Method for controlling ammonia-process desulfurization aerosol discharge and dedicated absorption tower thereof

Abstract

A method for controlling ammonia-process desulfurization aerosol discharge is a method for controlling the aerosol discharge in an ammonia-process flue gas desulfurization technology, and comprises the steps: flue gas subjected to spray temperature reduction and cooled to 100-120 DEG C by atomized water is introduced to a desulfurization zone of a desulfurization absorption tower, flue gas from bottom to top in the desulfurization zone is subjected to countercurrent contact with a desulfurization liquid sprayed from top to bottom so as to absorb SO2 in the flue gas, and a packing or a sieve plate is arranged in the desulfurization zone; the flue gas enters a packing washing zone after desulfurization, and washing water is injected to remove coarse-grained aerosol generated in ammonia-process desulfurization; then the treated aerosol enters a water vapor phase transformation zone, vapor is injected from the middle part of the water vapor phase transformation zone, a supersaturated water vapor environment needed by water vapor phase transformation is established, and fine-grained aerosol micro-particles which are not removed are congealed, grow up and are removed from a silk screen mist eliminator at a flue gas outlet of the water vapor phase transformation zone; and the purified flue gas is discharged through a chimney from a flue gas outlet at the top of the desulfurization absorption tower. The method can effectively solve the discharge problem of the aerosol in the ammonia-process flue gas desulfurization. The invention discloses the dedicated desulfurization absorption tower of the method.

Description

technical field [0001] The invention relates to a method for controlling fine particles in coal-fired flue gas, in particular to a method for controlling aerosol in flue gas desulfurization by ammonia method. Background technique [0002] In recent years, the ammonia-based flue gas desulfurization process has been gradually popularized in coal-fired power plants due to its fast gas-liquid or gas-gas reaction speed, high desulfurization efficiency, and recyclable desulfurization by-products. It has become a technical bottleneck affecting the popularization and application of ammonia desulfurization process. Generally, the aerosol particles formed in ammonia desulfurization are mainly sub-micron particles from the quantitative point of view, but from the mass concentration distribution, the particles are mainly micron and larger than 10 μm, and the particle concentration after desulfurization can be increased several times compared with that before desulfurization to more tha...

AI Technical Summary

Problems solved by technology

However, under the existing ammonia desulfurization operating conditions, it is difficult to achieve the supersaturated water vapor environment required for the condensation and growth of aerosol particles; the selection of desulfurization operating conditions also mainly focuses on improving the desulfurization efficiency, and does not involve reducing the formation of aerosols

The Chinese invention patent with the application number 201010557866.4 proposes a method of using flue gas to achieve supersaturation in the desulfurization process and adding steam to the desulfurized clean flue gas to achieve supersaturation to promote the removal of ammonia-based aerosols. Supersaturation is reached during the desulfurization process, and the flue gas needs to be close to saturation before entering the desulfurization tower. It is not easy to realize the single-tower process without a pre-scrubber; simply adding steam to the desulfurized flue gas will cause a lot of water vapor to condense at the micron level The above coarse particles, and this part of the particles can be removed by conventional dust removal (fog removal) methods without condensation and growth.

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