The current status and development prospects of China’s coking industry

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The Current Situation and Development Directions of China’s Coking Industry 1. Introduction China is a major producer of coke in the world, accounting for around 36% of the global coke production, while its coke exports make up more than 50% of the total world coke export volume. China has both modern large-scale coke ovens with carbonization chambers 6 meters high, at an international advanced level from the 1990s, as well as some smaller and medium-sized coke ovens built in the past that have a lower level of equipment. Entering the 21st century, structural adjustment and technological progress remain the key themes in the development of China’s coking industry. 2. Current Status and Development Strategies of Coking Production in China 2.1 Current Status of Coking Production in China (1) China’s coke production and exports Over the past decade or so, China’s total coke production has more than doubled, reaching a record high of 139.02 million tons in 1997. Since 1993, China has ranked first in the world in coke production for consecutive years. China’s coke production over the years is shown in Table 1. China is also a major global exporter of coke. In 2000, China exported 15.2 million tons of coke, accounting for over 60% of the world’s total coke exports of 25.1 million tons. China’s annual coke export volumes are shown in Table 2. (2) Current status of coke ovens: Top-loading coke ovens with heights of 6.0 m, 5.5 m, 5.0 m, 4.3 m, 4.0 m, 3.3 m, 2.8 m, 2.5 m, and 2.0 m, as well as rammed coke ovens with carbonization chamber heights of 4.3 m, 3.8 m, 3.2 m, and 2.5 m respectively. According to preliminary statistics on over 400 coking enterprises in China, there are currently 1,197 coking ovens in operation in the country, with a designed coking capacity of 105.67 million tons. Among them, there are 24 coking plants with a production capacity of over 1 million tons per year; the total production capacity is 42.4 million tons per year, resulting in an average production capacity of 1.77 million tons per year per plant ； There are 21 coking plants with a production capacity of 5–1 million tons per year, resulting in an overall production capacity of 14.13 million tons per year; the average production capacity per plant is 670,000 tons per year. China has nearly 250 coke ovens with a built height of >4 meters and a high level of equipment, boasting a production capacity of around 80 million tons per year. In addition, there are over 60 coke ovens under construction or renovation in our country, which will enable an additional coking capacity of 14.5 million tons per year. In this way, by the later stage of the 15th plan, China’s capacity for producing coke will reach 120 million tons. Many large coke ovens in our country lack computer control systems as well as coal charging and coke discharge dust removal devices; some are even equipped with dry quenching systems. The vast majority of coking plants possess advanced, scientific, and stringent production management systems and methods, and the level of production management in these coking ovens has reached international advanced standards. At the same time, China still has a coking production capacity of over 25 million tons per year that comes from small coke ovens with a carbonization chamber height of less than 4 meters and relatively low equipment standards. Traditional coke ovens mainly include various types of \"improved\" ovens and \"integrated improved\" ovens with structures represented by the 75-type, 89-type, and 96-type; the production of such traditional coke ovens has been explicitly prohibited and banned. As can be seen from Table 1, the share of machine-made coke in China’s total coke production increased from 48.2% in 1995, the lowest level, to 75.7% in 2001. By the end of 2002, the vast majority of earth coke ovens in China would be shut down. (3) Current status of coke quality: In recent years, to meet the requirements of coal injection in blast furnaces and improved smelting processes, the quality of machine-made coke in China has seen significant improvement. The average quality of domestic coke and the general quality of exported coke from 1997 to 2001 are shown in Table 3. 