典型放射性固体废弃物燃烧过程的TG-FTIR-MS分析

TG-FTIR-MS ANALYSIS OF TYPICAL RADIOACTIVE SOLID WASTE COMBUSTION PROCESS

在“双碳”目标下,核能在发电领域面临着更多的发展机遇,但放射性固体废弃物的处置问题已成为核工业发展过程中一大阻碍。针对目前放射性固体废弃物的处置现状,采用热重-红外-质谱联用技术分析了典型放射性固体废弃物在燃烧过程中质量损失特性和气相产物的释放特性。结果表明:PE的燃烧过程只有1个阶段,且燃烧气相产物中除CO_(2)外还存在CO、烃类化合物、酮类或醛类等物质;与PE不同,阻燃剂的燃烧过程存在3个失重阶段:第1、2阶段燃烧释放的气体产物主要有H_(2)O、CO_(2)、HCl和烃类化合物等,第3阶段产生大量CO_(2),同时伴有HCl逸出;橡胶燃烧在3个阶段产生的气相产物有所区别,第1阶段的产物H_(2)O占大部分,CO_(2)仅占小部分,并释放烃类化合物、二甲基酮(或丙醛)、甲苯等物质;第2阶段的气体产物中CO_(2)含量大幅度提高;第3阶段的气相产物主要为CO_(2)。

Under the"two-carbon"goal,nuclear energy faces more development opportunities in the field of power generation,but the disposal of radioactive solid waste has become a major obstacle in the development of the nuclear industry.In view of the current status of radioactive solid waste disposal,this paper uses thermogravimetric-infrared-mass spectrometry technology to analyze the mass loss characteristics and gas phase product release characteristics of typical radioactive solid waste during the combustion process.The research results show that the combustion process of PE has only one stage,and in addition to CO_(2),there are substances such as CO,hydrocarbon compounds,ketones or aldehydes in the combustion gas phase products;different from PE,the combustion process of flame retardants has three weight loss stage,the gas products released by the combustion of the first and second stages are mainly H_(2)O,CO_(2),hydrogen chloride,hydrocarbon compounds,etc.The third stage produces a large amount of CO_(2),accompanied by the escape of HCl;the gas products produced by the rubber combustion in the three stages are different.The first stage product H_(2)O accounts for most of it,and CO_(2)only accounts for a small part,and releases hydrocarbons,dimethyl ketone(or propionaldehyde),toluene and other substances;the content of CO_(2)is greatly increased in the second stage;the gas phase product in the third is mainly CO_(2).