Key points in the design of chemical production process flows

Thread Content

Key points in the design of chemical production processes I. Preliminary prerequisites for process design: When designing a production process, it is necessary to first determine the nature of the production method – mature processes can be used as a basis for partial improvements, while new processes require reliance on domestic pilot-scale data or established external information. The process is generally divided into four parts: raw material pretreatment, reaction, product post-treatment, and treatment of waste residues, waste water, and waste gas. II. The number of production lines is determined based on the variety count of products and the frequency of production changes; multiple production lines are set up in parallel as needed to meet the requirements for handling a variety of products and frequent production changes. III. Process construction centered on the reaction process: Based on material properties, production scale, etc., select the type of reactor and operating mode (continuous, batch, or a combination thereof). Also consider the energy requirements and supply for the reaction as well as the need for catalysts. First, focus on the main reaction process, and then gradually expand it to form a complete process. IV. Matching design for raw material pretreatment: Based on the requirements of the reaction regarding the purity and state of the raw materials, chemical unit operations such as preheating, purification, and mixing are combined to adjust the properties of the raw materials so that they meet the needs of the reaction. V. Key aspects of post-treatment of products: This involves addressing issues such as the separation of by-products, recovery of unreacted raw materials, removal of impurities, and adaptation of the physical phase state. Separation and purification steps are designed based on available data and experience; this is a crucial step in ensuring product quality. VI. Product post-treatment and material recycling: Carry out processes such as screening, packaging, storage, and transportation of qualified products as required ； Design a recycling method for unreacted materials, while separating and treating by-products. VII. Supporting facilities and safety and environmental protection designs shall ensure the comprehensive utilization of waste materials or their treatment to meet specified standards, in compliance with the \"three simultaneities\" principle for environmental protection ； Match utility facilities such as process water and steam ； Define equipment operating parameters and develop control plans ； Install safety facilities such as accident tanks and safety valves for safe production. VIII. The final design for insulation and corrosion protection determines the insulation requirements based on the medium temperature and environmental conditions, and selects appropriate materials accordingly ； Anti-corrosion measures such as linings and coatings are employed to address the corrosiveness of materials, while the consumption of relevant materials is also tracked. IX. Additional optimization points in process design
1. Efficient utilization of materials and energy: Improve the conversion rate of raw materials through advanced technologies and highly efficient catalysts ； Recycle unconverted materials and establish a recycling system for solvent-based unit operations ； Promote the comprehensive utilization of three types of waste ； Optimize the heat exchange process to recover heat ； Utilize the height difference of equipment and the static pressure energy of materials to convey them, thereby reducing energy consumption. 2. Rational configuration of unit operations: Select appropriate unit operations, determine their process schemes and equipment types, and arrange the sequence of the unit operations and equipment in a reasonable manner. 3. Controlling process flexibility and equipment utilization: The degree of process flexibility is determined through research and practice, with efforts made to ensure that the capabilities of various devices are matched in order to avoid waste of resources. 4. Improvement and simplification of the process: addition of backup facilities required for startup/shutdown and accident handling ； Simplify systems such as water and steam, reduce the amount of material circulation, and streamline processes by leveraging new technologies.