The Challenge
A hydrogen-rich waste stream — and a campus already paying for hydrogen.
Wintinwe’s chlor-alkali operation produces a continuous stream of waste gas: roughly 95% hydrogen, 4% water, and 1% nitrogen, CO2, and other contaminants. Untreated, it’s a low-value byproduct. Meanwhile, the same site needed reliable, five-nines hydrogen for three different uses — a steel blanketing atmosphere, chemical processing, and tube-trailer filling for merchant sales through Rishion Gas.
The molecule was already on site. The problem was scrubbing it to pipeline grade — 99.999% H2, 0.0002% O2, −65 °C dew point — every hour, for years, without a babysitter. And the system needed to flex: feedstock supply could change, downstream demand could grow, and the plant had to absorb both without disruption.
Customer Pain Points
Valuable hydrogen, locked in a waste stream
Three downstream users, one purity floor
Steel blanketing, chemical processing, and merchant tube-trailer filling all demand 99.999% purity — no margin for variability.
Minimal staffing, maximum reliability
Continuous chemical operations can’t carry a large crew to nurse the plant — and downstream lines can’t tolerate unplanned downtime.
What Hydrexia Delivered
An integrated, automated purification train — built for flexibility, instrumented for remote control.
Hydrexia designed and delivered a complete PSA-plus-TSA purification system, sized for the waste-gas volume and tuned to the campus’s downstream specs. Raw waste gas (95% H₂, 4% H₂O, 1% N₂/CO₂/other) enters a buffer with integral water knockout, is compressed to 18 bar, and moves through a six-vessel PSA train — one in processing, six in regeneration — to strip out the bulk impurities.
From the PSA, the stream passes through two thermal swing adsorption (TSA) stages — first for residual oxygen removal (deoxo), then for final drying — and into H₂ buffer storage before being delivered to:
- 85–90% of output → on-campus pipeline to steel blanketing and chemical processing
- 10–15% of output → merchant tube-trailer filling (Rishion Gas)
PSA tail gas isn’t wasted either: it’s routed to the site boiler to generate steam, improving overall site efficiency.
The whole system runs under 24/7 remote monitoring, with automation built specifically to reduce on-site manpower and leave room for future expansion. When the upstream waste-gas supply was briefly unavailable, the site switched to a lower-purity hydrogen feed — Hydrexia verified compatibility, approved the change, and the plant kept running. That’s real-world flexibility, not just design flexibility.
The outcome
Nine Years. Zero Failures.
Preventive maintenance on process controls. Deoxo media replaced once. Everything else just runs.
"Carefree Operation."
Chongqing Wintinwe Chlor-Alkali Chemical Company, Ltd.