Reclaimed water from wastewater has become a prominent water source option to manage water scarcity. This study explores the potential of coconut husk biomass, a common waste material in Ghana, as a valuable low-cost resource for greywater treatment. Engineered column treatment was applied to investigate the influence of pyrolysis and biochar properties of coconut husk biomass waste on greywater treatment. Coconut husk biomass waste was pyrolyzed at 600°C and characterized using SEM, FTIR, and XRD. Three engineered columns with 1) raw coconut husk powder (RCHP), 2) charred coconut husk powder (CCHP), and 3) sand-gravel filters (control setup) were used. A hydrostatic head of greywater with a throughput of 8.0 ml/min and a hydraulic retention time of 45 min was maintained for engineered columns. The SEM image suggested an increased surface area and pores due to the pyrolysis of the husk biomass. RCHP and CCHP contributed to 63% and 95% turbidity removal, respectively. Experimental results showed high removal efficiencies of 71% COD for CCHP. The nitrate removal efficiency of 78.93%, 88.38%, and 28.65% was observed for RCHP, CCHP, and control respectively. The log removal of faecal coliform by CCHP was two orders of magnitude higher than RCHP. Faecal and total coliform removal was 2.87 log units for CCHP. Significant differences were observed between CCHP and RCHP, p < 0.05 for electrical conductivity and total dissolved solids of effluents. CCHP showed a promising potential for greywater treatment. Pyrolyzed coconut husk powder is a promising adsorbent applicable to greywater treatment.

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Chlorine is one of the many disinfectants used to ensure bacteriological safety of drinking water. Usually residual chlorine is maintained within the distribution network to combat any probable re-contamination of the distributed water. This residual free chlorine, however, decays in water due to its reaction with the bulk water and the pipe material or deposits on the pipe walls. This study aimed at determining and modelling chlorine decay in the Kumasi water distribution network (KWDN) and determined locations where residual chlorine boosting is necessary. A double-jacketed batch reactor and a constructed pilot distribution system (PDS) were used to determine the bulk and wall decay coefficients. The PDS was run using aged PVC pipes (15–20 years), asbestos concrete pipes (40–50 years) and cast iron pipes (84 years) that have been in use in the KWDN. The SynerGEE® hydraulic model was used to identify the ‘zero chlorine’ points and predict top-up quantities. The bulk decay coefficient was found to be 0.053 h−1 within 8 hours at 26 °C and the residual chlorine decayed within the bulk fluid by 32–34% of its initial dose. Under the conditions tested, the cast iron pipes had the highest overall decay coefficients (K). Five locations within the network were identified as probable chlorine boosting points).

This study successfully applied co-composting to municipal organic waste, faecal sludge and chicken manure feedstocks using optimized mixing ratios to yield high-end organic fertilizers. Nine (9) compost piles with different mixing ratios were prepared. Composting was monitored against physicochemical and nutritive parameters for 13 weeks. At curing, pH values and organic matter for piles were 5.5 to 9.0 and 15–45%, respectively. C/N ratio, nitrogen, phosphorus, and potassium levels of piles were satisfactory. Heavy metals Ni, Zn, Cu and Pb, met the EU standards except for Cd whose concentration was 12.9 to 73.2 mg/kg. Self-heating test results were comparable to the ambient temperature, and respiration tests showed values < 2 mg CO2•C/g organic carbon/day, indicating the cured compost is very stable. Although pathogens were present in the compost piles, the piles passed the phytotoxicity test with a minimum of 80.09%. Germination Index values were greater than 80% making the compost mature and phytotoxin-free. The variations between the cured compost piles were statistically significant, with a p-value < 0.05.