Bio-syngas as fuel in the steel industry's heating furnaces: a case study on feasibility and CO2 mitigation effects
2011 (English)Conference paper (Other academic)
Today, climate change is at the top of the political agenda. The European Commission has set atarget to reduce greenhouse gas emissions by 20 % by 2020, compared to 1990 levels. The steelindustry contributes significantly to industrial CO2 emissions, and thus it is important for thissector to find options to reduce its CO2 emissions. One alternative is to substitute fossil fuelswith biomass derived fuels; a promising option is to replace LPG (Liquefied Petroleum Gas) used asfuel in heating furnaces with bio-syngas produced through the gasification of biomass. This paperis a feasibility study of the implementation of this concept at a Swedish scrap-based steel plant.The results have been obtained through a case study approach with interviews and literaturesurveys. The study shows that if a fuel gas mixture of 50 vol% bio-syngas and 50 vol% LPG would beused, the global CO2 emissions would be reduced by 5,400 tonnes/year. Moreover, a full-scale fuelsubstitution would result in reduced emissions by 68,600 tonnes/year. In the case of a partial fuelsubstitution, a 4 MWth High Temperature Agent Gasifier (HTAG) is a suitable choice while a 45 MWthindirectly heated Circulating Fluidised Bed Gasifier (CFBG) would be suitable for a full-scale fuelsubstitution. In the case of a fuel switch, the lower heating value of syngas, compared to LPG, notonly implies that a different combustion technology must be used, but also that the exhaust gasflows will be substantially larger, and consequently the exhaust gas cleaning system must bedesigned with dimensions suitable for larger flows. Excess heat from the gasifier can be used forspace heating, but if the excess heat replaces district heating from a Combined Heat and Power(CHP) plant, the global CO2 emissionsreductions would be less than if the excess heat is not recovered.
Place, publisher, year, edition, pages
2011. 3842-3853 p.
Fuel conversion, steel industry, biomass, case study, gasification
IdentifiersURN: urn:nbn:se:liu:diva-71824OAI: oai:DiVA.org:liu-71824DiVA: diva2:454231
ECOS 2011 - 24th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, July 4-7, Novi Sad, Serbia