Precautions for the oil removal process using heat exchanger baffle plates

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I. Chemical degreasing: 1. The choice of detergent should be based on the type of oil buildup on the baffle plates – whether it is animal or vegetable oil, or mineral oil – as well as the degree to which the oil buildup is stubborn. For example, for baffle plates containing a large amount of animal and vegetable oils, alkaline cleaners can be given priority ； If the oil contamination is mainly mineral oil and a high degreasing speed is required, organic solvent cleaners may be more suitable, but care must be taken regarding their safety. When selecting an organic solvent, it is necessary to ensure that it does not undergo a chemical reaction with the material of the baffle plates; for example, baffle plates made of certain plastics may be corroded by strong organic solvents. 2. Concentration and temperature control: For alkaline cleaners, their concentration must be strictly controlled. Too high a concentration may corrode the baffle plates, while too low a concentration results in poor oil removal efficiency. Generally, the concentration of sodium hydroxide solution should not exceed 10%. When heating is used to enhance the effect of chemical degreasing, care must be taken to ensure that the temperature does not exceed the limit tolerable by the material of the baffle. For example, certain metal baffle plates may deform or experience changes in performance at high temperatures; generally, it is advisable to keep the heating temperature between 60 and 90°C. 3. Safety and environmental protection: Organic solvents are highly volatile, flammable, and toxic; therefore, they should be used in well-ventilated areas, away from sources of fire and heat, to prevent fires and poisoning incidents. The waste liquid resulting from chemical cleaning must be treated in accordance with environmental protection requirements; it cannot be discharged arbitrarily to avoid environmental pollution. II. Physical oil removal: 1. For high-pressure water flushing, the appropriate flushing pressure should be adjusted based on the material and structural strength of the baffle plates. Excessive pressure can damage the baffle plates, especially those that are thin or have a fragile structure; therefore, the pressure is generally kept between 5 and 20 MPa. When rinsing, pay attention to the direction of the rinse flow to ensure that all areas are reached, thereby preventing any oil residues from remaining in hidden spots. 2. The pressure and temperature of the steam used for vapor purging to remove oil are controlled to prevent the baffle plates from deforming or being damaged due to overheating or excessive pressure. The steam pressure is generally between 0.5 and 1.5 MPa. When using steam for purging, it is necessary to ensure the safety of the surrounding environment to prevent operators from being scalded by the steam. III. Other aspects 1. Inspection before degreasing: Before degreasing, it is necessary to inspect the appearance and structure of the baffle plates, and record any damage or special structural features, so that appropriate protective measures or special degreasing procedures can be adopted during the degreasing process. 2. After degreasing, check the effectiveness of the baffle in removing oil to ensure that all grease has been completely eliminated. Visual inspection or some simple testing methods (such as checking for residual oil on a cloth after wiping) can be used. Check whether the degreasing process has caused damage to the baffle plates, such as deformation, corrosion, or surface scratches.