1 AIT Asian Institute of Technology

Formulation of a pollution index for carpet industries in Kathmandu valley

AuthorSharma, Suman Prasad
Call NumberAIT Thesis no. EV-95-36
Subject(s)Pollution--Nepal--Kathmandu valley
NoteA thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering.
PublisherAsian Institute of Technology
Series StatementThesis ; no. EV-95-36
AbstractWoolen carpet manufacturing is a major industrial act1v1ty in Nepal. Carpet export constituted more than 65 percent of the total national exports in terms of convertible currency income amounting to more than an equivalent of 113 Million US Dollars in the fiscal year 1990/91. Carpet manufacturing activities are mostly concentrated inside Kathmandu valley and more than 140 units of carpet washing and wool dyeing plants presently operate causing adverse impacts on the surface and ground water resources of the valley. This study investigates the extent of these effects and presents an aggregated view of environmental experts in Kathmandu towards the carpet manufacturing sector through the formulation of a pollution index for the carpet industries. It is estimated that more than 500 Liters of water is consumed in manufacturing one m2 of carpet, out of which, the carpet washing activity alone consumes approximately 400 Liters per m2 of output. The carpet industry is the second highest consumer of ground water, following the public water supply, and extracts around 5,000 m3/day of ground water from the acquifiers in Kathmandu . Wool scouring activity is presently carried out openly in rivers imparting more than 12,000 mg/Liter of BOD to the local rivers and streams. Wool dyeing plants discharge effluents that are colored and of elevated temperatures ( 85 °C). Traces of heavy metals like Chromium was also found in dyeing effluents with concentrations up to 4.7 mg/Liter. Carpet Washing effl uents are laden with detergents and create problems due to their amphoteric nature. The composite effluent from one carpet washing plant, studied during this research, resulted in a pH value of around 2. A pollution index, prepared on the basis of linguistic ratings provided by 45 environmental experts in Kathmandu, assigns the value of 0.39 to the carpet industry sector on a scale of 0 to 1. Fuzzy analysis has been used for accounting the uncertainties involved in the linguistic ratings. It has been observed that trainings of safe chemical handling and good house keeping practices are necessary, for plant supervisors especially those from the carpet washing plants. A switch to alternative washing processes with process water recycling needs to be considered. Partially centralized treatment plants for treatment of dye effluents is one of the solutions to allow the dyeing industry function in a more environmentally friendly manner. Open wool scouring in rivers must be discouraged. Zoning for carpet industries location needs to be implemented as a long term solution.
Year1995
Corresponding Series Added EntryAsian Institute of Technology. Thesis ; no. EV-95-36
TypeThesis
SchoolSchool of Environment, Resources, and Development (SERD)
DepartmentDepartment of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC))
Academic Program/FoSEnvironmental Engineering and Management (EV)
Chairperson(s)Reutergardh, Lars Bertil
Examination Committee(s)Stoll, Uwe;Thapa, Gopal Bahadur;Kiran Kumar Bhattarai
Scholarship Donor(s)World Health Organization;Swedish International Development Authority (Sida)
DegreeThesis (M. Eng.) - Asian Institute of Technology, 1995


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