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Record of Technical Research Efforts by Lunan Chemical’s Acetate Division / Author/Source: Lunan Chemical / Date: 2021-12-17 / Clicks: 8. Two projects carried out by the Acetate Division – “Research and Application of Key Technologies for Million-Ton Acetic Acid Production Facilities” and “Research and Application of Technologies for Optimizing the Operation of Acetate Production Facilities and Increasing Their Capacity” – won the second prize for scientific and technological progress awarded by the Energy Group. Technology reaches new heights. On June 23, 2005, Lunan Chemical’s first 200,000 tons per year acetic acid production facility was successfully commissioned, producing qualified acetic acid products from the very first batch, thereby breaking the monopoly of multinational companies in the field of acetic acid production technology. After more than a year of data analysis and verification, assimilation of knowledge, and continuous exploration of the system, all members of the technical research team carried out over 120 technological modifications. This effort resulted in the development of the first domestically developed acetic acid production technology with independent intellectual property rights in the industry. It has facilitated the widespread adoption of China’s own acetic acid synthesis technology, thus opening up a new path for the nation’s industrial development! On this basis, the second-phase plant with an annual production capacity of 300,000 tons of acetic acid was completed and put into operation in October 2008. To unlock the potential of the facility and increase its acetic acid capacity equivalent, between 2011 and 2015, the research team carried out three rounds of technical efforts to boost the facility’s production capacity. The production capacity of the two sets of equipment has been increased from 500,000 tons per year as originally designed to 800,000 tons per year. At the same time, the problems of high levels of iron ions and propionic acid in the acetic acid product were successfully resolved, marking a significant advancement in acetic acid production technology. This technological achievement has won numerous awards at the ** level as well as at the provincial and ministerial levels. Technological innovation knows no bounds. To further unlock the potential of the equipment, increase production capacity and product quality, and maximize operational efficiency, in 2018, the research team set its goal once again at an annual production volume of 930,000 tons. To ensure the smooth implementation of the project, all members of the task force overcame numerous challenges, including a tight schedule, heavy workload, lengthy bidding processes for special materials and equipment, and great construction difficulties. They worked backward from the deadline, strictly adhered to all timelines, and put in overtime to complete all tasks. During the system startup phase, its performance differed significantly from that before the modification. To ensure the project’s successful commissioning and optimal performance, team members stayed closely attached to the production system, working tirelessly on the production floor for several consecutive days to analyze and identify the causes, as well as adjust the composition of the mother liquor. Through unremitting efforts, by the end of July of the same year, the total production capacity of the acetic acid plant was increased from 800,000 tons per year to 930,000 tons per year. Meanwhile, the quality of acetic acid products has been significantly improved, reaching a leading level in China, thereby enhancing the enterprise’s core competitiveness. In 2019, the research team set its sights on the optimization and upgrading project for the capacity of two acetic acid production units, aiming to increase it to 1 million tons per year. Once the project is approved, the department holds weekly project meetings to discuss every detail of its implementation, arrange tasks appropriately, and strictly monitor the deadlines. Prior to the major overhaul in 2019, all team members worked together to remove the existing special-material heat exchanger for acetic anhydride, conduct a comprehensive inspection of the equipment, and hoist and position the Acetic Acid II unit. They also utilized reclaimed and on-hand materials to prefabricate pipes and prepare pipe ends. During the major renovation, they overcame challenges such as tight deadlines and heavy workloads, worked together at the renovation site, coordinated with the construction workers regarding the project renovation process, carefully verified each component such as pipes and valves, and ensured strict control over the construction quality. All members work overtime every day until after 10 p.m.; only after there are no workers at the construction site do they hold a meeting to review the progress of that day’s work and determine the tasks for the next day before leaving. Upon completion of the project, an implementation plan for increasing the load of the Acetic Acid II unit was prepared promptly, with timelines set for the commissioning of the project’s equipment, the optimization of mother liquor composition, and the increase in system load; the work to raise the system load was carried out in accordance with these timelines. During the period of system load adjustment, system discussion meetings were held every