Low-temperature desulfurization, with sulfuric acid as a by-product

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The technical principle of the new catalytic method involves loading catalytic components onto an activated carbon carrier to produce a catalyst. SO2, H2O, and O2 in the flue gas are adsorbed in the pores of the catalyst, and under the catalysis of the active components they turn into active molecules that rapidly react to form H2SO4. The generated sulfuric acid becomes concentrated in the carrier; once it reaches saturation, it is regenerated (by flushing with clean water from the top of the desulfurization tower), thereby releasing the active sites of the catalyst and restoring its desulfurization capacity. Compared with the traditional carbon method, the catalytic method requires less energy for desulfurization, results in less catalyst consumption, and eliminates the need to install a separate sulfuric acid production facility; it also features a shorter process flow and more stable and reliable operation. The desulfurization mechanism is as follows: file:///C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ksohtml3160\wps1.png O2 → 2O*. file:///C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ksohtml3160\wps2.png SO2 + O* → SO3*. file:///C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ksohtml3160\wps3.png H2O + SO3* → H2SO4*. The core of the new catalytic flue gas desulfurization technology lies in the catalyst; the **Flue Gas Desulfurization Center at Sichuan University possesses independent intellectual property rights for the production of desulfurizing agents. Unlike traditional desulfurization active coke and activated carbon, this catalyst is prepared by using carbon materials as a carrier onto which certain active components are loaded; it exhibits catalytic activity in the process of oxidizing SO2 to produce acid. The desulfurization process is actually a sulfuric acid production process. The new catalyst has a long service life; no continuous addition is required, and only minor replenishments are needed each year for maintenance. Technical features: New type catalyst – Traditional vanadium-based catalysts have a ignition temperature of around 4000°C, are suitable for SO2 concentrations above 5%, and are prone to poisoning. The new catalyst can react at 500°C, is suitable for SO2 concentrations below 3%, and has strong resistance to poisoning. Coupling technology: The traditional processes are catalytic conversion and absorption, which are carried out in two steps within two separate devices. The new catalytic process is a catalytic absorption coupling technology, with the two-step reaction taking place within a single device. High efficiency: High desulfurization efficiency. The desulfurization efficiency is greater than 95%; especially when dealing with flue gases at low concentrations, it can overcome the limitations of the gas-liquid equilibrium in absorption-based technologies, ensuring that the desulfurization efficiency does not decline. In practical applications, desulfurization efficiencies of up to 100% have even been achieved. High adaptability and wide range of application: It can handle various operating conditions featuring complex flue gas composition, sulfur dioxide concentrations ranging from 0.001% to 3%, and flue gas temperatures between 60 and 200°C. Removes sulfuric acid mist: It can effectively eliminate sulfuric acid mist, meeting the specific emission limit of 5 mg/m3 for sulfuric acid mist set by current industry standards; it is recommended by the China Sulfuric Acid Industry Association for use. Simple: short production process, few devices, and small footprint ； It’s easy to operate. In daily operation, only the regeneration pump runs intermittently; generally, one person is sufficient per shift for such a unit, or the operator of another production unit can also handle its operation, thereby saving on labor costs. Environmental protection: Stable, safe, and reliable operation. Since it is a dry-process technology, there are no issues such as scaling and clogging that occur with wet-process technologies ； No secondary pollution. The by-product sulfuric acid is returned to the sulfuric acid plant or other units for use, so there are no other effluents or solid pollutants. Economy: No desulfurizer required. The greatest advantage of catalytic technology is that the catalyst accelerates the reaction process without being consumed itself; in contrast to absorption technology, which requires continuous addition of desulfurization agents, the catalysts used in this new catalytic technologyほとんど need no additional additives and only require repeated regeneration, resulting in low operating costs.