Difference of ejector in dry desulfurization and wet desulfurization

The ejector is different in dry desulfurization and wet desulfurization. The main components of dry and semi-dry desulfurizers are emulsion desulfurizers (calcium hydroxide) made of quicklime and water. The flue gas is sprayed in countercurrent or downstream, and the generated gypsum is desulfurized after dust removal and solid recovery. Generally speaking, the desulfurization efficiency of ejector in dry and semi-dry desulfurization is very low, and the general desulfurization efficiency can only reach about 70%.

There are many kinds of injectors in wet desulfurization. The general principle is that after the flue gas is washed by alkaline solution, the SO2 in the flue gas is absorbed by the solution, and the sulfite solution is oxidized to sulfate after it is nearly saturated, and the desulfurization by-product is crystallized. Sulfite is also reduced to produce sulfur, which is filtered to obtain by-product sulfur. The efficiency of wet desulfurization is very high, which can reach 100% regardless of desulfurization cost. However, for absorbents such as ammonia desulfurization, the amount of ammonia escaping increases and nitrogen oxides destroy the atmosphere, so it is not advisable to simply pursue desulfurization! At the same time, corrosion is inevitable, which is the biggest problem in desulfurization industry and is also difficult to overcome so far. The reason of corrosion is that the composition of flue gas can be very complicated, the generated sulfate is strong acid under acidic conditions, chloride ions brought by flue gas will corrode stainless steel, fluoride ions will corrode glass (instrument), and alkaline substances added in desulfurization will also corrode steel. These two methods have their own advantages and disadvantages. Compared with dry desulfurization, the ejector is more likely to be blocked and cleaned every three months.