Environmental Control Technology for Atmospheric Carbon Dioxide

Abstract

The impact of fossil fuel use in the United States on worldwide CO2 emissions and the impact of increased coal utilization on CO2 emission rates are assessed. The aspects of CO2 control are discussed as well as the available CO2 control points (CO2 removal sites).The primary factor affecting the practicability of a CO2 control system is the energy required by the control system. Removal of CO2 from the atmosphere or from the ocean surface water is energetically not feasible with a fossil energy source. More CO2 is generated than is recovered. Removal from the stacks of fossil fuel power plants requires the least amount of energy and allows use of a fossil energy source. Estimates of the energy required to capture and recover CO2 from coal-fired power plant stacks by various processes are presented. The effect on the reduction in overall plant efficiency is determined.Although capture and recovery of CO2 are important considerations in the overall scheme of CO2 control, disposal or reuse of recovered CO2 is the greatest problem in the CO2 control chain. Of the several options considered, deep ocean storage appears to be a possibility.Two control scenarios are evaluated, one based on the absorption of CO2 contained in power plant flue gas by seawater; the other, based on absorption of CO2 by MEA. Captured CO2 is injected into the deep ocean in both cases. The analyses indicate that capture and disposal by seawater is energetically not feasible, whereas capture and disposal using MEA is a possibility. However, the economic penalties of CO2 control are significant. At a CO2 removal efficiency of 50% the power generation efficiency of a conventional coal fired plant would be reduced from 34% to 25% and the cost is expected between 15% 6% and the power generation cost would increase by a factor of from 4 to 7.The use of non-fossil energy sources, such as hydroelectric, nuclear or solar energy is considered as an alternative for limiting and controlling CO2 emissions resulting from fossil energy usage.KeywordsDeep OceanFossil Energy SourceFossil Fuel Power PlantPower Plant EfficiencyPower Generation CostThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.