Hydranautics Nitto – RO Membranes – Energy Saving Polyamide – ESPA4 – ESPA4-LD

We ship to
Please login or register to see downloads


Combining energy efficiency with high rejection

The energy required to pressurize RO feed water is the largest contributor to the total energy consumption of the RO plant. ESPA membranes are the choice for applications demanding high-energy efficiency, with uncompromised productivity and salt rejection. Operating at significantly lower pressures, ESPA elements produce high quality water in a range of water treatment applications, ensuring energy cost savings.

ESPA membranes are used in the treatment of drinking water, industrial process waters, municipal and industrial waste water recovery and reuse because of this exception performance capability. These membranes also serve as part of polishing units in seawater desalination plants when boron rejection is critical.

ESPA4 are the lowest feed pressure membranes offering low energy consumption. ESPA4 membranes require ultra-low pressures without compromising high salt rejection and are commonly used in the second pass of a reverse osmosis system.

The ESPA4 membranes are available in the LD variant. Low differential LD Technology models are offered to minimize colloidal fouling when used with conventional pre-treatment equipment. These membranes offer consistently low feed pressures and longer intervals between cleanings.

ESPA4-LD HP are high flux membranes offering low energy consumption without compromising on high rejection. These membranes have an active membrane area of 400 ft2 (37.2 m2), 34 mil brine spacer thickness, and high pressure construction for operation up to 1200 psi (8.27 MPa) to allow greater concentration of feed solution.

ESPA4 membranes are available in the MAX variant with 440 ft2 (40.9 m2) active membrane surface area. Increased membrane area reduces capital costs by requiring fewer pressure vessels and less floor space.





Looking for downloads for this product? Follow the two simple steps below.

Step 1
LoginorCreate Account
Step 2

View downloads!



Manufacturer Hydranautics Nitto
Series Energy Saving Polyamide
Model Number ESPA4
Part Number ESPA4-LD
Description Diameter - 8"
Length - 40"
Permeate Flow - 2,000 gpd
Salt Rejection - 99.2%
Test Conditions -
500 ppm NaCl solution
100 psig Applied Pressure
77 F Operating Temperature
15% Permeate Recovery
6.5 - 7.0 pH Range

Click To Schedule a Service Call

Click To Schedule a Sales Call

Call for a FREE Quote Today

(855) 787-4200