Lanzhou Petrochemical: Production increased, but water usage actually decreased?

On March 25 at 8:30, inside the computer room of the exterior operator office for the ethylene circulating water installation in the public utilities engineering second division’s air separation sub-system water-supply area of Lanzhou Petrochemical, the numbers with yellow-and-green bands on the screen danced lightly.

“On this shift, the average make-up water quantity for the cooling tower B’s collecting tank dropped by another 2 tons per hour.” Chen Keran,班长 of the Chemical Section’s Third Shift, let the corner of his mouth curl slightly upward. Wang Fei,班长 of the Second Shift who was handing over with him, took the logbook and replied with a smile: “This shift you all have stayed ahead. For our next shift, we’ll definitely catch up!”

A few relaxed lines of conversation—no showdown with sword drawn and no outward tension—yet they hid the drive to learn from and compete with each other. This is also a vivid snapshot of Lanzhou Petrochemical’s “small-parameter competition” focused on saving water, improving quality, and boosting efficiency. Average make-up water quantity by crew, circulating water concentration ratio, water-quality compliance rate… every metric is broken down to crews and quantified to individuals. The data are no longer cold numbers, but a默契 of saving water as crews chase one another.

Such “water-saving scenarios” have become the norm rather than an exception across all production areas at Lanzhou Petrochemical. Since this year began, a series of “major battles” for water saving and emission reduction have been in full swing. Everyone is a protagonist in water saving and emission reduction, and careful calculations can be seen everywhere.

At the Yulin Company, operators have woven “saving water and reducing consumption” into every inspection and every operation. With precise, fine-grained management, they have built a water-saving defense line. The ethylene water intake is only 1.89 cubic meters per ton—far below the national standard of ≤12 cubic meters per ton. It not only sets an industry benchmark for green development, but also places the water-efficiency level at the top nationwide among ethane-feed ethylene categories.

Water-use management in the Rubber Department is moving from “coarse handling” to “micro-operations.” Through a strategy of “phased advancement, full-scale promotion,” they are pushing hard the retrofit project for reusing filter water from drying-immerser washing. At present, the filtered water used for the washing of the near “zero-consumption” of the 1.5×10^4-ton/year nitrile rubber plant’s凝聚 system has achieved near “zero consumption.”

“Previously, I always felt that water was ‘public property,’ so using a bit more didn’t really matter. But now it’s different—every ton of water affects the crew’s ‘face’ and ‘substance.’” said Tong Xiying,班长 of the Third Shift of the凝聚 section, smiling.

To manage water scientifically and control it, we also need to innovate thinking and open up “new water.” Walking into the oil refining and purification water area of Lanzhou Petrochemical’s public utilities engineering first division, the newly put into operation deep-treatment unit—No. 6 reverse osmosis unit—is running efficiently. With a logbook in hand, Shi Ran Tao, a third-level engineer of the unit, moves slowly along the inspection route. At the water production sampling port, he turns the valve—clear water gushes out, and as it flows into the sampling bottle, fine foam forms. He lifts the bottle up in front of his eyes to examine it carefully in natural light, then takes out the handheld testing instrument he carries and gently taps it. “The conductivity is 15 microsiemens per centimeter, far below the design standard.” He records this sequence of numbers seriously in his notebook.

Before that, the oil refining and purification water area had already operated five sets of similar deep-treatment units. But as the production load increases, there are times when fresh-water output is occasionally “in short supply.” Now, with the optimized operating pattern of “5 in use, 1 on standby,” the six deep-water treatment units complement one another and can be flexibly deployed. This not only boosts fresh-water output substantially, but also brings a remarkable benefit of saving 600k tons of fresh water per year.

Lanzhou Petrochemical’s 2025 oil-refining area desalinated water system optimization project, built and put into operation, also highlights strong benefits. Upgrades to the raw-water pretreatment process and the backwashing water reuse technology increase the backwashing water reuse rate from under 80% previously to 95%. The specific water consumption for water production also drops from 1.26 tons/ton to 1.18 tons/ton. Annually, it can save 480k tons of fresh water and reduce costs by more than 14.10 million yuan.

From top-level design to front-line actions, from upgrades in management mode to innovation in technical processes, this all-staff water-saving campaign by Lanzhou Petrochemical has released an eye-catching “value-driven multiplier” effect.

“In the first quarter, with a significant increase in product output such as ethylene, polyolefins, and rubber, the units’ total water saving reached 131.4k tons, with the saved amount up 7.31% year-on-year.” said Wu Zhaodong, head of the energy (water intake and use) management group of Lanzhou Petrochemical’s production and operations department, with pride. (Source: Lanzhou Petrochemical Company)