Difference between water types

What is difference between RO water double RO water,portable water,Purified water,distilled water,WFI

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RO systems commonly come in either single-pass or double-pass configurations. One difference is that in a doublepass system that the treated water passes through a membrane twice. Also, in double-pass RO the % recovery and gfd rate are higher than is typical for a single-pass system.

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gfd stand for?membrane pore size?

Flux is used to express the rate at which water permeates a reverse osmosis membrane. Typical units of measurement are gallons per square foot per day (i.e. GFD or GSFD) . The flux of a RO membrane is directly proportional to temperature and pressure.

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Pore size of RO membrane is 0.0005 micron.


thnks well explained.
can u plz explain Sand filter,carbon filter,water softner according to ions or substances removed in ro plant

Sand and Multi-Media filters are used to remove particles from water. Although Sand and Multi-Media are used interchangeably, Sand typically is a single component while Multi-Media is 5 components comprising the bed in the tank.
Sand and Multi-Media Filters can be single tank as well as Duplex and even Triplex depending on requirements.
Sand and Multi-Media Filters can be either Fiberglass, Steel or even Stainless Steel.

Carbon filter- There are two different types of carbon filter cartridges. As we can see, the cartridges are very different. Interestingly enough, the more recent development is the Carbon Block Type Carbon Filter Cartridge because of advances in pulverizing and entrapping carbon in filter media.

Carbon Block Filter Cartridges are used primarily for potable water and also as pre-treatment in water purification systems for removal of taste, odor and chlorine.

The Grannular Activated Carbon Filter Cartridge holds much more carbon by weight and is used in process applications where adsorbing organics is important. Basically we take activated carbon and pour it into plastic containers.



Water Softeners primarily remove hardness from a water supply. Hardness is the collective term for Calcium and Magnesium which are Divalent Cations. Also we have used water softeners for iron and manganese removal – Divalent Cations also.

Water softeners can be single tank as well as Duplex and even Triplex for difficult circumstances.

Water Softeners can also have fiberglass and Steel Tanks.

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Thanks for explaning.
whats about Brine/Nacl charging of ro columns?

RO membranes will inevitably require periodic cleaning, anywhere from 1 to 4 times a year depending on the feed water quality. As a general rule, if the normalized pressure drop or the normalized salt passage has increased by 15%, then it is time to clean the RO membranes. If the normalized permeate flow has decreased by 15% then it is also time to clean the RO membranes. You can either clean the RO membranes in place or have them removed from the RO system and cleaned off site by a service company that specializes in this service. It has been proven that offsite membrane cleaning is more effective at providing a better cleaning than onsite cleaning skids.

RO membrane cleaning involves low and high pH cleaners to remove contaminants from the membrane. Scaling is addressed with low pH cleaners and organics, colloidal and biofouling are treated with a high pH cleaner. Cleaning RO membranes is not only about using the appropriate chemicals. There are many other factors involved such as flows, water temperature and quality, properly designed and sized cleaning skids and many other factors.

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what is the shelf life of water used for sterile preparations?
Mean how long we can store b4 mfg of sterile products

Generally we collect the WFI in manufacturing tank. If WFI is pass from qc we start the batch manufacturing.shelf life of WFI can be validated by taking sample at different time interval and check the how long qc result of wfi is under specification.

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Thanks for all ans.



Sir label claim kese nikalte h