This study about waste-water treatment processes, the main objectives of this project were to identify the nature and sources of waste-water in Palestine, to study the waste-water treatment processes which include primary, secondary, advanced stages and to study the biological treatment technology used in diary product (Whey).
Two waste-water treatments in Palestine were visited, first in Ramallah "Beituniya" and the other in Al-Bireh. Also the Palestinian Ministry of Environmental Affairs in Nablus, Water Authority & Environment and the Centre for Statistics in Ramallah were visited to identify the characteristics of waste-water and its sources in Palestine and to collect detailed information about Whey.
Obvious conclusion that was reached after this study for the project that waste-water is not only sewage as common in the thinking of many people but it also produced from many sources, such as dwellings, commercial or industrial facilities and institutions, in addition to any ground water, surface water and storm water.
Waste-water varies according to source in the characteristics of COD and BOD. Waste-water generated by food industries, especially resulting from whey has high BOD = 14000 mg/L because it contains high amounts of protein and high COD = 21100 mg/L because it contains sugar.
There were several methods used in the treatment of waste-water, including Primary treatment, Secondary treatment, and Advanced treatment. These processes help to obtain the largest possible quantity of treated water to use in many applications such as in agriculture, paving the streets and Building.
As for the whey, there are several ways to treat whey which include Anaerobic treatment, Aerobic treatment, membrane methods, microfiltration, ultra filtration, nano filtration, reverse osmosis, ion exchange, electro dialysis and others.
Within this study it is found that the best way is anaerobic treatment because it reduces the emission of landfill gas into the atmosphere, used as a renewable energy source because the process produces methane and carbon dioxide, helping to replace fossil fuels, the nutrient-rich digestate which is also produced can be used as fertilizer and the digested solids are generally free of objectionable odors.
But there were many disadvantage of anaerobic treatment as the capital cost is high because large closed digestion tanks fitted with systems for feeding, heating, and mixing the sludge are required. Large reactors are required to provide the hydraulic detention time in excess of 10 days to stabilize the sludge effectively, and microorganisms involved in anaerobic digestion are sensitive to small changes in the environment.