Author(s)

W. Wirojanagud & P. Veerayutsil

Abstract

Recovery of chromium of tanning wastewater by precipitation with saline groundwater and acidification W. Wirojanagud & P. Veerayutsil National Research Center for Environmental and Hazardous Waste Management and the Department of Environmental Engineering, Faculty of Engineering, Khon Kaen University. Abstract Recovery of chromium-contaminated wastewater generated from the tanning factory could be made by treating the wastewater with metal hydroxide prepared from saline groundwater. Calcium, magnesium and sodium are the main components of saline ground water that can be precipitated as metal hydroxide when reacted with alkaline. The saline ground water sample used in this study contained a salinity of 1,000-1,500 mg/l C1, pH of 6.8-7.4, calcium of 3,900-7,500 mgll and magnesium of 2,100-2,500 mgll. When the pH of this saline ground water was raised to 13.2-13.5 with sodium hydroxide, the white slurry of calcium hydroxide concentration of 28,00&87,000 mgll and magnesium hydroxide concentrati

Keywords