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The Extended MCR Integrated System Overturns Traditional Approaches – Author/Source: Sinochem New Network; Date: June 28, 2019; Clicks: 6. A Major Technical Breakthrough in the Harmless Treatment of Hazardous Waste from Coal Chemical Industries. On June 24, the technical team at Yanchang Petroleum’s Hydrocarbon Research Center unveiled its significant scientific achievement: the multi-functional heat recovery and comprehensive utilization of waste brine (MCR) integrated system. Compared with traditional process technologies, this integrated system represents a revolutionary innovation; it achieves a perfect integration within a single system of the efficient recovery of the sensible heat from crude syngas, syngas purification, the harmless treatment and resource utilization of high-concentration waste brine from coal chemical processes, as well as hazardous waste salts. It is capable of converting these hazardous waste salts into silico-aluminosilicate glassy minerals that are harmless to the environment and pose no leaching risk in open environmental systems. This system addresses the current bottlenecks in China’s coal chemical industry, such as the low utilization rate of the sensible heat in syngas and the high environmental risks associated with the conventional treatment of solid hazardous waste salts. Li Dapeng, a leading expert at Yanchang Petroleum’s coal chemical industry, explained that compared with conventional quenching processes and waste boiler processes, the MCR integrated system offers significant technical advantages: it eliminates the need for complex carbon scrubbing towers that are part of conventional processes, as well as systems for the concentration, evaporation, and crystallization of black liquor, gray liquor, and waste brine. This results in a shorter process flow, higher degree of integration, lower energy consumption, and a markedly improved cost-efficiency. The utilization efficiency of the sensible heat in syngas and slag increases from around 60% at present to about 90%. The internal component structure of this system is simple, making it easy to operate and maintain; at the same time, it generates high-quality superheated steam as well as steam for shift reaction processes, thereby overcoming the problem associated with conventional waste boilers, which require additional backup boilers and thus result in higher investment costs. It achieves efficient solidification of heavy metals and soluble components in mixed salts through high-rate inert particle circulation, system self-heating, and synchronized supply of materials, thereby reducing the operational costs associated with the treatment of solid hazardous waste derived from mixed salts as well as waste brine. It employs dry ash discharge, so no black water or gray water is generated within the system, and no hazardous solid waste in the form of mixed salts is discharged outside the system; this approach addresses the high costs involved in treating waste brine as well as the potential environmental risks posed by hazardous mixed salt waste. In addition, the MCR integrated system has achieved collaborative innovation in multiple technology integrations and the development of key core equipment regarding the efficient utilization of the sensible heat in syngas, the treatment of mixed salt solid waste, and CO2 emission reduction. It has also developed a series of patented equipment and processes with entirely independent intellectual property rights; to date, more than a dozen patents related to these technologies have been applied for or granted. It is understood that fluidized-bed sensible heat recovery systems designed using a similar mechanism have been applied in Kemper’s IGCC project in the United States as well as in a 100-ton/day dual-fluidized-bed gasification industrial test facility, where they have operated continuously and stably over long periods of time. With the use of MCR integrated systems and one-time-only equipment, the investment can be recovered within less than a year, resulting in good economic and environmental benefits. Li Dapeng pointed out that according to authoritative official data, by 2020, the coal chemical industry in China would consume 300 million tons of coal per year, resulting in over millions of tons of miscellaneous salts each year. By using an MCR integrated system, it is possible to produce approximately 165 million tons of high-quality superheated steam per year. It can also handle about 350 million tons of coal chemical wastewater, including highly concentrated waste brine. This approach reduces the costs associated with the treatment of highly concentrated waste brine and various salt-based solid wastes by around 12.6 billion yuan, while generating additional economic benefits of over 29 billion yuan for the entire industry. Thus, it holds extremely broad prospects for market application.