Optimization of Energy Consumption and Reduction of Environmental Emissions in Cookie Production using Data Envelopment Analysis and Genetic Algorithm Techniques

In this study, energy consumption and pollutant emissions in producing local cookies in Guilan province have been assessed. Optimization techniques in energy consumption to reduce pollutant emissions were also shown using two conventional data envelopment analysis (DEA) and multi-objective genetic algorithm (MOGA). Required data, gathered from 30 units preparing local cookies, were used as the preliminary data for energy and environmental analyses. Also, the environmental impacts in cookie production were investigated using life cycle assessment (LCA) approach. Inputs and output were converted to equivalent energies based on equivalent energy values. Results showed that 30533.66 MJ of energy would be needed to produce one ton of cookies. The share of natural gas in providing energy to produce one ton of cookies was calculated as high as 16945.2893 MJ. Based on LCA results, the global warming (GW) index was calculated as 3732.09 kg CO2 eq. per ton of local cookies.Based on the results of DEA models, the optimum amount of energy consumption is 30221.5856 MJ ton-1, the energy saving percentage is 1.02 %, and the reduction of GW index is 190.3739 kg CO2 eq. per ton of cookies produced in the units. Following patterns proposed by MOGA would results  21.62% reduction in energy consumption, main part of which associated with cookies in which walnuts are  used. Based on the optimization results of MOGA, GW index per production of one ton of cookie was calculated as 2923.74 kg CO2 eq.