Industrial decarbonization is crucial to keeping the global mean temperature<1.5°C above pre-industrial levels.Although unabated coal use needs to be phased out,coal is still expected to remain an important so...Industrial decarbonization is crucial to keeping the global mean temperature<1.5°C above pre-industrial levels.Although unabated coal use needs to be phased out,coal is still expected to remain an important source of energy in power and energy-intensive industries until the 2030s.Decades of coal exploration,mining and processing have resulted in~30 billion tonnes of waste-coal tailings being stored in coal impoundments,posing environmental risks.This study presents an environmental life-cycle assessment of a coal-processing technology to produce coal pellets from the waste coal stored in impoundments.It has been shown that the waste-coal pellets would result in the cradle-to-gate global warming of 1.68-3.50 kgCO_(2,eq)/G_(Jch),depending on the source of electricity used to drive the process.In contrast,the corresponding figure for the supply of conventional coal in the US was estimated to be 12.76 kgCO_(2,eq)/G_(Jch).Such a reduction in the global-warming impact confirms that waste-coal pellets can be a viable source of energy that will reduce the environmental impact of the power and energy-intensive industries in the short term.A considered case study showed that complete substitution of conventional coal with the waste-coal pellets in a steelmaking plant would reduce the greenhouse-gas emissions from 2649.80 to 2439.50 kgCO_(2,eq)/t_(steel).This,in turn,would reduce the life-cycle greenhouse-gas emissions of wind-turbine manufacturing by≤8.6%.Overall,this study reveals that the use of waste-coal pellets can bring a meaningful reduction in industrial greenhouse-gas emissions,even before these processes are fully decarbonized.展开更多
文摘Industrial decarbonization is crucial to keeping the global mean temperature<1.5°C above pre-industrial levels.Although unabated coal use needs to be phased out,coal is still expected to remain an important source of energy in power and energy-intensive industries until the 2030s.Decades of coal exploration,mining and processing have resulted in~30 billion tonnes of waste-coal tailings being stored in coal impoundments,posing environmental risks.This study presents an environmental life-cycle assessment of a coal-processing technology to produce coal pellets from the waste coal stored in impoundments.It has been shown that the waste-coal pellets would result in the cradle-to-gate global warming of 1.68-3.50 kgCO_(2,eq)/G_(Jch),depending on the source of electricity used to drive the process.In contrast,the corresponding figure for the supply of conventional coal in the US was estimated to be 12.76 kgCO_(2,eq)/G_(Jch).Such a reduction in the global-warming impact confirms that waste-coal pellets can be a viable source of energy that will reduce the environmental impact of the power and energy-intensive industries in the short term.A considered case study showed that complete substitution of conventional coal with the waste-coal pellets in a steelmaking plant would reduce the greenhouse-gas emissions from 2649.80 to 2439.50 kgCO_(2,eq)/t_(steel).This,in turn,would reduce the life-cycle greenhouse-gas emissions of wind-turbine manufacturing by≤8.6%.Overall,this study reveals that the use of waste-coal pellets can bring a meaningful reduction in industrial greenhouse-gas emissions,even before these processes are fully decarbonized.
