Assessment of the physiochemical properties and sustainability of locally produced ceramic G-filter in a long term experiment

In India, Ceramic Water Filters (CWF) named G-filters are becoming a point-of-use household water treatment solution. The filter's reliability may be primarily characterized by the filtrate turbidity and microbial removal efficiency. The temperature and moisture gradients of the location affect its performance. This paper describes a 19-week laboratory investigation of G-filters simulating field conditions. The basic objective during the study was to ascertain the effective useable life of the filter. The discharge rate and turbidity reduction ability of the filters are studied in depth. The G-filters were prepared using locally available salty clay and sawdust taken in equal volume fractions. A total of 30 filters with a 9-liter capacity each were used for the experiments. The results showed that CWFs can reduce turbidity effectively. The influent water used for the study had a mean turbidity of 7.65 NTU, which reduced in the range of 0.03 NTU to 1.03 NTU. Over the course of four months, the average flow rate decreased from 1.94 Lh-1 to 0.93 Lh-1. Although a soft brushing of filters improved the filtration rate but that too failed in the long run. Brunauer–Emmett–Teller (BET) nitrogen adsorption–desorption measurements were used to determine the variation in pore size of filters with time. An average pore radius of 2.91 nm was found in the original filter that has not been used for filtration experiments. Moreover, an average pore radius of 1.77 nm, 1.21 nm, and 1.22 nm were reported in G-filters through which 427.5 L, 807.5 L, and 1035.5 L, respectively, of water were passed. This reduction in pore size is attributed to the clogging of pores over a period of time. This study aims to collect performance data to establish a scientific model using statistical analysis for implementing CWF technology in developing nations.