Heat transfer solutions Thermocompressors
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Variable orifice SJT Steam Jet Thermocompressors Spirax Sarco offers several types of Thermocompressor. The first is the fixed nozzle type which cannot be controlled to any great extent, although some control is achievable by throttling the motive steam pressure via a separate valve upstream of the SJT Steam Jet Thermocompressor (See Control Option 1, page 5, for subsonic units). The other type relies on a motive steam regulating spindle to vary the cross sectional area of the motive steam nozzle (Control Option 2, page 5,). Unlike a throttling valve positioned upstream, the regulating spindle does not reduce the motive steam pressure, it simply varies the area through which the steam is flowing. This approach maximises the energy per kg of motive steam that is available at the nozzle to do the work. With an installation involving an upstream throttling valve, useful energy is lost in the throttling process. SJT Steam Jet Thermocompressors utilizing a motive steam regulating spindle are often referred to as Variable Orifice Ejectors. The spindle is operated automatically. These should be specified in cases where the suction load, suction pressure or discharge pressure are continually varying, and it is necessary to control one or more of these process parameters as quickly as possible. Note: For cases which involve large variations in load, it is sometimes more cost effective to use several various sized units connected in parallel, than to have one large controlled unit. It may also be necessary to install a bypass valve in some applications. Online calculation software Example A client wishes to recover 1 500 kg/h steam from a flash vessel which operates at 0.1 bar g and wants to compress it to 1.5 bar g to be used in a process. HP steam is available at 20 bar g, dry and saturated. The water flow to the flash vessel can vary. The pressure in the flash vessel must not fall below 0.5 bar a.
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Flash vessel
Method We can use the Spirax Sarco Online Sizing Software to design a suitable unit (available at www.spiraxsarco.com with password). When the calculation button is pressed, the software will calculate the required Motive (HP) steam flowrate and the unit connection sizes. The user will see a summary screen, at which point the desired flange rating can be selected and then the 'Save & Email' button can be pressed - A Datasheet and GA Drawing, page 7, will then be sent to your chosen email address. The software will automatically determine if the unit is Sonic or Subsonic and designed accordingly.
SJT Steam Jet Thermocompressor Quote Welcome to the online quote system. Please complete the details below:
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TI-P493-02 TES Issue 3
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SJT Steam Jet Thermocompressor
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