Udara S. P. R. Arachchige

Waste Heat Utilization for CO2 Capture in the Cement Industry

The focus of this work is utilization of waste heat in a cement kiln flue gas in an amine-based CO2 absorption process. The high temperature flue gas from the cement kiln is used to generate steam in a waste heat boiler. The steam is then used to replace some of the steam required in the stripping section of the CO2 capture plant. The required surface area for heat exchange, the cost of installing this area and the payback time of the installation is calculated. The flue gas capture model was developed using the Aspen Plus simulation software. The available excess heat in the cement manufacturing process is calculated to 18 MW for the base case considered. The heat transfer area is calculated as 3115m. The total cost of the heat exchanger was

Simulation of Carbon Dioxide Capture for Aluminium Production Process

3.9 million, and the payback time is about 1 year, demonstrating the economic feasibility of applying heat integration when implementing an amine-based CO2 capture process in a cement kiln system.

Role of solar flat plate collectors in reducing green house gases in Nepal

A carbon capture process model was developed for the flue gas from aluminium production process. There are four different cases, which were considered for the simulation studies in Aspen Plus process simulation tool. Several CO2 concentrations, 3, 4, 7 and 10 vol%, in the flue gas from the aluminium production is investigated. The required re-generation energy in the stripper section is in the range of 3.0 3.5 MJ/kg CO2 for 85% removal efficiency and 3.2 3.5MJ/kg CO2 for 90% removal efficiency and 3.4 3.6MJ/kg CO2 for 95% removal efficiency. It can be clearly seen that, (58-65)%, (67-75)%, (61-67)% and (52-60)% of energy requirement of case I, II, III and IV (3%, 4%, 7% and 10% of CO2 in the flue gas) can be replaced by available heat for replacing the re-generation process. According to the present study, it can be stated that, 4% CO2 content in the flue gas is given the optimum available heat to replace the maximum amount of energy requirement in re-generation process.

New Model Configuration for Post Combustion Carbon Capture

Questionnaire survey performed to know the pattern of energy consumption for cooking, water heating and animal feeding in the outskirts of Kathmandu Valley. The site selected for the questionnaire survey was Ghimire Gaun, Biruwa, Dadhikot, village development committee of Bhaktapur district. After the data collection from a questionnaire survey, the total amount of energy consumed for cooking and water heating purpose in the village was calculated. The greenhouse gases emission from each energy sources was calculated by the linear relation between the intensity of activity and the emission resulting from the activity. The annual consumption of firewood in Ghimire Gaun was found to be about 23.5 tonne (97,905 kWh), of which about 3.18 tonne (13,235.04 kWh) is used for water heating purpose. The annual liquefied petroleum gas consumption is 1.69 tonne (23,105.48 kWh). The total amount of CO2 reduction by one solar flat plate is around 195 kg/year. The re-boiler energy requirement for CO2 capture process model is around 4MJ/kg CO2. Therefore, total amount of energy required to capture the CO2 is around 195*4MJ/year (780 MJ/year). Therefore, by installing one flat place, it can be saved 780MJ/year of energy instead of capturing CO2 from gasification.

Viscosities of Pure and Aqueous Solutions of Monoethanolamine (MEA), Diethanolamine (DEA) and N-Methyldiethanolamine (MDEA)

—This paper discusses about possible configurations to improve the process with reduction of re-boiler energy demand. The simulations are performed in the Aspen Plus process simulation tool to check the required re-boiler duty. In the new model configuration, the rich solvent to the stripper is split using splitter block and supplied to the stripper section. The re-boiler duty for 85%, 90% and 95% removal efficiency cases are calculated for new model configuration and it is 3255, 3360 and 3614 kJ/kg CO 2 respectively. This is around 10% reduction of re-boiler duty compare to the conventional process.