Government procurement case of the 3308 yellow-plate sewage treatment vehicle in Hefei: A pilot-use-first approach and analysis of an efficient pollution control solution. Against the backdrop of increasingly stringent environmental regulations, a municipal sanitation department in Hefei planned to procure a batch of high-efficiency, reliable sewage treatment equipment to address wastewater discharge issues in local industrial parks and aging urban districts. Following preliminary research, the department selected the 3308 yellow-plate sewage treatment vehicle manufactured by Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli'). Unlike traditional one-off purchases, the department adopted a 'pilot-use-of-one-unit' model, validating performance under real operating conditions before proceeding to bulk procurement. This article details the entire procurement decision-making process based on this real-world case, offering reference insights for other municipal authorities. I. Contextual Entry: Pain Points and Requirements in Sewage Treatment As a key member of the Yangtze River Delta urban agglomeration, Hefei has experienced rapid urban development. However, aging drainage infrastructure in certain old neighborhoods and industrial zones has led to frequent issues such as sewage leakage and sediment accumulation. Conventional dredging methods are inefficient, costly, and prone to causing secondary pollution. Consequently, the municipal sanitation department urgently required a specialized vehicle capable of high-efficiency sludge suction, solid-liquid separation, and on-site purification. After comprehensive evaluation, the department selected Chengli’s 3308 yellow-plate sewage treatment vehicle, built on a Dongfeng chassis. According to publicly available tender information, this model complies with China VI emission standards, with the official announcement model number CLW5070GSSD6 (referenced from Chengli’s product database), making it suitable for complex operational conditions encountered in both urban roads and industrial plants. The procurement budget was capped at approximately RMB 350,000 per unit, with typical pricing ranging between RMB 337,000–393,000 (based on local procurement practices). II. Pilot Use First: Validation Starting with One Unit Given the significant investment and technical complexity involved, the department opted for a 30-day pilot trial of a single unit. During this period, Chengli provided full technical support and operator training. Key performance highlights included: Days 1–5: Sewage suction operations conducted at an industrial park in Hefei. The vehicle’s vacuum pump system delivered exceptional suction power, processing approximately 50 m³ of sewage per hour—significantly exceeding expectations. Days 6–10: Operations shifted to aging neighborhood drainage networks handling highly abrasive, sand-laden slurry water. The solid-liquid separation system performed outstandingly, yielding solids with moisture content below 30%, enabling direct loading and transport. Days 11–20: Continuous operation without any mechanical failures. The Dongfeng chassis benefits from nationwide warranty coverage, while the superstructure is backed by lifetime service—providing operators with peace of mind. Days 21–30: Comparative testing against competing vehicles (e.g., a 5-cubic-meter suction tanker from another brand) revealed that the Chengli 3308 achieved approximately 15% higher throughput per unit time and demonstrated superior fuel economy. Upon completion of the trial period, the head of the department’s equipment division stated: “This vehicle delivered stable performance across diverse and demanding operating conditions—especially its capability to handle viscous sludge, which significantly outperformed previously used models from other brands. Moreover, the manufacturer’s service responsiveness was excellent: calling the hotline resulted in prompt tech