Sequencing of pretreatment technologies

This type of filtration is typically only used on well water sources. In some cases, media filtration is not required prior to greensand filtration. 

Kucera, Jane, Membrane Part 2 The Role of Product Flow Normalization and Membrane Cleaning in RO Operation, UltraPure Water, Vol 22, Number 8, November, 2005. 

Huchler, Loraine, Influent Water Systems, Gulf Publishing Company, Houston, Texas, 2007. 

Jason and Jane Kucera, High-Efficiency Filtration for Membrane Pretreatment, presented at the 68th International Water Conference, October, 2007, paper no. IWC-07-07. 

Activated Carbon, Wikipedia, en.wikipedia.org/wiki/Activated carbon 

Chemical feed this includes chlorine, coagulants, and flocculants. The chemical feeds disinfect the water and prepare it for solids and/or hardness removal. 

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Although sequencing of pretreatment technologies is always site specific, there are some generalizations that can be made. Figure 8.21... 

Although sequencing of pretreatment technologies is always site specific, there are some generalizations that can be made. Figure 8.21 shows a typical process flow diagram that includes many of the pre- treatment technologies described above. Note that most RO systems will not include all of these unit operations. 

Appropriate pretreatment techniques and/or technologies for a given RO application needs to be selected based on the quality of the influent water to be treated by RO. Some water, such as well water with low concentrations of iron and manganese, may require very little, if any, pretreatment, while other water, such as river or lake water, may require extensive pretreatment using sequenced techniques and technologies. 

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