【Ten Years of Great Progress in Chemical Technology】029-2019: China’s First Facility for Converting Coke Oven Gas into Syngas

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The process in which hydrocarbons react partially with oxygen under high temperature and pressure in the absence of a catalyst to produce syngas (CO+H2) is known as non-catalytic partial oxidation. This process was developed in the early 1950s and is primarily used to produce syngas from residue oil or natural gas as raw materials. The development of this technology has been very slow; firstly, it was constrained by the technical and equipment limitations of that era. Issues such as the short lifespan of key equipment in this process (nozzles, refractory bricks in conversion furnaces, waste heat recovery devices, etc.) and the high amount of carbon black present in the syngas hindered the practical application of non-catalytic partial oxidation technology ； Secondly, the energy consumption in the oxygen production (air separation) process at that time was high, making it impossible for it to compete economically with the process of producing syngas via natural gas steam reforming. However, uncatalyzed partial oxidation also has significant advantages: first, no catalyst is required, so there is no need for pretreatment of the feedstock; the feedstock can be diverse, including various carbon-containing organic substances in gaseous or liquid form, such as waste liquids and waste gases ； Secondly, the H2/CO ratio of the syngas after conversion is close to 2:1, which is highly suitable for methanol, ethylene glycol, and F-T synthesis processes; there is no need for a shift unit, **which simplifies the process flow and reduces costs** ； Third, no process steam is required, resulting in a significant reduction in the system’s energy consumption. Starting in the 1980s, this technology once again became a focus of research and development. On May 20, 2019, news came from Ningxia Baofeng Energy Group Co., Ltd. stating that the country’s first synthesis gas production unit that utilizes non-catalytic partial oxidation of coke oven gas, and which features independent intellectual property rights, successfully passed a 72-hour continuous operation test at this company. The capacity of this unit per furnace is 75,000 Nm3/h of coke oven gas, making it the largest coke oven gas conversion unit operating on a per-furnace basis to date. The on-site assessment of this installation was organized by the China Petroleum and Chemical Industry Federation. The assessment panel was headed by Senior Engineer Sun Zhengtai, former vice president of China Tianchen Engineering Corporation; Hu Wensheng, deputy chief engineer of Donghua Engineering Technology Co., Ltd.; and Senior Engineer Zhao Fangping from China National Petroleum Corporation Lanzhou Petrochemical Company served as other members of the assessment panel. The expert group believes that the device for producing syngas through non-catalytic partial oxidation of coke oven gas is safe and reliable, features a high degree of automation, flexible operation control, and excellent environmental performance, thereby enabling the device to operate in a stable, efficient, and optimal manner. The key equipment has a long service life and high efficiency in hydrocarbon conversion; highly toxic pollutants such as thiols and other organic sulfur compounds, phenols, benzene, and naphthalene in coke oven gas are decomposed at high temperatures within the conversion furnace, resulting in excellent environmental performance. During the evaluation period, the expert team listened to reports on the construction and operation of the demonstration unit as well as the preparations for the evaluation; they discussed and checked the accuracy and reliability of the methods used for measurement, sampling, and calculation of process parameters; they conducted a thorough inspection of the on-site operation of the demonstration unit; they reviewed original records of starting up and shutting down the gasifier, along with other operational data; and they inspected the control room, analysis room, and sites where sampling was carried out. It is reported that the technology used in this device for producing syngas through the non-catalytic partial oxidation of coke oven gas was developed by East China University of Science and Technology based on the technology for non-catalytic partial oxidation of natural gas. Subsequently, East China University of Science and Technology developed long-life burners, non-catalytic conversion furnaces, high-efficiency waste heat recovery boilers and waste heat recovery systems, syngas washing systems, etc., resulting in a series of patented technologies and proprietary technologies. This set of technologies features clean and efficient operation, a simple process flow, and low investment costs. By utilizing this complete set of process technologies, Baofeng Energy constructed the largest single-series syngas production facility using non-catalytic partial oxidation of coke oven gas, with a capacity of 75,000 Nm3/h, in Lingwu City, Ningxia. Construction of the facility began in August 2011, and it was put into operation in May 2014, operating stably to this day with safe, stable, long-term, full-load, and high-quality performance. It is reported that China has approximately 90 billion cubic meters of coke oven gas available for use each year. Converting this coke oven gas into syngas (CO+H2) for the production of major chemicals such as methanol, ethylene glycol, and olefins is of great significance for achieving efficient and clean utilization of coal, enhancing the competitiveness of the coke industry, and promoting the sustainable and healthy development of the coal chemical industry. Traditional steam conversion and pure oxygen catalytic conversion methods involve complex desulfurization processes prior to conversion, which generate secondary pollution; there is an urgent need to develop new, clean, and efficient conversion technologies for coke oven gas.