evening at 8 o’clock, led by Li Zhiyuan, who was the company’s chief engineer at the time, and Lu Yiwu, the general manager of the Acetate Division. These meetings took place in the control room of the Acetate Division, where issues within the system and factors that affected its performance were discussed. A series of problems were resolved, including imbalances in the composition of the mother liquor, excessively high liquid levels in the pre-washing tower, frame oscillation, fluctuations in the operation of the regeneration tower, and abnormal operations in the dehydration tower. Through relentless efforts, on May 12, 2019, the production capacity of the Acetic Acid II plant was increased to 600,000 tons per year. Following system optimization, a 72-hour evaluation and acceptance test for the project was conducted from May 14 to 16, and all technical parameters met the design targets set for the project. The daily output of both acetic acid production units increased from 2,400 tons to 3,100 tons, thus successfully achieving the goal of a annual production capacity of one million tons. On December 5, 2019, the China Coal Industry Association organized experts to conduct a technical evaluation of the project focused on the research, development, and application of key technologies for the million-ton acetic acid production facility at Lunan Chemical. The evaluation concluded that the achievements obtained in this area reached an internationally advanced level. On December 16, the acetic acid products were recognized as a “High-Quality Brand in Shandong Province”. Production increased, quality improved, and efficiency rose. The ethyl acetate and butyl acetate production units in the Acetate Division were put into operation in December 2008 and October 2011 respectively; the initial designed capacity for each of these two units was 100,000 tons per year. To maintain the uniqueness and competitiveness of the facilities, since the completion of the project, the division has established a technical research team focused on increasing production capacity. The team has been bold in innovating in key technological areas, optimizing the system’s process flow and operating parameters. Numerous technical upgrades have been carried out on equipment with limited production capacity. Thanks to these optimizations, both facilities now boast a production capacity of 200,000 tons per year, thus achieving the set goals. At the beginning of 2010, members of the task force visited numerous domestic related enterprises and experienced design institutes to collect and organize relevant data and information. Ultimately, they obtained highly valuable data and information, and concluded that the design of the distributors in the product towers and the trays in the recovery towers are the key factors limiting the increase in production capacity. The team members promptly developed a plan for upgrading the equipment and optimized the system; as a result, the production capacity of the ethyl acetate plant increased from 100,000 tons per year as originally designed to 180,000 tons per year. During the subsequent actual operation, in order to further increase production capacity, the team members carried out modifications and upgrades to key equipment such as the product bottom extraction pump, ethanol feed pump, and the heat exchange apparatus located on the side of the product tower. At the same time, due to the increased production capacity, more ethyl propionate accumulated in the reaction vessel, which affected the product quality to a certain extent. To ensure product quality, the team members further optimized the pipelines for extracting the middle-component and light-component fractions. Through these optimizations, the product purity was increased to over 99.9%, with a 100% rate of high-quality products; the main content of ethyl ester exceeded the national high-standard levels and met export-grade requirements. At the same time, the system’s energy consumption was at an advanced level compared to other industries. Over the decade from 2008 to 2018, the team members resolved more than 40 technical barriers that hindered production increases. While maintaining product quality, the production capacity of both units was increased from the originally designed 100,000 tons per year to 200,000 tons per year. According to expert evaluation, this research achievement has reached the international advanced level. Subsequently, the R&D team set its sights on the high-end market. In the second half of 2020, deiodinated acetic acid held a clear price advantage in this high-end market, but the requirements regarding product specifications were extremely strict. To enhance the competitiveness of their products, the R&D team carried out a series of technical efforts, including theoretical analyses, process improvements, and optimization of specifications, and ultimately managed to bring the iodine content of deiodinated acetic acid in line with the requirements of the high-end market, thereby succeeding in entering this sector. At the same time, by working in collaboration with supply and marketing companies, business departments, and quality inspection centers, exchanges regarding product quality and services are carried out, and other high-end end-users are developed. This not only helps to establish a brand image for high-quality products but also creates new sources of growth for the company’s development.