Next-generation phosphorus chemical technology

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The relevant chapter is attached herewith: “Next-generation phosphorus chemical technology” not only eliminates all the major drawbacks of modern phosphorus chemical technology (i.e., traditional phosphorus chemical technology) but also possesses a number of new features that traditional phosphorus chemical technology does not have, namely: (1) it does not produce large quantities of phosphogypsum, which takes up much land and pollutes the environment and water bodies; instead, it generates gypsum powder with high brightness and high purity, or ultra-fine calcium carbonate, as well as slag enriched with dozens of metals and rare earth metals (which can be further utilized or used directly as trace element fertilizers). Not only is no more phosphogypsum produced, but all the existing piles of phosphogypsum can be converted into high-quality phosphate fertilizers with a water-soluble P2O5 content of over 12%, generating significant economic benefits. Currently, the utilization rate of phosphogypsum both domestically and internationally is less than 10%, and the amount of phosphogypsum stored is increasing. Only \"new-generation phosphorus chemical technologies\" can truly address this problem associated with phosphogypsum. (2) “Next-generation phosphorus chemical technology” is applicable not only to medium- to high-grade phosphate ores but also to low-grade ones; it is also the only viable method for utilizing low-grade phosphate ores apart from ore processing. The United States was the first to achieve industrialization of wet-process phosphoric acid using low-grade phosphate ores, but it ultimately gave up on this approach due to technical and economic reasons. In China, after more than 20 years of effort and significant investment in terms of funds and manpower, industrial facilities for wet-process phosphoric acid were built; however, due to unresolved technical issues, these facilities have not been able to operate stably to this day, and their prospects do not look promising. (3) “Next-generation phosphorus chemical technology” uses a wet-process method to produce phosphoric acid of the same quality as that obtained through thermal methods, directly from phosphate rock powder. It is simpler than the purification processes for wet-process phosphoric acid, requires lower costs, and is more advanced. “The \"new generation of phosphorus chemical technology\" involves the wet-process production of thermal acids, eliminating the need to use large amounts of electrical energy and avoiding severe environmental pollution associated with the production of yellow phosphorus, thereby offering high economic benefits. (4) Sulfuric acid is one of the main raw materials in modern (or traditional) phosphorus chemistry; 2.8 tons of sulfuric acid are required to produce 1 ton of phosphoric acid. Approximately 70% of the sulfuric acid used in China is spent on phosphorus chemistry production. \"New-generation phosphorus chemistry technologies\" can enable the recycling of sulfuric acid, thereby eliminating the need for it. (5) “Next-generation phosphorus chemical technology” not only eliminates pollution; it is itself a completely environment-friendly process that treats natural resources with care. It ensures the rational and most efficient utilization of all components of the raw materials. Through this technology, phosphate rocks not only provide phosphorus resources but also yield large amounts of high-purity calcium resources, sufficient fluoride resources, as well as valuable metal and rare earth metal resources. “The “new generation of phosphorus chemical technology” can truly solve a series of global challenges faced by modern phosphorus chemistry (or traditional phosphorus chemistry) that have remained unsolved to this day. Next, we will discuss the specific implementation projects of \"next-generation phosphorus chemical technologies\": 1. New process for wet-process phosphoric acid: Its features include (1) no generation of phosphogypsum; instead, high-value, high-purity, high-whiteness calcium sulfate or ultra-fine, ultra-white calcium carbonate and their related products are produced, as well as black residue that can be used as a micronutrient fertilizer ； (2) Rapid extraction: the extraction time at room temperature is reduced to 1–1.5 hours ； (3) The extraction is thorough, resulting in a high phosphorus yield; since there is very little black residue, the phosphorus content in it is low, as the amount of phosphorus lost due to the black residue is much less than that lost due to phosphogypsum ； (4) Extraction can directly yield phosphoric acid with a P2O5 content of around 40%, saving on the consumption of steam for evaporation concentration and electricity. II. Supercalcium carbonate technology: Supercalcium carbonate is a white crystal that contains up to 48-52% water-soluble P2O5; it is a high-concentration, high-quality phosphorus fertilizer and also a basic raw material for producing various phosphates. By adding