2.2 Development strategies for coking production (1) Adjustment of the coking structure. The basic approach to adjusting the coking structure is, in accordance with the requirements set out in Document No. 367 issued by the three ministries in 1997 and Order No. 14 issued by the Economic and Trade Commission in 1999, to completely eliminate traditional coking methods (including improved coking processes) and their related equipment. Small-scale coke ovens with outdated technology and high pollution levels should be phased out gradually, and new construction of coke ovens with a carbonization chamber height of less than 4 meters should be prevented. While maintaining control over the total amount of coke produced, efforts are encouraged to build large-scale coke ovens and large-scale coke production bases in order to improve the overall equipment level of the coking industry. (2) enlargement of coke ovens: Widening and heightening the carbonization chambers, as well as increasing the amount of coke produced per chamber, is the direction of development for coke ovens. Since the 1980s, many large-volume coke ovens with a chamber height of over 7 meters have been built internationally. In 1993, Germany conducted industrial trials of a single-chamber coke-making system with a chamber height of 10 meters. Ovens with a chamber height of 8.43 meters, designed by experts from the EU for the German company DolysRn Rib 2 p, are currently under construction. At present, the largest coke ovens under production in China are those with a carbonization chamber height of 6 meters. Anshan Jiaonai Design and Research Institute is currently working on developing coke ovens with carbonization chambers 6.5m and 7.0m in height. (3) Ramming coking technology: In the coal used for ramming coking, the proportion of low-cohesiveness, high-volatility coal can reach 70% to 80%, and it is even possible to use 100% low-cohesiveness, high-volatility coal for coking. Among China’s coking coal reserves, bituminous coal and fat coal account for 56% and 13% respectively, and are suitable for compacting coking. Most of the coke ovens in operation in China are small-scale ovens with a carbonization chamber height of <3.8 m. Recently, a ramming coke oven developed and designed in China, with a carbonization chamber 4.3 meters high and 500 mm wide, has been built and put into operation. Thanks to an improved ramming device, its operational efficiency has been greatly enhanced. (4) Dust removal ground stations and on-vehicle coke oven dust control technologies. The main types of coal-loading dust removal systems currently in use in China include non-combustion dry ground station dust removal methods, combustion dry ground station dust removal methods, combustion wet ground station dust removal methods, and combined dry ground station dust removal methods for both coal loading and coke extraction. The main types of coke discharge dust removal systems are dry floor station dust removal and thermal buoyancy hood dust removal. In recent years, the dry dust removal coal loading vehicle developed and designed by Anshan Jiaonai Institute has been put into use at the coking plants of Jinan Iron and Steel Group and Kunming Iron and Steel Group. This vehicle features a dry dust removal system equipped with bag filters mounted on a coal loading vehicle; it offers advantages such as low investment costs and ease of implementation. Its dust collection efficiency is greater than 85%, the dust removal efficiency is greater than 99.5%, and the dust concentration at the flue gas outlet is less than 50 mg/m3, meeting the requirements of **environmental protection regulations. (5) The CDQ 0Q technology can not only recover the sensible heat of red coke and improve coke quality, but also reduce air pollution caused by wet quenching; it is an energy-saving and environmental protection technology for coking that is given priority in development and promotion in China. China currently uses mainly units with a processing capacity of 70–75 t/h, which were imported from Japan and Russia/Ukraine. The direction for China’s development in this field is the enlargement of installations and the localization of equipment. The enlargement of the equipment is aimed at matching the production scale of the coke ovens; one set of C2 treatment equipment of corresponding scale is provided for every 1–2 sets of coke ovens, while a wet quenching device is used as a backup to save on investment. The steam generated by the 0Q unit will be used for power generation, coal humidification, or fed into the production steam network. (6) Coal moisture control (CMC): CMC is a technique that involves removing a portion of the moisture from coking coal before it is loaded into the furnace, in order to maintain a stable moisture level in the coal used for firing. This technology has received widespread attention due to its significant energy savings, environmental benefits, and economic advantages, and it has developed rapidly. In 1996, China’s first set of 0-generation units was put into operation at the Chongqing Iron and Steel Co., Ltd. coking plant; these units used heat transfer via thermal oil, resulting in a relatively complex system and high investment costs. At present, Anshan Jiaonai Institute is developing a CMC system that uses steam as a heat source, featuring a simple process and low investment. In this system, steam is used to exchange heat with coal inside a tubular humidifier, and flue gas is utilized to carry away the moisture released from the coal, thereby maintaining the moisture content of the coal used in the furnace at around 6%. This process can increase the production capacity of coke ovens by 7.7%, reduce the consumption of gas used for heating the ovens