Environmental Performance of Process Changes in Efficient Use of Water Resource

摘要

Water is used in many processes as a process material as well as a cleaning medium. Use of water is associated with several environmental impacts and therefore methods and practices to use water efficiently and minimize water consumptions to reduce environmental burdens are encouraged in cleaner production applications. Although cleaner production opportunities are applied to improve environmental performance,methods are needed to determine whether those opportunities actually contribute to a reduction in the adverse environmental impacts.This paper presents a method to evaluate the environmental friendliness of a production process based on environmental impacts due to the use of water resource.It can be used to determine the process alternative which has the 'best' usage of the water resource based on environmental performance.The environmental impacts looked at are the water resource depletion due to the use of water as a process material and the environmental impact due to the wastewater generated. Depending on the amount and strength of wastewater released, the impacts on the terrestrial and aquatic environment and the obnoxious odour impact are analyzed.This method is applied and tested on the paddy soaking operation of paddy parboiling process. The hot soaking method is analyzed with a process modification to use less amount of water for the soaking operation. The process with the modification has shown no effect on the quality of the rice due to the change in the process. Although the process modification has lead to low water consumption, higher strength wastewater has been produced which has resulted in increased environmental burden.