CAM-Y Baking Soda Grinding Machine

Air Classifier Grinding Machine-Leading Flue Gas Deacidification Process Sodium Bicarbonate Grinding

Hazardous waste treatment, steel plant coke oven, thermal power generation, municipal waste, sludge incineration, non-metallic ore burning, ceramic industry, glass manufacturing

With the increasingly stringent requirements of environmental protection laws and regulations, Perlman's process based on the principle of dry deacidification of baking soda developed in combination with advanced processes in Europe and the United States has been applied more and more. The dry method using sodium bicarbonate as the adsorbent adsorbs and removes various pollutants contained in the flue gas. Its purification effect can be compared with other known methods, such as the spray adsorption method using lime milk as the adsorbent. Dry flue gas purification can be used not only in coal power plants, hazardous waste treatment, municipal waste or alternative fuel incineration plants, but also in industrial furnaces in glass, cement, metallurgy and other industries. Dry flue gas purification can economically remove gases containing acidic substances, such as SO2, HCI, etc., and meet the national standard for flue gas emission.

The flue gas contains a lot of acidic gas. After a lot of data and experiments, only sodium bicarbonate (baking soda, NaHCO3) can react with the acidic components in the flue gas to a certain degree. It removes acidic pollutants in the flue gas through chemical adsorption, and it can also remove some inorganic and organic trace substances through physical adsorption. This process sprays fine sodium bicarbonate powder directly into the high-temperature flue gas. At high temperatures, sodium bicarbonate decomposes to produce sodium carbonate Na2CO3, H2O and CO2.

Generally, the flue gas temperature is between 140 and 250 °C. Due to the high activity of the sodium bicarbonate adsorbent, a slight excess of sodium bicarbonate (stoichiometric factor between 1.1 and 1.3) is usually sufficient.

The particle requirements are related to the components in the flue gas, and the required particle size for the removal of SO2 and HCl will be different. Due to transportation and storage reasons, sodium bicarbonate raw materials are usually coarse particles (d50 value of about 200 microns). To achieve higher reactivity, the adsorbent must have a larger specific surface area. Therefore, the sodium bicarbonate must be ground to a certain degree of fineness before being injected into the flue gas pipe. For example, the fineness of sodium bicarbonate must reach d90 <20 µm to remove SO2. The removal of HCl only requires d90 <35 µm. If the system is operated correctly, it can remove more than 95% of SO2; the removal rate of HCl can even reach 99%. In order to maintain the required fineness of sodium bicarbonate during long-term operation, after grinding with an air grinder, the adsorbent is transported by gas transportation and directly passed into the flue gas pipe through multiple nozzles to ensure that it is evenly dispersed in the pipe. . The design of this equipment is simple and durable. Compared with other flue gas purification methods, its investment and operating costs are lower.

Sodium bicarbonate grinding process will be the core process of this technology
CAM-Y Baking Soda Grinding Machine

The problem of equipment fouling in negative pressure air grinding systems is often the focus of discussion. The cleaning of the equipment, especially the cleaning of the conveying fan, is too time-consuming. In addition, the fouling on the fan impeller may also peel off during the startup and shutdown process, resulting in the vibration of the fan and the oscillation of its operating state. Therefore, it can be considered to change from a negative pressure process to a positive pressure process. In the new working mode, the fan is installed before the classifying mill, and the process air is forced into the grinding system. The advantage of this working mode is that the ground sodium bicarbonate is not transported through the fan, which completely avoids the problem of fan fouling. In addition, the power consumption of the fan has also been reduced, resulting in lower operating costs, but a higher test has been put on the sealing performance of the equipment. The design structure, processing accuracy and coordination of the equipment have strict requirements, and the cost of the equipment is also Will be higher.

The dry adsorption process has made a breakthrough in the removal of gaseous inorganic pollutants. This process has become one of the standard processes for removing hydrogen chloride, hydrogen fluoride and sulfur oxides, and is especially suitable for on-line purification of flue gas in incineration plants.

Through the latest development of process and equipment technology, the performance of dry flue gas purification process is completely comparable to that of high-efficiency wet process. The applicability and economy of the dry flue gas purification process using sodium bicarbonate requires a separate analysis for each case.

The Pallman CAM series sodium bicarbonate grinding system is flexibly customized, and the simple and durable equipment greatly improves the availability of the process and the reliability of the flue gas purification process.