1、 First step: System emptying and residual cleaning

Residual wastewater and concentrated solution can easily cause pipeline blockage and component corrosion, which is the first problem to be solved after shutdown.

Drain all liquids: After closing the inlet valve, sequentially drain the raw water, concentrated liquid, and distilled water from the evaporator to ensure that there is no residual liquid in the evaporation chamber, storage tank, and pipeline.

Rinse the core flow channel: Rinse the evaporation chamber, heating tube, and circulation pipeline with clean water (or neutral cleaning agent according to the type of wastewater), focusing on cleaning possible salt and organic residue that may adhere, to avoid scaling and blockage after drying.

Discharge cleaning wastewater: After flushing, thoroughly drain the cleaning wastewater to prevent the cleaning agent from reacting with residual pollutants and producing corrosive substances.

2、 Special maintenance of core components

Different components have different materials and functions, and require targeted maintenance to avoid aging or failure of critical components.

1. Maintenance of vacuum pump

Check the working fluid: If it is a water ring vacuum pump, replace or supplement the working fluid (clean water) to avoid residual impurities in the working fluid blocking the pump body; If it is an oil type vacuum pump, the color and purity of the oil should be tested, and if it deteriorates, it should be replaced in a timely manner.

Sealing protection: Close the inlet and outlet valves of the vacuum pump, wrap a dust-proof cloth around the interface to prevent dust from entering the pump body and affecting the efficiency of the next vacuum pumping.

2. Compressor maintenance

Pressure release: Slowly open the exhaust valve of the compressor to release residual internal pressure and avoid long-term pressure that may cause aging of the seals.

Lubrication protection: If the shutdown time exceeds one month, manually rotate the compressor crankshaft (according to the equipment manual) to ensure that the internal lubricating oil evenly covers the components and prevent rusting and jamming of bearings and other parts.

3. Maintenance of evaporation chamber and heating components

Drying treatment: Use compressed air to blow dry the inner wall of the evaporation chamber and the surface of the heating tube, or turn on the "air drying mode" of the equipment (if any), to avoid residual moisture causing metal parts to rust.

Scaling inspection: If slight scaling is found on the surface of the heating tube, it can be cleaned with a soft bristled brush or a specialized descaling agent (matching the material of the heating tube, such as strong acid descaling agents are prohibited for stainless steel). Scratching with hard objects is strictly prohibited to prevent damage to the coating of the heating tube.

4. Valve and instrument maintenance

Moving parts: Rotate valve handles one by one (such as inlet valves and drain valves), apply a small amount of food grade grease (or equipment specific grease) to prevent valve jamming.

Instrument protection: Wipe the surfaces of pressure gauges, level gauges, and temperature sensors with a dry cloth, check if the instrument connection wires are loose, and finally cover the instrument panel with a dust cover.

3、 Additional protection for long-term downtime (downtime exceeding 15 days)

If the downtime is long, targeted protective measures need to be added to avoid long-term idle damage to components.

Rust prevention of pipelines and inner walls of chambers: Dry nitrogen gas (or rust inhibitor, in accordance with equipment material requirements) is introduced into the evaporation chamber and critical pipelines to form a protective layer, preventing corrosion caused by air and moisture.

Electrical system protection: After turning off the main power, check whether there is moisture in the electrical control cabinet, place desiccants (such as silicone bags), and replace them regularly; If the environmental humidity is high, it is necessary to power on once a month (without load) and use the device's own heat to drive moisture.

External protection: Cover the entire equipment with a dust cover to prevent dust and debris from accumulating; If the equipment is installed outdoors, additional rainproof and antifreeze measures should be taken (such as wrapping insulation cotton to prevent residual moisture in the pipeline from freezing and cracking).

4、 Record and check: leave a basis for the next startup

After maintenance is completed, it is necessary to keep records for quick troubleshooting before the next start-up.

Fill out the maintenance record form: record the downtime, maintenance date, maintenance items (such as "vacuum pump oil change" and "heating tube descaling"), any problems found (such as "slight valve leakage"), and sign for confirmation.

Pre check before startup: Note in the record sheet the key items that need to be checked before the next startup, such as "confirming the working fluid level of the vacuum pump" and "checking for leaks in the heating tube", to reduce the risk of malfunctions during startup.