Pollution of water bodies is one of the areas of major concern to environmentalists. Water quality is an index of health and
well being of a society. Industrialization, urbanization and modern agriculture practices have direct impact on the water
resources. These factors influence the water resources quantitatively and qualitatively. The study area selected were the
Upper lake and Kolar reservoir of Bhopal, the state capital of Madhya Pradesh, India. The Upper lake and Kolar reservoir both
are the important sources of potable water supply for the Bhopal city. The physico–chemical parameters like temperature, pH,
turbidity, total hardness, alkalinity, BOD, COD, Chloride, nitrate and phosphate were studied to ascertain the drinking water
quality. 相似文献
An attempt has been made to establish an approach and a methodology to quantify electronic waste (e-waste) in India. The study
was limited to personal computers (PCs) and televisions (TVs) within the state boundaries of Delhi and in selected areas in
the National Capital Region (NCR). Material flow analysis was used to establish an e-waste trade value chain, where cathode
ray tubes (CRTs) were tracked in the e-waste dismantling stream of the CRT regunning process. The market supply method was
used to estimate the theoretical amount of e-waste for each item. Sensitivity analysis was carried out for PCs, using 5 years
and 7 years as the average life, and for TVs, using 10 years and 12 years as the average life. Externalities such as e-waste
entering the study area from outside were factored into the final e-waste analysis. Sensitivity analysis on the average life
also factored in elements of active usage, reuse, and storage of electronic items and consumer behavior into assumptions about
the obsolescence rate in market supply method. A primary survey indicated an output of 1800–2100 CRTs per day from all regunning
units in the study area. This range validated the theoretical output for an average life of 7 years for a PC and 12 years
for a TV. Using this approach, e-waste was estimated to reach 2 million units from the domestic market by 2010. 相似文献
Heavy metals in higher concentrations are often encountered in domestic sewage of developing and under-developed countries. High metallic concentrations can stress reactor sludge biomass morphology impeding its performance in organics reduction. However, the extent of damage and ability of sludge biomass to recover from the metallic stress is not fully understood. Also, there is no protocol to identify and prevent the sludge biomass from metallic stress in fully functional sewage treatment plants (STPs). This study investigates performance, metabolic activity, morphology, and settling characteristics of the sludge biomass under different Co(II) stress conditions. The extent of recovery in biomass, when the supply of Co(II) metal ion was discontinued in the inlet stream, was explored. The study also proposed a protocol based on simple settling characteristics of sludge biomass to get an early indication of metal infiltration to prevent potential damage to the biomass morphology. Four sequencing batch reactors (SBRs) with Co(II) ion concentrations of 0 (designated as RCo0), 5 (RCo5), 25 (RCo25), and 75 mg/L (RCo75) in the feed were operated with a cycle time of 12 h. Reactors were operated for 35 days with Co(II) in the feed (termed as stressed phase operation) followed by 24 days of operation without Co(II) in the feed (termed as recovery phase operation). Results show that COD removal in reactor RCo75 reduced to 48% on the 10th day of stressed phase operation, showing a lag in COD removal due to metallic stress. The activity of biomass in reactors RCo5, RCo25, and RCo75 was reduced by 39%, 45%, and 49%, respectively, in the stressed phase compared to the biomass in control reactor. Recovery in COD removal efficiency and specific biomass activity were observed in all the reactors after the removal of metallic stress. The settleability of sludge biomass in reactors RCo25 and RCo75 was significantly affected. Transformation in the shape of flocs in reactor RCo25 and RCo75 biomasses revealed the prolonged effect of metallic stress, which was observed to be irreversible even during the recovery phase operation.