Chemical coagulation is commonly used in raw water and wastewater treatment plants for the destabilisation of pollutants so that they can be removed in the subsequent separation processes. The most commonly used coagulation chemicals are aluminium and iron metal salts. Electrocoagulation technology has also been proposed for the treatment of raw waters and wastewaters. With this technology, met...

Electrocoagulation (EC) is electrochemical water and wastewater treatment technology which in its simplest form uses an electrochemical cell where a dc voltage is applied to the electrodes, usually made of Iron or Aluminum, and the electrolyte is the water or wastewater. Current theory of EC has not been able to explain all the phenomena associated with the process, among others the differences...

A laboratory investigation provided preliminary comparison of trace element contaminant water treatment capabilities for four iron-based filter materials. The iron-based filter materials tested were zero-valent iron (ZVI), porous iron composite (PIC), sulfur modified iron (SMI), and iron oxide/hydroxide (IOH). Two types of trace element contaminant solutions were tested, one combined As, Cr, an...

Soluble Fe(II) in ground water in Denmark is mostly removed conventionally by the simple process known as purely physico-chemical (or abiotic). By this process, the raw water is exposed to atmospheric oxygen to oxidise the iron from soluble Fe(II) to insoluble Fe(III) oxides, which is then removed by single or double filtration units, depending on the ground water quality. Ground water containi...

A laboratory study to optimize a low cost technology for small scale drinking water treatment in rural Bangladesh Harmen van der Laan Abstract High concentrations of arsenic in drinking water form a major threat for public health in more than 70 countries worldwide. The situation is Bangladesh is seen as the worst incidence of arsenic poisoning: it is believed that 30 million people in Banglade...

Mine drainage waters vary considerably in the range and concentration of heavy metals they contain. Besides iron, manganese is frequently present at elevated concentrations in waters draining both coal and metal mines. Passive treatment systems (aerobic wetlands and compost bioreactors) are designed to remove iron by biologically induced oxidation/precipitation. Manganese, however, is problemat...

Arsenic is a carcinogenic metalloid that is currently regulated in drinking water. The levels of arsenic in finished water in an existing water treatment plant are exceeding the current regulation of 10 μg/L. One of the available technologies for arsenic removal from groundwater is adsorption onto coagulated flocs and in this field, ferric chloride is the most commonly used coagulant for arseni...

Iron in groundwater is one of the problems that render the water unsuitable for drinking. The concentration above 0.3 mg/L is common in groundwater. The conventional method of removal is by precipitation under oxic condition. In this study, iron removal under anaerobic conditions was examined by batch experiment as a main purpose. The process involved by purging of groundwater samples with H2S ...