非金属衬里材料在烟气脱硫装置上的应用

催化裂化再生装置中产生的烟气是炼油企业污染物的主要来源。根据国家环保标准的要求,炼厂必须采用烟气脱硫装置(FGD)来控制二氧化硫的排放。烟气脱硫装置所处腐蚀环境极为恶劣,若不采取有效的防护措施,将影响整个系统的安全稳定运行。烟气脱硫装置如果整体采用耐蚀合金材料,价格昂贵。介绍了适用于烟气脱硫装置的几种非金属衬里及其性能和应用区域,包括橡胶衬里、玻璃鳞片树脂衬里、耐蚀胶泥、耐蚀砖板衬里、整体玻璃钢等常用非金属衬里,以及聚脲、纳米复合涂料等新型高性能防腐蚀涂料等。橡胶衬里的耐化学腐蚀性和抗介质渗透性较好,但耐温性差,一般用于机械负荷大而内部环境温度较低的区域,如吸收塔内部、浆液系统和烟道。玻璃鳞片树脂衬里的综合性能较好,被广泛应用于烟道、吸收塔等烟气脱硫装置的各个区域。玻璃钢衬里多用于脱硫系统中的输送管道和吸收塔内喷淋管道等部位。胶泥和耐蚀砖板衬里是应用较早的防腐蚀技术,其抗冲击性能差。聚脲和纳米复合涂料是重防腐蚀涂料,是FGD装置腐蚀防护的新技术,虽然在炼厂脱硫装置中有一些应用,但其使用效果还有待证明。

Application of Non-metallic Linings in Flue Gas Desulfurization Plant

Flue gas generated by the catalytic cracking regenerator is the main pollution source from oil refining enterprises. According to national environmental protection standards, flue gas desulfurization (FGD) plant must be used to control emissions of sulfur dioxide. FGD plant is in an extremely corrosive environment. Without effective protection measures, it will affect the safe and stable operation of the whole system. Because the corrosion-resistant alloy material for overall use in FGD is expensive, the nonmetallic material for linings is an important alternative. The article introduced several nonmetal linings in FGD device and their properties and application, including common nonmetal lining (rubber lining, glass resin flake lining, corrosion-resistant cement, corrosion-resistant brick lining, and whole fiberglass reinforced plastic) and novel high-performance anti-corrosion coatings ( polyurea and nanometer composite coatings, etc. ). Rubber lining has good chemical corrosion resistance and anti-permeability against media, but its temperature resistance is poor, so rubber lining is generally used in the region of large mechanical load and at low temperatures, such as internal part of absorption tower, slurry system and low-temperature flue. Glass flake resin lining has favorably comprehensive performance, which is widely applied in various areas of the flue gas desulfurization device, such as the flue, the absorption tower and so on. FRP lining is often used in pipeline of the desulfurization system and spray pipe in the absorption tower and other sites. Corrosion-resistant cement and brick lining are the earlier applied anti-corrosion technologies with poorer impact resistance compared with other non-metallic linings. Polyurea and nanometer composite coating are heavy-duty coatings and new technologies for protection of FGD equipment from corrosion. Even though they have some applications in the refinery desulfurization device, their performance remains to be proved.