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Assessment of energy and exergy efficiencies of a grate clinker cooling system through the optimization of its operational parameters

Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
Energy (Impact Factor: 4.84). 10/2012; 46(1):664-674. DOI: 10.1016/j.energy.2012.06.074

ABSTRACT

Grate coolers are widely used in cement industries to recover heat from hot clinker, coming out from the rotary kiln. This study focuses on improving the energy, exergy and recovery efficiencies of a grate cooling system through the optimization of its operational parameters such as masses of cooling air and clinker, cooling air temperature, and grate speed. It has been found that the energy and recovery energy efficiencies of a cooling system can be increased by 1.1% and 1.9%, respectively, with every 5% mass increases of cooling air. Similarly, it has been estimated that energy and recovery energy efficiencies can be increased by 2.0% and 0.4% with every 5% increase of cooling temperature. The exergy and its recovery efficiencies found to be increased by 3.6% and 2.2%, respectively, for the same condition. Energy efficiency and energy recovery efficiencies are increased by 3.5% and 1.4% with every 9.1% increase of grate speed. Using heat recovery from the exhaust air, energy and exergy recovery efficiencies of the cooling system found to be increased by 21.5% and 9.4%, respectively. It has been found that about 38.10% and 30.86% energy cost can be saved by changing mass flow rate of clinker and mass flow rate of cooling air, respectively.

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Available from: Jamal Uddin Ahamed
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    • "Also Ahamed et al. (2012) focused on improving the energy, exergy and recovery efficiencies of a grate cooling system through the optimization of its operational parameters such as masses of cooling air and clinker, cooling air temperature , and grate speed. They used the energy and exergy analyses to determine how the operational parameters of the grate clinker cooling system and the recovery of heat from the hot exhaust air, affect the efficiencies [18]. Sanaei et al. (2012) performed the exergy and energy analyses to assess the use of quality of energy in Iran's industrial sector. "
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    • "Waste heat utilization in process industries have been investigated based on engineering practice. Ahamed et al. [12] examined how the operating parameters of the grate clinker cooling system and heat recovery from the cooling air, influence the first and second law efficiencies. Karellas et al. [13] energetically and exergetically studied two different waste heat recovery methods: a water-steam Rankine cycle, and an Organic Rankine Cycle. "
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    • "The results showed when an optimised design is adopted, the expected savings could range 10 % to 25 % of total cost. Ahamed et al. (2012) focused on improvement of the energy, exergy and recovery efficiencies of a grate cooling system through the optimisation of its operational parameters such as masses of cooling air and clinker, cooling air temperature, and grate speed. Nakano (2011) developed a differential equation that described sintering cost from basic relationships between relevant operational variables/parameters and to discuss the cost-minimum state and the direction for cost-minimum operation by applying the equation. "
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