Organic solvent spray dryers are critical equipment for processing flammable and explosive materials. Proper maintenance not only extends equipment life but is also a crucial measure to ensure production safety. The following is a systematic maintenance plan:
I. Daily Maintenance (After each experiment)
1. Cleaning the spray system is the primary task. Immediately after the experiment, rinse the feed lines, nozzles, and atomizers with the corresponding solvent. For viscous materials, soak them in hot solvent before cleaning to prevent clogging. Use special tools when disassembling the nozzles, and dry and store them after cleaning to prevent damage to the atomizing components.
2. The drying chamber and separator should be handled after the equipment has cooled to room temperature. Clean the residual powder from the drying chamber and cyclone separator. Use a solvent-soaked cloth to wipe stubborn stains, avoiding scratching the inner wall. Also, check the condition of the sealing rings and clean any adhering materials to prevent leaks.
3. The solvent recovery system inspection is crucial. Drain the solvent from the condensation recovery device, clean the recovery bottle, and check for blockages in the pipelines. Monitor the condensation effect; any abnormal frosting should be addressed promptly.
II. Regular Maintenance (Weekly/Monthly)
1. Mechanical component maintenance includes lubricating the atomizer and fan bearings, and replacing aging peristaltic pump tubing. Adjust the tension of the drive belt to prevent slipping or excessive wear.
2. The electrical and control systems require regular inspection of power cords and plugs for safety, and cleaning the control panel to prevent liquid ingress. Calibrate the temperature/pressure sensors to ensure accurate parameter detection.
3. Safety device calibration is critical. Test the oxygen concentration sensor (accuracy ±0.1%) and nitrogen flow controller to ensure oxygen concentration ≤3%. Verify the explosion-proof pressure relief valve activation threshold (0.02 MPa) and the multi-stage alarm mechanism.
III. In-depth Maintenance (Quarterly/Semi-annually)
1. Atomizer key inspection: Pressure nozzles must be disassembled to check for wear on the orifice. Severely worn nozzles must be replaced. The centrifugal atomizing disc needs to be inspected for wear and sent to a professional manufacturer for dynamic balance calibration.
2. System Performance Calibration: Calibrate the feed pump using a standard flow meter; adjustments are required if the error exceeds ±3%. Perform two-point calibration on the hot air temperature probe to ensure a temperature control accuracy of ±2℃.
3. Comprehensive Electrical System Inspection: Test the motor insulation performance and check if the frequency converter, PLC, and other control components are functioning normally. Replace all O-rings to prevent leakage due to rubber aging.
IV. Special Precautions
1. The inert gas system requires regular inspection of nitrogen purity (≥99.995%) and the airtightness of the circulation pipeline to prevent air ingress. Regarding corrosion prevention, stainless steel components should avoid prolonged contact with strong corrosive solvents, and glass components should be handled with care.
2. Safety requirements during operation include wearing a gas mask, fire-resistant clothing, and safety goggles at all times. The operating room should be well-ventilated and equipped with a flammable gas alarm. The emergency stop button must be kept readily accessible.
V. Trends in Intelligent Maintenance
Modern organic solvent spray dryers use a 15.6-inch explosion-proof touch screen to store process recipes, supporting remote parameter adjustment and fault diagnosis, reducing the frequency of manual intervention. The dual-channel nitrogen supply system and dual pressure monitoring enhance safety.
Through standardized maintenance, the organic solvent spray dryer can maintain an operating efficiency of over 95%, extend the service life of core components by 30%-50%, and ensure production safety and product quality.