One in four people globally still lacks access to safely managed drinking water. That figure, published by WHO and UNICEF in August 2025, accounts for 2.1 billion people, including 106 million who drink directly from untreated surface sources.1 Meanwhile, the World Bank reported in November 2025 that the planet loses 324 billion cubic meters of freshwater every year, enough to supply 280 million people annually.2
Desalination and wastewater recycling are two of the most direct responses to this crisis. Both rely heavily on water treatment valves that can handle corrosive fluids, abrasive slurries, and high-pressure environments without failure. When a valve leaks or corrodes prematurely in these systems, the consequences extend beyond equipment damage. They include contaminated water supplies, environmental discharge violations, and lost production capacity.
Reverse Osmosis (RO) desalination works by forcing seawater through semi-permeable membranes at pressures typically ranging from 55 to 70 bar. The feedwater is seawater, which means every valve in the system is exposed to chloride concentrations above 19,000 ppm, along with dissolved oxygen, sulfates, and biological matter.
Standard 316L stainless steel, widely used in general industrial applications, is vulnerable to pitting and crevice corrosion at these chloride levels. Pitting often initiates at surface inclusions or under gaskets where stagnant seawater concentrates. Once a pit forms, it propagates rapidly, compromising the valve's pressure boundary and leading to unplanned shutdowns.
The solution requires a deliberate shift in material specification. Duplex stainless steels (such as UNS S31803 / SAF 2205) offer roughly twice the yield strength of 316L while providing significantly higher resistance to chloride-induced pitting. For the most demanding positions, including high-pressure pump discharge and membrane bypass lines, super duplex grades (such as UNS S32750 / SAF 2507) are specified. These alloys have a Pitting Resistance Equivalent Number (PREN) above 40, compared to approximately 25 for 316L.
The desalination market reflects this growing demand. The global desalination equipment market was valued at approximately USD 18.36 billion in 2024, with a projected compound annual growth rate (CAGR) of 9.6% through 2030.3 The Middle East and Africa accounted for nearly half of global demand, followed by Asia-Pacific at roughly 22%.3
Neway Valve supplies desalinated water control valves for multiple large-scale RO projects worldwide, including the Zuluf Water Treatment Plant and the Escondida Water Supply Project. Neway's in-house foundries, including its precision investment casting facility in Dafeng, produce duplex and super duplex valve bodies with controlled ferrite content and full material traceability from melt to final assembly.
Wastewater treatment presents a different set of challenges. Rather than high pressure and chlorides, the primary concerns here are abrasive suspended solids, biological growth, and aggressive chemical dosing agents.
In primary treatment stages, where raw sewage and stormwater contain grit, rags, and organic solids, the valve must tolerate particulate passage without jamming or seat damage. Resilient-seated butterfly valves are widely used in these applications because their disc design allows solids to pass through the flow path with minimal obstruction. The rubber-lined seat provides a tight seal even after repeated cycling in dirty service.
For sludge handling and dewatering stages, knife gate valves are often the preferred choice. Their sharp-edged gate shears through thick slurries and fibrous material that would block or damage a conventional gate valve. In chemical dosing lines, where acids, alkalis, or disinfectants (such as sodium hypochlorite) are injected, globe valves or diaphragm valves provide the precise flow regulation needed to maintain correct dosing rates.
Check valves also play a critical role throughout wastewater systems. They prevent backflow that could contaminate upstream processes or cause pump damage during shutdown. Combined check butterfly valve with weight-loaded hydraulic actuators, Axial flow check valves and dual plate check valves are favored in larger diameter lines because they produce lower pressure drops than swing check designs, reducing overall pumping energy.
Neway Valve's water treatment product range includes ductile iron resilient gate valves, concentric and double eccentric butterfly valves, axial flow check valves, dual plate check valves, and air release valves. These products are specifically designed for the conditions encountered in municipal and industrial wastewater systems.
Valve reliability in water infrastructure is not just a maintenance concern. It is an environmental and public health issue.
In a desalination plant, a corroded valve on the high-pressure RO feed line can force an unplanned shutdown. Depending on plant capacity, even a 24-hour outage at a large facility producing 500,000 m³/day can leave hundreds of thousands of residents without their primary drinking water source. In regions like the Middle East and North Africa, where desalinated water supplies the majority of municipal demand, such disruptions carry immediate public health consequences.
In wastewater treatment, valve failures carry environmental risk. A leaking isolation valve on a sludge line can release untreated effluent into surrounding soil or waterways. A stuck chemical dosing valve can result in under-dosing, which allows pathogenic organisms to pass through the treatment process. Regulatory penalties for discharge violations can reach millions of dollars, but the environmental damage, including contamination of aquifers and coastal ecosystems, may take years to remediate.
The cost of specifying the correct wastewater treatment valve upfront is a fraction of the cost of a single failure event. Material selection, seal design, and actuator reliability all contribute to long-term performance. For desalination, this means duplex or super duplex bodies with PTFE or metal-seated trim. For wastewater, it means resilient seats, corrosion-resistant coatings, and designs that accommodate solids passage.
Neway Valve's water treatment portfolio spans the full infrastructure chain, from seawater intake and RO processing to potable water distribution and wastewater collection. The company's application expertise covers seawater desalination and transmission, wastewater treatment, potable water distribution, data center cooling systems, and district cooling plants.
With three in-house foundries producing castings in carbon steel, stainless steel, duplex, super duplex, and high-alloy materials, Neway maintains control over material quality from melt stage through final hydrostatic testing. This vertical integration supports the traceability requirements of major EPC contractors and water utility operators worldwide.
Sustainable water infrastructure depends on valves that perform reliably for the full intended service life, typically 25 years or more in municipal applications. Every valve that fails prematurely represents not just a maintenance cost, but a risk to the water supply that communities depend on.
To explore Neway Valve's corrosion-resistant solutions for the water industry, visit our Seawater Desalination and Wastewater Treatment application pages.
World Health Organization and UNICEF. "1 in 4 People Globally Still Lack Access to Safe Drinking Water." WHO, 26 Aug. 2025, www.who.int/news/item/26-08-2025-1-in-4-people-globally-still-lack-access-to-safe-drinking-water---who--unicef.
World Bank. "World Annual Fresh Water Losses Could Supply 280 Million People." World Bank, 4 Nov. 2025, www.worldbank.org/en/news/press-release/2025/11/04/world-annual-fresh-water-losses-could-supply-280-million-people.
Grand View Research. "Water Desalination Equipment Market | Industry Report, 2033." Grand View Research, 2025, www.grandviewresearch.com/industry-analysis/water-desalination-equipment-market.
Mordor Intelligence. "Desalination System Market Analysis | Industry Report, Size & Forecast." Mordor Intelligence, Jan. 2026, www.mordorintelligence.com/industry-reports/desalination-system-market.
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