Government Procurement Case and Bid-Winning Solution Analysis for the Dongfeng Yizhan-Style Sewage Treatment Vehicle in Qujing Against the backdrop of accelerated urban environmental governance across Southwest China, demand for sewage treatment vehicles continues to rise. As a key industrial and agricultural base in Yunnan Province, Qujing’s municipal sanitation department recently issued a public tender for a batch of Dongfeng Yizhan-style sewage treatment vehicles targeting urban sewer network and river channel cleaning projects. This article uses this case as a reference, drawing upon Chengli Special Purpose Vehicle Co., Ltd.’s practical delivery experience to deconstruct the vehicle selection logic and solution advantages from an operational condition-matching perspective—providing guidance for similar procurement initiatives. I. Project Background and Scenario Analysis In the second half of 2025, a municipal sanitation department in Qujing launched a procurement project for sewage treatment vehicles, planning to deploy three multi-functional units for urban stormwater-sewer network desilting, pretreatment of industrial wastewater, and emergency river treatment. In line with local procurement practices, the project budget was capped at approximately RMB 1.352 million, with requirements for high maneuverability, strong suction capacity, and an automated control system. Following open tender evaluation, Chengli Special Purpose Vehicle Co., Ltd. secured the contract with its cost-effective solution featuring a Dongfeng chassis integrated with a Yizhan (wing-type) upper assembly—and successfully delivered all three vehicles. This project encompasses three typical operating conditions: 1. Light-Duty Municipal Operations: Cleaning of sewage manholes in narrow urban streets and alleys—requiring small turning radius and compliance with China VI emission standards. 2. Heavy-Duty Industrial Operations: Treatment of heavy-oil-contaminated, high-concentration wastewater at industrial parks and along rivers—necessitating large-capacity tanks and high-power vacuum pumps. 3. Specialized Emergency Operations: Rapid dewatering and solid-liquid separation during emergency response—demanding advanced intelligent control capabilities. II. Operational Condition-Matched Vehicle Selection Strategy To address these three distinct operating conditions, the procuring entity and Chengli’s technical team conducted multiple rounds of parameter comparisons, ultimately finalizing the following configurations (based on parameters published in the Ministry of Industry and Information Technology’s official announcements and Chengli’s product database): 1. Light-Duty Municipal Operations: Dongfeng Dolika D6 Chassis + 4 m³ Tank This model utilizes the Dongfeng Dolika D6 chassis (model CLW5040TWC6), with a wheelbase of 3,308 mm and overall length under 6 meters—ideal for navigating narrow urban roads. The tank offers an effective capacity of 4 m³ and is equipped with a water-ring vacuum pump capable of achieving a maximum suction depth of 8 meters. According to post-delivery feedback from Chengli’s after-sales team, this vehicle averages 10 manhole cleaning operations per day in Qujing’s urban area—demonstrating a 30% efficiency improvement over conventional vacuum trucks. 2. Heavy-Duty Industrial Operations: Dongfeng Tianjin KR Chassis + 8 m³ Tank For high-concentration wastewater in industrial parks, the Dongfeng Tianjin KR chassis (model CLW5180TWCD6) was selected, featuring a 4,500 mm wheelbase and an 8 m³ tank. It employs a dual-pump system (vacuum pump + sewage discharge pump), enabling a maximum suction lift of up to 15 meters. During trial operation at a chemical industrial park in Qujing, this vehicle processed approximately 6 tons of oil-laden sludge per single operation—receiving client feedback stating, “Desilting performance exceeded expectations.” 3. Specialized Emergency Operations: Dongfeng Tianlong VL Chassis + Wing-Type Upper Asse