Application of the Swimming Pool Backwash Water Recovery System with the Use of Filter Tubes

Molecules. 2021 Oct 31;26(21):6620. doi: 10.3390/molecules26216620.

Abstract

During the operation of swimming pools, large losses of water from the backwash of swimming pool filters are observed. This water is often discharged into sewers or used to sprinkle sports grounds. The aim of the research was to design and build an installation for purification and recovery of backwash water (BWW). It consists of flocculation, pre-filtration, and ultrafiltration based on filter tubes and ozone disinfection. Backwash water treatment installation contributes to purification and improvement of water quality. The effectiveness of the removal of microbial contamination with the use of the system was over 99%. The high efficiency of removing physicochemical impurities was also achieved. Water turbidity was reduced from 96.9 NTU to 0.13 NTU. After using the system, the oxidability of water decreased from 6.26 mg O2∙dm-3 to 0.4 mg O2∙dm-3. When using the system, a reduction of total organic carbon by 80% was also noticed. After the treatment process, water meets the strict criteria and can be returned to the pool system of water as fresh water with parameters of supply water-directly to the overflow tank. It has been shown that up to 96% of water can be recovered with the technology. The cost comparison showed annual savings of over EUR 9000.

Keywords: backwash water; management of backwash water; swimming pool; ultrafiltration.