by 14%, cut the water usage in the primary coolers by one-third, reduce the amount of residual ammonia water by one-third, and correspondingly reduce the demand for ammonia vapor by one-half. (7) Comprehensive automation of the production process: The automation of coke oven production is an integrated system that includes both production control and management automation. The automation technologies for coke oven production that are currently being promoted in China include computer-controlled and management systems for coke oven heating, systems for the dynamic automatic identification of coke oven numbers and alignment control, comprehensive control systems for gas collector pressure, computer network systems for the production management of coking plants, as well as computer-based systems for automatic temperature measurement and management during coke oven drying. The comprehensive automation system for coke ovens has a modular structure, allowing all functions to be implemented at once or gradually, depending on the conditions of each coking plant and the requirements of the users. (8) Heat-recovery coke ovens: Due to their lower cost, reduced pollution, and better quality of coke, heat-recovery coke ovens are attracting the attention of coke industry professionals around the world. The United States, Germany, Australia, India, Mexico, China, and others are actively developing and building such heat-recovery coke ovens. The heat-recovery coke ovens built by American Sun Company have achieved satisfactory results. The test furnace for a ramming coal-loading heat-recovery coke oven, developed independently in China, has been built and put into operation, and is currently being further improved. This type of coke oven is suitable for use in areas where there are no gas users or where electricity is unavailable. 3. Current Status and Development Directions of Comprehensive Utilization of Coke Oven Gas 3.1 Current Status of Coke Oven Gas Purification At present, there are many purification processes for coke oven gas in use in China, including condensation and blower treatment, desulfurization, denitrification, and debenzeneization; these processes enable the purification of the gas while also recovering chemical products such as tar, sulfur, ammonium sulfate or ammonia water, and crude benzene. Chinese coal gas purification processes generally employ efficient cross-tube primary coolers to cool raw coal gas, while the differences among various coal gas purification technologies lie mainly in the choice of desulfurization and denitrification methods. The main ammonia removal processes include the washing-ammonia-evaporation-concentrated-ammonia process, washing-ammonia-evaporation-ammonia-decomposition process, cold-anhydrous-ammonia process, hot-anhydrous-ammonia process, semi-direct immersion saturator ammonium sulfate process, semi-direct spray saturator ammonium sulfate process, indirect saturator ammonium sulfate process, and acid-washing ammonium sulfate process. The desulfurization processes mainly include wet oxidation processes (such as those using ammonia as a base source, the Hzc method, the MF method, as well as those using sodium as a base source, such as the A method and the P16 method), and wet absorption processes (such as the AS method involving combined ammonia and sulfur washing, the Thiolphane method, and the vacuum carbonate method). China’s gas purification technology has reached international advanced levels. Depending on the gas users, different process flows can be selected to meet their requirements for various gas qualities. China’s gas purification technology has reached international advanced levels. Depending on the gas users, different process flows can be selected to meet their requirements for various gas qualities. Gas desulfurization is a mandatory environmental protection measure that is being promoted in China. The introduced desulfurization methods are only applied in large coking plants due to their complex processes and high costs. The desulfurization processes developed in China, such as the improved Frombach method, HS method, and IF method, are more suitable for China’s national conditions. The improved Ba method and PIS method use sodium as the base source, offering high desulfurization efficiency; the H2S content in the gas after the tower can be reduced to below 20 mg/m3, meeting the standards for city gas. The In)F method for desulfurization is a new desulfurization process that uses In)F as a catalyst and ammonia in coal gas as the alkaline source; the H2S content in the coal gas after passing through the desulfurization tower is less than 200 mg/m3, meeting the quality standards for industrial coal gas in China. 