CPA: High performance membranes for the highest quality water


Hydranautics’ CPA (composite polyamide) membrane elements have become the trusted industry standard for high performance, high purity applications.

CPA elements are available in both 4-inch and 8-inch diameters by 40-inch long spiral wound configurations as well as smaller diameter and shorter length elements for all high purity applications. Our CPA elements can be used as either standalone product or part of our Integrated Membrane Solutions® (IMS) which combines a range of RO, NF, UF and MF membrane technologies to achieve the most comprehensive, effective, low-cost results in the industry.

CPA membranes provide some of the highest salt rejection rates available – every element on every order for every customer.


–       Desalting of well waters for municipal drinking supplies.

–       Reducing TDS (total dissolved solids) prior to ion-exchange.

–       Production of boiler make-up water for power plants.

–       Production of ultrapure water for semiconductor industry.

–       Ultrapure water for pharmaceuticals.

–       Ultrapure water for food and beverage.

CPA Product Offerings:


The product of choice for achieving low TDS product water from brackish water sources.


The element with the best combination of productivity and salt rejection available.


CPA5-LD has the best silica rejection for a brackish water membrane.


The membranes with maximum surface area for enhanced productivity and performance.


4 inch membrane elements for small scale brackish water applications.


A 4 inch membrane element that provides the performance of the CPA5-LD for small scale applications.

Performance for High rejection Membranes:


Selected CPA Project References:

Kill Devil Hills, NC

2 MGD(7,600 m3/d) of potable water from a brackish well water source

Englewood Water District, FL, USA

4 MGD(15,000 m3/d) of potable water from a brackish well water source

Muznib, KSA

3.2 MGD(12,000 m3/d) of potable water from a brackish water source