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“The proprietary “semi-hydrated to dihydrated wet-process phosphoric acid” technology is a prime example of China Wuhuan Engineering Co., Ltd., a subsidiary of China National Chemical Engineering, diligently implementing the Group’s “T+EPC” model. This technology has been successfully applied and promoted in numerous turnkey projects involving wet-process phosphoric acid production. As a critical process in phosphate production projects, the anti-corrosion work determines the reliability of the plant’s performance as well as its operational efficiency in later stages. The reaction vessel is the core component of semi-hydrate and dihydrate wet-process phosphate production projects; it is in this vessel that phosphate is produced through the mixing and reaction of phosphate rock and sulfuric acid. This process is characterized by high reaction temperatures and strong corrosivity, which makes anti-corrosion treatment of large-scale reaction vessels a top priority in phosphate production projects. Currently, the wet phosphoric acid project in Huiyang, Hubei is in the peak phase of anti-corrosion construction; let’s take a look at the rubber lining installation in the large-scale reaction tanks. The construction of a rubber lining for a reaction tank involves 20 distinct processes, including substrate treatment, material testing, moisture content inspection, application of an epoxy primer, application of a conductive leveling layer, lining the top and sides with rubber, spark testing, treatment of the bottom conductive layer, lining the bottom with rubber, further spark testing, and final joint inspection. These numerous procedures require not only thorough treatment of the concrete structural substrate but also careful preparation of key materials such as rubber sheets and adhesives. Additionally, it is essential to strictly control air humidity and temperature to meet the requirements for construction. Only by ensuring strict control over each of these processes can a high-quality and standard-compliant rubber lining for the reaction tank be achieved. Strictly enforce the regulations regarding technical instructions and work in confined spaces. Before construction, carry out thorough technical instructions in accordance with the specific construction plan, explaining the key points and challenges of the work. Workers must undergo training and pass examinations before they can start working. It is also necessary to maintain proper records of work carried out in confined spaces, and to conduct regular tests and monitoring of harmful gases, in order to ensure safe and orderly construction. Treatment of the concrete substrate in the reaction tank and preparation of the adhesive sheets: The inspection of the concrete substrate in the reaction tank should ensure that it is dense, free from swelling, porosity, or inclusions. After grinding, its flatness and roundness must meet the acceptance standards. After sandblasting, the roughness should be greater than 90um, thereby creating favorable conditions for the subsequent processing steps. Strictly control the temperature and humidity of the working environment. After the concrete substrate of the reaction tank has been prepared, heating and drying equipment is used to determine the moisture content of the substrate; the standard of a moisture content of ≤5% is strictly enforced. By testing the moisture content of the concrete substrate, measuring the humidity inside the tank, and conducting joint inspections, it is ensured that the preconditions for rubber lining installation are met. All performance tests are carried out simultaneously. Before the reaction tank is lined with rubber, experiments on the formulation of epoxy putty, its tensile strength, adhesion, compressive strength, etc., as well as tests on the hardness of the rubber sheets and their tensile and adhesive properties, must be conducted rigorously. Valid and accurate test reports must be obtained to ensure that the properties of the epoxy putty and rubber sheets meet the standard requirements. Construction of the conductive layer in the concrete matrix of the reaction tank: The construction of the conductive layer in the reaction tank must meet the standards of even application, a smooth surface, and no bubbling or honeycombing. This ensures that the matrix is smooth and even; it also facilitates electrical spark testing after the gasketing is completed, thereby ensuring that there are no damages or holes in the gasket material. Gasketing of the reaction tank’s concrete substrate: After the conductive leveling layer of the reaction tank has been approved, a primer and adhesive should be applied, ensuring that there are no missed areas, no drips, and no accumulation of material. Heating and dehumidification equipment should also be used; the gasketing process should be carried out when the air humidity is within the required range, with 100% compaction achieved, resulting in no bubbles or warping. A demonstration session on the high-quality acceptance of rubber lining for reaction tanks was held. On October 31, the high-quality completion of the rubber lining work for the reaction tanks was assessed, and the project owner expressed great satisfaction with the company’s work. Taking this as a model case, a demonstration and exchange session on standardized management of rubber lining construction was organized under the theme of \"using demonstrations to promote learning and standards to drive practice.\" The general manager of the project owner led a group of 30 representatives from other related companies in attending this session for learning purposes.