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Achieving Efficient and Clean Utilization of Coal Resources – The Energy-Saving Technology of Direct Connection between Water-Coal Slurry Water Wall and Waste Boiler for Gasification; Author/Source: Sinochem New Network; Date: 2021-04-12; Clicks: 4. To achieve efficient and clean utilization of coal resources, Beijing Qingchuang Jinhua Technology Co., Ltd. developed the energy-saving technology of direct connection between water-coal slurry water wall and waste boiler for gasification (i.e., the Jinhua furnace). This new technology, which converts coal into clean gases of CO and H₂, solves the world-wide challenge of efficiently gasifying complex coal types; it pioneers a new approach to coal gasification upgrades, and for this reason it was recently included in the \"Green Processes in the Petrochemical Industry (2020 Edition)\". Solving the challenges of gasification of coal with \"three highs\" – high sulfur, high ash content, and high ash melting point – is something that the Jinhua furnace was the first to achieve. In the past, due to the lack of efficient and clean large-scale gasification technologies and equipment that could use \"high-sulfur, high-ash, and high-carbon\" coal as raw material, a large amount of coal resources were neglected by the coal gasification market for long periods, or were used for combustion and coking, resulting in significant waste of resources and environmental pollution. Jinhua Furnace innovatively combines water-coal slurry, water-cooled walls, and radiant steam generators, addressing the issue of low thermal efficiency in traditional water-coal slurry gasification furnace systems and endowing \"high-quality\" coal with a new purpose. The Jinhua furnace is able to overcome the limitations of raw materials with high ash melting points because its gasification furnace combustion chamber features a membrane-type water wall. The molten slag particles move to the water-cooled wall where they cool and solidify to form a solid slag layer; when the temperature exceeds the melting point of the coal ash, the surface of this solid slag layer liquefies to form a liquid slag layer. The slag layer with high thermal resistance protects the water wall, allowing the gasification temperature to reach 1700°C. This not only broadens the range of feedstocks that can be used in the gasifier but also eliminates a major obstacle to the clean utilization of \"high-carbon, high-ash, and high-sulfur\" coals. The expanded adaptability to different coal types has also led to an increasing number of industrial application cases for Jinhua furnaces over the years. Over a period of 3 years, 20 coal chemical enterprises at home and abroad have signed contracts for 49 Jinhua furnaces, which are used in various coal chemical applications such as ammonia synthesis, coal-to-methanol production, coal-to-ethylene glycol production, and coal-to-hydrogen production; 10 of these gasification furnaces have already been put into operation. Environmentally friendly and energy-efficient, the Jinhua furnace water-coal slurry gasification technology enables the recovery of the heat contained in the high-temperature syngas through the radiant waste boiler located at the bottom of the combustion chamber; simultaneously, high-quality saturated steam is generated as a by-product. For every 1,000 standard cubic meters of useful gas, 0.65 to 1.1 tons of saturated steam at 10 MPa can be produced as a by-product. Taking the gasification system of a 600,000 tons/year ammonia synthesis plant as an example, without increasing other consumptions, the by-produced high-pressure steam can save approximately 95,000 tons of standard coal per year; at current market prices, this results in an annual economic benefit of around 47.5 million yuan. For example, in the coal-water slurry gasification unit of Jindadi Chemical Co., Ltd., which belongs to Henan Jinshan Group, 1 ton of ammonia can generate 1.4 tons of high-pressure saturated steam as a by-product; this means that per ton of ammonia produced, 0.128 tons of standard coal can be saved, and carbon dioxide emissions can be reduced by 0.36 tons. At the same time, the Jinhua furnace can use high-concentration organic wastewater and organic solid waste to produce gasification feedstock, enabling the economical and efficient simultaneous treatment of organic waste. Jinhua furnaces also have environmentally friendly characteristics. Since the gasification temperature in the combustion chamber can reach 1700°C, the gasification efficiency of the raw material gas is high. The solid residues discharged from the furnace contain low levels of carbon, and the wastewater emitted does not contain hexavalent chromium, tar, or phenols; as a result, waste pollution is minimal and easy to handle. Compared to dry powder gasification waste boilers and refractory brick gasifiers, the Jinhua furnace reduces the boiler drying time, eliminates the coal drying process, and lowers exhaust gas emissions. The development of the Jinhua Furnace 4.0 is in progress. During the 13th Five-Year Plan period, the Jinhua Furnace won various awards, including the Gold Award in the \"Innovation and Entrepreneurship Award・Project Category\" at the National Invention Exhibition in 2017, the Special Prize for Science and Technology from the China Coal Industry Association in 2018, and the Gold Award at the 47th Geneva International Invention Exhibition in 2019. All of this is made possible by the collaborative research and development of the \"Industry-Academia-Research-Application\" alliance. Beijing Qingchuang Jinhua Technology Co., Ltd. is the organizer of the \"industry-university-research-application\" alliance for Jinhua furnaces, as well as the developer of the software related to the technical process packages for these furnaces. It has been responsible for comparing and evaluating different technical solutions, and has worked together with relevant organizations and manufacturing enterprises to develop key equipment such as a new generation of modular process burners, new types of membrane water walls, unique circular single-tube structures, and radial dual-membrane membrane water walls. During the equipment manufacturing, installation, as well as the training of operators, testing, and commissioning of the systems, it has resolved numerous technical issues, thereby contributing to the development of Jinhua furnace technology. “During the 14th Five-Year Plan period, Jinhua Technology will continue to promote the use of Jinhua Furnace 3.0 and develop Jinhua Furnace 4.0, with the goal of creating large-scale gasification furnaces with full heat recovery that can handle 3,000 tons of coal per day.