1Laboratory homogenizerPre-operation preparation
Personnel Qualification and Protection
Operators need to receive professional training, be familiar with the equipment structure, working principle, and safety regulations, and are strictly prohibited from operating without a license.
Wear protective equipment: safety helmet (buffer layer, securely fastened straps), protective goggles (polycarbonate lenses, light transmittance ≥ 90%), acid and alkali resistant gloves (nitrile rubber, thickness ≥ 0.5mm), anti slip work shoes (anti smashing steel head), protective apron (chloroprene rubber, covering the chest and legs).
Familiar with first aid knowledge, the laboratory is equipped with first aid kits and fire extinguishers.
Equipment and environmental inspection
Equipment status: Check that the shell is not damaged or deformed, the anchor bolts are tightened (torque 30-50N · m), the cross-sectional area of the grounding wire is ≥ 4mm ², and the connection is firm.
Pipeline system: The connecting hoses of the feed and discharge ports are not aged or damaged, the clamps or flanges are tightly connected, and the valve core and seat of the homogenization valve are not worn (visually inspect the surface for scratches or dents).
Electrical system: The power supply voltage meets the requirements (380V ± 10%, three-phase five wire system), the insulation layer of the power line is not damaged, the plug and socket are intact, and the grounding resistance is ≤ 4 Ω.
Environmental requirements: There are no flammable or explosive materials around the equipment, the passage is unobstructed, the ambient temperature is ≤ 40 ℃, and the humidity is ≤ 80%.
Material preparation
The sample should be a homogeneous fluid, and materials containing solid particles or high viscosity should undergo high shear treatment. Hard particles with a diameter greater than 0.5mm or materials containing plant roots and stems are not suitable.
The material needs to be filtered through a 60-100 mesh filter to prevent impurities such as iron and glass fragments from entering the equipment.
Material temperature ≤ 80 ℃ (high-temperature materials need to be cooled in advance), viscosity ≤ 500cP, to prevent pump body overload.
2、 Standard operating procedures
Pre startup inspection
Confirm that the pressure handle is in a relaxed state, the pressure gauge is reset to zero and displaying normally, and there is material or water or 20% ethanol in the feeding system.
After the equipment is moved, it is necessary to check the installation level and ensure that the power phase (motor direction) is correct. It is strictly prohibited to turn on the homogenizer valve while the handle is tightened.
Startup and operation
Start sequence: Turn on the power switch, wait for the device to self check, press the "jog" button (time ≤ 3 seconds), confirm that the motor direction is correct, press the "start" button to run without load for 5 minutes, and listen for no abnormal noise (normal is uniform mechanical operation sound).
Pressurization operation: Rotate the pressurization handle clockwise and slowly apply pressure at a constant speed (about 100bar/10s). The pressure should be ≤ the rated value of the equipment (usually ≤ 1800bar) to avoid overpressure.
Feed control: Open the feed valve, start the material conveying pump, control the feed pressure at 0.1-0.3 MPa, ensure that the material fills the pump body, and discharge air (continuous discharge from the discharge port without bubbles).
Parameter adjustment: Adjust the flow rate according to the viscosity of the material (flow range of 0.5-5m ³/h for high-pressure homogenizers), synchronously adjust the pressure, and maintain stability (fluctuation ≤± 2MPa).
operation monitoring
Pressure and temperature: Record the homogeneous pressure every 10 minutes. When the pressure suddenly increases (exceeding the set value by 10%), immediately open the bypass valve to reduce the pressure and stop the machine for inspection. Monitor the outlet temperature through the device thermometer and ensure that it does not exceed the allowable value (such as 100 ℃). For high-temperature materials, the cooling system must be turned on.
Sealing and vibration: Check that there is no leakage in the pump head, homogenization valve, and pipeline interface. The plunger seal is allowed to leak at a rate of ≤ 1 drop per minute (if exceeded, the seal needs to be replaced). The amplitude of the equipment is ≤ 0.1mm (measured with a vibration meter), and the foundation is not loose.
