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There is an unavoidable problem in China’s phosphorus chemical industry: phosphogypsum. The by-products of this phosphate production have accumulated nationwide to over 800 million tons, with an additional 80 million tons added each year; the overall utilization rate has remained below 40% for a long time. The large-scale open-air storage of phosphogypsum poses problems such as land occupation, dust generation, and groundwater contamination from leachate, and is recognized as a \"dead end\" in this industry. Relying on two key technologies—the co-production of sulfuric acid and cement from gypsum, and the chloride process for titanium dioxide production—Shandong Lubei Enterprise Group General Corporation has provided a feasible solution to this “intractable problem”. In the first quarter, Lubei Chemical, the group’s key listed company, achieved a net profit attributable to the parent company of 56.5559 million yuan, a year-on-year increase of 57.07%, thus delivering solid economic results. From “waste residue” to a resource. In the 1980s, while most phosphate and compound fertilizer enterprises were still struggling to find a use for phosphogypsum, Lubei—which had just begun operations on the saline-alkali land along the Bohai Bay—set its sights on solving this problem. “The main component of gypsum is calcium sulfate; is it possible to break it down into sulfur dioxide and calcium oxide? The former can be used to produce sulfuric acid, while the latter can be used in cement production. Could sulfuric acid then be used again in the production of phosphatic ammonium fertilizers? This idea makes sense in principle, but whether it can be implemented on an industrial scale remains uncertain. What followed was a long period of hard work. Phosphogypsum has a high content of free water and large variations in composition, which makes it easy to cause blockages when dried in kilns ； Even a slight change in the atmosphere inside the kiln results in a significant drop in the decomposition rate. From the research efforts during the Sixth Five-Year Plan period to the industrialization efforts during the Seventh Five-Year Plan period, and from further expansion during the Eighth Five-Year Plan period to the development of supporting facilities during the Ninth Five-Year Plan period, northern Shandong managed to transform the process of producing sulfuric acid and cement from gypsum into a full-scale industrial operation. Subsequently, the related technology won the **Second Prize for Scientific and Technological Progress Award and the Silver Award of the China Patent Award. In July 2025, the key technology for wet acid production, developed jointly by Lubei and Keyang Environment, passed the evaluation of scientific and technological achievements organized by the China Petroleum and Chemical Industry Federation. The evaluation panel concluded that this technology introduces a novel “one rotation, one cooling” process, enabling a single-pass conversion rate of sulfur dioxide exceeding 99.3% under conditions of high water vapor partial pressure, thus reaching international advanced levels. Today, a single plant in northern Shandong is capable of producing 400,000 tons of sulfuric acid and 600,000 tons of cement per year through combined production; it also recycles approximately 1 million tons of gypsum waste and 300,000 tons of waste sulfuric acid each year. Industrial by-product gypsum is continuously fed into the rotary kiln, while the resulting sulfuric acid and cement are sold directly in the market. What was once waste has become an important resource in the circular economy chain. Overcoming “tough challenges” If the sulfuric acid production from gypsum resolved a “deadlock” in the phosphate chemical industry, then the breakthrough in the chlorination process for titanium dioxide technology broke another “shackle”. China is the largest producer of titanium dioxide, with an effective production capacity of around 5.7 million tons by 2025, accounting for over 50% of the global total. However, for a long time, the vast majority of domestic enterprises have followed the old path of the sulfuric acid process—a process that is lengthy, energy-intensive, and produces large amounts of waste acid and phosphogypsum as by-products. The chlorination process, which offers advantages such as short processing times, low energy consumption, and high quality, has had its core technologies under foreign control for a long time; moreover, the technical approaches introduced in China earlier also failed to meet the expected results. Northern Shandong is determined to tackle this “tough nut to crack” by establishing a dedicated research institute, starting with the most fundamental oxidation-chlorination coupled reaction. Lubei itself is a hazardous chemicals manufacturing enterprise involving two high-risk processes—oxidation and chlorination. It is extremely difficult to strike a balance between safety and efficiency. After countless trials and repeated attempts, a technological breakthrough was finally achieved, bringing us to a leading level. In 2020, the first large-scale plant was successfully commissioned on its first attempt, making Lubei one of the few domestic enterprises at the time to have mastered the mass-production technology for the chlorination process. Compared to other domestic chlorination plants that often suffer losses due to frequent start-ups and shutdowns, Lubei has achieved continuous and stable operation. Its product specifications are advanced, enabling it to successfully penetrate the high-end coatings and electronics industries. The synergy between the two technologies yields benefits. For northern Shandong, gypsum-based acid production and the chlorination method for titanium dioxide are not two separate technological innovations; rather, they are key components that are interconnected within the same circular economy industry chain. Phosphogypsum produced as a by-product of phosphate production is used to manufacture sulfuric acid and cement; the sulfuric acid is then reused to produce phosphate and titanium dioxide ； The waste acid generated in titanium dioxide production is treated and then used in the production of phosphoric acid and titanium-rich materials. Phosphoric acid, together with the by-product ferrous sulfate, is converted into lithium iron phosphate, a material used in new energy batteries, while the titanium-rich materials are used as raw materials for titanium dioxide production via the chlorination method. It is this circular economy system of \"sulfur-phosphorus-calcium-titanium-lithium\" that has enabled northern Shandong to stabilize its costs despite sharp fluctuations in raw material prices. In the first quarter of this year, affected by geopolitical conflicts, the benchmark price of sulfuric acid rose from around 917 yuan per ton at the beginning of the year to approximately 2,100 yuan per ton in mid-April, representing an increase of nearly 130% ； The benchmark price for sulfur once reached 6,700 yuan per ton, setting a new historical high. Many sulfur-dependent enterprises are experiencing cost reversals and even face the risk of raw material shortages; meanwhile, the cost of producing sulfuric acid from gypsum in northern Shandong is significantly lower than that of the sulfur-based production route. During the same period, overall profits in the titanium dioxide industry declined by over 40%, yet titanium dioxide produced by the chlorination method in Northern Shandong managed to maintain its profitability thanks to high operation rates and superior quality. Lv Tianbao, who rose from a technician to chairman, has been involved in almost all technological challenges. Reflecting on over four decades of experience, he said, \"Traditional industries are not backward industries; rather, they serve as an important foundation for fostering and developing new forms of productive capacity. Our goal is to turn legal boundaries into value creation opportunities.\" ”In recent years, environmental protection policies have become increasingly strict and emission standards more stringent. Lubei Group has turned these strict regulations into a driving force for green development, enabling the circular economy technology system to realize greater value. “Environmental protection is not a source of cost burdens; it is a competitive advantage for industries. ”Lü Tianbao said.