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CMS CO 2 Cooling System Design Elements. Erik Voirin Mark Adamowski. Topics. Design Parameters System Overview Specific Equipment Info Control System Info Safety Commissioning Procedure. Design Parameters. Deliver Saturated or slightly sub cooled CO 2 to the detector
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CMS CO2 Cooling SystemDesign Elements Erik Voirin Mark Adamowski CMS Pixel Mechanical Upgrade
Topics • Design Parameters • System Overview • Specific Equipment Info • Control System Info • Safety • Commissioning Procedure CMS Pixel Mechanical Upgrade
Design Parameters • Deliver Saturated or slightly sub cooled CO2 to the detector • Ability to handle 15-60 psi detector pressure drops • Ability to handle any vapor quality at the detector outlet • Capacity to handle up to 5 kW heat load • Ability to provide liquid CO2 at -30 °C to +15 °C • CO2 quality at detector outlet of 25%, maximum • CO2 side, design pressure of 1200 psig CMS Pixel Mechanical Upgrade
Cooling System Overview CMS Pixel Mechanical Upgrade
1400W 2400W 4800W CMS Pixel Mechanical Upgrade
Commercial Refrigeration Units • Three Mechanical refrigeration chillers will be used to cool the CO2 reservoir. These are commercial, off the shelf units, capable of providing refrigerant to the CO2 condenser at -40 °C. Use of commercial packages provides proven refrigeration technology at reasonable cost using R404A. CMS Pixel Mechanical Upgrade
Cooling System Overview • Versatile System Control: • Seven steps of cooling capacity, with trim heater to trim final cooling capacity from 0 to up to 20,000 Watts from -40C to 20C CMS Pixel Mechanical Upgrade
System Cooling Capacity CMS Pixel Mechanical Upgrade
Design Elements • Closed CO2 Cooling Loop • Design pressure of 1200 psig • At 30 °C the CO2 equilibrium pressure is 1031.6 psig. • Vessels are ASME rated at 1200 psi, tested at 1560 psi • Flanges are class 600, rated at 1480 psi • Pump housing tested at 1827 psi • Valves/Unions/Fittings rated minimum of 1480 psi • ½” to 1-½” Sch 10 stainless steel rated minimum of 1916 psi CMS Pixel Mechanical Upgrade
Storage tank Condensers Trim Heater Variable Speed Pump -------> to detector CMS Pixel Mechanical Upgrade
Storage Tank • ASME Vessel - 12” schedule 80s stainless seamless pipe • Will be filled with up to 300 lbs CO2 • Three condensers mounted on flanged ends CMS Pixel Mechanical Upgrade
CO2 Condenser • Heat will be removed from the CO2 tank by CO2 condensers. The CO2 wetted components will be stainless steel for corrosion resistance. Corrosion would produce exchanger fouling and reduce condenser capacity. • The cooling fluid to the CO2 condenser will be refrigerant R-404A. CMS Pixel Mechanical Upgrade
Design Elements • Electric CO2 Trim Heater • An electric heater will be used as a trim control in holding a particular CO2 coolant temperature. • 0-6000 Watt capacity electric resistance heater. • Bayonet style. • Housed in ASME vessel • Coaxial 2” in 4” pipe • Heater housed inside 2” pipe • Heat Flux from 0 – 18500 W/m2 CMS Pixel Mechanical Upgrade
Pump • Warrender High Pressure WMDAT6-2S • Alloy Dual Stage Regenerative Turbine Mag-Drive Pump • Flow up to 32 gpm (2250 grams/sec ) • Duty Point is 11.2 gpm @ 64 psi (788 grams/sec at 440kPa) • Variable speed – 3 HP motor (2240 Watts) • Hydrostatically Pressure Tested at 1827 psi (12.6MPa) CMS Pixel Mechanical Upgrade
Control Valve CO2 Drier Phase Separator Flowmeter CMS Pixel Mechanical Upgrade
Phase Separator • Quality into the phase separator would be at a maximum of 5% • Passive liquid full design with control valve on mixture outlet • ASME vessel rated to 1200 psi • Mixture outlet flow controlled by manual V-ball valve CMS Pixel Mechanical Upgrade
CO2 Drier • Ice and/or carbonic acid will form if the water concentration reaches a level above the solubility limit in liquid CO2. Ice can plug small channels and carbonic acid is corrosive. Controlling the water content in the CO2 is critical. • Original plan was to use a desiccant filter, however 1200 psi rated filter housing are unavailable. • Desiccant granule bed with granules held in class 600 strainer CMS Pixel Mechanical Upgrade
Additional Experiment Flanged connections Pressure Differential Transmitter Test Heater CMS Pixel Mechanical Upgrade
Detector Test Stand • Detector Test Stand – Identical to Trim Heater • An electric heater will be used as a detector test stand for simulating detector heat load. • 0-6000 Watt capacity electric resistance heater. • Bayonet style. • Controllable manually from PLC • Housed in ASME vessel • Coaxial 2” in 4” pipe • Heater housed inside 2” pipe • Heat Flux from 0 – 18500 W/m2 CMS Pixel Mechanical Upgrade
Detector Test Stand • Flow estimates through actual detector tubes at a set pressure drop 0.15 MPa have been calculated. • Test stand will have an orifice placed at the opening to replicate the pressure drop of 0.15 MPa (21.75 psi) at the calculated total detector flow rate of 138 grams/sec. CMS Pixel Mechanical Upgrade
