10-08-2017, 11:04 AM
I need industrial waste water treatment notes
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10cv835 idustrial waste water treatment vtu notes pdf
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I need industrial waste water treatment notes
16-08-2017, 01:40 PM
Industrial wastewater treatment covers the mechanisms and processes used to treat wastewater produced as a by-product of industrial or commercial activities. After treatment, treated industrial wastewater (or effluents) may be reused or released in a sanitary sewer or in surface water of the environment. Most industries produce some wastewater although recent trends in the developed world have been to minimize such production or to recycle such wastewater into the production process. However, many industries continue to rely on processes that produce wastewater.
Brine Treatment
Brine treatment consists of removing the dissolved salt ions from the waste stream. Although there are similarities to seawater or brackish water desalination, industrial brine treatment may contain unique combinations of dissolved ions such as hardness ions or other metals that require specific processes and equipment.
Brine treatment systems are typically optimized to reduce final flushing volume for more economical disposal (since removal costs are often based on volume) or to maximize recovery of fresh water or salts. Brine treatment systems can also be optimized to reduce electricity consumption, use of chemicals, or physical footprint.
Brine treatment is commonly encountered when treating cooling tower purge, water produced by steam assisted gravity drainage (SAGD), water produced by the extraction of natural gas such as carbon sewing gas, - sewage, pulp and paper effluents, and waste streams from food and beverage processing.
Brine treatment technologies may include: membrane filtration processes, such as reverse osmosis; Ion exchange processes such as electrodialysis or weak acid cation exchange; O evaporation processes, such as brine concentrators and crystallizers which employ recompression of mechanical steam and steam.
Reverse osmosis may not be viable for the treatment of brine due to the potential for fouling caused by salts of hardness or organic contaminants or damage to reverse osmosis membranes from hydrocarbons.
Evaporation processes are the most widespread for the treatment of brine because they allow the highest degree of concentration, as high as the solid salt. They also produce the highest purity effluent, including the quality of the distillate. Evaporation processes are also more tolerant of organic, hydrocarbon or hardness salts. However, energy consumption is high and corrosion can be a problem since the main engine is concentrated salt water. As a result, evaporation systems typically employ titanium or duplex stainless steel materials.
Removal of solids
Most solids can be removed using simple settling techniques with recovered solids as slurry or slurry. Very fine solids and solids with densities close to the density of water pose special problems. In such a case, filtration or ultrafiltration may be required. Although, flocculation can be used, using alum salts or the addition of poly-electrolytes.
Removal of toxic materials
Toxic materials, including many organic materials, metals (such as zinc, silver, cadmium, thallium, etc.), acids, alkalis, nonmetals (such as arsenic or selenium) are generally resistant to biological processes unless highly diluted . Metals can often precipitate by changing pH or by treatment with other chemicals. Many, however, are resistant to treatment or mitigation and may require concentration followed by landfill or recycling. Dissolved organic materials can be incinerated into the wastewater by the advanced oxidation process.
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