Approaches to technological transformation in the medium-nitrogen industry

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Approaches to technological transformation in the medium-nitrogen industry: Medium-sized nitrogen fertilizer plants are the backbone of China’s nitrogen fertilizer industry. They not only supply a large amount of fertilizers and chemical raw materials for industrial and agricultural production in the country, but also provide technical and managerial expertise for the development of China’s chemical industry, particularly its nitrogen fertilizer sector. Moreover, they have trained and supplied a large number of professionals, making significant contributions to the development of the national economy. In 1997, the synthetic ammonia production capacity of China’s medium-nitrogen fertilizer industry was 6 million tons, accounting for about 18% of the country’s total capacity, while the urea production capacity was 5.39 million tons, representing 24% of the national total capacity. Including the plants that have developed from small nitrogen fertilizer producers in recent years and have reached a medium scale, there are approximately 100 medium-sized nitrogen fertilizer plants across the country. Their total synthetic ammonia production capacity is around 10 million tons per year, accounting for 26% of the country’s total synthetic ammonia production capacity. The urea production capacity is also around 10 million tons per year, accounting for about 40% of the national total. It is clear that medium-sized nitrogen fertilizer plants constitute the main force in China’s nitrogen fertilizer industry. Most of the medium-sized nitrogen fertilizer plants in our country were built in the 1950s and 1960s. The ammonia synthesis units in medium-sized nitrogen fertilizer plants that use coal as raw material primarily employ process technologies developed in China, such as atmospheric-pressure fixed-bed gasification, rubber-coating desulfurization, thermal potassium-alkali decarburization, reciprocating compression, and high-pressure synthesis ； Urea production primarily employs a fully closed-loop aqueous solution process. The ammonia synthesis process using oil as a raw material was also developed in China. Only some plants that use gas as a raw material adopt imported technology. Overall, the production technologies for synthetic ammonia and urea in our country are relatively backward, especially in those factories that use coal and coke as raw materials. Built in the 1950s and 1960s, some of these factories have inherent shortcomings due to their outdated equipment ； It has high energy consumption, has been in operation for many years, and insufficient efforts have been made for renovation. Moreover, the vast majority of existing medium-nitrogen enterprises have relatively small-scale single-series plants (typically 60,000–80,000 tons per year for ammonia synthesis, and 130,000 tons per year for urea); they have great potential in terms of utility facilities and a large workforce, but their competitiveness is low and their ability to withstand risks is weak ； There are also factories whose emissions of waste water, waste gas, and solid waste exceed the **standards, and they urgently need to be upgraded. “During the Eighth and Ninth Five-Year Plans, although some funds were invested in technical upgrades for medium-duty nitrogen fertilizers (such as using loans from the ADB and World Bank to install 12 new sets of 8–131 units in 12 factories, and technical upgrades in more than 20 other factories mainly involved increasing synthetic ammonia production by 20,000–30,000 tons per year and urea production by 30,000–50,000 tons per year), the scale of these upgrades was not sufficient. Under the new circumstances of fierce international and domestic competition, it is imperative to make use of the new technologies developed in recent years to intensify the technological upgrades of medium-nitrogen fertilizer production processes on the existing basis, further expand the scale of these facilities, reduce consumption and costs, narrow the gap with foreign as well as domestic large-scale nitrogen fertilizer manufacturers, and enhance competitiveness. How exactly should it be transformed? Taking everyone's opinions into account, I would like to put forward some ideas on this matter. I. Technical progress must be emphasized. The majority of medium-nitrogen fertilizer manufacturers use domestic process technologies and equipment, and their technological upgrades also rely heavily on new processes and technologies developed by domestic research institutions, design firms, and universities. 1. Transformation of ammonia synthesis process technology: (1) Gas production – The gas generation furnace is equipped with a new type of furnace bottom and grates, and the gas production process is controlled by microcomputers to enable optimized operation ； Superheated steam is used for gas production to increase the steam pressure in the gas generation boiler; furthermore, the gas generation fans are modified to enhance the blowing strength, thereby increasing the gas output per furnace. (2) Spray regeneration technology and new types of fillers are employed for desulfurization to improve production capacity and desulfurization efficiency. (3) The transformation involves upgrading the existing equipment using full low-temperature conversion technology, along with the use of new catalysts. (4) Enterprises using phenol-based decarburization technology for decarburization can be upgraded by employing technologies such as double-tower pressure swing regeneration, sterically hindered amines, and steam-jet flashing ； Companies that use physical absorption technologies can undergo upgrades by adopting low-energy carbon removal technologies such as NHD ； The decarburized rich liquid uses a hydraulic turbine to recover energy. (5) The refined copper washing process has been technically upgraded using new packing and new tray types, while methanation employs a new catalyst. (6) The synthesis process is modified by using new types of internal components, such as the IIIJ-99 model from Hunan Anchun Company or the Nanhua NC-1200 shaft radial synthesis internal components, with a waste heat recovery unit placed in the middle. (7) Compression: The compressor uses a chamber tank, additional cylinders, and improved gas valves and packing to increase the air delivery volume, prevent leaks, and extend the operational cycle. (8) Hydrogen recovery can be upgraded using technologies such as membrane separation or pressure swing adsorption as needed. 