Environmental issues in Nepal and solving them using the cleaner production approach
Owing to rapid industrialisation, environmental problems in sectors such as water, air, waste, energy and forestry in Nepal are reaching a crisis point. Although the Nepalese government has been trying to solve these problems by various means, the main emphasis has been on end-of-pipe solutions. This paper investigates why Nepal needs to implement Cleaner Production concepts as a matter of urgency and provides several recommendations to the government as well as sectors such as waste, industry, energy and pesticide regarding the implementation of such concepts.
Performance Evaluation of Central Wastewater Treatment Plant: a Case Study of Hetauda Industrial District, Nepal
A central wastewater treatment plant (CWWTP) was established in Hetauda Industrial District (HID) to treat industrial as well as sanitary wastewater. Brewery, dairy, vegetable ghee and soap factories are major sources of high strength wastewater in HID. The main objective of this study was to evaluate the performance of CWWTP in terms of BOD5, COD, TSS, TDS, oil and grease and ammonical nitrogen removal. Moreover, the performance of the CWWTP related to pretreatment of wastewater in those industries, so performances of pretreatment were also included in this study. Samples of wastewater were collected from the CWWTP and from brewery, dairy, and soap factories for characteristic analysis. The secondary data of influent and effluent monitoring of the CWWTP and pretreated wastewater of vegetable ghee factory was also used. This study revealed that average concentrations of BOD5, COD, TSS, TDS, oil and grease, and ammonical nitrogen in the effluent of CWWTP were 252, 1,226, 595, 384, 6.2 and 36.16 mg/l, respectively, which did not meet the effluent standards for BOD5, COD and TSS. The pretreatment of wastewater at brewery, dairy, vegetable ghee and soap factories were not sufficient to meet the pretreatment criteria. To overcome inefficient treatment, more factory sewerage systems should be connected to the CWWTP to solve the problem of under BOD loading in anaerobic pond.wastewater should be treated to meet pretreatment criteria before discharging to the CWWTP.
Metal pollution of River Msimbazi, Tanzania
Abstract The Msimbazi River in Dar es Salaam is polluted with industrial, urban and agricultural waste waters. A preliminary investigation on the extent of metal pollution (Hg, Cr, Cu, Zn, Fe, Ni, Cd, Mn, Al) was made from samples of sediments and biological indicators. The metal concentrations were in general low, but some of our results indicated industrial pollution.