Thread Content
Preparations for pilot testing and trial production and issues to note: I. Equipment selection and modification of process pipelines: 1. Based on the results of laboratory tests, equipment is selected in the multi-functional pilot plant; priority should be given to ensuring that the equipment capacity is appropriate, that the material of the equipment and pipelines is suitable for the process medium, that they are corrosion-resistant, and that the heating, cooling, and mixing speeds meet the required standards. 2. Methods of material transfer (feeding, discharging, transfer between various stages), and how to prevent issues such as material leakage, solidification, and blockages. 3. Methods for measuring and adding materials, such as how to effectively control dropwise addition? 4. Is any gas produced in the reaction? Will there be material overflow? If necessary, a gas-liquid separator should be added, along with a return pipe. 5. Are the separation conditions such as centrifugation and pressure filtration met? Based on the above conditions and other process requirements, the equipment and pipelines are adaptively modified. II. Preparations before feeding materials: 1. The equipment, especially newly installed or refurbished equipment, as well as equipment that has not been in use for a long time, must undergo pressure testing and leak testing. These tests should be carried out in conjunction with cleaning operations, so as to ensure that no further welding is required after materials are fed in. Insulation for the equipment’s pipelines should be applied once there are no leaks. 2. Carry out proper cleaning of the equipment and clearing of the work area to ensure that no debris enters the reaction system, prevent cross-contamination, and maintain an orderly working environment. 3. Determine the feeding coefficient based on process requirements and experimental needs, calculate the amount of materials to be fed, ensure that raw materials are issued in a coordinated manner, maintain quality standards, use clear labeling, and arrange them in a categorized and designated manner. 4. Plan for and prepare the containers and storage areas for the intermediates. 5. Inspection of production conditions: Check whether steam, oil baths, cooling water, and saltwater are flowing properly (you can test this by feeling the temperature difference before and after the valves are opened), and ensure that the valves operate as required. 6. Is the material homogeneous? Is the mixing sufficient to ensure uniform distribution? Do solids settle in the recesses of the bottom valve, especially solid catalysts or poorly soluble raw materials? What measures can be taken to prevent such deposition? 7. Are all the instruments functioning properly? It is necessary to determine whether a thermometer can be inserted into the material throughout the entire process (when there are changes in the level of the material and when too little material is added). 8. Prepare proper operating procedures and safety regulations. 9. Train employees in process-related skills (especially by clearly explaining the control parameters and key points, the hazards of violating operating procedures and the layout of pipelines, as well as the control mechanisms for valve operation); meanwhile, implement emergency measures for situations where control parameters are exceeded or emergencies occur. Conduct safety training and occupational health training. 10. Identify the persons responsible for the project, organize the shift schedule properly, assign key personnel to assist, and establish clear methods for communication between workers, key personnel, and higher-level management during nighttime. 11. Prepare emergency response plans and carry out the necessary preparatory work. III. Precautions during the production process: 1. Operate strictly in accordance with the operating procedures and safety regulations; no arbitrary changes are allowed. If new issues are found that require changes, there must be a solid basis provided by preliminary tests. 2. Strictly control reaction conditions such as temperature and pH value; if these parameters exceed the specified limits, appropriate actions must be taken promptly (this should be considered during pilot testing, and destructive tests should be conducted to find solutions). 3. Pay attention to the differences in heat transfer sensitivity of thermometers during pilot production compared to pilot testing, as there is a delay in temperature changes, and relevant actions should be taken in advance to account for this. 4. How to inspect and take emergency measures in case of a leak in the vacuum system, especially under high-temperature conditions, when emergency actions must be taken promptly. 5. In the event of a sudden power outage, loss of steam, water supply, or chilled brine supply, necessary emergency measures must be taken immediately (including using backup power sources and N2 protection when required). 6. Pay attention to the amplification effect in the production process; it is generally necessary to proceed step by step rather than focusing solely on speed, as trying to rush things will not yield good results – a gradual approach is essential. 7. Due to unforeseeable factors and amplification effects, the amount of material fed in each batch must be controlled, and a hierarchical approval system should be implemented. 8. Carefully and thoroughly observe the phenomena that occur during the reaction process, keep accurate records in a timely manner, and analyze these phenomena promptly; it is also necessary to carry out preliminary tests or follow-up verifications. All relevant personnel must have a high sense of responsibility, closely monitor the entire production process, and take timely action to address any issues that arise. 9. There must be clear indicators and methods to determine the end point of each step; strict control is applied at each stage, and this can be assessed in combination with the phenomena that occur during the reaction. 10. Choose the appropriate post-treatment method. Unit operations such as extraction, crystallization, and recrystallization are carried out; when selecting extractants and solvents, the principle of \"like dissolves like\" is properly applied to take into account the solubility of impurities and the product. When selecting a solvent, it is necessary to consider not only the suitability for the process but also economic and practical factors such as price, toxicity, and whether it can be recycled or is easy to recycle. These aspects should be taken into consideration when carrying out post-treatment in pilot tests. IV. Safety issues: 1. Thorough pilot testing is the guarantee of success in pilot-scale production and full-scale manufacturing. Efforts should be invested in pilot testing to consider in detail all aspects related to the implementation methods and operability during pilot-scale and production phases; the more careful and thorough such considerations are, the smoother the pilot-scale production and manufacturing process will be, with fewer production and safety accidents occurring. 2. The safety of technical modifications is crucial for safety efforts. Since multiple projects are carried out in the same workshop, one project may be undergoing technical modifications while other projects are in production; or within the same system, one product might have been manufactured previously and now another product is being produced instead; or technical modifications may be carried out midway due to issues that were not anticipated in advance. In any case, whenever work involving open flames can be carried out outside the workshop, it must be done there; efforts should be made to avoid performing such work inside the workshop. If it is absolutely necessary to carry out the work inside, thorough cleaning and isolation measures must be taken (including of equipment, containers, and pipelines), ensuring that no hidden areas remain. Strict rules regarding the use of open flames must be followed. 3. Employee training and strict adherence to rules, regulations, and operating procedures are key aspects of safety work. 4. The division of responsibilities must be clear; before starting production, the “Trial Production Project Overview Table” should be filled out to identify the responsible persons. Communication among them should be timely, strict systems and a high level of responsibility are essential. Key personnel should be on site, and appropriate measures should be taken promptly in case of any issues. 5. Potential safety issues, environmental protection problems, and labor protection issues should be anticipated in advance, and corresponding measures should be taken. Most importantly, developers need to be cautious; many problems cannot be anticipated and must be resolved on the spot. Thermometers must have dual displays, as a single thermometer is prone to malfunctioning. Pilot testing and trial production are different from regular production, as the critical processes are closely related to the design. 1. Equipment used for pilot testing and trial production should be like training cars for learning to drive, equipped with emergency control systems ； 2. Before pilot testing and trial production begin, it is necessary to design alternative operating procedures (determined based on the operating conditions for material feeding), conduct tests to ensure that the facility meets the process requirements, and provide training for employees ； 3. For pilot testing and trial production, it is necessary to design adequate sampling plans and sampling points, as well as determine the appropriate storage conditions for the samples, so that in cases where the results are normal, a comparison analysis can be conducted with the results obtained from pilot tests ； As well as cause analysis in abnormal situations. This post was last edited by Jiangchengzi on 2008-5-17 09:05.]