3.2 Current status of comprehensive utilization of coking gas: Based on a coking production of 124.06 million tons in 2001, the annual output of coke oven gas is approximately 53 billion m3. Of this, the approximately 12.8 billion cubic meters of gas generated along with 30 million tons of semi-coke is completely burned during the coking process. The gas produced by coke ovens, after being purified, is used to heat the ovens themselves in part; the remaining gas is utilized to varying degrees. In steel complexes, the vast majority of coke ovens are regenerative type ovens, and they are generally heated using blast furnace gas. The gas produced by these ovens, after purification, is supplied to users in ironmaking, steelmaking, rolling, and other processes. As coking plants that serve as sources of city gas, the vast majority of these cokers are regenerative type cokers; they can be heated using coke oven gas or generator gas. The coke oven gas produced is purified to meet city gas standards before being supplied to urban residential or industrial users. At present, independent coking plants that mainly produce coke, such as many new coking plants built in Shanxi as part of the transition from earth coke to machine-made coke, use the excess gas produced by them for power generation, with the exception of a few plants whose gas is supplied to cities for use in heating or for industrial purposes such as calcining high-alumina vanadinite and metallic magnesium. In China, there are mainly two types of coking plants that generate large amounts of excess coke oven gas: one type are independent coking plants whose primary output is coke, and the coke oven gas produced by these plants cannot be supplied to urban users, nor do they have suitable industrial customers ； Secondly, the coking plants that currently supply city gas to users, such as the Beijing Coking Plant, Tianjin Gas Plant, and Shanghai Coking Plant, no longer have suitable customers for coke oven gas after switching to natural gas to supply city gas users. These excess gases urgently need to find economical, reasonable, and efficient ways for comprehensive utilization. 3.3 Development strategies for the comprehensive utilization of coke oven gas. Coke oven gas contains 55%–60% H2, 23%–27% CH4, and 5%–8% CO, with a low calorific value of 17,900 kJ/m3. It is not only a high-quality gaseous fuel but also an ideal raw material for chemical synthesis. Therefore, the comprehensive development and utilization of coke oven gas should also be considered from the perspectives of fuel and chemical raw materials. (1) Combined industrial users that utilize coal gas: As a clean gaseous fuel, coke oven gas can be used in the production of cement, building materials, and refractory materials, thereby **improving the quality and grade of the products. For example, the coking plant in Shanxi Province uses the coke oven gas it produces to roast high-alumina vanadum earth, and utilizes the waste heat from this roasting process to generate steam for all the steam users in the plant. This not only improves product quality and expands the market, but also enables comprehensive utilization of energy, thereby reducing production costs. (2) Develop chemical synthesis projects using coke oven gas as a raw material. Coke oven gas is an ideal raw material for producing synthetic ammonia. Hydrogen is the direct raw material gas for ammonia synthesis. Coke oven gas contains 55% to 60% hydrogen, while other components such as methane and carbon monoxide can be used to produce pure hydrogen through processes like conversion, reforming, and decarburization; thereafter, hydrogen is combined with nitrogen to produce ammonia. In recent years, with the widespread adoption of pressure swing adsorption hydrogen production technology, investment and electricity consumption for producing synthetic ammonia from coke oven gas have been further reduced. Since its establishment in the 1970s, Shanxi Coking Group has built ammonia synthesis plants using coke oven gas as a feedstock, and has been producing urea. Coke oven gas is also an ideal raw material for synthesizing methanol and dimethyl ether, as it contains the feed gases It, Co, and Cq required for their production. After partial oxidation and steam conversion of coke oven gas, the H/C ratio in the gas is 3.0, which is close to the optimal value for methanol and dimethyl ether synthesis (2.05–2.15). When producing methanol and dimethyl ether from coal and heavy oil, the low carbon-to-hydrogen ratio requires the addition of shift and decarburization units, resulting in a longer process flow and higher investment costs. Methanol is not only an important basic organic chemical raw material, but it can also be added to gasoline for blending or used as a substitute for gasoline as a fuel. Clean fuel vehicles powered by methanol, developed in Shanxi Province, have been successfully put into use. Shanxi Province is establishing a methanol production facility that uses coke oven gas as raw material. Dimethyl ether possesses excellent miscibility; it is soluble in gasoline and water. It can be used as a cleaner alternative to diesel as a fuel for vehicles, as well as a substitute for liquefied gas as a fuel for household use, and its future prospects are generally seen as promising. (3) Coke oven gas for hydrogen production: Coke oven gas