Payment & Shipping Terms:
|Stable Rejection::||96~98%||Type:||Water Filter Parts|
|Color:||Can Be Customize||Function:||Producing Fresh Water|
|Filter Precision:||0.0001 Micron||Capacity:||50GPD|
A membrane is a thin layer of semi-permeable material that separates substances when a driving
force is applied across the membrane. Membrane processes are increasingly used for removal of
bacteria, microorganisms, particulates, and natural organic material, which can impart color,
tastes, and odors to water and react with disinfectants to form disinfection byproducts.
As advancements are made in membrane production and module design, capital and operating
costs continue to decline. The membrane processes discussed here are microfiltration (MF),
ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO).
Microfiltration is loosely defined as a membrane separation process using membranes with a
pore size of approximately 0.03 to 10 micronas (1 micron = 0.0001 millimeter), a molecular
weight cut-off (MWCO) of greater than 1000,000 daltons and a relatively low feed water
operating pressure of approximately 100 to 400 kPa (15 to 60psi) Materials removed by MF
include sand, silt, clays, Giardia lamblia and Crypotosporidium cysts, algae, and some bacterial
species. MF is not an absolute barrier to viruses. However, when used in combination with
disinfection, MF appears to control these microorganisms in water.
There is a growing emphasis on limiting the concentrations and number of chemicals that are
applied during water treatment. By physically removing the pathogens, membrane filtration can
significantly reduce chemical addition, such as chlorination.
Another application for the technology is for removal of natural synthetic organic matter to
reduce fouling potential. In its normal operation, MF removes little or no organic matter;
however, when pretreatment is applied, increased removal of organic material can occur. MF
can be used as a pretreatment to RO or NF to reduce fouling potential. Both RO and NF have
been traditionally employed to desalt or remove hardness from groundwater.
Ultrafiltration has a pore size of approximately 0.002 to 0.1 microns, an MWCO of
approximately 10,000 to 100,000 daltons, and an operating pressure of approximately 200 to 700
kPa (30 to 100 psi). UF will remove all microbiological species removed by MF (partial removal
of bacteria), as well as some viruses (but not an absolute barrier to viruses) and humic materials.
Disinfection can provide a second barrier to contamination and is therefore recommended.
The primary advantages of low-pressure UF membrane processes are compared with
conventional clarification and disinfection (post-chlorination) processes are:
• No need for chemicals (coagulants, flocculants, disinfectants, pH adjustment)
• Size-exclusion filtration as opposed to media depth filtration
Contact Person: Carey Gao