Desulfurization requirements
The large-scale desulfurization device that desulfurizes the flue gas of the desulfurization tower is called a desulfurization tower, while the small desulfurization and dust removal devices used for the flue gas desulfurization of coal-fired industrial boilers and kilns are mostly called desulfurization dust collectors. In the desulfurization tower and desulfurization dust collector, the flue gas containing SO2 should be chemically absorbed for the SO2 in the flue gas. In order to strengthen the absorption process, improve desulfurization efficiency, and reduce equipment investment and operating costs, desulfurization towers and desulfurization dust collectors should meet the following basic requirements:
(1) There is a large contact area between gas and liquid and
a certain contact time;
(2) The gas-liquid disturbance is strong, the absorption resistance is small, and the absorption efficiency of SO2 is high;
(3) The operation is stable, and there must be suitable operation flexibility;
(4) The pressure drop when the airflow passes through should be small;
(5) Simple structure, convenient manufacture and maintenance, low cost and long service life;
(6) No scaling, no clogging, wear resistance, corrosion resistance;
(7) Low energy consumption and no secondary pollution.
In the process of SO2 absorption and purification, low-concentration SO2 flue gas is treated, and the amount of flue gas is considerable. It is required to continuously and efficiently purify flue gas in an instant. Therefore, the chemical reactions that SO2 participates in should be extremely fast reactions, their intra-membrane conversion coefficient values are large, and the reaction occurs in the membrane, so the absorption tower with the gas phase as a continuous phase, a high degree of turbulence, and a large phase interface is selected as the desulfurization tower. It is more suitable for desulfurization and dust collector. Usually, spray towers, packed towers, spray towers, tray towers, Venturi absorption towers, etc. can meet these requirements. Among them, the spray tower is one of the most widely used types of desulfurization towers. The spray tower has the advantages of simple structure, mature and reliable technology, and is widely used in large power plants, small and medium-sized low-sulfur flue gas treatment; for high-sulfur flue gas treatment, The non-ferrous industry is dominated by pneumatic emulsification desulfurization towers and multi-layer spray towers.