Advantages of boiler desulfurization dust collector technology

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Why is it necessary to remove dust and sulfur from boilers? With the development of industry, the air pollution caused by sulfur dioxide and its harmful effects have become increasingly significant environmental issues. Removing dust and sulfur is done for the purpose of environmental protection; it plays a crucial role in controlling air pollution and improving the ecological environment. Dust removal involves eliminating as much ash particles as possible from the flue gases emitted into the atmosphere, while sulfur removal aims to get rid of as much sulfur dioxide as possible from those flue gases. Dust removal and desulfurization cannot be delayed; today I will provide you with a detailed introduction to boiler desulfurization dust collectors. The boiler desulfurization dust collector employs a wet desulfurization and dust removal technology developed based on the mechanism of multiphase turbulent mass transfer. It combines centrifugal water film dust removal with spray boiling desulfurization and dust removal. The flue gas containing dust and harmful gases is accelerated through a venturi and a specially designed swirl chamber, where it collides with the atomized liquid sprayed in front of the venturi as well as the desulfurization liquid sprayed from the upper part of the tower, thereby generating a swirling force. The gas and liquid are mixed thoroughly due to this high-speed swirling motion before rising into the boiling reaction layer. The dust and harmful gases in the flue gas are captured and absorbed by the fine liquid particles in the desulfurization liquid. Since the atomized liquid particles create numerous interfaces, the efficiency of capturing and absorbing dust and harmful gases per unit volume of liquid is high. The purified flue gas is discharged into the atmosphere through a dehydrator, an exhaust fan, and a chimney. 　　The entire set of equipment for boiler desulfurization dust collectors is quite expensive, which is why buyers hope that suppliers possess excellent technical skills so that the equipment can last longer. The requirements for such dust collectors are quite high. Below are some of the technical requirements for desulfurization dust collectors (for reference only, not as definitive guidelines): 1. Through proper design, it is necessary to control key factors such as the pH level of the desulfurization absorbent solution, the flow rate of the flue gas, the misting condition of the absorbent solution, the residence time of the liquid droplets, and the appropriate liquid-to-gas ratio, in order to achieve an optimal absorption effect and ensure that the SO2 levels in the flue gas meet regulatory standards. The droplets entrained in the flue gas after desulfurization are collected, aggregated, and removed by the demister installed on the desulfurization absorption tower. 　　2. To meet the requirements for corrosion resistance and wear resistance, the components inside the tower can be made of SS316L material. The absorption tower is equipped with tower cleaning devices and combined mist removal systems, etc. The tower body is fitted with access manholes, operation platforms, and other auxiliary facilities. 　　The commonly used technology for desulfurization in boiler dust collectors is limestone-based desulfurization. Below are the characteristics and advantages of the limestone-gypsum desulfurization method: 　　Limestone-gypsum wet desulfurization has the following advantages: 　　(1) High desulfurization efficiency. The lime-gypsum wet flue gas desulfurization process achieves a desulfurization efficiency of over 99%; the flue gas after desulfurization not only has a very low sulfur dioxide concentration, but its dust content is also **reduced**. 　　(2) The technology is mature, offering good operational reliability. The operational efficiency of wet flue gas desulfurization systems using lime and gypsum abroad generally exceeds 98%. Thanks to their long history of development, mature technology, and extensive operational experience, the normal operation of these systems is not affected by the desulfurization equipment. In particular, the newly built desulfurization plants use the wet desulfurization process, which features a long service life and enables good investment returns. 　　(3) Absorbent resources are abundant and inexpensive. Limestone, which serves as the absorbent in the lime-gypsum wet flue gas desulfurization process, is widely distributed and abundant in China. In many areas, the quality of limestone is excellent, with a calcium carbonate content of over 90%, and in some cases even over 95%. As a result, the cost of producing lime remains low. Low operating costs. 　　(4) Desulfurization by-products are easy to utilize comprehensively. The desulfurization by-product of the lime-gypsum wet desulfurization process is desulfurized gypsum. In Japan and Germany, the annual production of desulfurized gypsum is around 2.5 million tons and 3.5 million tons respectively, and it is generally utilized in various ways; its main uses are in the production of building materials and as a retarder for cement. The comprehensive utilization of desulfurization by-products not only increases the profitability of the plant and reduces operating costs, but also lowers the expenses associated with the disposal of these by-products and extends the service life of the ash dump. 　　(5) Rapid technological progress. In recent years, extensive research and continuous improvements have been carried out abroad on the lime-gypsum wet process; for example, the absorption unit has been transformed from a combination of cooling, absorption, and oxidation towers into a single tower, the flow rate inside the tower has been significantly increased, and the performance of the nozzles has been further improved. Through technological progress and innovation, it is expected that issues such as the large land area required by this process can be gradually resolved. 　　The boiler dust collector protection system of the bypass system is an important measure to ensure the safety of the dust collector. It can issue an alarm in a timely manner through the control system. The common problems are as follows: 1. Abnormal flue gas temperature: A temperature detection device is installed on the inlet duct of the dust collector; by using this device to monitor the flue gas temperature, which is either below or above the set value, the PLC automatically activates the bypass system to prevent dew formation at low temperatures from causing blockages in the filter bags, or to prevent high-temperature flue gas from damaging the filter bags. 　　2. Boiler tube rupture: In the case of a small number of tube ruptures, a small amount of water has little impact on the large volume of hot flue gas, and the existing ash layer on the surface of the filter bags can cover it up; therefore, it does not have a significant effect on the bag filter. In the event of a large number of tube ruptures, resulting in significant changes in water volume and pressure as well as abrupt variations in the parameters of the boiler system, this will inevitably trigger a corresponding response from the system, which in turn sends signals to the dust removal system. The boiler will also take appropriate protective measures in accordance with its operating procedures: when the PLC controlling the dust remover receives signals indicating tube ruptures in the boiler, it controls the activation of the bypass system. Additionally, tube ruptures in the boiler cause an increase in flue gas temperature, and the temperature sensors installed in the main air inlet pipe will also trigger the activation of the bypass system. This dual layer of protection ensures the safety of the dust remover in case of boiler tube ruptures.