Dongxinyuan’s new technology in hydrogen production from waste gas has passed evaluation

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New technology developed by Dongxinyuan in the field of hydrogen production from waste gas passes evaluation. Author/Source: Collaborative Group on Advanced Processing and Hydrogenation of Coal Tar. Date: 2020-04-20. Clicks: 28. The challenges associated with China’s first oxygen-based hydrogen production system without a shift converter have been successfully overcome. On April 18, the scientific and technological achievement of \"A new green process for hydrogen production from waste gas without conversion, developed independently by Shaanxi Dongxinyuan Chemical Co., Ltd.\", was evaluated in Xi’an by the Shaanxi Petroleum and Chemical Industry Federation. Experts believe that this technology is at the international leading level in the field of hydrogen production from waste gas, and holds great potential for widespread application. Dongxinyuan Company possesses production facilities with capacities of 1.8 million tons per year for lignite carbon, 500,000 tons per year for coal tar hydrogenation, 20,000 tons per year for metallic magnesium, and 2×25 MW for cogeneration; these facilities form a circular economy industrial chain that integrates coke, tar, magnesium, and electricity production. The hydrogen production facility using waste gas is the first of its kind in China to employ pressure swing adsorption technology without the need for a shift converter. Song Ruchang, Secretary of the Party Committee and Chairman of Dongxinyuan Company, explained that in order to address technical challenges such as unstable operation of the hydrogen production units using waste gas, low hydrogen yield, short service life of adsorbents, and waste gas emissions, over the past few years they have relied on their own technical capabilities to carry out continuous research and process improvements, thereby developing a three-stage hydrogen production process that includes gas pretreatment, oxygen-enriched gas utilization for hydrogen production, and PSA vacuum regeneration for purification. The flushing and regeneration process in the purification section was improved to vacuum regeneration, which enhanced the regeneration efficiency of the adsorbent and the hydrogen yield; the hydrogen recovery rate increased from around 65% in the traditional method to over 85%. Meanwhile, addressing the fact that 45% of the gas produced in traditional semi-coke processes is used as fuel for reusing in the furnace, a technology was developed for using gas generated during hydrogen production as a substitute for furnace gas. This approach increased the amount of gas that can be exported from semi-coke production facilities by over 80%, significantly raising the hydrogen output of hydrogen production units; the hydrogen production capacity became three times higher, with a purity of 99.9%, far exceeding the design specifications and fully meeting the requirements of hydrogenation processes ； The desorption gas produced as a by-product of hydrogen extraction from gas is used as fuel, enabling the complete comprehensive utilization of waste gas and driving the green development of the semi-coke industry. The appraisal committee, headed by Li Wenhong, a professor at the School of Chemical Engineering at Northwest University, believes that this technology addresses the common industry problem of low efficiency in utilizing hydrogen from waste gas produced in the coking industry. It develops a new green process for producing hydrogen from such waste gas without the need for conversion processes, overcoming the technical challenges associated with its implementation. Moreover, this process is advanced and rational, results in low hydrogen production costs, and constitutes a complete set of systematic process technologies. The committee recommends accelerating its adoption and promotion within the industry. To date, Dongxinyuan Company’s hydrogen production facility that utilizes raw gas without conversion has been operating stably for over 600 days; its gas processing capacity is 180,000 cubic meters per hour, with an expected capacity of up to 300,000 cubic meters per hour ； Hydrogen production increased from less than 14,000 cubic meters per hour to around 40,000 cubic meters per hour; the daily oil output reached 1,600 tons, resulting in an annual increase in oil production of 224,000 tons and an additional economic value of 1.075 billion yuan. To date, the company has obtained 8 utility model patents in the field of hydrogen production from waste gas, and 1 invention patent application has been filed.