System capable of recovering flue gas waste heat for ultra-clean flue gas discharge and zero wastewater discharge of power plant

Abstract

The invention discloses a system capable of recovering flue gas waste heat for ultra-clean flue gas discharge and zero wastewater discharge of a power plant. The system comprises a dry-type electric precipitator, a low-temperature wet-type electric precipitator, a desulfurization tower, a spray drying tower, an air flue gas heat exchanger, a flue gas cooling heat exchanger, a flue gas reheater, anair reheater, a warm air heater, a bag dust collection device, a chimney, a first booster fan, a second booster fan and a circulating pump; the air flue gas heat exchanger and the flue gas cooling heat exchanger are connected in series on the flue gas side between the dry-type electric precipitator and the low-temperature wet-type electric precipitator; and the flue gas cooling heat exchanger communicates with the flue gas reheater, the warm air heater and the air reheater and through a heat medium water conveying pipe and a circulating pump respectively. A waste water evaporation and zero emission system for ultra-clean flue gas emission and white smoke elimination is coupled, low-cost waste heat resources are adopted to reduce the energy cost of a waste water zero emission system, the reliability and stability of the system are improved, and the overall investment and operation cost are reduced.

Description

technical field [0001] The invention relates to the technical field of energy saving and emission reduction in coal-fired power plants, in particular to a system for recovering waste heat from flue gas for ultra-clean emission of flue gas and zero emission of waste water in power plants. Background technique [0002] As the country's environmental protection standards become more and more stringent, the voice of the society for the implementation of zero discharge of waste water from thermal power plants is also increasing; at the same time, the national environmental protection regulations, regardless of new power plants or power plants that have been put into operation, will not approve hydraulic power plants in the future. Ash removal system and wet ash field, so the desulfurization wastewater will face a new situation where there is nowhere to reuse it. The treatment technology of high-concentration saline wastewater at the end of the power plant will become the key to re...

AI Technical Summary

Problems solved by technology

At present, the evaporation crystallization technology is relatively mature, with the widest application range and high system reliability, but the evaporation energy consumption and operating costs are large

The flue spraying method has attracted more and more attention from the thermal power industry due to its cost advantage. However, as environmental protection standards become stricter, in the long run, whether this method is appropriate for the disposal of solids is still somewhat controversial

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