Study of ammonium chloride formation phenomena in the waste pyrolysis process
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
This paper describes a technological study of a Japanese Pyrolysis Plant for Waste Treatment. Sometimes in the earlier stage of the plant operation, a certain amount of solid material deposition was observed.
The result from chemical analysis showed that the major component of this material was ammonium chloride. Ammonium chloride was deposited on the pipe walls. The deposited ammonium chloride forms a dense brick like material that prohibits the gas movement. The gas in the pipe is choked by this deposition and this is disrupting the continuously plant operation. The source of the ammonia chloride was supposed to be Hydrochloric vapours and ammonia vapours, which gasified from the waste and formed somewhere in the plant.
Although effective mechanical way to prevent the ammonia chloride accumulation was developed and continuously operation of the plant was established successfully, essential reduction of ammonium chloride formation was sought for future applications. To reach a conclusion with this issue several Test and Simulations were made, to find out effective countermeasures. The Paper is describing the result from five different simulations in the program ChemSage to predict what is happening with ammonia at different parameters. It also describes the results from several Tests performed on a laboratory scaled cracker, to verify how ammonia behaved under certain conditions. This paper concludes that the major part of the ammonia is formed in the cracker or/and downstream of the cracker.
What could be done about the formation are as follows: Increase the temperature in the cracker. Have longer residence time in the cracker. Insert more oxygen into the cracker. Rather a combination of all these three solutions at the same time is the best way to come to an ending with the ammonium chloride issue without having to change the performance of the whole process too much.
Place, publisher, year, edition, pages
2001. , 120 p.
, TRITA-KET-IM, ISSN 1402-7615 ; 2001:12
Social Sciences Interdisciplinary
IdentifiersURN: urn:nbn:se:kth:diva-32461OAI: oai:DiVA.org:kth-32461DiVA: diva2:410737
Subject / course
Degree of Master - Environmental Engineering and Sustainable Infrastructure
www.ima.kth.se NR 201408042016-03-162011-04-142016-03-16Bibliographically approved