is an ideal raw material for hydrogen production; the 55%–60% hydrogen it contains can be used to produce hydrogen with a purity of 99.9% or higher through pressure swing adsorption. Hydrogen is one of the important raw gases used in chemical industry synthesis, and it also serves as a common reducing agent and hydrogenating agent in the chemical industry. In the electronics industry, hydrogen is an important raw material for producing semiconductor materials — silicon. Used in meteorology for sounding balloons. Hydrogen has become one of the important fuels for launch vehicles and spacecraft. Pollution-free, high-efficiency hydrogen fuel cell-powered vehicles that can achieve zero emissions have been put into trial operation, and major automobile companies around the world have successively introduced prototypes of this type of vehicle. The scope of hydrogen energy applications will surely continue to expand in the future. (4) Methanation of coke oven gas for urban gas customers: For independent coking plants that currently supply urban gas customers, once natural gas enters the city, the coke oven gas can also be methaneated to increase its calorific value, after which it can be mixed into the natural gas network to supply urban gas customers. This is the case at the Toshima Plant of Tokyo Gas in Japan. (5) Coking gas power generation: When coking gas has no suitable use elsewhere, it can also be used for power generation. When used in power plant boilers, coke oven gas can achieve a thermal efficiency of 90%; steam generated by these boilers is used for power production, and the steam produced can also be utilized by coking plants. Coke oven gas can also be used directly in gas turbines to generate electricity. The coke oven gas turbine generators developed autonomously in China using aero engines have been successfully applied at the Shaanxi Coking Plant and the Jiu Zhou Mining Bureau Coking Plant. (6) Use of coke oven gas for direct iron reduction: In steel complexes, coke oven gas produced by coking plants, which contains large amounts of H2 and O2, is itself a reducing gas. By feeding this coke oven gas into a thermal cracking furnace and carrying out oxygen-catalyzed cracking several times, a reducing gas with 74% H2 and 25% O2 can be obtained, which can be directly used in gas-based shaft furnaces to produce sponge iron. The combined process of blast furnaces for direct iron reduction and coke ovens that results from this is an improvement in the technological processes associated with blast furnace operations, and it represents the necessary path for steel production to transition toward more streamlined processes. 4. Current Status and Development Directions of Tar Processing 4.1 Current Status of Tar Processing In 2001, China’s production of coal tar was around 4 million tons. Coal tar is composed of a variety of complex mixtures, and more than 500 compounds have been successfully isolated from it to date. Coal tar and its processed products are important basic raw materials in fields such as metallurgy, chemical industry, pharmaceuticals, building materials, transportation, and communications, and they hold broad market prospects both domestically and internationally. China’s coal tar processing industry developed alongside the coking industry, with the tar processing unit generally being constructed as a production workshop within coking plants. At present, there are over 50 enterprises in China that possess coal tar processing facilities, with a total tar processing capacity of approximately 2.7 million tons per year. China’s coal tar processing level still lags behind the world’s advanced levels. As early as the 1960s, foreign countries began to build large-scale tar processing plants; the scale of such processing has reached 1.5 million tons per year, with each processing unit having a capacity of 500,000 tons per year. More than 200 different types of products can be extracted through this process. China’s existing tar processing facilities are mainly located in various coking plants, with each facility having a low processing capacity and a limited range of products. At present, the system that holds a leading position in China is the tar processing unit introduced by Baosteel from Japan in the 1980s; its processing capacity is 260,000 √a, with each unit having a processing capacity of 130,000 tons per year, and it can produce 26 different types of products. The remaining tar processing units located in various coking plants have processing capacities of 250,000 √a for Ansteel, 200,000 tons per year for Wuhan Iron and Steel, and 150,000 √a for Benxi Iron and Steel; the rest have capacities of only 50,000–100,000 tons per year. There are more than 10 different types of products produced. A comparison of the coal tar processing status in China and Germany is shown in Table 4. During the Sixth Five-Year Plan period, our country actively advocated for the centralized processing of coal tar. However, due to various reasons, no large-scale centralized tar processing