Catalyst anti-ash-blocking technology based on arrangement of SCR denitration reactor in coal-fired boiler

Abstract

The invention provides a catalyst anti-ash-blocking technology based on arrangement of an SCR denitration reactor in a coal-fired boiler, which comprises a hearth, a boiler air supply outlet is arranged at the lower part of the hearth, a return feeder is connected above the boiler air supply outlet and at the lower part of the hearth, a separator is arranged above the return feeder, one side of the separator is connected to the upper part of the hearth, and the other side of the separator is connected to the lower part of the hearth. The other side of the separator is connected with a smoke exhaust pipeline, a high-temperature superheater, a low-temperature superheater, a high-temperature economizer, an SCR catalyst module, a low-temperature economizer, a primary air-air early warning device and a secondary air-air early warning device are sequentially arranged in the smoke exhaust pipeline, and a boiler smoke exhaust port is formed in the tail end of the smoke exhaust pipeline. The device can intercept large particles on each heating surface of the tail part during operation of the coal-fired boiler, prevent the SCR denitration catalyst from being arranged in the boiler from being blocked, scatter a large amount of accumulated dust falling in a clustered manner during soot blowing on each heating surface of the tail part of the coal-fired boiler, and prevent the accumulated dust falling to the surface of the catalyst from being accumulated to cause blockage.

Description

technical field [0001] The invention relates to the technical field of smoke and dust denitrification, in particular to a catalyst anti-clogging ash technology based on an SCR denitrification reactor arranged in a coal-fired boiler furnace. Background technique [0002] Flue gas desulfurization and denitrification technology is a boiler flue gas purification technology applied in the chemical industry that produces many nitrogen oxides and sulfur oxides. Nitrogen oxides and sulfur oxides are one of the main sources of air pollution. Therefore, the application of this technology has many benefits for ambient air purification. Strict desulfurization and denitrification processes are also required when coal-fired boilers emit dust. The main reasons for clogging and clogging are: first, large particles block the protective mesh of the catalyst, and when the clogging amount is large, fly ash deposits and accumulates. Hardening and falling off (blocky, low hardness); b, high-tem...

AI Technical Summary

Problems solved by technology

Therefore, the application of this technology has many benefits for ambient air purification. Strict desulfurization and denitrification processes are also required when coal-fired boilers emit dust. The main reasons for clogging and clogging are: first, large particles block the protective mesh of the catalyst, and when the clogging amount is large, fly ash deposits and accumulates. Hardening and falling off (blocky, low hardness); b. High temperature fly ash is sintered on the furnace wall and heating surface and falls off (flaky, high hardness); c. Furnace wall refractory material, insulation cotton flue gas washes and falls off fragments

The second is that when soot blowing is performed on the heating surface of the tail of the coal-fired boiler (high-temperature superheater, low-temperature superheater, high-temperature economizer, etc.), a large amount of ash accumulates in agglomerates and falls off, and falls to the surface of the catalyst to accumulate and cause blockage;

[0003] Hazards of large particles of smoke and dust accumulation: a. Flue gas drift, local smoke velocity rises sharply, catalyst local erosion wears intensified, and catalyst mechanical and chemical life is reduced; b. The effective contact area of ​​the catalyst is greatly reduced, and the denitrification efficiency is greatly reduced. The amount of denitrification agent (ammonia water, gaseous ammonia, urea) is significantly increased, and the escape of ammonia is increased; c. In severe cases, the catalyst is blocked, causing the boiler to fail to operate; d. In severe cases, the environmental protection index (Nox) exceeds the standard. In view of this We propose a catalyst anti-clogging ash technology based on the arrangement of SCR denitrification reactors in coal-fired boilers to solve the above problems

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