To assess the applicability and economical efficiency of V 2 O5/TiO2 catalyst in a marine low-speed electronic-injection diesel engine selective catalytic reduction (SCR) system, a D-1000-5 electric vibration table and a Cummins ISDe4-SCR performance test bench were used to test the activity and vibration resistance of homemade A , B, C group of V2 O5/TiO2 catalyst sample .Catalyst B was selected as the SCR target catalyst for marine medium-speed diesel engine . D2 and E3 cyclic tests were performed for the target catalyst B in the test bench of 6CS21/32 large-power marine diesel engine.Bench test results show that the economical efficiency of the homemade V 2 O5/TiO2 catalyst is slightly higher than that of the imported catalyst .At a medium-high exhaust temperature , the denitration rate can reach 90%;at a low exhaust temperature , the activities vary .When the exhaust temperature is higher than 250℃, the denitration rate of cat-alyst B is more than 80%.The properties of the SCR system for a marine low-speed diesel engine can be further re-searched.The activity and mechanical strength of catalyst C meet the SCR requirements of a marine medium-speed diesel engine.When the temperature is lower than 250℃, the conversion efficiency decreases quickly .However, due to low cost , the system is quite competitive in the market of marine medium-speed diesel engines .The temperature scope of catalyst A is narrow and is applicable only for the engine with an exhaust temperature above 330℃.Catalyst packaging can improve the vibration resistance of the catalyst .%为评定V2O5/TiO2催化剂在船舶低速电喷柴油机SCR(selective catalytic reduction)系统的适用性与经济性,本文基于D-1000-5电动振动台和康明斯ISDe4-SCR性能试验台架,分别对国内生产的A、B、C三组V2O5/TiO2催化剂小样进行活性和抗振性实验,最终选定催化剂B为船用中速机SCR目标催化剂,并在6CS21/32大功率船用中速机试验台上对目标催化剂B进行D2、E3循环测试.台架测试结果表明:国产V2O5/TiO2催化剂的经济性较进口催化剂略有提高,中高排气温度下脱硝率可达90%、较低排气温度下活性各有差异;排气温度高于250℃时,催化剂B的脱硝率稳定在80%以上,可进一步研究其船用低速机SCR系统的特性;催化剂C的活性和机械强度满足船用中速机SCR要求,温度低于250℃时,转化效率急剧降低,但其价格低,具有较强的船用中速机市场竞争力;催化剂A温度窗较窄,仅适用于排气温度高于330℃的发动机上;催化剂封装可提高催化剂抗振动冲击能力.
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