Impact of Low-Pressure UV Lamp on Swimming Pool Water Quality and Operating Costs

Electro-oxidation and UV irradiation coupled method for in-site removing pollutants from human body fluids in swimming pool

A comprehensive study was conducted to investigate how ultraviolet (UV) irradiation combined with electrochemistry (EC) can efficiently remove human body fluids (HBFs) related pollutants, such as urea/creatinine/hippuric acid, from swimming pool water (SPW). In comparison with the chlorination, UV, EC, and UV/chlorine treatments, the EC/UV treatment exhibited the highest removal rates for these typical pollutants (TPs) from HBFs in synthetic SPW. Specifically, increasing the operating current of the EC/UV process from 20 to 60 mA, as well as NaCl content from 0.5 to 3.0 g/L, improved urea and creatinine degradation while having no influence on hippuric acid. In contrast, EC/UV process was resilient to changes in water parameters (pH, HCO3-, and actual water matrix). Urea removal was primarily attributable to reactive chlorine species (RCS), whereas creatinine and hippuric acid removal were primarily related to hydroxyl radical, UV photolysis, and RCS. In addition, the EC/UV procedure can lessen the propensity for creatinine and hippuric acid to generate disinfection by-products. We can therefore draw the conclusion that the EC/UV process is a green and efficient in-situ technology for removing HBFs related TPs from SPW with the benefits of needless chlorine-based chemical additive, easy operation, continuous disinfection efficiency, and fewer byproducts production.

Residential swimming pools maintenance under an environmental perspective

Swimming pools provides various benefits for users, but their owners need to carry out constant maintenance to ensure water quality and user safety. This paper goal was to assess the maintenance process of residential swimming pools, through Life Cycle Assessment based on NBR ISO 14040:2014 and NBR 14044:2014. The standard steps were followed and primary data on materials and quantities for the treatments were collected during 2022. The purchase costs of the treatment process were obtained, which based the cost analysis. The Impact Assessment Method used was the ReCiPe Endpoint (H) 2016, which assesses damage across three categories. The water, electricity and hypochlorite production processes were the most impactful in the categories of damage to human health, ecosystems and resources availability. These inputs production have an intense natural resources consumption and causes emissions into the environment. The highest expenses in pool maintenance were associated to human resources (worker) and chlorine purchase, followed by electricity. Scenarios were created to identify feasible changes to reduce the impacts. The waiver of water for replacement in the rainy season had greater potential for reducing impacts than the consumption changes in electricity and chlorine.

Advances and research needs for disinfection byproducts control strategies in swimming pools

The control of disinfection byproducts (DBPs) in swimming pools is of great significance due to the non-negligible toxicity and widespread existence of DBPs. However, the management of DBPs remains challenging as the removal and regulation of DBPs is a multifactorial phenomenon in pools. This study summarized recent studies on the removal and regulation of DBPs, and further proposed some research needs. Specifically, the removal of DBPs was divided into the direct removal of the generated DBPs and the indirect removal by inhibiting DBP formation. Inhibiting DBP formation seems to be the more effective and economically practical strategy, which can be achieved mainly by reducing precursors, improving disinfection technology, and optimizing water quality parameters. Alternative disinfection technologies to chlorine disinfection have attracted increasing attention, while their applicability in pools requires further investigation. The regulation of DBPs was discussed in terms of improving the standards on DBPs and their preccursors. The development of online monitoring technology for DBPs is essential for implementing the standard. Overall, this study makes a significant contribution to the control of DBPs in pool water by updating the latest research advances and providing detailed perspectives.

Influence of the Use of an Additional Oxidant (Chlorine Dioxide) in Water Treatment on Swimming Pool Water Quality

This article presents the results of experiments on the effect of chlorine dioxide, applied as an additional oxidant, on swimming pool water quality. Three doses of chlorine dioxide were applied: 22, 44 and 66 mg/m3. At each research stage, prior to the actual experiment, in which the oxidant was dosed, the background was tested, i.e., water samples were taken from a conventional treatment system (without chlorine dioxide). The experiments showed that chlorine dioxide effectively removes organic compounds and their chlorine derivatives. For the highest dose of ClO2, CODMn decreased by almost 88% and chloroform concentration by 75%. Chlorine dioxide also effectively supports water disinfection. At the highest dose, the number of mesophilic bacteria decreased by 60% and the number of psychrophiles by 94%. However, after the dosing of this oxidant had been discontinued, a deterioration of the microbiological water quality and the secondary growth of microorganisms were observed. Chlorine dioxide also caused an increase in conductivity and the concentration of inorganic compounds (nitrates, total chlorates and chlorites). The effect of this agent on the combined chlorine concentration was not observed. The reported experiments have shown that this measure is not unequivocally beneficial in terms of improving swimming pool water quality.