An Innovative Approach for Carbon Capture Sequestration on a Thermal Power Plant through Conversion to Multi-Purpose Fuels- A Feasibility Study in Indian Context

摘要

Government of India has declared its policy on Carbon Dioxide (CO2) abatement by the announcement and adoption of the 'National Action Plan on Climate Change'. It has also made voluntary commitment at the UNFCCCs Paris Summit that the country shall decrease its Carbon Intensity by 30-33% by 2030. The path chosen makes it imperative that the CO2 which forms 95% of the GHG emissions be reduced. Out of total annual emission of about 1700 Million Tons per annum (MTPA), CO2 emitted by the Coal based thermal power plants of capacity over 180GW amounts to about 860 MTPA. For EPA regulations to be implemented there have to be a road map as to how this can be done without major impact on the cost or efficiency of power generation. The thermal plants in India have a thermal efficiency of about 35% and an emission ratio of 0.90 kg/kWh of CO2 emissions as published by Central Electricity Authority (CEA). The reduction of 33% intensity as promised by India at COP-21: Paris; would translate to a decrease of CO2 emissions to a level of 0.58 kg/kWh by 2030. This decrease is possible by a combination of abatement and recycling measures like augmentation of Low Carbon Technologies (LCT) such as Renewable and Clean Coal Technologies (CCT) and Carbon Capture & Sequestration (CCS) on our Fossil Fuel based thermal power plants. However, as regards post combustion CCS plants on coal fired units, the CO2 capture by an amine system of 30% CO2 capture would mean an energy penalty of about 25% including a minimum of 10% for compression and pumping to deep reserves like mineral rocks, gas hydrates and ocean. In any case, the energy penalty in Indian context, when CO2 sequestration is considered a far more appropriate option than CO2 storage the energy penalty still remains at level of 15%. This can be further reduced to a level of 4-5% if solar thermal device is used for production of steam for an amine solvent regeneration and stripping of CO2. The same can be demonstrated only after establishment of pilot plant of CO2 Capture and Sequestration plant integrated with Concentrated Solar Power (CSP) for carrying out system optimization studies, having variable fluid dynamic configuration. The paper covers description and test results of Post Combustion Carbon Capture & Sequestration Pilot Plant installed at the Rajiv Gandhi Proudyogiki Vishwavidyalya (RGPV), Bhopal in Central India, for CO2 capture and conversion into fuel molecules like H2 and CH4 from associated Oil fired Boiler and a Biomass gasifier. A feasibility study of installation of CCS on a 500MW unit together with integration of solar concentrator for steam generation for reducing energy penalty in regeneration is also presented.