2. Transformation of urea process technology: Pre-separation and pre-distillation processes should be adopted ； Install an external cooler for the absorption tower to increase absorption capacity ； Modify a first-stage evaporation heater and a second-stage evaporation heater ； Ammonia pumps, methamine pumps, etc. are modified to use variable frequency speed control as appropriate, along with upgrades and renovations ； A new deep hydrolysis system has been added to recover the condensate from the urea production process ； The granulation tower uses a new type of nozzle. In terms of automatic control, the DES system should be used for optimized control. In terms of utility systems, new technologies such as advanced cross-flow cooling towers and new types of fillers should be adopted to upgrade the cooling water system ； The boiler utilizes circulating fluidized bed technology, incorporates gas generation furnace slag in its fuel mix, employs cogeneration, and achieves multi-level energy utilization. II. Economic efficiency must be given top priority. Through the weak performance of the fertilizer market in recent years, we have come to fully realize that economic efficiency is the foundation upon which a company can thrive. For any technology, process, or equipment, it is necessary to thoroughly examine and evaluate the costs and benefits, as well as carefully calculate the economic returns. Improving economic efficiency is the starting point and goal of all our work (including technological upgrades and enterprise management, etc.); without this, everything else is meaningless. Medium-nitrogen transformation cannot rely solely on adding equipment to increase capacity. To improve technical standards, it is necessary to upgrade the \"bottleneck\" components in the equipment, tap into potential, and aim for high output with minimal input in order to achieve optimal economic benefits. III. By combining capacity expansion and renovation with the pursuit of serialization and scale, it is possible to achieve larger production scales. At present, the ammonia synthesis units in medium-sized nitrogen fertilizer plants across the country have mostly reached a capacity of 80,000 tons per year, which was considered an economic scale during the \"Eighth Five-Year Plan\" period. Anyang Fertilizer Plant took bold steps to expand the capacity of its existing systems to 120,000 tons per year by utilizing old equipment along with new technologies. This is an experience worth promoting and emulating by other factories. In 1996, the Ministry of Chemical Industry held a national seminar on the development of the medium-nitrogen fertilizer industry at Anyang Fertilizer Plant; the plant had already proposed this idea, but it was not fully accepted by everyone. Two years of practical experience have shown that this idea has been put into practice, yielding good economic benefits: the energy consumption per ton of ammonia can be reduced by 6.3–7.5 GJ, and the production cost of urea can be lowered by approximately 20%. Although the processes and equipment used in medium-nitrogen fertilizer production facilities in our country vary from plant to plant, they are generally similar, and reforms can be carried out by referring to the model of Anyang Fertilizer Plant. If 20 of the fertilizer production plants across the country that use coal and coke as raw materials are upgraded first, the production capacity of synthetic ammonia could increase from 80,000 tons per year to 120,000 tons per year, while the production capacity of urea could rise from 120,000 tons per year to 200,000 tons per year. In total, this would result in an increase of 800,000 tons per year in synthetic ammonia production capacity and 1.4 million tons per year in urea production capacity – roughly equivalent to adding three fertilizer plants with a production capacity of 300,000 tons per year each. Moreover, the investment required would be much less compared to building new plants. This is a good approach for the technological upgrading of medium-nitrogen fertilizers in our country. In recent years, in the competition of the market economy, a number of small fertilizer companies have stood out, with their scale reaching that of medium-sized nitrogen fertilizers. How to further transform these small-scale fertilizers requires careful consideration of solutions, with an effort to achieve a scale that is economically viable. Regarding the renovation of raw material supply routes, conditions vary from factory to factory, so thorough analysis must be conducted based on each facility’s specific characteristics; approaches should be tailored to local conditions rather than forcing uniformity. IV. Emphasize product structure adjustment and the development of diversified operations. The majority of medium-nitrogen fertilizer manufacturers in our country are old plants that have been in operation for