JOINT OPTIMIZATION OF MAINTENANCE AND PRODUCTION PLANNING WITH CARBON EMISSION CONSIDERATIONS

With increasing the value of optimized production plan and cost of equipment as well as raising the degree of difficulty to change spare parts and equipment, the importance of maintenance planning has doubled. Therefore, we can conclude that nowadays, the necessity of integrating production and maintenance planning is realized for the entire industrial owner and it is going to be the main concern of industrial owners to find the ways which help them optimize their costs. This study presented a new methodology to optimize the production and maintenance planning simultaneously. In terms of the environment, the carbon emission policy was applied. Therefore, the manufacturer should adhere to the emission limitations, which are placed on a company that emits carbon into the environment; otherwise, they should pay penalty. To control the cost of penalty, two types of production strategy including green and regular strategies were applied. In green strategy, the material and fuel were recyclable. Thus, it did less damage to environment but it was more expensive than the regular one. This essay seeks to optimize the amount of production of each strategies by balancing the amount of production with each kind of strategy and we should optimize the cost of production. To formulate the mathematical model, we consider costs of Preventive Maintenances (PMs) and mean of Corrective Maintenance (CM) as objective values to determine the production rate and number of PMs. By using MATLAB program, we could solve the model for two types of algorithm including Genetic and VDO algorithm and compare the solution together. Overall, it was concluded that in small-sized problems, VDO can answer more quickly than GA; yet, they were the same in terms of the solution quality. For some problems, VDO had the best solution, while GA could give the best solution to some other problems. However, overall, their function was somehow equal.