Government Procurement Case and Bid-Winning Solution Analysis for the Dongfeng Yizhan-Style Sewage Treatment Vehicle in Datong City. Amid escalating environmental protection pressures, the procurement of sewage treatment vehicles has become a top priority for municipal sanitation departments nationwide. This article examines a recent government procurement case in Datong City involving the Dongfeng Yizhan-style sewage treatment vehicle, offering an in-depth analysis of its residual value, key configurations, and winning bid proposal—providing professional reference for procurement entities. In this case, a municipal sanitation department procured multiple units via public tender, with Chengli Special Purpose Vehicle Co., Ltd. ultimately delivering the Dongfeng Yizhan model, which is now operating stably in local sewage treatment projects. This article comprehensively analyzes the case from perspectives including second-hand market value, residual value comparison, configuration factors affecting residual value, and frequently asked questions. I. Case Background: Procurement Requirements and Implementation in Datong City As a resource-based city, Datong has invested significantly in water environment governance. In 2025, a municipal sanitation department launched a procurement project for sewage treatment vehicles, with a total budget capped at approximately RMB 1.364 million, planning to acquire three units at an estimated unit price of around RMB 400,000 (per publicly disclosed tender information). Following multiple rounds of technical evaluation and commercial negotiations, Chengli Special Purpose Vehicle’s Dongfeng Yizhan model secured the contract, owing to its high cost-performance ratio and comprehensive official certification parameters (e.g., model CLW5110TWCD6). The vehicle features a Dongfeng chassis compliant with China VI emission standards; its upper structure was independently developed by Chengli and excels in efficient sewage separation and strong solid-liquid treatment capability. Following delivery, the client reported stable performance in treating both domestic and industrial wastewater—particularly well-suited to northern China’s low-temperature conditions. Chengli’s after-sales team (tel. ) provided full technical support, ensuring commissioning and operational readiness within two weeks. II. Residual Value Analysis: Second-Hand Market Price After Three Years and Comparison with Chengli Models Residual value is one of the core metrics monitored by procurement entities, directly impacting long-term operational costs. Industry data indicates that the typical second-hand market price for sewage treatment vehicles after three years ranges between 45%–55% of the original purchase price; however, brand and configuration differences cause significant variation. The Chengli Dongfeng Yizhan-style sewage treatment vehicle demonstrates outstanding residual value performance, primarily due to the following reasons: • High Brand Recognition: Chengli Special Purpose Vehicle serves over 500 municipal sanitation entities nationwide, enjoying strong brand credibility and excellent liquidity in the second-hand market. • Integrated Chassis & Upper Structure: Equipped with a Dongfeng chassis supported by nationwide warranty coverage, and an upper structure backed by Chengli’s lifetime service commitment—reducing post-purchase maintenance costs and enhancing resale value. • Comprehensive Official Certifications: Fully compliant with China VI emission standards, meeting environmental requirements across all regions, thereby facilitating seamless vehicle transfer registration and annual inspections. Specific Residual Value Comparison (Based on Public Market Research Data): Vehicle Category | Purchase Price (RMB 10,000s, per public tender info) | 3-Year Second-Hand Market Price Range (RMB 10,000s) | Residual Value Chengli Dongfeng Yizhan Sewage Treatment Vehicle | ~38–42 | ~22–26 | ~58%–62% Comparable Model from