In Jianshi County, surrounded by the mountains of western Hubei, the Hongtuping Water Treatment Plant sits at an altitude of 1,100 meters, like a "natural water tower" suspended above the city. In 2023, after the completion of this 50-million-yuan renovation and expansion project, the county's water supply capacity jumped from 50,000 tons per day to 75,000 tons. With a disruptive technological innovation — three Krupp permanent magnet variable frequency oil-free screw blowers + a COD online linkage system — the plant achieved a milestone breakthrough in the history of gravity-flow water supply in mountainous areas. Operating entirely under a "zero-pumping" mode that relies on terrain drop for natural flow, the plant has stabilized effluent turbidity below 0.1 NTU, achieved a 100% pass rate for microbial indicators, and reduced filter backwash energy consumption by 45% year-on-year.

The Shenduhe Sewage Treatment Plant construction project is a sub-item of the Yangtze River Protection Project in Xingshan County, undertaken by the Three Gorges Base Development Company. The project commenced in May 2019, covering an area of 25 acres with a total investment of 210 million yuan. It includes the construction of 9.5 kilometers of main sewage collection pipelines and has a designed treatment capacity of 20,000 tons per day. The process adopts "improved AAO + advanced treatment," and the effluent quality meets the Class A discharge standard. In July 2020, the project procured three Krupp oil-free screw blowers, which passed commissioning and began operation in December of the same year, with satisfactory performance. The project has enabled "full collection, full treatment, and full compliance" of domestic sewage from Xingshan county seat and three surrounding administrative villages, effectively improving the water environment quality of the Xiangxi River Basin and ensuring clean water flows into the Yangtze River.

The Laohekou No.2 Water Plant Capacity Expansion and Quality Improvement Project, as one of the municipal government's "Top Ten Livelihood Projects," has a total investment of 41.4 million yuan. The project covers an area of 6,667 square meters and can treat up to 60,000 tons of water per day. It adopts a core process consisting of a folded plate flocculation tank + horizontal flow sedimentation tank + V-type filter, thoroughly solving the pain points of "aging processes and fluctuating water quality" that had troubled residents for many years. In this water quality upgrade battle, three Krupp oil-free screw blowers, with their excellent performance, have become the "invisible guardians" ensuring efficient filter operation and high-quality water supply. In July 2021, the water plant procured three Krupp oil-free screw blowers from our company, which passed commissioning and began operation in September of the same year, with satisfactory performance.

In Daying Town, Hengshui, Hebei Province — the "Hometown of Fur in China" — a wastewater treatment plant shouldering environmental responsibility is quietly transforming behind the prosperity of the leather industry. The Daying Wastewater Treatment Plant upgrading and renovation project has a daily treatment capacity of 25,000 m³. It was undertaken as an EPC general contracting project by Beifang Ecological Environment Municipal Engineering Technology Co., Ltd. Facing the stringent standard upgrade from Class 1-B to Class 1-A (especially with ammonia nitrogen ≤ 2mg/L and total phosphorus ≤ 0.4mg/L), the aeration system of its core process — the oxidation ditch — became the key to breaking through the bottleneck. In 2020, the roar of six Krupp outdoor-type oil-free screw blowers replaced the harsh noise of traditional Roots blowers, delivering a triple transformation of "low energy consumption, quiet operation, and high stability," creating a vivid model for wastewater standard upgrading in northern industrial towns.

At the foot of Mount Wutai, upstream of the Hutuo River, a "quiet energy revolution" is taking place at the Wutai County Sewage Treatment Plant. This county-level plant, which treats 25,000 tons of domestic sewage and tourism wastewater per day, was once trapped in the dilemma of balancing "compliance" and "cost reduction." In July 2020, four Krupp permanent magnet variable frequency oil-free screw blowers replaced the roaring traditional Roots blowers. Not only did they achieve a comprehensive energy saving rate of over 25%, setting a new industry benchmark, but they also delivered a compelling economic case of "recovering the incremental investment within two years," providing a replicable "Wutai model" for energy-saving renovations in northern county-level sewage treatment plants.