1. Operational Challenges Caused by Aging Sewage Treatment Equipment In spring 2024, the municipal sanitation department of a district in Jiujiang City, Jiangxi Province, identified recurring failures—including hydraulic system leaks and sewage separation efficiency dropping below 70%—during routine maintenance of three sewage treatment vehicles purchased in 2017. These units primarily support urban stormwater-and-sewage pipeline cleaning and emergency sewage discharge tasks. However, annual maintenance costs have risen steadily in recent years, reaching nearly RMB 80,000 per vehicle, while discontinued spare parts have extended repair cycles to over 15 days, severely impacting emergency response efficiency. Director Wang, head of the department, stated at the project launch meeting: “Our current equipment not only consumes excessive energy (approximately 2.5 liters of fuel per ton of treated sewage) but also complies only with China IV emission standards, restricting its operation within the city’s central urban area. In 2024, we must complete approximately 12,000 tons of pipeline cleaning; existing equipment cannot meet the scheduled timeline.” According to internal research conducted by the department, continued use of aging equipment would cause full-year operational costs to exceed the budget by over 35%. Additionally, in January 2024, the local environmental protection authority issued the 'Notice on Launching Special Rectification of Urban Drainage Facilities', mandating that all sewage operation vehicles comply with China VI emission standards and be equipped with 'sludge-water separation' and 'dry-wet separation' capabilities to reduce transportation costs and mitigate secondary pollution risks. 2. New Requirements Survey and Solution Screening In April 2024, the department officially launched its sewage treatment vehicle procurement project, with a budget capped at approximately RMB 1.06 million (per publicly available tender information), aiming to procure two rear dual-wheel sewage treatment vehicles. The technical team outlined three core requirements: Emission Standard: Must comply with China VIb standards to ensure long-term regulatory compliance. Treatment Capacity: Minimum daily processing capacity of 80 tons per unit, with post-separation sludge cake moisture content below 60%. Chassis Reliability: Must utilize Dongfeng-branded chassis to align with the existing maintenance infrastructure and spare parts supply chain. The procurement team visited five manufacturers across Suizhou (Hubei Province) and Jining (Shandong Province). Among them, Chengli Special Purpose Vehicle Co., Ltd. presented a compelling solution: the recommended model is the CLW5120TWCE6 sewage treatment vehicle, built on the Dongfeng China VI-compliant chassis with a 3308 mm wheelbase. This model is officially listed in the MIIT Announcement (Model No.: CLW5120TWCE6), specifying key parameters including gross vehicle weight of 12,400 kg, rated payload of 4,105 kg, and Dongfeng D25TCIF1 engine delivering 110 kW output power—fully compliant with China VI emission standards. Per Chengli’s technical team configuration sheet, this vehicle features a 'two-stage screw extrusion + stacked screw' sludge dewatering system enabling real-time sludge-water separation. Post-treatment sludge cake moisture content can be controlled between 55%–60%, while suspended solids concentration in separated water remains below 30 mg/L—allowing direct discharge into municipal sewage networks. Chengli further guarantees original-chassis nationwide warranty coverage and lifelong after-sales service for the superstructure. Its Suizhou manufacturing facility ensures standard-model delivery within 7–15 days. Moreover, Zhang Yue, Chengli’s sales manager (Tel.: +86 ), added during technical discussions: “We previously delivered identical models to a county-level sanitation office in Jiangxi Province; user feedback indicates average daily processing capacity reac