3、 Risk prevention and control measures
Mechanical injury prevention and control
It is strictly prohibited to touch moving parts (such as motors and transmission shafts) during equipment operation to prevent hand pinching or getting involved in accidents.
It is strictly prohibited to open the hood or disassemble components during equipment operation. The machine must be stopped and powered off before operation.
Material leakage prevention and control
Regularly check the wear of seals (such as O-rings and valve body gaskets) and replace aging or damaged components in a timely manner.
When dealing with corrosive materials, choose corrosion-resistant materials such as 316 stainless steel and polytetrafluoroethylene.
Electrical safety prevention and control
When the insulation layer of the power cord is damaged, immediately stop the machine and replace it. Live maintenance is strictly prohibited.
Test the grounding resistance monthly to ensure it is ≤ 4 Ω and prevent electric leakage and shock.
Overpressure and overload prevention and control
Install pressure regulating valve and safety valve (with a popping pressure of 1.1 times the working pressure), and regularly test the sensitivity of the safety valve.
Avoid prolonged high load operation to prevent motor overheating or pump damage.
4、 Emergency response process
Emergency response to material leakage
Immediately stop the machine and cut off the power supply, close the feed valve and discharge valve to prevent the leakage from expanding.
Wear protective equipment to clean up leaked materials. Corrosive materials need to be treated with neutralizing agents (such as sodium bicarbonate for acid leaks and boric acid for alkali leaks).
Check for leaks, replace seals or repair pipelines.
Emergency response to equipment malfunction
Motor malfunction: Stop the machine and cut off the power supply, check if the motor bearings and windings are damaged, and contact professional personnel for repair.
Abnormal pressure: Check if the homogenization valve is blocked or if the pressure reducing valve is malfunctioning, clean or replace the components.
Excessive noise or vibration: Stop the machine and check if the anchor bolts are loose, if the rotor is balanced, adjust or replace the components.
Emergency response for personnel injury
Mechanical injury: Immediately stop the machine, apply pressure to the wound to stop bleeding, and in severe cases, seek medical treatment.
Chemical burns: Rinse the injured area with plenty of water for at least 15 minutes, select a neutralizing agent based on the properties of the material (such as 2% sodium bicarbonate solution for acid burns and 1% acetic acid solution for alkali burns), and seek medical treatment.
Electric shock: Immediately cut off the power, use an insulated object to open the wire, perform cardiopulmonary resuscitation on the person with cardiac arrest and respiratory arrest, and call 120 emergency number.
Fire emergency
Immediately stop the machine and cut off the power supply. Use a dry powder fire extinguisher or carbon dioxide fire extinguisher to extinguish the fire (water is strictly prohibited).
When the fire cannot be controlled, quickly evacuate the scene, call the 119 fire alarm number, and notify the laboratory safety officer.
5、 Shutdown and maintenance
Shutdown procedure
Stop adding samples, wait for the material in the homogenizer to be emptied, and then rotate the pressure handle counterclockwise to release the pressure (about 100bar/10s).
Gradually stop high-pressure pumps, homogenizers, and other equipment to ensure smooth shutdown.
Turn off the power switch and clean the surface and surrounding environment of the equipment.
Laboratory homogenizerroutine maintenance
Cleaning: Rinse the pipeline with clean water after each use, clean oily materials with alkaline solution or detergent, and finally cycle clean with pure water several times.
Lubrication: Check the lubricating oil (grease) level of the motor bearings and high-pressure pump plunger sealing chamber every week, and promptly replenish or replace it (model 3 # lithium grease or food grade white oil).
Tightening: Check monthly whether the connecting bolts of each component of the equipment are loose and tighten them in a timely manner.
regular maintenance
Quarterly: Open the feed/discharge valves to check for material accumulation and residue, clean and replace seals.
Every six months: Open the homogenization valve group to check the sealing and wear condition, replace the aging O-ring and sealing gasket.
Every year, professional personnel are commissioned to conduct comprehensive maintenance of equipment, calibrate pressure gauges, safety valves, and other safety accessories.