There are more companies with wet calcium desulfurization technology, Travertine Stone the reaction principle is the same, the main process differences are concentrated in the absorption tower structure on the different, such as the packing tower (now no use), liquid column tower, bubble tower and spray tower, One of the most widely used spray tower tower, the company's internal structure of the spray tower is also different, Travertine Stone the formation of their own technical characteristics, such as the tower set the metal tray, Travertine Stone pulp pool with disturbance pump and so on. Various types of absorption towers have their own characteristics, have more successful performance, the spray tower using nozzle atomization, flue gas and absorbent droplets convection contact, Travertine Stone both to ensure adequate absorption, and no tower fouling Worry, so the most common.
At present, the world's coal-fired power plant desulfurization process many, the application of these methods depends mainly on the boiler capacity and peaking requirements, Travertine Stone the type of combustion equipment, the type of fuel and sulfur content, desulfurization rate, Travertine Stone desulfurization agent supply conditions and The location of the power plant, the use of by-products and other factors.
According to the desulfurization process in the production of the different parts can be divided into: pre-combustion desulfurization (such as: coal washing desulfurization), Travertine Stone furnace combustion desulfurization (such as: circulating fluidized bed boiler and furnace spray calcium), Travertine Stone after burning desulfurization Flue gas desulfurization (such as: seawater desulfurization, Travertine Stone limestone - gypsum wet method, electron beam desulfurization, etc.), which after combustion of flue gas desulfurization is the world's main means of controlling SO2 pollution.
Limestone wet desulfurization system process: boiler low temperature economizer after the original smoke, into the absorption tower for desulfurization purification. Travertine Stone In the absorption tower in the original smoke and limestone slurry full contact with the reaction to remove the SO2, SO3, the formation of gypsum, the residual calcium sulfite in the bottom of the absorption tower in the bottom of the circulation of the fan is constantly bubbling air oxidation of the final formation of gypsum crystal. While the original flue gas temperature is further reduced to saturation temperature (about 50 ° C). After the desulfurization of the net flue gas by the demister, Travertine Stone the net flue through the chimney into the atmosphere.
Limestone characteristics on the performance of the absorption tower teach big, mainly reflected in the purity and activity of limestone. The activity of limestone can be expressed by the rate of dissolution. In the limestone particle size and dissolution conditions under the same conditions, Travertine Stone the dissolution rate is high activity. Limestone desorption rate is mainly related to limestone varieties. This is due to the formation of limestone and crystal structure caused by different. Limestone purity has a significant effect on desulfurization. Limestone in the Mg, Al and other impurities to improve the desulfurization efficiency although the beneficial side, Travertine Stone but more unfavorable is that when the absorption tower PH value dropped to 5.1, the fluoride in the flue gas and aluminum ionization synthesis of fluorine aluminum complex The coating covers the surface of the limestone particles. The presence of magnesium ions has a strong effect on the formation of the coating.
The encapsulation of this coating causes a decrease in limestone activity, which reduces the utilization of limestone. On the other hand, impurity magnesium carbonate, iron oxide, Travertine Stone alumina are acid soluble, they enter the absorption tower slurry system can produce soluble magnesium, iron, aluminum salts. Due to the circulation of the slurry, these salts will be enriched and a large amount of non-calcium ions in the slurry will weaken the dissolution and ionization of calcium carbonate in the dissolution system. Therefore, Travertine Stone limestone these impurities are high, will affect the desulfurization effect. Travertine Stone Due to the higher purity of limestone, the higher the purity of the limestone, so the use of high purity limestone do desulfurization agent will increase the operating costs, but this can be done by selling high-quality gypsum to make up for limestone wet flue gas desulfurization,Travertine Stone limestone purity at least 90 %the above. The smaller the particle size of the limestone, the greater the mass specific surface area. Since the dewaxing reaction of limestone is a solid-liquid two-phase reaction, the reaction rate is proportional to the specific surface area of the limestone particles. Therefore, Travertine Stone the limestone particle performance is high and the reaction rate is high, the desulfurization efficiency and the utilization rate of limestone are high, Limestone content is low, Travertine Stone is conducive to improving the quality of gypsum.