Variable speed drives as energy efficient strategy in pulp and paper industry

Abstract

The industrial sector is the largest consumer of energy in Malaysia, matched by the transport sector. Like many developing countries, the industrial sector contributes significantly to the national growth, and this economic growth drives the high growth in energy demand. Therefore, the increase in energy cost recently has created a situation where it has become essential to develop alternative energy technologies as well as improve efficiency. In this case, energy efficiency means reducing environmental degradation and increasing sustainability as well as cost savings. This thesis focuses on the economic benefits that can be obtained by replacing mechanical flow control of pumps and fans with variable speed drive in industrial sector in Malaysia. Firstly, the different topologies of variable speed drive i.e. the rectifier topologies as well as the control of invertors with Pulse Width Modulation is discussed. In this project, case studies taken from the energy audit data is also reported. These case studies explain the economic benefits of variable speed drive on pumps in the pulp and pump industries. Based on the load profile before and after the installations, energy savings up to 21% can be obtained