XLP series of extra-low pressure aromatic polyamide compound RO membranes can work under extra-low pressure to reach the same permeate flow as of regular low-pressure membrane elements and achieving rejection of up to 99.0%. XLP series can be effectively used for desalination of low salinity (NaCl ≤1000ppm) surface water, underground water, tap water, and municipal water.
XLP series of membrane elements is particularly applicable to the second-pass desalination with two-pass RO system and is mainly applied to pure water production, boiler water replenishment, foodstuff processing, and pharmaceutical production.
Technical specifications of XLP11-4021 RO membrane
Active membrane area, sq.ft (sq.m)
Average permeate, GPD (cu.m/d)
1 000 (3,78)
Stable rejection rate, %
Min. rejection rate, %
100 psi (0,69 MPa)
Testing solution temperature
Testing solution concentration (NaCl)
Testing solution pH value
Recovery rate of a single membrane element
Operation Limits & Conditions
Max. working pressure
600 psi (4,14 MPa)
Max. feed water supply volume
16 gpm (3,6 m3/h)
Max. feed water temperature
Max. feed water SDI15
Feed water pH Range during continuous operation
3 ≈ 10
Feed water pH Range during chemical cleaning
2 ≈ 12
Feed water residual chlorine concentration
< 0,1 ppm
Max. pressure drop on a single membrane element
15 psi (0,1 MPa)
Max. pressure drop on a single pressure vessel with six RO membrane elements
50 psi (0,34 MPa)
Notes and Recommendations
1. All data and information provided on this site have been obtained from a long-term experiment by the manufacturer of the membrane elements. The manufacturer assumes no liability for any outcomes caused by the user’s failure to abide by the conditions of use and maintenance specified in the product manual. It is strongly recommended that the user strictly follows the designed use and maintenance requirements and keeps relevant records.
2. The permeate value listed in the table is the average value. The permeate flow of a single membrane element has a tolerance not exceeding ±15% of the nominal value.
3. All wet-type membrane elements have been strictly tested before leaving the factory, and have been treated with 1.0% sodium hydrogen sulfite (10% glycerin antifreeze required in winter) for storage purpose, then sealed with a plastic bag in a vacuum, and further packed in cardboard boxes.
4. After being used the membrane element should remain wet. To prevent the breeding of microbes in the idle membranes, it is recommended to soak the membrane elements with a protective solution of 1.0% sodium hydrogen sulfite (foodstuff -purpose) prepared with RO-filtered water.
5. Conduct low-pressure flushing for 15-25 minutes of first use, then high-pressure flushing for 60-90 minutes when first used (with permeate volume no less than 50% of designed volume). Discard all the permeate and condensed water produced during the first hour after the system start-up.
6. During storage time and operation period, it is strictly prohibited to add any chemicals that may be harmful to membrane elements. In case of any violation in adding chemicals, the manufacturer assumes no liability for any incurred damage.
7. Along with technical development and product renovation, all information will be subject to modification without prior notification.