plants have been built yet. Currently, 4–5 such plants are under construction in places such as Shanghai, Henan, and Shanxi, with capacities ranging from 100,000 to 300,000 tons per year. 4.2 Development strategies for tar processing (1) Develop centralized tar processing; economies of scale, as a general economic principle, also apply to the coal tar processing industry. Due to the special properties of coal tar itself, it is only economically feasible to extract components with a content of less than 1% in coal tar by subjecting it to specialized processing. Where conditions permit, the larger the scale of coal tar processing, the better. Practice in coal tar processing shows that the initial economic scale for tar processing should reach 200,000–250,000 tons per year. Since the 1970s, the tar processing industry in countries around the world has been moving toward centralized processing. Achieving centralized processing of coal tar and the enlargement of individual processing units not only helps to improve the level of process equipment, automatic control, and the utilization rate of waste heat, but also creates the fundamental conditions for the further processing of tar fractions. At the same time, thanks to centralized processing, it is also possible to **reduce the number of scattered processing sites, thereby enabling the implementation of maximum environmental protection measures and minimizing environmental pollution. The conditions for the centralized processing of tar in our country are now basically ready. Options include merging the various coking plants or centralizing the processing, or establishing separate, specialized companies for coal tar products to handle the coal tar from all coking plants on a centralized basis. Coking plants that supply the raw material coal tar can contribute shares based on the amount of tar they provide, and receive dividends from the profits according to that amount. This not only ensures a stable supply of raw tar for the centralized processing plants, but also takes advantage of the benefits of centralized processing to improve product quality and quantity, thereby achieving the best economic outcomes in the fierce market competition. (2) Develop centralized processing of tar fractions. On the basis of centralized tar processing, China should further pursue centralized and in-depth processing of tar fractions; individual tar processing enterprises should avoid attempting to carry out comprehensive, small-scale processing of these fractions. The development approach for the centralized processing of tar fractions should involve several tar processing companies in the same or adjacent areas pooling their respective fractions together for processing. Each company focuses on carrying out advanced processing of one or two types of fractions, thereby making the scale of such advanced processing equivalent to the sum of the scales of all those companies. Each tar processing enterprise can contribute shares based on the amount of distillates provided, and receive dividends from the profits in proportion to that amount. Distillates that are suitable for centralized processing include phenol oil, tea oil, washing oil, crude oil, etc. Achieving further concentrated and in-depth processing of fractions allows for maximizing the concentration of the same compound within those fractions, significantly enhancing the level of processing of the fractions and enabling the production of more high-value, market-competitive products. (3) Selecting a tar processing route suitable for national conditions. Currently, there are mainly two routes for tar processing: one is the route represented by Japan, which aims primarily at producing carbon-based raw materials (products), and the other is the route represented by Germany, which aims primarily at extracting monomer products to the greatest extent possible. When selecting a tar processing route, it is not only constrained by the conditions of metallurgical production but also influenced by the overall situation of the petrochemical industry (from products and scale to processing technologies). The development prospects of the fine chemical industry require that coal tar processing must change its product structure, by isolating valuable products from the several hundred compounds already identified in coal tar, as well as by using derivatives in the processing process. At the same time, to meet the growing demand of the electrode industry for high-quality carbon materials, it is also necessary to develop products such as high-quality carbon graphite materials and carbon fibers using coal tar pitch. Therefore, in the development of the two coal tar processing routes, **both should be taken into account (as in China); the coal tar processing plant built by Shanghai Baosteel is a typical example of coal tar processing in China. 