On March 27, 2026, the China National Intellectual Property Administration (CNIPA) announced that Suzhou Hengchang Biotechnology Co., Ltd. had been granted a utility model patent for an "environmental protection device for N-methylaniline production wastewater treatment" (《一种N-甲基苯胺生产废水环保处理装置》; authorization announcement No. CN224047052U; filing date April 3, 2025).
The device targets the adsorption stage of N-methylaniline production wastewater treatment. At its core is a resin adsorption tank: a rotatable partition structure inside the tank divides the working space into a loading chamber, a primary filtration chamber, and a secondary filtration chamber, with the primary and secondary chambers connected in series via piping to form a dual-stage series adsorption structure. Driven by the rotating mechanism, the partitions rotate together with the chambers, and the resin adsorbent is transferred between chambers online. During operation, the system only needs to periodically replace resin approaching saturation; the saturated resin is removed and sent to a regeneration unit for reuse. The entire process requires no shutdown, ensuring continuity and operational stability of wastewater treatment.
N-methylaniline serves as a key intermediate in the synthesis of cationic dyes, agrochemicals, and rubber additives; the wastewater from its production is high in pollutant concentration and complex in composition, and resin adsorption is one of the treatment routes commonly adopted in the industry. In a conventional single-train fixed-bed adsorption process, the vessel has to be taken offline to regenerate or replace the saturated resin, making it difficult to keep the treatment system running continuously. Through its structural design, this patent enables resin replacement and regeneration without shutdown, helping improve the operating efficiency of environmental protection facilities — in line with the company's overall direction of green manufacturing and cleaner production.
The company had earlier filed an invention patent application for its N-methylaniline synthesis process. The authorization of this wastewater treatment device further extends the company's technology reserves in environmental protection.
Building on this authorization, the company will continue to increase R&D and investment in environmental protection technology, steadily improve its cleaner production and waste treatment systems, honor its commitment to sustainable development, and create long-term value for customers and society.
(Source: CNIPA patent announcement)