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The heat carried away by the waste gas from the coke oven accounts for 36% of the total heat generated by the oven. Due to technical limitations, this heat has not been recovered over the years; instead, it is cooled by spraying large amounts of circulating ammonia water at 70–75°C. The temperature of the waste gas varies periodically between 450–850°C; its composition is complex, containing large amounts of dust, tar, water vapor, benzene vapor, H2S, etc. If the temperature of the rising pipe (the heat-exposed surface) is too low, the tar will condense and block the upward flow path. At high temperatures, carbon deposits can form as well as graphite, which can also cause corrosion, making recovery difficult. Through close cooperation between Tianjin Huaneng and Jiangsu Longye, and after repeated pilot tests, China’s first waste heat recovery system for raw gas was successfully developed. It was put into industrial use in February 2014 at the 2x65-hole, 4.3-meter coke ovens of Fujian Sansteel, where it operated safely and efficiently. The technology is domestically original, with 3 invention patents and 5 utility model patents. Performance features: 1. The device utilizes an innovative combination of three technologies: seamless alloy pipes, nano-coating, and self-cleaning materials ； 2. The inner wall used for heat exchange is of monolithic design; it is made from a high-temperature resistant, wear-resistant, and corrosion-resistant alloy, featuring high strength, being seamless, and capable of withstanding high temperatures. This design prevents water vapor from entering the carbonization chamber, while the rising pipes have leak-proof properties ； 3. The inner wall is equipped with a nanocoating to meet the demands of harsh operating conditions such as high temperature fluctuations in raw gas and corrosive media ； 4. The inner lining of the rising tube is made of high-temperature and corrosion-resistant materials, and is further equipped with nanomaterials and self-cleaning materials; its inner surface is smooth, making it difficult for graphite and tar deposits to form there ； 5. A special heat exchange structure and automatic control technology are employed to maximize the heat exchange efficiency, while simultaneously controlling the temperature difference between the inlet and outlet of the rising pipe, thereby ensuring the safe and economical operation of the system. Benefit analysis 1: Reduction in energy consumption in the coking process: Energy consumption per ton of coke is reduced by 10 Kg of standard coal ； 2. Direct economic benefits (1.1 million tons of 6.0-meter coke ovens): It is possible to produce 143,000 tons of steam at 0.6 MPa per year; at a market price of 120 yuan per ton, the annual economic benefit amounts to 17.16 million yuan. After accounting for the costs associated with energy and other resources, the investment can be recouped in about 2 years ； 3. Social benefits: Cost savings amount to 13,100 tons per year, with a reduction in C2O3 emissions of 39,000 tons per year; at the same time, it reduces the radiant heat from heating pipes, thereby improving the working conditions for employees. Technical consultation: Qiu Yunbo 13672022822