Energy and Cost Analysis in Pulp and Paper Industry by Auditing Techniques: A Case Study

摘要

Men's quest for comfort and luxury has increased the demand for energy. So, the energy conservation has become essential to overcome the mounting problems of energy crisis. Efficient energy management, conservation of resources, carbon capture should be considered to solve out energy and environmental issues. In last 25 years, the world energy demand has increased by 70% and still increasing at a higher rate annually. Reduction of energy consumption and environmental issues can be achieved through adoption of environment friendly technologies such as massive plantation, rain water harvesting, use of treated effluent for irrigation and by auditing technologies etc. In the present case study of a pulp and paper industry, the energy auditing for Pumps, Barometric leg of washers, Agitator, Coal fired boilers, Dryer head of steam cylinder has been carried out using energy Level-I (The Walk Through) and Level-II (Standard) auditing techniques. It has been observed in case of pumps, that 50% energy and cost can be saved by replacing the 60 HP pumps with high efficiency 30 HP pumps for the same workload. In case of washers if >10 m barometric leg is provided then there is no need for the vacuum pumps (2×60 HP), installed for washers. So the total cost and energy consumption over these two pumps can be reduced. Interlocking system for agitators was suggested to avoid continuous running of agitators during paper machine shut down period, and thereby saving 41.7% energy. TDS blow down valve in place of manual valve can prevent 0.5% blow down losses in case of coal fired boilers. By insulating the dryer head of steam cylinders the estimated energy saving potential is 3.5% and investment cost for insulating (app. Rs. 2.0 lakh), can be paid back in 5-6 months.