adopted for production of cement from the low-sulfurraw materials, and desulfurization and denitrification ultralow emission during production of the cement from the low-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 from low-sulfur raw materials. Background technique [0002] The national environmental protection policy is becoming more and more stringent. The national standard GB4915-2013 "Cement Industry Air Pollutant Emission Standard" sets special restrictions on the emission of air pollutants from cement kilns and waste heat utilization systems in key areas as NO x 320mg / Nm 3 , SO 2 100mg / Nm 3 , Particulate matter 20mg / Nm 3 . The second generation cement technical standard released by the Building Materials Association requires 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 Emission i...

AI Technical Summary

Problems solved by technology

[0007] When producing cement from low-sulfur raw materials, low-sulfur here refers to SO in raw materials 3 When it is 0.1-0.5%, the flue gas emission is easy to exceed the standard when the grinding is stopped. At this time, if the semi-dry desulfurization is set, the one-time investment cost is relatively large, and the frequency of use is small. Reduce the efficiency of the equipment, increase the energy consumption and power consumption of the system, and have a negative impact

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