Municipal Drinking Water Treatment
Municipal Drinking Water Treatment: Access to safe drinking water is considered to be a basic human right. However, more than one-sixth of the world’s population, predominantly in developing countries, lack reliable access to such water. Customers complain to drinking water companies regarding incidents like taste, odour, colour, slime, low pressure and no supply of water. In the UK, it is estimated that one-third of all customer complaints concerning drinking water are related to water discolouration (Cook et al., 2005). These complaints greatly undermine customers’ confidence in water companies.
Iron and Manganese contamination of water have long been considered to only lead to aesthetic problems, in that they are secondary contaminants that have little or no adverse health effects. However, research conducted by Wasserman et al. (2006) indicated a relationship between increased Mn concentrations in drinking water and reduced intellectual functions of children. Increased levels of Iron and Manganese concentrations have been found to be the main cause of drinking water discolouration (Slaats, 2002). Furthermore, discoloured water could also lead to coloured stains on laundries and sinks, increased treatment costs, reduced treatment capacity and increased pumping costs. Water with high concentrations of Iron and Manganese has been found to give water an unpleasant metallic taste and vegetables cooked with it become dark and look unappetizing (Herman, 1996).
High Iron and Manganese levels can lead to non-compliance with drinking water regulations. The drinking water standard for most jurisdictions for iron is 0.3 milligrams per liter (mg/l), and the standard for manganese is 0.05 mg/l respectively. The quality of water changes as it travels from source to consumers in Water Distribution Networks (‘WDNs’). Although water companies generally set post-treatment targets of Fe and Mn to about 3% of their respective MCLs, low concentrations of Fe and Mn still enter the network and gradually accumulate on pipe walls within WDNs. Given the wrong conditions, such as high flows created by a water main burst or high diurnal consumption of drinking water, these accumulated particles may subsequently lead to water discolouration and end up in customers’ taps.
Municipal water treatment is vital for providing safe, clean, and palatable drinking water to communities. As urban populations continue to grow, the demand for effective water treatment methods that can efficiently address various contaminants increases. KT-20 filter media has gained recognition as a versatile solution in municipal water treatment, effectively removing a wide range of contaminants, including iron, manganese, hydrogen sulfide (H₂S), turbidity, organic compounds, suspended solids, odor, and color. This essay explores the mechanisms of KT-20, its application in municipal water systems, and its efficacy in meeting drinking water standards.
KT-20 is a patented filtration media primarily composed of manganese dioxide, which provides both catalytic and adsorptive properties. Its unique features include:
High Surface Area: The porous structure enhances the capacity for contaminant removal.
Long-Term Durability: KT-20 has an extended operational life, reducing the need for frequent media replacements.
Multi-Contaminant Removal: It effectively addresses various contaminants, making it versatile for different water treatment scenarios.
Mechanisms of Contaminant Removal
KT-20 works through several key mechanisms that facilitate the removal of multiple contaminants present in municipal water supplies:
Removal of Iron and Manganese:
– Oxidation: KT-20 catalyzes the oxidation of soluble iron (Fe²⁺) and manganese (Mn²⁺) into their insoluble forms (Fe³⁺ and MnO₂). This process involves the conversion of these metals into solid particulates, which can then be physically filtered out.
– Filtration: Once oxidized, these particulates get trapped within the media bed, leading to significant reductions in iron and manganese concentrations, ensuring compliance with drinking water standards (0.3 mg/L for iron and 0.05 mg/L for manganese).
Removal of Hydrogen Sulfide (H₂S):
– Catalytic Oxidation: H₂S is oxidized to sulfates or elemental sulfur through the catalytic action of manganese dioxide, effectively eliminating the foul odor and taste associated with hydrogen sulfide in the water supply.
Reduction of Turbidity and Suspended Solids:
– Depth Filtration: KT-20 operates as a depth filter, capturing suspended solids and particulates throughout its media. Larger particles are trapped at the surface, while finer particles are captured deeper within the filter, effectively clarifying the water.
– Straining and Coagulation: The media’s structure allows for straining actions that help in the sedimentation of particulates, further enhancing water clarity and reducing turbidity levels.
Adsorption of Organic Compounds:
– Removal of Organics: The high surface area of KT-20 facilitates the adsorption of various organic contaminants, including pesticides, pharmaceuticals, and other pollutants, contributing to improved water quality.
Elimination of Odor and Color:
– Adsorption and Chemical Interactions: KT-20 captures odor-causing substances and colorants through chemical interactions and adsorption, resulting in water that is not only safe but also aesthetically pleasing.
Benefits of Using KT-20 in Municipal Water Treatment
Implementing KT-20 in municipal water treatment facilities offers numerous advantages:
– Comprehensive Treatment: KT-20 removes multiple contaminants effectively, ensuring the production of high-quality drinking water that meets or exceeds regulatory standards.
– Cost-Effectiveness: The long service life of KT-20 results in lower operational costs due to less frequent media replacement and reduced maintenance needs compared to traditional filtration systems.
– Sustainability: By utilizing a natural mineral-based media, KT-20 minimizes the use of harsh chemicals, contributing to a more environmentally friendly water treatment approach.
– Adaptability: KT-20 can be integrated into existing municipal water treatment processes, enhancing overall treatment efficacy without extensive modifications.
KT-20 filter media represents a robust and effective solution for municipal water treatment, addressing a wide array of contaminants, including iron, manganese, hydrogen sulfide, turbidity, organics, suspended solids, odor, and color. By ensuring compliance with drinking water standards and producing safe, palatable water, KT-20 plays a crucial role in safeguarding public health. As communities around the world continue to seek solutions for improving water quality, the integration of advanced filtration technologies like KT-20 will be vital for promoting sustainable and effective municipal water management practices.
