Gravel, Graduated Sand And Anthracite.
Iron and Manganese Removal Media.
- Sand filtration is a frequently used very robust method to remove suspended solids from water.
- The filtration medium consists of a multiple layer of sand with a variety in size and specific gravity.
-APPLICATIONS FOR SAND FILTRATION:
- Pre-peration of cooling water.
- Treatment of waste water.
- Production of drinking water.
- Filtration in swimming pools.
- Pre-filtration for membrane systems.
- Filtration of grey or surface water.
- Removal of iron.
-A sand filter has a dirt holding capacity of 3 to 6 kg TSS / m2 of sand surface.
-When the filters are loaded with particles, the flow direction is reversed and the flow is increased to clean the filter again. This step is called a backwash.
IRON REMOVAL PLANTS
- Can be based on different filtration media, depending on the iron and manganese concentration, the oxygen level, CO2 content and hardness of the water.
- First, air is injected in order to oxidize the iron. The oxidized iron will then precipitate on a sand filter. An MnO2 layer in the sand bed will catalyze the oxidation of residual iron. Backwash will be done by water and by air. More on
IRON AND MANGANESE
- Are unaesthetic parameters present mostly in groundwater, causing unwanted precipitation and color.
- Iron removal is based on the precipitation of dissolved iron (Fe2+) into its oxidized form (Fe3+), as Fe(OH)3 or Fe2O3.
- Iron removal by physical-chemical way consists in iron oxidation by air followed by sand filtration:
- is used to purify liquids and gases in a variety of applications, including municipal drinking water, food and beverage processing, odor removal, industrial pollution control.
- Activated Carbon is produced from carbonaceous source materials, such as coconuts, nutshells, coal, peat and wood.
- The primary raw material used for activated carbon is any organic material with a high carbon content.
- Depending on the type of water, suspended solids concentration, oil and grease, COD, BOD and pesticides contents.
- For pesticide removal only at averal occurence at ppb levels, lifetime of an activated carbon bed can be up to 10 years. For natural organic matter or oil and grease, bed renewal can vary from few weeks to few years.
Adsorption is a process where a solid is used for removing a soluble substance from the water. In this process active carbon is the solid. Activated carbon is produced specifically so as to achieve a very big internal surface (between 500 – 1500 m2/g). This big internal surface makes active carbon ideal for adsorption. Active carbon comes in two variations: Powder Activated Carbon (PAC) and Granular Activated Carbon (GAC). The GAC version is mostly used in water treatment, it can adsorb the following soluble substances:
-ADSORPTION OF ORGANIC, NON-POLAR SUBSTANCES SUCH AS:
- Mineral oil
- Poly aromatic hydrocarbons (PACs)
- (Chloride) phenol
-ADSORPTION OF HALOGENATED SUBSTANCE:
- I, Br, Cl, H en F
ACTIVATED CARBON ADSORPTION
- Adsorption is a process where a solid is used for removing a soluble substance from the water. In this process active carbon is the solid. Activated carbon is produced specifically so as to achieve a very big internal surface (between 500 – 1500 m2/g). This big internal surface makes active carbon ideal for adsorption. Active carbon comes in two variations: Powder Activated Carbon (PAC) and Granular Activated Carbon (GAC). The GAC version is mostly used in water treatment,
WHAT IS THE DIFFERENCE BETWEEN ADSORPTION AND ABSORPTION?
- When a substance is attached to a surface is is called adsorption, is this case the substance is attached to the internal surface of active carbon.
- When a substance is absorbed in a different medium it is called absorption. When a gas is taken in a solution it is called absorption.
- The Greensand process for the removal of iron, manganese and hydrogen sulfide from groundwater is an enhancement to the original Manganese Greensand process which has been effective in the removal of arsenic and radium as well. Historically, the original Manganese.
- iron and manganese removal.
The mechanism for iron and manganese removal by Greensand in the CO mode is oxidation.
ph Filters – Calcite is crushed and screened white marble media which can inexpensively be used to neutralize acidic or low pH waters to a neutral, less corrosive effluent. Calcite is a naturally occurring calcium carbonate media. One of the advantages of Calcite is its self-limiting property. When properly applied, it corrects pH only enough to reach a non-corrosive equilibrium. It does not over correct under normal conditions.
Upon contact with Calcite, acidic waters slowly dissolve the calcium carbonate to raise the pH which reduces the potential leaching of copper, lead and other metals found in typical plumbing systems. Periodic back washing will prevent packing, reclassify the bed and maintain high service rates. Depending on pH, water chemistry, and service flow, the Calcite bed will have to be periodically replenished as the Calcite is depleted.