Seawater Desalination: A Chinese High-Pressure Pump Enters Commercial Plants
A Weihai-built duplex-steel high-pressure pump is running in commercial desalination plants in Qingdao and Zhoushan, and a Dongying plant reports 50,000 tonnes of desalinated water a day — a domestic-substitution record for a component long supplied from abroad.
Lead
A high-pressure pump developed in China for seawater reverse-osmosis desalination has entered commercial service at plants including Qingdao and Zhoushan, Dazhong Daily (大众日报) reported on 22 September 2026, with the manufacturer describing three to four years of continuous operation.
Facts
The duty. In a seawater reverse-osmosis plant, the high-pressure pump pushes the feed against the membrane, and both reports describe it as the plant's core item of equipment — one they say was long dependent on imports. (Sources: Dazhong Daily, 2026-09-22; Shandian News (闪电新闻), 2026-09-14.)
The maker and the casting problem. Shandong Shuanglun Co., Ltd. worked from 2507 duplex stainless steel as the casing material; the newspaper's account describes crack defects that can appear if the cooling rate is not controlled in the high-temperature stage of casting, and a high-temperature shake-out process adopted to avoid them. Hydraulic design was iterated through multi-physics flow simulation followed by prototype testing. (Source: Dazhong Daily.)
The platform behind it. The district science and technology bureau in Huancui, Weihai (威海市环翠区科学技术局) guided the establishment of a provincial technology-innovation centre for desalination fluid equipment and supported the company's application for a provincial major scientific and technological innovation project, according to the newspaper. The pump won a provincial marine science and technology innovation first prize. (Source: the same.)
The running record. The company's general manager, quoted by the newspaper, describes continuous runs of three to four years, with users replacing wear parts at overhaul intervals; the pumps are also reported in chemical-plant and power-plant saline-water duties. (Source: the same.)
An operating user. At Dongying Port, a phase-I plant of Shandong Nahai Water Development Co. (山东纳海水务发展有限责任公司) produces 50,000 tonnes of desalinated water a day, with a full-load capability of 18 million tonnes a year, and the plant reports saving more than 26 million tonnes of freshwater a year for over 200 petrochemical enterprises in the development zone; a domestic high-pressure pump had just been installed and commissioned in its workshop, Shandian News reported on 14 September 2026. (Source: Shandian News.)
The province context. Shandong's desalination capacity stands at 964,000 tonnes a day, nearly one-third of the national total and the largest of any province, according to Haibao News (海报新闻), which names the high-pressure pump, the energy-recovery device and the reverse-osmosis membrane as the three components the province pushed to localise; a 2024 provincial key research and development project on wide-range, high-efficiency desalination high-pressure pump technology was undertaken jointly by a research team and Shandong Shuanglun among others. (Source: Haibao News.)
Where this connects on this site
- Why a chloride duty is read against a material grade and a temperature together, not against a steel's name: Chemical Compatibility Chart for Pumps: What the Grade and the Temperature Actually Mean
- Where a high-pressure multistage centrifugal duty sits against the positive-displacement boundary: Centrifugal vs Positive Displacement Pumps: What the 500 cP Line Really Means
- The selector: chempumpselect.com
Sources
| # | Fact | Source |
|---|---|---|
| 1 | The pump's entry into commercial service at Qingdao, Zhoushan and other projects; the 2507 duplex stainless casting problem and the high-temperature shake-out process; multi-physics simulation plus prototype iteration; the district science and technology bureau's role in the provincial innovation centre and the major sci-tech project; the provincial marine sci-tech innovation first prize; the general manager's statement of three-to-four-year continuous runs; use in chemical-plant and power-plant saline-water duties | 大众日报（大众新闻客户端，经腾讯新闻转载）, 2026-09-22 — https://new.qq.com/rain/a/20260922A08EKG00 |
| 2 | The Dongying Port plant: phase-I output of 50,000 tonnes of desalinated water a day, full-load capability of 18 million tonnes a year, more than 26 million tonnes of freshwater saved a year for over 200 petrochemical enterprises; a domestic high-pressure pump newly installed and commissioned in the plant's workshop | 齐鲁网·闪电新闻, 2026-09-14 — https://sdxw.iqilu.com/share/YS0yMS0xNzM5NTc2NQ.html |
| 3 | Shandong's desalination capacity of 964,000 tonnes a day, nearly one-third of the national total; the three localisation targets (high-pressure pump, energy-recovery device, reverse-osmosis membrane); the 2024 provincial key R&D project on wide-range high-efficiency desalination high-pressure pumps undertaken jointly with Shandong Shuanglun | 海报新闻（大众网） — https://w.dzwww.com/p/p4LxjErefGe.html |
Note on sourcing. This item reports party-newspaper and broadcaster accounts of a manufacturer's product record. We record the verifiable layer — the plants named, the materials and processes described, and the operating figures as quoted. Performance statements attributed to the manufacturer are reported as such, and we do not rank or recommend suppliers.
What the source does not state
The reports do not state the pump's model, flow, discharge pressure or efficiency, the names of the imported equipment it replaces, the number of units delivered, prices, the energy-recovery device and membrane suppliers, or measured energy consumption per cubic metre of water produced.
Update note
This item is a dated record of publicly reported manufacturing and operating milestones. We append corrections rather than rewrite history; corrections are marked Correction with the date.