气态膜分离技术对含氨废气的回收

Recovery of ammonia-containing waste gas by gas membrane separation technology

超纯氨气是电子工业中的重要电子气体,LED外延片在生产过程中,整个MOCVD反应过程在富N的环境下进行,每台MOCVD一天要用超纯氨气约40kg。氨气在MOCVD炉中只有约0.03%的N随反应氨气进入外延片中生成N层;约29.97%的氨气分解成氮气和氢气,最终以气态形式排入大气;约70%的氨气未发生反应。大量的气态氨通过管道排出,造成原材料的浪费。氨气是一种无色、有刺激性恶臭味的气体,它在常温下为气态,极易溶于水,氨作为国家法规限值排放污染物,具有毒性和腐蚀性,易对生态环境造成污染,因此MOCVD排放的废氨气处理已经成为LED芯片生产厂家迫切需要解决的问题。某光电公司为了防止废气排放对周围环境造成污染,决定利用气态膜分离技术对排放的含氨废气进行回收成一定的氨水,并产生一定的经济效益,达到变废为宝的目的。

Ultrapure ammonia is an important electronic gas in the electronics industry.During the production process of LED epitaxial wafers,the entire MOCVD reaction process is performed in a N-rich environment.Each MOCVD uses about 40 kg of ultrapure ammonia gas per day.Only about 0.03%of ammonia in the MOCVD furnace will enter the epitaxial wafer with the reaction ammonia to form an N layer;about 29.97%of the ammonia will be decomposed into nitrogen and hydrogen,and finally will be discharged into the atmosphere as gaseous;about 70%of ammonia No reaction occurred.A large amount of gaseous ammonia is discharged through the pipeline,causing waste of raw materials.Ammonia is a colorless,irritating,malodorous gas.It is gaseous at room temperature and easily soluble in water.Ammonia emits pollutants as a national regulatory limit,which is toxic and corrosive,and is easy for the ecological environment.As a result of pollution,the disposal of waste ammonia by MOCVD has become an urgent problem for LED chip manufacturers.In order to prevent exhaust emissions from causing pollution to the surrounding environment,an optoelectronic company decided to use the gas membrane separation technology to recover the ammonia-containing waste gas discharged into a certain amount of ammonia,and generate certain economic benefits,thus turning waste into treasure.