Stafford, Texas

PSC Controlled Evaporation System, Vapor Generation

PSC Controlled Evaporation System, Vapor Generation

The PSC Controlled Evaporation System is a vapor generation system that is capable of generating low flow vapor streams. This system is an alternative to traditional bubbler systems and provides a highly precise, repeatable, and controllable vapor generation process in ready-to-use/out-the-box or customizable packages, which includes:

Our fully integrated packages come prebuilt or they can be custom designed to fit your exact project requirements. Our packages arrive assembled and ready for use and are backed by our technical support team.


Our vapor generation systems contain a user-friendly, HMI touchscreen interface. Its programming allows users to easily control flow rates, set points, temperature, stop/start, and concentration / composition of the vapor stream. Input / Output is also conveniently available on the control unit to allow users to easily connect various flow meters and flow controllers, change carrier gas, and process liquids.

Applications Benefitting from Precision Vapor Generation

The low flow capabilities of our CEM Controller makes for an easy, all-in-one vapor generation system. This evaporation system is an especially useful device for laboratories, research purposes, and intricate manufacturing processes. Common applications include precise batching of additives in food and beverage manufacturing and chemical vapor deposition (CVD) processes.

Table Top or Rack Mounted Vapor Generation System

Our original design for a vapor generation system includes a table top controller, which allows users to easily move and store the vapor generator when not in use. The rack mount system is generally ideal for laboratory environments offers the same easy control. Additionally, the rack mount CEM Controller can control up to three different vapor generation systems via three separate evaporator mixers and supplemental flow controllers for gases and liquids. The rack mount CEM Controller can operate each of the three systems separately, but it can also control them as part of a single system.

Advantages over Traditional Bubbler Systems

The CEM Controller offers highly accurate, repeatable, and also efficient vapor generation and analytical tracking. Traditionally, bubbler systems are often not capable of handling sufficient quantities of liquid with a low vapor pressure, or perform in an imperfect way. Moreover, they cannot instantaneously provide vapor of a mixture of liquids with different vapor pressures.

CEM Controller for Vapor Generation

The CEM Controller is a modular setup with the Controlled Evaporative Mixer (CEM) itself as the core component. A CEM is a mixer and vaporizer that uses heat to atomize a liquid, which is then mixed with a carrier gas. The carrier gas and liquid mixture is then heated and transformed into vapor phase, which can then be used for precise, low flow vapor control. And to feed the CEM with liquid and gas, the CEM is setup with a liquid flow meter with a control function and a gas flow controller. The liquid flow meter also uses the mixing valve of the CEM to control the liquid flow rate.

Controlled Evaporation Technology

The gas serves as a mixing component and as a means of transport for the vapor and is therefore known as ‘carrier gas’. The mixing valve atomizes the liquid and adds it to the carrier gas, creating an aerosol, which is heated by the CEM until it transforms into a vapor. To monitor the internal temperature of the heat exchanger, the CEM incorporates a PT100 temperature sensor. Additionally, an internal safety switch prevents overheating of the heat exchanger, by interrupting the control signal as soon as the temperature reaches 392˚F. 

All-in-One Vapor Generation Device

To control the liquid and gas supply flows and the CEM temperature, the CEM Controller integrates the flow instrumentation with an HMI touchscreen controller with GUI read-out that also serves as a power supply unit. The controller also comes equipped with Modbus interface programmed for the CEM system. The CEM Controller also contains a temperature controller for the heat exchanger and provides a user interface to operate the instrumentation. Additionally, the HMI controller provides data logging of instrument data and WebMI capabilities. The WebMI empowers users to control everything onscreen from a computer, tablet, or other mobile devices. 

Ready-to-Use / Out-the-Box Packages Available:

  1. 7” Color Touchscreen PLC – Process control, monitoring, data logging, remote access
  2. Controlled Evaporation Mixer (CEM)Temperature and heating, vaporizer, mixing chamber
  3. Heat Trace – Control temperature through outlet
  4. Heat Trace Temperature Verification – Process temperature thermocouple connection
  5. Liquid Meter and ControllerRemote control outlet
  6. Gas ControllerRemote control outlet
  7. Mini-USB Connection – Program PLC
  8. USB Connection – Data transfer or storage
  9. Modbus MJ2 – Power (+) – communicates and powers meters/controllers
  10. Modbus MJ3
    • additional Modbus RTU communication port
    • does not control CEM system
  11. Ethernet Lan1
    • Program PLC
    • Additional communication port
  12. Power with on/off Switch
  13. Additional Ports
Gas Flow Controller

The choice of gas flow controller depends on the specific requirements of the application. The gas flow controller is used to supply carrier gas to the CEM for the vaporization of the desired liquid. Common choices include thermal mass flow meters such as the EL-FLOW Prestige or IN-FLOW for higher flow rates or Coriolis based flow meters such as the mini CORI-FLOW. Our engineers will work with you to help determine which Bronkhorst flow meter will work best for your process.

Liquid Flow Meter

The choice of liquid flow meter and controller is typically a mini CORI-FLOW since this instrument offers unmatched precision and functional capability. Additionally, the mini CORI-FLOW can handle a wide range of liquids of various viscosities and corrosive properties. This device is used to precisely supply the CEM with liquid for the vaporization process. However, other flow instrumentation may be chosen depending on the specific requirements of the user and application.

CEM-Controlled-Evaporation-Mixer-for-Vapor-GenerationControlled Evaporative Mixer (CEM)

The CEM is the heart of the controlled evaporation system. This device is equipped with an atomizer, which is used to vaporize the liquid, which is then mixed with the carrier gas in the mixing chamber.

HMI Touchscreen Controller

Our Vapor Generation Controller generally features a 7” color touchscreen for an indication of measured values. Additionally, the HMI unit offers user friendly process control and comes preprogrammed with high functionalities specifically for vapor generation processes. The touchscreen easily enables the user to change the setpoints and other functions. The controller also powers the devices and communicates via Modbus to control the CEM temperature and the instruments’ flow rates. Additionally, the controller offers a temperature traced vapor outlet and the option for additional gas or liquid instruments.