supercalcium carbonate to the stored phosphogypsum, high-quality ordinary calcium phosphate with a P2O5 content of over 12% and full solubility in water can be produced, thereby eliminating the existing phosphogypsum and yielding significant economic benefits. III. Fluoride-free calcium feed production process: The so-called “fluoride-free” approach means that there is no separate fluoride removal step or associated operations; fluoride removal takes place automatically during the extraction process, and its effectiveness is much better than that of the current two-stage fluoride removal method. As a result, the production process for fluoride-free calcium feed is very simple, requires minimal investment, and has low operating costs. This method does not produce any calcium fertilizer, results in almost no loss of phosphorus, with a phosphorus recovery rate of over 98%. Additionally, the consumption of raw materials such as sulfuric acid and phosphate rock is significantly reduced. It is undoubtedly the most advanced production process for calcium feed available today. IV. Wet-process production of hot-process acid: Hot-process phosphoric acid is a basic raw material for the fine phosphorus chemical industry; it is produced from yellow phosphorus. Producing 1 ton of yellow phosphorus requires 14,000 kWh of electricity, and it also causes severe environmental pollution. Due to the high production costs of hot-process phosphoric acid, efforts have been made both domestically and internationally to obtain hot-process acid through the refinement of wet-process phosphoric acid (i.e., wet-process acid with quality similar to that of hot-process acid). Significant amounts of capital and manpower have been invested in China over several years, yet success has not been achieved. The “new generation of phosphorus chemical technologies” does not follow this approach; instead, it aims to produce hot-process acid directly from phosphorus ore powder using wet-process methods. This approach is clearly more advanced and feasible for the “new generation of phosphorus chemical technologies.” Positive laboratory results have already been obtained, which is of great significance for translating these research findings into industrial production. V. New process for phosphammonium production: The application of the new wet-process phosphoric acid technology in phosphammonium production results in a new manufacturing process for this compound. The characteristics of this new process are as follows: (1) No phosphogypsum is produced; instead, ultra-fine calcium carbonate and a small amount of slag containing various metal and rare earth elements are generated, with high revenue from these by-products ； (2) The extraction is rapid and thorough, resulting in a high phosphorus yield ； (3) Phosphoric acid containing about 40% P2O5 is obtained directly through extraction, and both steam and electricity consumption in the concentration process are reduced ； (4) A sulfuric acid-free process can be implemented to further reduce production costs. VI. The phosphate production process of “next-generation phosphorus chemical technology”: Currently, industrial-grade potassium dihydrogen phosphate is produced by neutralizing phosphoric acid with potassium hydroxide or potassium carbonate, which results in high production costs. In contrast, the “next-generation phosphorus chemical technology” uses potassium chloride and phosphate rock to produce industrial-grade potassium dihydrogen phosphate, with hydrogen chloride as a by-product; this approach offers very high economic benefits. “The new generation of phosphorus chemical technologies for producing monosodium phosphate, disodium phosphate, and pentasodium phosphate are similar in nature; they have very low production costs and thus offer high economic benefits. Suggestions for implementation (for reference): It is recommended to give priority to implementing the \"new phosphoric ammonium production process\" and the \"fluoride-free calcium feed production process\". (1) It can be modified on existing phosphoric ammonium production facilities, or it can be redesigned according to the \"new phosphoric ammonium production process\" by constructing new facilities to implement this new process; this way, the existing production is not affected, and the implementation of the new process is smoother. (2) Given the strong and stable market demand for calcium supplements for livestock, the \"fluoride-free production process for such supplements\" also possesses undeniable technical advantages; no manufacturers, either domestically or internationally, are able to compete with it. It is recommended to prioritize the development of this production method, with the goal of becoming the world’s largest supplier of calcium supplements for livestock within 2–3 years. “A full-page feature on the ultra-fine calcium carbonate, an important by-product of the \"new generation of phosphorus chemical technologies,\" was published in Page 7 of the China Chemical Industry News on February 13 this year; please keep an eye out for it.