Life cycle assessment of environmental impacts and energy demand for capacitive deionization technology

• Published in: Desalination 2016-12, Vol.399, p.53-60
• Main Authors: Yu, Ting-Hua, Shiu, Huan-Yu, Lee, Mengshan, Chiueh, Pei-Te, Hou, Chia-Hung
• Format: Article
• Language: English
• Subjects: Activated carbon electrode; Assessments; Brackish; Brackish water; Capacitive deionization; Deionization; Demand; Desalination; Electricity consumption; Environmental impact; Environmental performance; Life cycle assessment; Low energy demand; Ozone depletion
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2016.08.007

Assessment of life cycle environmental impacts and cumulative energy demand on a laboratory-scale capacitive deionizing (CDI) of brackish water was conducted in this study. The CDI system presented advantages of low energy demand at operation phase and low energy-related environmental impacts. With a measured electricity consumption for CDI operation at 1.44MJ (0.4kWh), the total cumulative energy demand for CDI system was estimated at approximately 23.9MJ for production of 1m3 of desalinated water. Results from the impact assessment indicated a global warming potential (GMP100) at 1.43kg CO2 eq, which was mainly attributed to the major reduction in electricity consumption as compared to conventional desalination technologies. Moreover, material utilization and chemical use were shown to be most responsible for overall environmental impacts in the CDI system, particularly for the use of N,N-dimethylacetamide (solvent) and titanium (material for current collector). Use of such chemicals might produce derivatives that contributed to major impacts in ozone depletion and acidification potentials. This suggests that additional efforts in future studies of CDI system may be made to substitute or reduce the two to enhance overall environmental performance of the system. [Display omitted] •Capacitive deionization is an environmentally friendly desalination technology.•Cumulative energy demand was the highest at operation phase.•Energy-related environmental impacts were lowest for electricity consumption.•Material and chemical uses contributed to most of the environmental impacts.•Decrease in use of Ti and DMAC is essential.