Change search
ReferencesLink to record
Permanent link

Direct link
High Temperature Air/Steam Gasification (HTAG) Of Biomass – Influence of Air/Steam flow rate in a Continuous Updraft Gasifier
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
2013 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Biomass is an important source of energy and the most important fuel worldwide after coal, oil and natural gas. Biomass does not add carbon dioxide to the atmosphere as it absorbs the same amount of carbon in growing as it releases when consumed as a fuel. Its advantage is that it can be used to generate electricity with the same equipment or power plants that are now burning fossil fuels. However, the low energy density of the biomass requires developments and advances in conversion technologies in order to increase process efficiency and reduce pollution. One of the most promising converting methods for treatment of biomass and waste feedstock is gasification. In this study a highly preheated air/steam of temperatures >800oC is introduced to the gasifier which is fed with wood pellets’ feeding rate 40-50 kg/h.

The system is redesigned to work as a continuous type updraft HTAG. The aim of the studies was to test the performance of an Updraft configuration in various operating conditions using Biomass (wood pellets) as the feedstock, and facing primarily technological difficulties and process limitations. Determining the Temperature distribution along the reactor and synthesis gas composition of the process are reported for various operating parameters.

During the experiment it is observed that the introduction of more steam flow rate increases the LHV (lower heating value) of the synthesis gases. Three case studies (Case1, Case2, and Case3) are conducted, each case having different biomass feeding rate, steam flow rate and process air flow rate. The result show that the amount of LHV of gas varied from 3 to 4.2 MJ/Nm3, the H2: CO ratio is between 0.5-0.9 and the CO/CO2 ratio has range 1.0-1.7.  Case 3, in which 40 kg/h biomass feeding rate and 80 kg/h Steam flow rate is maintained gives High LHV, high H2/CO ratio and more CO/CO2 ratio among the rest case studies.

Further improvement can be done within the reactor, increase in retention time and variation of more parameters can examine, in order to get the optimum result in future.

Place, publisher, year, edition, pages
National Category
Other Materials Engineering
URN: urn:nbn:se:kth:diva-119835OAI: diva2:612653
Subject / course
Energy Technology
Educational program
Master of Science - Materials Science and Engineering
Available from: 2013-03-25 Created: 2013-03-23 Last updated: 2013-03-25Bibliographically approved

Open Access in DiVA

master thesis report_mjalilarif(1655 kB)1125 downloads
File information
File name FULLTEXT01.pdfFile size 1655 kBChecksum SHA-512
Type fulltextMimetype application/pdf

By organisation
Materials Science and Engineering
Other Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 1125 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 253 hits
ReferencesLink to record
Permanent link

Direct link