UTILISATION OF RAINWATER AS SUSTAINABLE WATER SUPPLY FOR TOILET FLUSHING AT INSTITUT TANAH DAN UKUR NEGARA (INSTUN)
This is one of consultations projects by NAHRIM to develop a rainwater harvesting system (RWHS) at multi-storey Block B hostel building for INSTUN. The aim of RWHS development at INSTUN is to reduce dependency on treated water supply from Lembaga Air Perak (LAP) for toilet flushing. Initially, INSTUN required to develop RWHS at Block A and Block B hostel buildings, however due to limited allocation, RWHS for Block B is chosen to be as pioneer project. It is one of the efforts to saving annual water bills from utilizing treated water for toilet flushing. A revised Tangki NAHRIM is used to analyze the reliability and optimum size of rainwater collection tank for the purpose of putting the idea into a complete engineering design. Through site investigation, the RWHS is designed to occupy for 127 water closets in each hostel rooms. It is estimated that each room daily need is 1,944 liters with assumption of flushing three times a day. In addition, a scenario with estimated monthly total average 144 occupants need about 13.5 liters/day for toilet flushing. It was estimated that 434m2 roof catchment is capable to collect about 78,526.33m3 of rainwater for toilet flushing. A 20m3 of rainwater collection tank is designed and integrated with main components such as gutter, downpipes, filters, analog meters, variable speed drives pumping system, conveyance pipes and storage tanks. A booster pump is included to deliver collected rainwater into toilets for 127 hostel rooms. This scenario is utilized for RWHS engineering design to achieve optimum efficiency and favorable reliability by INSTUN. A one-year observation indicates that RWHS at INSTUN has achieved 81% efficiency and 61% reliability to cater flushing demand.
Authors
Abstract
This is one of consultations projects by NAHRIM to develop a rainwater harvesting system (RWHS) at multi-storey Block B hostel building for INSTUN. The aim of RWHS development at INSTUN is to reduce dependency on treated water supply from Lembaga Air Perak (LAP) for toilet flushing. Initially, INSTUN required to develop RWHS at Block A and Block B hostel buildings, however due to limited allocation, RWHS for Block B is chosen to be as pioneer project. It is one of the efforts to saving annual water bills from utilizing treated water for toilet flushing. A revised Tangki NAHRIM is used to analyze the reliability and optimum size of rainwater collection tank for the purpose of putting the idea into a complete engineering design. Through site investigation, the RWHS is designed to occupy for 127 water closets in each hostel rooms. It is estimated that each room daily need is 1,944 liters with assumption of flushing three times a day. In addition, a scenario with estimated monthly total average 144 occupants need about 13.5 liters/day for toilet flushing. It was estimated that 434m2 roof catchment is capable to collect about 78,526.33m3 of rainwater for toilet flushing. A 20m3 of rainwater collection tank is designed and integrated with main components such as gutter, downpipes, filters, analog meters, variable speed drives pumping system, conveyance pipes and storage tanks. A booster pump is included to deliver collected rainwater into toilets for 127 hostel rooms. This scenario is utilized for RWHS engineering design to achieve optimum efficiency and favorable reliability by INSTUN. A one-year observation indicates that RWHS at INSTUN has achieved 81% efficiency and 61% reliability to cater flushing demand.
Citation
Elyasabath Mohd Ghazali. 2020. UTILISATION OF RAINWATER AS SUSTAINABLE WATER SUPPLY FOR TOILET FLUSHING AT INSTITUT TANAH DAN UKUR NEGARA (INSTUN). Digital NAHRIM Publication Repository.