Four major issues in the park-based development of modern coal chemical industries remain unresolved

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The so-called clustering of coal chemical industries refers to the concentration of multiple coal chemical projects in a certain area, with unified layout and planning. At present, modern coal chemical industry in our country is developing in a park-based manner. In some areas rich in coal, regulations for the development of modern coal chemical industries stipulate that such projects must be located within industrial parks. The author discussed this issue with an associate chief engineer from Datang Energy Chemical Co., Ltd., which was involved throughout the demonstration of coal chemical projects in China. He believes that the ideals for modern coal chemical industrial parks are lofty, but reality is harsh. He is concerned that if the feasibility studies for coal chemical parks are inadequate, the planning is poor and the layout is unsound, if the feasibility assessments of projects within the parks are not handled properly and management is insufficient, then the negative factors associated with coal chemical projects in those parks could combine to have catastrophic consequences. Through discussions with industry experts, the author found that the following four major issues require close attention by coal chemical parks and coal chemical enterprises during planning and construction. The first is the transportation problem. As the name implies, coal chemical industry uses coal as a raw material to convert it into fuels such as oil and gas, or into chemical products such as alcohols, ethers, and hydrocarbons. One of the characteristics of coal chemical projects is the extremely large amount of coal used. For example, in a coal-to-natural gas project with an annual production capacity of 4 billion cubic meters that uses low-quality coal as raw material, more than 24 million tons of coal are required per year, which is equivalent to one trainload of coal being used each hour. If a park has projects of this scale equivalent to 5 such projects, it means that 5 trains of coal need to be delivered continuously 24 hours a day. Added to this is the export of products and by-products, resulting in a substantial volume of traffic; therefore, the layout of railways is extremely important. Not only that. The ultimate goal of coal chemical projects is to convert coal into clean energy or chemical products, a process that generates a considerable amount of waste residue. Taking the 4 billion cubic meter coal-to-gas project that uses low-quality coal as raw material as an example, it generates over 3 million tons of ash, slag, and other waste solids each year. To transport this amount of waste, 25 trucks with a carrying capacity of 15 tons each are needed to make continuous deliveries. If a park contains 5 coal chemical projects of similar scale, just the transportation of waste and solid materials would require over 125 20-ton trucks to be operating continuously per hour. Taking into account the transportation of products and by-products, as well as the return of empty vehicles, the number of vehicles moving around the park will be astonishing. When planning the layout of individual projects, more attention is often given to factors within the boundaries of those projects, and compliance with the overall layout of the park is frequently overlooked or downplayed. As a result, it’s hard to avoid situations where the flow of people and goods from various projects does not align with the road layout and directions in the park; this leads to intersections between vehicles and pedestrians, as well as traffic congestion. Such issues pose two major problems: they affect safety and reduce operational efficiency. In severe cases, this can become a critical obstacle for the project, preventing it from operating at full capacity over extended periods of time. However, some parks clearly did not give sufficient consideration to capacity issues during planning. The second is the slag dump issue. While transportation issues within a region can be resolved through hardware improvements such as building more roads, dealing with waste residues in industrial parks poses a major challenge. A coal-to-natural gas project with an annual production capacity of 4 billion cubic meters generates over 3 million tons of ash and slag per year; if five projects of similar scale are combined, they would produce 15 million tons of ash and slag annually. Although some coal chemical projects stated during the feasibility studies that the ash and slag would be utilized for comprehensive applications such as brick manufacturing and cement production, this has proven difficult to achieve in practice. Since some coal chemical industrial parks and projects are located in remote or underdeveloped areas, there is no market for using ash and slag in brick manufacturing, and it may not be economical either. Thus, landfilling became the only option. The author previously inspected a coal chemical project; since the ash could not be reused as planned, within two years – during which time the plant’s production capacity was utilized for less than a quarter of its potential – the landfill built for storing this ash was already almost filled. To continue production, it would be necessary to acquire more land and build larger, additional landfills. This is a huge burden on the project. If this is the case for just one coal chemical project, it’s hard to imagine how many landfills would be needed to meet the demands of multiple such projects in a coal chemical park. This aspect has not been given sufficient consideration in almost all existing coal chemical industrial parks. In the short term, the conflict may not be apparent, but over time, in 3 to 5 years, it will become a very serious issue. Third is the water issue. Coal chemical industry consumes a large amount of water, and water usage has become the biggest problem. Taking the 4 billion tons per year coal-to-natural gas project as an example again, the annual water demand is 22.5 million tons. If a park has 5 projects of similar scale, its annual water consumption can reach hundreds of millions of tons. As is well known, coal-rich areas are mostly located in the western regions, in an opposite distribution to water sources, and these areas suffer from severe water shortages. In some western regions, the main source of water is the Yellow River water. Some localities and enterprises hope to obtain water quotas for coal chemical industries through water rights transfer projects such as sprinkler irrigation and drip irrigation; for example, the total amount of water allocated to coal chemical industries in one particular area alone amounts to 130 million cubic meters. The problem is that it is unlikely that groundwater will be used for the water needs of coal chemical industries; instead, a large amount of surface water from rivers, lakes, and other sources is required. For example, some projects in the western region rely on the Yellow River as their water source. However, the water demand for coal chemical industries does not vary with the seasons, whereas the flow rate of water in the Yellow River is seasonal. What measures can be taken to ensure an adequate supply of water for coal chemical industries in cases of low water levels that lead to interruptions in water flow, or when there are conflicts over water use with communities downstream? During the feasibility study phase of some coal chemical projects, the local authorities promised water quotas and issued relevant documents. However, in some places, in an effort to secure projects, there is a situation where multiple entities claim the same water quotas, which raises doubts about whether these quotas are actually allocated properly. Fourth is the pollution issue. It is undeniable that coal chemical projects present relatively serious pollution problems, with large amounts of wastewater, waste gas, and waste residue being emitted, which has led to resistance from local residents and skepticism from various sectors of society. In some areas, pollution has already become a serious problem even with just one coal chemical project; after the establishment of industrial parks, pollution emissions increase dramatically, making the pollution issue even more severe. In particular, the impact on the local microenvironment cannot be ignored. Take wastewater treatment as an example: with current wastewater treatment technologies, it is very difficult to achieve zero discharge of wastewater from modern coal chemical industries. Almost all projects rely on inadequate \"evaporation ponds\" or \"temporary storage tanks\" to hold this highly saline wastewater with complex composition that is difficult to treat. In the western regions, the evaporation rate is not sufficient for complete evaporation; as a result, what should be \"temporarily stored\" ends up being \"permanently stored\", making wastewater treatment one of the most troublesome issues in the coal chemical industry. Some coal chemical projects have seen their production hindered by wastewater issues. To the best of the author’s knowledge, there is currently no fundamental solution for wastewater treatment in coal chemical parks, and the difficulty of treatment increases further when the wastewater from multiple projects is combined. The same is true for wastewater; the pollution problems related to exhaust gases and solid waste are also extremely serious and difficult to address. Especially exhaust gases; the cumulative effect of emissions from various sources leads to increased localized pollution. If the pollution problem is not resolved fundamentally, it will be difficult to ensure the safety of coal chemical projects and their surrounding environment. It is easy to imagine what kind of living conditions the residents and enterprise workers living in this area will face. There are far more issues that need to be addressed in the development of modern coal chemical industrial parks, such as safety concerns. The author would like to remind that when planning and designing coal chemical industrial parks, it is essential to take the aforementioned issues fully into consideration and find practical solutions; otherwise, it will be too late to think of anything once the problems arise.