WWTP Process Control
Severe-Cold Instrumentation for Heihe & Shuangliao WWTPs (−40 °C)
1 / 2Project Background
Two municipal wastewater plants in China's far northeast — Heihe (CASS process, 50,000 m³/day) and Shuangliao (A²O+MBR) — face some of the harshest operating conditions anywhere: river-ice seasons of six and four months respectively, with winter temperatures down to −40 °C.
Customer Challenge
Extreme cold freezes and disables ordinary instruments, and low-temperature brittleness causes failures precisely when continuous monitoring is most needed. Both plants required full-process monitoring — MLSS, TSS, dissolved oxygen, pH, ORP, COD, ammonia, total phosphorus, total nitrogen, BOD, level, differential level, gas flow and pressure — that simply keeps working through the long freeze.
The TENGINE Solution
TENGINE deployed 36 instruments of 12 types at Shuangliao and 51 instruments of 11 types at Heihe — MLSS and TSS analyzers, MTU high-precision turbidity, LDO luminescent dissolved oxygen, pH, ORP, COD, ammonia-nitrogen, total phosphorus and total nitrogen analyzers, BOD, B-S gas detection alarms, ultrasonic level and differential-level meters, thermal gas mass flowmeters, electromagnetic flowmeters and pressure transmitters — with heated instrument enclosures available for the severe-cold sites. The Heihe installation was completed in July 2011.
Implementation
The instruments were deployed across the CASS tanks, A²O+MBR units and effluent points, with heated enclosures protecting the installations against the −40 °C winters.
Project Results
Both plants have run their monitoring through year after year of extreme cold without interruption — proving that properly engineered instrumentation keeps data flowing where ordinary equipment freezes, and giving high-latitude cities a proven reference for severe-cold wastewater monitoring.
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