Thread Content
In early December, the project on the development and application of a complete set of technologies for coal gasification using pulverized coal at Baling Petrochemical won the Third Hunan Provincial Workers’ Science and Technology Innovation Award. For the first time in the industry, this technology established the quality standards for coal used in Shell’s powder gasification process as well as the criteria for purchasing raw coal. It introduced the concept of using multi-component blending processes to adjust the key properties of the coal fed into the furnace, and developed a two (or multiple) component blending coal process that holds independent intellectual property rights; this has resulted in cost savings of over 60 million yuan per year. Currently, this technology has been applied in similar facilities across China, such as Sinopec Hubei Fertilizer Plant and China National Engineering Corporation. The pulverized coal gasification unit at Yueyang Sinopec Shell Gasification Company, which is operated jointly by Sinopec and Shell, is a key facility in the renovation project aimed at providing raw materials for hydrogen production at Baling Petrochemical; it utilizes technology supplied by Shell. From its commissioning at the end of 2006 through the trial operation period in 2010, the plant experienced frequent shutdowns due to the complex composition of the feed coal, poor adaptability of the gasification furnace, and frequent clogging of the slag discharge system. These issues not only resulted in direct losses of hundreds of thousands of yuan each time the plant stopped operating, but also severely disrupted the normal production of downstream chemical plants. To address the frequent slag clogging issue in the gasifier and ensure long-term operation of the facility, Baling Petrochemical and Yueyang Sinopec Shell Gasification Company organized professional technical personnel to form a task force for research and solution development. Through investigations into the raw coal resources in surrounding provinces and cities, as well as users of Shell-type pulverized coal gasifiers of the same type, the research team determined that the ash composition of the raw coal is a key factor affecting the stable operation of gasification units. Feng Zhengkun, the leader of the research team, explained that Baling Petrochemical analyzed the composition of coal from the design stage onward, and established a quality database for raw coal resources ； The relationship with different coal types was studied based on the design concept of Shell gasifier’s liquid slag discharge process and the principle of using slag to counteract slag ； Starting with similar Shell powder coal gasifiers in China, the operation of such units and their coal usage characteristics are analyzed and compared ； Study the relationship between the ash composition of the coal fed into the furnace and the fluidity of the slag ； By studying the relationship between the ash composition of the coal fed into the furnace and the operating conditions of gasification, principles for operating the gasification furnace using \"low-sulfur, low-iron-oxide, high-silica-alumina ratio coal under relatively low temperatures and conditions of low slag fluidity\" were established. At the same time, the research team also established quality standards for coal used in powder gasification and procurement standards for raw coal ； The concept of using a multi-component blending process to adjust the key properties of coal fed into the furnace was proposed. Techniques such as multi-component blended coal production processes, key equipment, methods for online monitoring of blending ratios, dynamic economic and technical evaluation models for coal usage, as well as a \"six-point\" control system for the quality of raw coal procurement at various stages (i.e., mining site, dispatch point, port of arrival, storage site, blending site, and coal feeding point) were developed. These measures help ensure high quality in raw coal procurement and proper control of its parameters before it is fed into the furnace, thereby effectively addressing issues such as poor adaptability of the gasification furnace and frequent clogging problems. To date, the research team has completed the development and industrial application of binary and multi-component blended coal technologies, establishing dozens of multi-component formulations and complete blending processes that fully meet the requirements for the long-term operation of the facilities. Feng Zhengkun said that this technology has been successfully applied to the gasification unit at Baling Petrochemical, with the benefits manifesting in the high precision and efficiency of the coal blending unit ； Significantly reduce slag clogging incidents ； Stabilized the operating temperature of the gasifier and increased carbon conversion rate ； Meet the requirements for long-term high-load production of the equipment ； Improved the adaptability of raw coal and stabilized its supply ； Increase the qualified rate of raw coal procurement quality ； Extended the coal replacement cycle ； In eight aspects including reduced effective gas costs, lower coal consumption per ton of ammonia, and lower overall energy consumption per ton of ammonia, the plant’s operating load increased from around 80% to around 95%; the coal consumption for producing effective gas was close to the values specified in the design, and the longest continuous operation period achieved was 225 days. Only the energy and material savings resulting from reduced unplanned shutdowns due to slag blockage, as well as the benefits arising from increased production, were taken into account. From 2011 to 2014, optimized coal usage generated an additional output value of 782 million yuan, with total benefits amounting to 242 million yuan; the average annual benefit was 60.52 million yuan. After the device was capable of operating for long periods under high loads, the amount of acidic gases generated as by-products was significantly reduced; all of these gases could be recovered by the downstream hydrogen sulfide acid production facility. The quantity of hydrogen sulfide as a by-product decreased by 73% compared to before 2010, and the exhaust gases were discharged in compliance with regulatory standards. Technological innovation has enabled coal gasification units to convert coal into gas, thereby promoting safe operation and improved performance. In mid-November, Yueyang Sinopec Shell Coal Gasification Company successfully passed the comprehensive audit conducted by Shell’s Gas-GAME (a global excellence in asset management system), becoming the first company in China and the seventh in the world to achieve Gas-GAME certification.