News

Some knowledge points of steam ejectors

2022-01-04


A steam ejector is a special device for increasing the pressure of low-pressure steam. Its principle is to use the high-speed air flow generated by high-pressure steam (working steam) injection to increase the pressure and temperature of low-pressure steam, so as to increase the pressure and temperature of low-pressure steam to the indicators required by the production process and achieve the purpose of energy saving.
  
Steam ejectors can be used in the following ways:
  
Low-pressure steam pressurized reuse: Some companies use several different pressures of steam at the same time, but the heat source cannot meet all of them. At this time, some low-pressure steam can be pressurized with a steam ejector to meet the needs of industrial production.
  
Recycling of equipment exhaust steam: Some equipment that uses steam cannot be reused due to the low exhaust pressure. The steam ejector can integrate the pressurized spent steam into the steam supply network to realize the recycling of spent steam.
  
Recovery of flash steam: The flash steam generated after condensate enters the flash tank is sucked in by the steam ejector and pressurized for production or daily use.
  
Advantages of steam ejector: simple structure, no rotating parts, long service life, reliable operation, easy installation and operation, convenient maintenance. The energy saving effect is remarkable.
  
Precautions for the installation and use of steam ejectors
  
(1) Install all components correctly according to the equipment installation drawings, and tighten all standard parts.
  
(2) Before starting, use the steam preheating pipeline and steam injector, first open the outlet mixing steam valve and the working steam valve in turn, and then open the injector steam valve.
  
(3) When stopping, the injector steam valve should be closed first, and then the working steam valve and the outlet mixed steam valve should be closed in turn.
  
The steam ejector coupling is used to maintain the communication of the control signal between the solenoid valve and the electronic control unit in the ejector. According to the received throttle sensor, speed, water temperature, common rail pressure, etc. The ECU sends instructions to the injector solenoid valve to control the start time and stop time of the injection, so as to achieve the purpose of adjusting the advance angle of fuel supply and the amount of fuel injection, so as to control the speed and torque of the engine.
  
The steam ejector is mainly composed of a nozzle, a receiving chamber, a mixing chamber and a diffusion chamber. The working principle of steam jet pumps is that when high-pressure steam passes through the nozzle, a high-speed air flow is generated, creating a low-pressure area at the nozzle outlet. In this area, low-pressure steam is inhaled. The high-pressure steam compresses the low-pressure steam while expanding, and the residual pressure of the high-pressure steam increases the grade of the low-pressure steam. Then the mixed steam is mixed evenly through the mixing chamber, and then a part of the pressure is recovered through the diffusion chamber, and the required steam pressure is reached and supplied to the hot user. According to the parameters of high pressure and low pressure steam, different structural designs can be carried out to obtain steam of different pressure levels to meet the needs of different heat users. The inhaled low-pressure steam can be either exhaust steam or flash steam produced by condensate, making full use of low enthalpy heat energy and achieving energy saving. The energy saving rate of steam jet pumps can reach about 35%, which is very practical.

 

 

News