decades; many of these plants produce several or even dozens of different products, with few having a single type of product. This provides a solid foundation for adjusting the product structure and pursuing diversified operations. The Zijiang Fertilizer Factory does a very good job in this regard. The factory not only produces blended fertilizers for agricultural use but also develops a variety of fine chemical products. In some factories, the range of nitrogen fertilizer products is relatively limited, which makes them vulnerable to market fluctuations. Even if they produce a few types of products, these do not constitute a significant presence in the market. In future technological upgrades, it is essential to focus on developing a diversified product portfolio rather than relying on just one type of product. It is necessary to combine the use of fertilizers with chemical products, pursuing a path that emphasizes fertilizers while engaging in diversified operations. However, careful consideration is needed when determining the product plan. Two issues need to be paid attention to: one is the market ； The second is the source of technology. Otherwise, it will become a burden. V. Possessing strong innovation and development capabilities – Many medium-sized nitrogen fertilizer plants have already achieved significant economic benefits in this regard. Some factories use new processes and technologies from universities, research institutions, and other factories to upgrade their own technology. In the future, the renovation of the medium-nitrogen fertilizer plant should also strengthen its ties with these departments. It is also possible to introduce some foreign technologies to \"use others’ strengths to make up for one’s own weaknesses.\" At the same time, it is also necessary to improve one’s own ability to innovate and develop, make small improvements and reforms, and increase investment in this area. At present, we are not using new technologies enough in the production of medium-nitrogen fertilizers; we lack boldness in this regard, and it is necessary to change our mindset. The 21st century is an era of the knowledge economy; those who possess new technologies will take the initiative and gain an advantage in market competition, thereby occupying a strategic position in the market economy. VI. Strengthen oversight and regulation to maintain a fair competitive environment; I am referring here to the entire nitrogen fertilizer industry. In 1994 and 1995, the domestic fertilizer market was booming, and a large number of new production facilities were set up across various regions and factories; **a number of projects were also approved, which led to a rapid increase in nitrogen fertilizer production capacity. Coupled with **the large-scale import of fertilizers, this situation resulted in an oversupply of fertilizers in the domestic market. It is necessary to summarize experience and draw lessons, strengthen macro-control over the fertilizer market, and control fertilizer imports. It is necessary to control those projects that only improve efficiency through expansion. Recently, **with the reform of government agencies, industry regulation has weakened, and the industry has faced new challenges such as insufficient working capital, mutual debts among enterprises, and disorderly market competition;** the competent authorities are not very clear about these issues. It is recommended to **strengthen industry regulation and maintain a fair competitive environment**. It is hoped that the relevant industry management department will send investigation teams to the enterprises to conduct in-depth research and help them overcome their difficulties. Furthermore, industry statistics are inaccurate, with some figures being inflated, resulting in a lack of reliable basis for macro-level decision-making. Fertilizer companies are very eager to **pass the Fertilizer Law as soon as possible in order to protect their interests, and so on. These are all areas of industry regulation that need to be strengthened. VII. Appropriate preferential policies should be provided for the transformation of nitrogen fertilizers. Fertilizers are consumer goods that are crucial to the national economy and people’s livelihoods, and solving the fertilizer issue can only be achieved through domestic efforts. Our country is a major agricultural nation, and the international fertilizer market is directly influenced by our country’s demand for fertilizers. Over-reliance on imported fertilizers will inevitably lead to an increase in the prices of fertilizers in the international market. There are lessons from history on this. Therefore, domestic production of fertilizers should not be abandoned due to poor efficiency. **Appropriate preferential policies should be provided to encourage fertilizer production. Specifically, the following suggestions are put forward: (1) Increase lending support; for the projects under the \"8th Five-Year Plan\" and \"9th Five-Year Plan\", loans to **and local authorities should be provided in a timely manner so that these projects can be completed as soon as possible, without any further delays. Loan interest rates should be appropriately favorable. (2) Duties and value-added tax should be exempted for the key equipment imported. (3) Existing medium-nitrogen fertilizer enterprises should be granted the same preferential policies as small fertilizer manufacturers in terms of raw materials, power supply, transportation, taxation, etc., to ensure fair competition. (4) Preferential policies should be granted for bank loan guarantees and fertilizer technology upgrade projects (such as corporate self-guarantees). (5) Continue to maintain the **existing system of buffer funds for chemical fertilizers.