Control System • Beckhoff PLC • Touch Screen Controller • Control and data retrieval via network CMS Pixel Mechanical Upgrade
CO2 Flow Control • The flow of CO2 to the detector will be measured after the phase separator. • A differential pressure transmitter will be in place across the detector test stand . • The CO2 pump will be controlled by motor on a speed controller (variable frequency drive) controlled by either: • Flow rate of CO2 after phase separator • Differential pressure across detector test stand CMS Pixel Mechanical Upgrade
CO2 Temperature Control • The pressure of the CO2 supply tank can be used as an indication of CO2 temperature through the saturation pressure / temperature relationship for CO2. The CO2 tank pressure can then be used as the control to turn the refrigeration ON/OFF to maintain the CO2 temperature (pressure). • The storage tank is equipped with a temperature element as well for comparing the pressure measurement. • Any value down to -40C may be input through the touch screen. • The PLC will cycle the chilling units and Trim heater to achieve desired temperature • Response time = roughly 5 minutes for 0C to -20C change • Response time = roughly 17 minutes for -20C to 0C change CMS Pixel Mechanical Upgrade
Safety • Pressure Vessel notes for four ASME vessels are out for review • CO2 Hazard Analysis out for review • Per FESHM 5064 procedures • Piping Notes being prepared will comply with: • Warning signs / tags per FESHM5051 • Per FESHM 5051 and ASME 31.3 Code for process piping • Welder qualified under ASME Section IX CMS Pixel Mechanical Upgrade
Safety - Piping • Piping Notes being prepared – solid models of each pipe section is constructed and analyzed in Ansys under conditions: • 1200 psi internal pressure + weight of pipe • Drop in temperature from 71.6F to -110F + weight of pipe • Minimum -40C operating temperature and internal saturation pressure of 131psi CMS Pixel Mechanical Upgrade
Safety – CO2 Hazard • CO2 Hazard – Occurs before ODH • 5000 ppm/0.5% - TWA (Time Weighted Average, 10 hr) • 30,000 ppm/3.0% - STEL (Short Term Exposure Limit) • 40,000 ppm/4.0% - IDLH (Immediately Dangerous to Life and Health) • 100,000 ppm/10%, produces unconsciousness in a matter of minutes. CMS Pixel Mechanical Upgrade
Safety – CO2 Hazard • CMS Document 2966 by Erik Voirin covers CO2 hazard – 32 pages • Ventilation Fans • CO2 Monitors and Warning Systems - (In both lab C and clean room) • Air flow Monitors – (On ventilation fans of both rooms) • Actuated Isolation Valve CMS Pixel Mechanical Upgrade
Safety – CO2 Hazard Proactive Steps aimed at personnel safety: • Regarding the Clean Room • Trouble alarm at 0.3% CO2 • Trouble alarm if the fresh air makeup is off • Close isolation valve and stop pump at 0.5% CO2 • Evacuate at 2% CO2 concentration • Regarding the Lab C hallway • Trouble alarm at 0.3% CO2 • Trouble alarm if local exhaust fan fails regular test • Start exhaust fan at 0.5% CO2 • Evacuate at 2% CO2 concentration CMS Pixel Mechanical Upgrade
Commissioning Plan • Pressure Transmitters • Check each instrument is wired to correct input by directly applying pressure read by gauge to specific transmitters, watch touch screen for proper location • Temperature Elements • Direct immersion into water baths of know temperatures, check for correct wiring and readout. • Air Flow Monitors • Check for proper operation by removing from air flow path, make sure correct alarms signals are sent. CMS Pixel Mechanical Upgrade
Commissioning Plan • CO2 Monitors • Test with known CO2 composition air mixtures • Check trouble signals sent through FIRUS • Check evacuation horns and light activate as set • Check activation of Lab C exhaust fan • Actuated Valve • Check for manual activated closure • Test automated closure by tripping CO2 monitor CMS Pixel Mechanical Upgrade
Commissioning Plan • Chillers • Performance Test: activate each chiller with closed storage tank and observe dT/dt and dP/dt. • Trim Heater • Equipped with power monitor. Measure units output vs. input. Compare to claimed 6000 Watt output rating. • Pump • Equipped with pressure differential transmitter. Piping has flow meter. Test output of pump at various flow rates and differential pressures. Compare to claimed capabilities. CMS Pixel Mechanical Upgrade
Commissioning Plan • Test Heater • Equipped with power monitor. Measure units output vs. input. Compare to claimed 6000 Watt output rating. • Performance Tests Using Test Heater • Check systems cooling capacity of system up to 6000 Watts from -40C to 15C. • Record all data from instruments CMS Pixel Mechanical Upgrade
Design Parameters Met • Deliver Saturated or slightly sub cooled CO2 to the detector • Ability to handle 15-60 psi detector pressure drops • Ability to handle any vapor quality at the detector outlet • Capacity to handle up to 5 kW heat load • Ability to provide liquid CO2 at -30 °C to +15 °C • CO2 quality at detector outlet of 25%, maximum • CO2 side, design pressure of 1200 psig CMS Pixel Mechanical Upgrade
Questions? CMS Pixel Mechanical Upgrade
Additional slides CMS Pixel Mechanical Upgrade