5. Current Status and Development Trends of Crude Benzene Processing 5.1 Current Status of Crude Benzene Processing In 2001, China’s crude benzene production was around 1.1 million tons. Similar to the coal tar processing facilities, China’s crude benzene processing industry has also developed alongside the coking industry. The crude benzene processing unit is generally built as a production workshop within a coking plant. At present, there are over 40 enterprises in China that possess benzene processing facilities, with a processing capacity of approximately 700,000 tons per year. In the early 1950s, countries such as Germany, the United Kingdom, the United States, France, and Japan began to develop centralized processing for crude benzene; the processing capacity of each unit reached 80,000–100,000 tons per year, and catalytic hydrogenation refining was gradually adopted in place of the traditional sulfuric acid washing method. Compared with the world’s advanced levels, the level of crude benzene processing in our country is characterized mainly by low processing capacity per unit facility; the vast majority of benzene purification units still use the acid washing process from the 1950s. At the leading level in the country are the crude benzene hydrogenation refining units introduced from abroad by Baosteel Coking Plant and Shijiazhuang Coking Plant, with each unit having a processing capacity of 50,000 tons per year. The largest scale of crude benzene processing is carried out by Baosteel’s coking plant, which processes 110,000 tons of crude benzene per year; the refining facilities for crude benzene in other coking plants have a processing capacity of only 10,000 to 30,000 tons per year. 5.2 Development strategies for crude benzene processing (1) Develop centralized processing of crude benzene. The purpose of crude benzene processing is to separate high-purity products such as benzene, toluene, and xylene from the crude benzene mixture. Increasing the individual processing capacity of units for the centralized treatment of crude benzene allows for optimal utilization of advanced processing technologies, improves the yield and quality of the products, reduces environmental pollution resulting from decentralized processing, and achieves the best economic and social benefits. The minimum economic scale for benzene refining should be 50,000 t/year. Where conditions permit, the larger the scale of crude benzene processing, the better. The development approach for the centralized processing of crude benzene should involve coking plants located in the same area or adjacent areas pooling their crude benzene for processing. Each company contributes according to the amount of crude benzene it provides, and profits are distributed based on that amount of crude benzene contributed. (2) Select a benzene crude processing technique suitable for the national conditions. The main processes for refining benzene crude are acid washing and hydrogenation. The pickling method is a commonly used process for processing crude benzene in China, offering advantages such as a simple process flow, flexible operation, simple equipment, readily available materials, and the ability to operate at normal temperature and pressure. However, compared to the hydrogenation method, it has fatal drawbacks such as poor product quality, low yield, and poor environmental protection (there are still no effective solutions for dealing with the initial distillate, regenerated residues, and acid tar). The hydrogenation method is a processing technique for crude benzene that is widely used abroad. Its notable advantages include high yields of benzene-based products (8% to 10% higher than those achieved by the acid washing method), high product quality (especially low sulfur content), good environmental protection (virtually no waste residues, liquids, or gases are emitted), and excellent economic benefits. The development direction of crude benzene processing technology in our country should be hydrorefining. At present, our country has the conditions to build a crude benzene hydrogenation and refining unit. Apart from the main equipment and instruments, the rest can be manufactured domestically ； In China, the technology for producing pure hydrogen (99.9%) using pressure swing adsorption with coke oven gas as the hydrogen source is mature ； The Letho process (model t01) hydrogenation units that have been introduced and put into operation in China (Baosteel) and the solvent-based hydrogenation units (Baosteel, Shijiazhuang Coking Plant) provide valuable experience that can serve as a reference for the construction and operation of crude benzene hydrogenation refining units in China. 6 Conclusion As it enters the new century, China faces the arduous task of transforming from a major country in coking production into a powerful force in the coking industry. While replacing traditional coke ovens as well as small and medium-sized mechanized coke ovens with large-scale mechanized ones, upgrading existing coking enterprises using advanced environmental protection, energy-saving, and automation technologies should be the goal that China’s coking industry aims to achieve in the near future of this century.