The key to coal chemical industry lies in addressing the issue of \"coal at the beginning and water at the end\"”

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Source: China Chemical Industry News. A common phrase in the coal chemical industry is “coal at the beginning and water treatment at the end,” referring to the gasification technology and water treatment technology that constitute the ‘beginning’ and ‘end’ of modern coal chemical projects; these are key factors that determine whether such projects can be carried out successfully. As the author understands it, among the various coal chemical projects that have been built in China, many have encountered problems related to the handling of coal at the beginning of the production process and water at the end, which has prevented them from operating continuously and stably after completion, leading to operational difficulties and putting them in a difficult situation. Companies undertaking coal chemical projects need to pay close attention to this issue. Firstly, the coal price determines how well coal chemical projects can perform. As the name implies, coal chemical industry naturally uses coal as its raw material; it relies on coal for its operations. Gasification technology is the key equipment in this industry, with the gasifier acting like a person’s mouth and stomach. However, if the gasifier for a coal chemical project is not chosen appropriately, and the gasifier is not compatible with the coal used, the project will not be able to function properly and will suffer from inefficiencies; such a coal chemical project will ultimately find it difficult to operate stably. Today, there are many different types of gasification furnaces developed both domestically and internationally, and each party claims that its own furnace is the best. However, as the author understands it, each type of gasifier has its own characteristics, as well as its own advantages and disadvantages. The most fundamental point is that each gasifier is suited to a certain type of coal; if the coal type does not match the gasifier, then no matter how good the gasifier may be, it is useless. 　 At present, among the various problems existing in the coal chemical projects already built in our country, the issues related to gasifiers are the most common and have the most serious consequences. For example, a domestic coal chemical project uses gasifiers from a well-known foreign brand. Although these gasifiers have good gasification performance, they are very demanding when it comes to the feedstock – they can only process lump coal that meets specific standards. The production of such lump coal generates large amounts of fine coal, and dealing with this fine coal is quite difficult. Therefore, the cost of feeding coal into this type of gasifier is very high, and in some areas it is simply not possible to meet the project’s coal supply needs. In fact, some companies have not attached sufficient importance to the selection of gasification furnaces; they have not made a scientific and careful choice regarding the combination of furnace and coal. As a result, after the projects are completed, the gasification furnaces are unable to operate at full capacity in a continuous and stable manner, which affects the economic viability of the projects. Secondly, the \"water tail\" factor is related to the environmental protection quality of coal chemical projects. During the gasification process of coal chemical projects, in addition to consuming coal, they also need water – and this is the fundamental reason why coal chemicals rely on water resources. As is well known in the industry, not all of the water used in coal chemical projects can be involved in the gasification process of coal; a considerable amount of wastewater must be discharged, which raises the issue of wastewater treatment at the end of this process. At present, one of the prerequisites for environmental impact assessment approval of coal chemical projects in our country is achieving \"zero wastewater discharge\"; that is, no matter how much wastewater is generated by the project, it must not be released into the environment. Instead, the project needs to recycle and utilize this wastewater so that it can be fully processed within the project itself. However, due to the highly complex composition of the wastewater generated in coal chemical processing, the technical challenges involved in treating it are great, and the costs are also high. At the current stage, to truly achieve \"zero discharge\" of wastewater in coal chemical projects, the wastewater treatment technologies are not yet sufficient, and the costs associated with wastewater treatment are too high, which places a heavy burden on these enterprises. It is thus evident that describing the \"coal head and water tail\" as the \"two branches of Rendu\" in coal chemical projects is by no means an exaggeration. When enterprises launch coal chemical projects, they must find practical solutions for the issues related to coal processing at the beginning and water treatment at the end of the process. Otherwise, the project would rather not be carried out.