摘要
【目的】为了明确废催化剂再生废水排放和回用的有害金属离子含量指标,提出废水循环利用解决方案,本文对某燃煤电厂废脱硝催化剂再生过程中产生的超声废水和酸洗废水进行了研究。【方法】首先连续清洗废催化剂模块,对产生的超声废水和酸洗废水进行成分检测并分析废水的特点;其次采用浸渍方法模拟毒化新脱硝催化剂,研究废水中金属离子的累积规律和有害金属离子在催化剂表面的吸附规律,对毒化后催化剂表面吸附的金属离子含量与催化剂脱硝效率之间的对应关系进行研究。【结果】研究表明,连续清洗时,当清洗到25个催化剂模块后,清洗液中各金属离子含量在固液界面上达到吸附-溶解平衡;清洗到80个催化剂模块时,清洗液的清洗效果明显变差,废液会对化学中毒程度小的催化剂造成污染;废液中Fe离子浓度大于1.0%以上时,催化剂的脱硝效率降低到50%左右,几乎不再发生变化;溶液中Cr离子浓度从1.0%增加到3.0%时,催化剂的脱硝效率逐渐增加后趋于稳定。【结论】因此,再生废水中Fe、Cr元素对催化剂脱硝效率的影响几乎可以忽略不计。当K、Na、Ca、Pb、Hg、As浓度分别达到0.700%、0.500%~0.600%、0.100%、0.045%、0.400%~0.500%和0.020%时,需要及时对超声废水与酸洗废水进行脱盐或其他处理,以保证催化剂再生清洗活化效果。
[Objective]To elucidate the indicators of harmful metal ions in wastewater discharge and reuse,and to provide superior solutions for the recycling of wastewater from the regeneration of waste catalysts,this paper systematically studied the ultrasonic wastewater and acid washing wastewater generated during the regeneration process of waste denitration catalysts at a coal-fired power plant.[Methods]By continuously washing the waste catalyst module,the main characteristics and component features of the ultrasonic and acid washing wastewater produced during the regeneration process of waste catalysts were identified.[Results]After cleaning 25 catalyst modules,the concentrations of various metal ions in the cleaning solution reach adsorption-dissolution equilibrium at the solid-liquid interface.Cleaning efficacy noticeably decreases after cleaning over 80 catalyst modules,also contaminating catalysts with minor chemical poisoning.The impregnation method was employed to simulate the poisoning of new denitration catalysts,and the study explored the accumulation patterns of metal ions in wastewater and the adsorption rules of harmful metal ions on the surface of the catalyst,investigating the correlation between the content of metal ions adsorbed on the surface of the poisoned catalyst and the denitrification efficiency of the catalyst.In the solution,when the Fe ion concentration exceeds 1.0%,the catalyst's denitrification efficiency decreases to around 50%and remains almost unchanged.When the Cr ion concentration in the solution increases from 1.0%to 3.0%,the catalyst's denitrification efficiency gradually increases and then stabilizes.[Conclusion]Therefore,the impact of Fe and Cr elements in the regenerated wastewater on the catalyst's denitrification efficiency is almost negligible.When the concentrations of K,Na,Ca,Pb,Hg,and As respectively reach 0.700%,0.500%-0.600%,0.100%,0.045%,0.400%-0.500%and 0.020%,it becomes necessary to promptly desalinate or treat ultrasonic and acid-washing wastewater to ensure effective regeneration and activation of the catalysts.
作者
杨建辉
李含
程茜
周梅
赵建新
徐光辉
俞润炜
YANG Jianhui;LI Han;CHENG Xi;ZHOU Mei;ZHAO Jianxin;XU Guanghui;YU Runwei(China Energy Longyuan Environmental Protection Co.,Ltd.,Beijing 100039,China;China Energy Longyuan Catalyst Jiangsu Co.,Ltd.,Yixing 214200,Jiangsu China;China Energy Wuxi Environmental Protection Technology Co.,Ltd.,Wuxi 214000,Jiangsu China)
出处
《电力科技与环保》
2025年第3期413-425,共13页
Electric Power Technology and Environmental Protection
基金
国家能源集团科技创新项目(GJNY-20-197-2)
关键词
燃煤电厂
废脱硝催化剂
再生废水
中毒元素
循环利用
coal-fired power plants
waste denitration catalyst
regenerated wastewater
poisoning element
recycling
