Hydranautics CPA5-LD 8040 is a low-fouling, high-rejection brackish-water RO spiral-wound membrane (400 ft²) delivering ~11,000 gpd and ~99.7% salt rejection — ideal for industrial, municipal and high-purity applications.
The Hydranautics CPA5-LD 8040 is a fourth-generation, high-rejection brackish RO element engineered
Performance & Technical Highlights
Nominal permeate: 11,000 gpd (41.6 m³/day) — high throughput for 8040 elements.
Salt rejection: 99.7% (99.6% min) — excellent for brackish water desalting, ultrapure water polishing and critical industrial processes.
Membrane area: ~400 ft² (≈37 m²) per element; feed spacer 34 mil to improve cleaning efficiency and reduce fouling frequency.
Operating limits: Max pressure 600 psig (4.16 MPa), max temp 113 °F (45 °C). Continuous pH 2–11 (cleaning up to pH 1–13 per Hydranautics cleaning guidelines).
Hydraulic notes: Max feed flow about 75 GPM (17 m³/h) per element; maximum allowable pressure drop per element ≈ 10–15 psi depending on model family.
Why choose CPA5-LD 8040
Highest salt rejection: Ideal where low TDS and silica/nitrate control matter — power plants, pharma, semiconductor or boiler feedwater.
Low-fouling LD design: 34-mil feed spacer + optimized geometry reduces fouling and improves cleanability, lowering chemical cleaning frequency and lifecycle cost.
Space & capital efficiency: Large active area reduces number of vessels required versus older elements, saving skid footprint and initial CAPEX.
Proven global pedigree: CPA family is widely used in municipal and industrial plants — extensive field track record.
Typical Applications
Brackish water desalination & municipal drinking water pretreatment
Boiler feedwater and power plant make-up water
Pretreatment or polishing for ultrapure water in pharmaceutical, microelectronics & semiconductor fabs
Industrial process water where silica, hardness and TOC control are needed
Installation, Operation & Maintenance Notes
Follow manufacturer start-up and normalized test conditions when comparing element performance (Hydranautics uses 1,500 ppm NaCl, 225 psi, 77°F at 15% recovery for standard rating).
Maintain feed SDI ≤5 and turbidity ≤1 NTU to protect element life; the LD design is more tolerant to suspended solids but still benefits from good prefiltration.
Avoid exposure to free chlorine >0.1 ppm; composite polyamide membranes are chlorine sensitive. Store elements per supplier instructions (often in sodium meta-bisulfite solution inside sealed bag).
Observe recommended cleaning pH and procedures
5 Short “Why Buy” bullets for product card (conversion)
99.7% salt rejection — industry-leading brackish RO performance.
11,000 gpd nominal flow — high throughput 8040 element.
Low-Fouling LD feed spacer (34 mil) — fewer cleanings, lower OPEX.
400 ft² active area — fewer elements and smaller footprint.
Proven Hydranautics CPA family — trusted in power, pharma & municipal plants.