System and method for ultralow volatile carbon-based fuel and lignite low-NOx blending combustion

Abstract

The invention discloses a system and a method for lignite and ultralow volatile carbon-based fuel low-NOx blending combustion. The system comprises a lignite drying system consisting of a crusher, a drying box, a small-particle-size drying lignite bin, a large-particle-size drying lignite bin, a steam pump, a tail gas purifying unit, a hot smoke pipe, a steam pipe and the like, and a ultralow volatile carbon-based fuel and drying lignite blending combustion system consisting of a fan coal mill, an ultralow volatile carbon-based fuel powder bin, fuel nozzles, a combustor secondary wind nozzle, an over fire air nozzle, a superheater, a tail flue, a coal economizer, an air preheater, a dust remover, a desulfurization device, an over fire air pipe and the like. A lignite drying technology is organically combined with the ultralow volatile carbon-based fuel and drying lignite blending combustion system, so that lignite is safely and effectively used, the problem of difficult ignition and burnout of ultralow volatile carbon-based fuels is solved, and NOx emission is reduced. The system is economical, environmentally friendly, simple, reliable, wide in application range and broad in application prospect.

Description

technical field [0001] The invention belongs to the field of lignite upgrading and high-efficiency clean utilization of coal, in particular to an ultra-low volatile carbon-based fuel and lignite with low NO x Systems and methods for blending. Background technique [0002] At present, the cascade utilization of coal is one of the important ways of clean and efficient utilization of coal. The by-products of coal pyrolysis and gasification, semi-coke and residual carbon, are burned as high-grade clean fuels to generate electricity, which is an important part of realizing clean and efficient cascade utilization of coal. With the rapid development of my country's coal chemical industry, there are a large number of such fuels that need to be burned and utilized urgently. However, the volatile content of pyrolysis semi-coke and gasification residue (hereinafter referred to as "ultra-low volatile carbon-based fuel") is very low, usually the volatile content of pyrolysis semi-coke ...

AI Technical Summary

Problems solved by technology

However, lignite has a high moisture content (full moisture is about 25-60%) and low calorific value, which leads to low thermal efficiency of direct combustion and high greenhouse gas emissions; meanwhile, lignite has a volatile content of more than 40%, which is easy to weather and crack Oxidation spontaneous combustion, difficult to store and large-scale development and utilization

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