Helical airflow type wet method flue gas desulfurization process and spraying tower thereof

Abstract

The invention provides a swirling air flow-type and wet flue gas desulfurization technique and a spraying tower thereof. The technique guides flue gases to enter tangentially from the upper part of a spraying tower shell; the flue gases swirl inside the spraying tower shell and leave tangentially from the lower part of the spraying tower shell; at the same time, limestone grout is sprayed upward and fog drips of the grout firstly touch the downward-swirling flue gas reverse flow, and then fall back owing to the effect of self-weight and drag force of the flue gas and then touch the forward flow of the flue gas, thus sulfur dioxide in the flue gases is absorbed owing to the quick chemical reaction with limestone grout fog drops. The spraying tower comprises a spraying tower shell; the spraying tower shell is provided with tangentially arranged flue gas inlet and outlet channels; a spraying device for spraying absorbing agents upwards is arranged between the flue gas inlet and outlet channels; a central tank is arranged in the center of the spraying tower shell; a flue gas guide plate showing a spiral descent structure is arranged on the central tank; a defroster is arranged in the flue gas inlet and outlet channels of the spraying tower shell. The desulfurization efficiency thereof is high, investment is small, and operation is safe and reliable.

Description

technical field [0001] The invention relates to a limestone-gypsum wet flue gas desulfurization technology, in particular to a spiral air flow wet flue gas desulfurization technology and a spray tower. Background technique [0002] The acid rain problem is one of the global environmental problems facing mankind today. The sulfur oxides SO produced by coal burning 2 And nitrogen oxides NO pollution is the main protozoa of acid rain in my country. Since my country's energy structure is dominated by coal, in my country's power industry, thermal power has always accounted for about 70% of the total power generation, and coal-fired power plants are the largest source of air pollution in my country. Controlling the flue gas pollution of power plants is the requirement to realize the coordinated development of economy, society and environment, and it is also the requirement to give full play to the advantages of my country's coal reserves and realize the sustainable development of...

AI Technical Summary

Problems solved by technology

[0004] In order to ensure the desulfurization efficiency, full contact between the flue gas and the slurry is required, which requires the installation of multi-layer spraying devices, multi-layer demisting devices and other equipment in the spray tower to ensure a certain amount of flue gas and absorbent slurry droplets in the reaction zone. These factors will cause the tower body of the spray tower to increase, resulting in the consumption of a large amount of electric energy to lift the absorbent slurry from the bottom of the spray tower to the inlet of the spray device

Moreover, the flue gas in the existing spray tower flows from bottom to top, while the absorbent slurry droplets spray from top to bottom, and the two are in a 180° countercurrent contact state. Under the gravity and absorption of the absorbent slurry droplets Under the rectification effect of the agent slurry droplets on the flue gas, the flow resistance of the flue gas is very large, and a booster fan with a large power is required

In addition, the top of the existing spray tower adopts a frustum-shaped structure, and the cross-section of the outlet flue adopts a rectangular structure. This design and layout consumes a lot of materials but the overall rigidity is not strong. Usually, it is necessary to add a large number of reinforcement structures on the top of the tower. On the one hand, this increases the weight of the equipment, which is not good for the safe operation of the equipment. On the other hand, the support structure of the outlet flue at the top of the tower is relatively complicated, which is not conducive to the uniform distribution of the flue gas flow field, resulting in increased pressure loss of the flue gas flow, and the equipment Increased operating costs

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