Detailed introduction
　　I. Overview of Single-effect Concentrator
　　Single-effect concentrator, also known as single-effect external circulation concentrator, single-effect external circulation evaporator, or single-effect external circulation vacuum concentrator, is suitable for the concentration of liquid materials such as traditional Chinese medicine, western medicine, glucose, starch, monosodium glutamate, dairy products, oral liquid, chemical industry, food, etc., especially for low-temperature vacuum concentration of heat-sensitive materials. The single-effect concentrator has the advantages of fast concentrating speed, short time, multi-purpose in one machine, atmospheric pressure, vacuum concentrating and paste collecting. The single-effect concentrator (single-effect external circulation concentrator) consists of heating chamber, evaporation chamber, foam trap, condenser, cooler, receiving tank, valve fittings of inner connecting pipe of the system, supporting instruments, etc. The contact part with materials is made of stainless steel 304/316L, which is corrosion resistant and beautiful in appearance. There is heat preservation outside the heater and evaporator. The outer insulation is made of stainless steel plate. The surface is treated by mirror or matt, which fully meets the GMP standard. The heater of single-effect concentrator adopts fast-opening structure, which is convenient to clean. The inner part of the heating chamber is tubular. The shell side is connected with the raw steam, and the liquid inside the tube is heated. The adding chamber is equipped with pressure gauges and safety valves to ensure the safety of production. The front of the separation chamber is equipped with a viewing mirror for the operator to observe the evaporation of material and liquid. The back manhole is convenient for cleaning the interior of the chamber when the variety is changed. A thermometer and a vacuum meter are also provided to observe and master the temperature of material and liquid in the evaporation chamber and the vacuum degree during negative pressure evaporation.
　　II. Working Principle of Single-effect Concentrator
　　The raw steam enters the shell side of the heating chamber, heating up the feed liquid in the tube side, spraying it into the evaporation chamber from the jet tube for vapor-liquid separation, and the feed liquid returns to the lower part of the heating chamber for reheating. The feed liquid is heated and sprayed into the evaporation chamber to form a cycle. When the material is concentrated to a certain extent, after sampling is determined, the material is discharged from the discharge port. The steam evaporated from the evaporation chamber is removed by the foam eliminator, and then cooled by the condenser and cooler to form liquid into the liquid receiver. Finally, the non condensable gas is discharged into the atmosphere or evacuated by a vacuum pump.
　　3. Operational Rules of Single-effect Concentrator
　　1. Necessary work before operation:
　　(1) Before operation, check whether the equipment, valves and instruments are normal, whether the pipeline is unobstructed and there is no leakage. Clean the equipment only if there is no abnormality.
　　(2) Check whether the heater and evaporator are cleaned.
　　(3) Check whether the valves are in the correct opening and closing position. Only after the re-examination is correct can it be operated and used.
　　2. Driving:
　　(1) Open the vacuum valve;
　　(2) Open the feeding valve and close the feeding valve when the liquid is seen in the viewing mirror of the evaporator.
　　(3) Open the condenser and circulating cooling water. The water pressure is stabilized at 0.1-0.2 MPa.
　　(4) Slowly open the steam valve. The evaporator is heated to the required pressure to heat the evaporator.
　　3. Normal operation:
　　(1) Adjust the opening degree of the feed valve, control the liquid level to maintain a certain height, so that the evaporation of liquid medicine and the supplement of liquid medicine can reach a dynamic balance.
　　(2) Every 2 hours or so of evaporation, the exhaust valve of the heater is opened and the non-condensable gas is discharged.
　　_The discharge of condensate water is about 15-20 minutes apart from the separate discharge of heater condensate water.
　　The emission steps are as follows:
　　A. Close the water valve;
　　B. Open the exhaust valve to make the water tank change from vacuum to empty.
　　C. Open drainage valve and discharge condensate water.
　　D. After the condensate water is discharged, the drain valve should be closed first, then the exhaust valve should be closed, and the water supply valve equipment should be opened for normal operation.
　　4. Parking:
　　(1) Close the steam valve and stop supplying steam;
　　(2) Close the vacuum butterfly valve;
　　(3) Open the evaporator exhaust valve to destroy the evaporator vacuum and put down the extract during concentration.
　　(4) Open the exhaust valve and drain valve to drain the condensate;
　　(5) Clean evaporators and heaters.