KD-6 Terpene Stripping SOP Number
51001
Revision Number
0
Revision Date
April 21, 2022 To provide a procedure for terpene stripping on the Chemtech Services, Inc. Mini-5 and KD-6 distillation system. This procedure applies to both the glass and stainless steel versions of the Chemtech Services, Inc. Mini-5 and KD-6 distillation systems. 51002 KD-6 Cannabinoid Distilling 52001 KD-6 Cleaning 52002 Leybold Vacuum Pump Oil Maintenance
Purpose Scope Referenced Documents Materials and Equipment
Appropriate PPE
Definitions
Turbo Pump: turbomolecular pump (Leybold Turbovac 90i or Pfeiffer HiPace 60P) Vacuum Pump: rotary vane vacuum pump (Leybold D8B) Turbo Valve: right-angle valve between the turbo pump and the system Vacuum Bypass Valve: right-angle valve between the vacuum pump and the system Bleed Valve: KF-16 needle valve
Prior to engaging in any of the procedures outlined below, operators must have an understanding of all steps and wear appropriate PPE.
Terpene Stripping Start Up Procedure 1. Turn on the circulators and set the temperatures according to Table 1 below. Table 1: Terpene Stripping Circulator Temperatures
Circulator Feed
Temperature (°C) 100°C
Residue
130-140°C
Evaporator
150°C @ 500-1000 micron 160°C @ 1000-1500 micron
Condenser
35°C
Cold Trap
-50°C
Notes Hotter residue temperatures can be utilized for material prone to “freezing up” in the non-jacketed sections or in an environment that is very cold that may cause “freezing” in the non-jacketed sections. Mini units – set the residue circulator to the same temperature as the feed. This temperature is feed dependent, meaning a faster feed rate may require a hotter evaporator (e.g., 170°C @ 500 micron). However, by increasing the feed rate where vacuum permits, the residence time of oil in the evaporator decreases. The key is to have a terpene COA so target volumes can be determined. Set the cold trap circulator to its lowest allowable temperature set point and run it as cold as possible.
2. Start the wiper motor when the evaporator circulator reaches 50°C and set it to half-speed according to Table 2. NOTE: There is a risk of deforming the PTFE wiper rollers if the wiper motor is not started before the evaporator circulator reaches 100°C.
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Table 2: Wiper Motor Speeds
Unit Type Stainless Steel Glass
Half-Speed 200rpm 125-150rpm
Run Speed 400rpm 250-300rpm
3. If applicable, protect the turbo pump by removing it from the system: a. For systems with a turbo bypass, close the turbo valve and open the vacuum bypass valve. b. For systems without a turbo bypass, remove the turbo pump from the system and assemble a KF-40 to KF-16 reducing piece in its place. Connect the bellows hose between the reducing piece and the vacuum pump. The turbo bypass kit is a highly recommended upgrade to avoid removing the turbo pump between terpene and cannabinoid passes. 4. Sample may be added to the feed tank when the feed circulator reaches the set point temperature. Stir the sample to ensure uniform temperature. 5. When the cold trap circulator reaches -30°C or lower, start the vacuum pump: a. Open the bleed valve. b. Turn on the vacuum pump. c. Close the bleed valve. NOTE: These steps prevent any potential shock from the vacuum to the glass of the system.
Terpene Stripping Procedure 1. Increase the wiper motor speed to the run speed according to Table 2 above. 2. When all set point temperatures and vacuum level are achieved, oil may be fed through the system. Turn on the feed motor and begin to feed sample through by removing the stopper. The feed rate will vary by system. NOTE: The introduction of vapor pressure coming off the sample will destroy vacuum. The feed rate may be adjusted based off of the vacuum. 3. Increase the speed as high as vacuum allows, but do not go beyond 5 Torr for terpene stripping. Aim to maintain the vacuum level below 2 Torr, but the ideal range is 0.5-1 Torr. 4. If applicable, start the discharge pumps: a. Allow the sight glass to accumulate approximately 300mL of material. b. For systems outfitted with check valves on the outlets of the discharge pumps, no priming is necessary. Open the valves below the sight glass, if applicable, and turn on the discharge pumps. NOTE: If the check valve was left with material inside from a wet shut down, then it may have “frozen open.” Simply heat gun the check valve so the highly viscous material can liquify and the spring in the check valve can close the check valve to create a vacuum seal. c. For systems without check valves: i. Allow the sight glass to fill to approximately 300mL prior to priming the pump. ii. Heat gun any non-jacketed sections containing cold oil from previous runs. iii. Turn on the discharge pump. iv. Plug the end of the gooseneck with a gloved finger. v. Slowly open the valve with the red handle beneath the sight glass. The vacuum will evacuate the air left in the gooseneck and the pump until the pump “catches” and starts to discharge the fluid. d. Adjust the discharge pump feed rate as necessary. NOTE: The discharge pump will always out-pace the fluid flow coming into the sight glass. The sight glass will appear empty, but as long as there is a constant flow of fluid entering the gears of the discharge pump, then the combination of the moving gears lubricated by fluid will create a vacuum seal. Page 2 of 4
e. Allow the discharge pumps to continuously discharge fluid into the preferred collection vessel.
Terpene Stripping Shut Down 1. If continuing directly to cannabinoid distilling, follow below, else, skip to #2: a. Turn off the feed motor and the vacuum pump when terpene stripping is complete. b. With the vacuum pump motor off, release the vacuum using the bleed valve. c. Re-install the turbo pump: i. For units with a turbo bypass, simply close turbo valve and open the vacuum bypass valve. ii. For units without a turbo bypass, re-install the turbo pump in place of the KF-40 to KF-16 reducing piece. NOTE: Complete this step very quickly to minimize the cold trap’s internal condensing surface to atmosphere with moisture. iii. Install the vacuum line to the turbo pump and plug in the power and communication cables. d. Continue on to the Cannabinoid Distilling Start Up Procedure outlined in the reference document 51002 KD-6 Cannabinoid Distilling. 2. When terpene stripping is complete, plug the feed tank with the stopper, then turn off the feed motor and the vacuum pump. NOTE: Always plug the feed tank BEFORE the tank empties completely to prevent air from aspirating into the system. 3. For units fitted with discharge pumps, close the valve under the sight glass, if applicable, and shut off the residue and distillate pumps. 4. Adjust the circulator temperatures according to Table 3 below. Table 3: Terpene Stripping Shut Down Circulator Temperatures
Circulator Feed Residue Evaporator
Temperature (°C) 50°C 50°C 50°C
Condenser
25°C
Cold Trap
-50°C
Notes
Lowering the condenser circulator temperature will help cool down the evaporator body faster. Additionally, a fan can be pointed at the evaporator body. Set the cold trap circulator to its lowest allowable temperature set point and run it as cold as possible.
5. When the evaporator temperature drops below 100°C, turn off the wiper motor and all circulators. 6. If running a large volume of material, then it is advisable to perform a cleaning run prior to starting cannabinoid distilling. Follow the cleaning procedure outlined in the reference document 52001 KD-6 Cleaning. 7. It is highly recommended to change the vacuum pump oil after terpene stripping and prior to distilling cannabinoids. Even further, a complete vacuum pump oil flush is preferred. Both of these procedures can be found outlined in the reference document 52002 Leybold Vacuum Pump Oil Maintenance.
Disclaimer Consult the acceptability of the above procedure against local codes. The customer takes part in the above outlined procedure at their own risk. Chemtech Services, Inc. assumes no liability for any damage to or loss of property.
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Revision History Revision 0
Date April 21, 2022
Changes Initial Release
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