Arsenic Contamination In Groundwater In Bangladesh: An Environmental And Social Disaster
Before 1971 (Year of independence from Pakisthan), thousand of people died each year due to water born diseases in Bangladesh. To provide safe water, with help of UNECEF, the Government of Bangladesh (GoB) installed millions of tubewell which ensured safe drinking water to 97% population of Bangladesh. When the people are habituated with tubewell water, then in 1993, the people of Bangladesh discover the silent killer, the Arsenic. It becomes a challenge to an excellent public health success story. This paper has reviewed environmental and social implication of Arsenic in Bangladesh
ADDIS ABABA: Sanitation Status
Sanitation provision in Addis Ababa (the capital of Ethiopia) is grossly deficient, as in most cities in sub-Saharan Africa: most people do not have access to a hygienic toilet; large amounts of faecal waste are discharged to the environment without adequate treatment; this is likely to have major impacts on infectious disease burden and quality of life (Hutton et al. 2007). This article briefly summarizes the current sanitation situation in Addis Ababa.
Activated Sludge Process
Activated sludge (AS) is a process dealing with the treatment of sewage and industrial wastewaters and developed around 1912-1914. There is a large varity of design, however, in principle all AS consist of three main components: an aeration tank, which serves as bio reactor; a settling tank ("final clarifier") for seperation of AS solids and treated waste water; a return activated sludge (RAS) equipment to transfer settled AS from the clarifier to the influent of the aeration tank.