STANDARD OPERATING PROCEDURE Jet Cooker with Pump and Hydro-heater Manufacturer: Hydro-Thermal Corporation Location: Wet Processing Pilot Plant, 1091 Food Sciences Building Publication Date: 07/23/2014 Iowa State University does not discriminate on the basis of race, color, age, ethnicity, religion, national origin, pregnancy, sexual orientation, gender identity, genetic information, sex, marital status, disability, or status as a U.S. veteran. Inquiries regarding non-discrimination policies may be directed to Office of Equal Opportunity, 3350 Beardshear Hall, 515 Morrill Road, Ames, Iowa 50011, Tel. 515 294-7612, email eooffice@iastate.edu.
Description and Uses Jet cookers are used to mash samples by direct contact with steam, therefore, they should be connected to only culinary steam, as house steam is contaminated with inedible boiler additives. In an ethanol production unit, automatic hydro-heaters are being used to cook corn slurries in plants producing up to 60-million gallons of alcohol per year. Jet cookers are commonly used for both enzymatic and acid conversion processes. In smaller plants, delivering up to 3-million gallons per year, complete liquefaction and saccharification systems are used. Power Specifications Motor: General Electric Power: ¾ HP Voltage/Amperage: 200V/3.8A Motor Speed/Frequency: 1725 rpm @ 60 Hz. Potential Hazards and Safety Precautions Electric Shock/High Voltage (200-220V) Make certain to use the correct outlet that is specifically designed to fit the electrical cord plug. Make sure the area around the outlet, floor and your hands are completely dry when plugging or unplugging the electrical cord to/from the outlet. Moving Parts and Pinch Points/Possible Entanglement of Extremities, Hair, Jewelry or Clothing The jet cooker operates with moving parts that can create possible pinch points. Keep extremities (especially hands), hair, jewelry and clothing clear of all moving parts while the cooker is in operation. Make sure to secure long hair and any loose clothing or jewelry before operating the jet cooker. Flying Debris/Potential Eye Damage Always use proper personal protective equipment at all times while operating the jet cooker. Very High Temperatures and Hot Surfaces/Possible Burns to Skin and/or Extremities The jet cooker uses steam and operates at very high temperatures. Keep hands and extremities away from steam and heated tubes while the jet cooker is in operation. Heat-resistant gloves and smock should always be worn to avoid potential burns or injury. High Pressure/Possible Explosion The jet cooker operates under high-pressure using steam that is derived from a boiler. Any boiler malfunction can possibly lead to an explosion. As a result, never operate the boiler and/or jet cooker without direct supervision and training from the pilot plant manager. 2
Required Personal Protective Equipment Safety Goggles Protective Footwear (No Open-toed Shoes) Lab Coat Hair Net (tie back long hair) Heat-resistant Gloves Long Pants and Long Sleeves Heat-resistant Smock No Loose Fitting Clothing Training Required Training *Denotes courses offered online Fire Safety & Extinguisher Training* Laboratory Safety: Core Concepts* Machine & Site-Specific Training Recommended Training for Frequent Users *Denotes courses offered online Electrical Safety & Lockout/Tagout Laboratory Safety: Spill Procedures Shop Safety Fundamentals: Basic Procedures & Policies* 3
Operation Note: Never operate the jet cooker or boiler without direct supervision and training from the pilot plant manager! Use of the jet cooker requires manual operation with threaded connections that heat above 212ºF (100ºC). For operation instructions on heating below 212ºF (100ºC) or air-actuated hydroheaters that operate below or above 212ºF (100ºC), please refer to the equipment manual located in the pilot plant office, 1955 Food Sciences Building. 1. On high-temperature applications, the back pressure required to prevent flashing should be at least 3 psi higher than the saturation pressure given in the steam tables. The liquid-supply pressure should exceed the back pressure by at least 15 psi or more. Steam- supply pressure should exceed the back pressure by 2 times or higher. Note: Both of these supply pressures should be constant if the heating system is to operate within a uniform discharge temperature. 2. The combining tube is factory set to a 50%-open position. Marks scribed on the position scale block and on heater body indicate a relative or pre-set combining-tube position (see Figure 1). 3. Be sure that both the steam-supply and liquid-supply valves are fully closed (see Figure 2). Once the supply valves are closed, set the downstream back-pressure valve about 50% open. Then, fully open liquid-supply line valve and start the pump. 4. Adjust the pumping rate or set the throttling valve to obtain the desired flow rate. 5. Fully open the steam-supply valve. Figure 1 6. Open the steam flow-adjustment hand wheel until the temperature reaches about 220ºF (105ºC). Figure 2 4
7. Adjust the back-pressure valve until the back pressure for the desired discharge temperature is indicated on the gauge. 8. Adjust the hand wheel until the required discharge temperature is obtained. If the operating conditions are not the same as before, adjustments may be required to re-establish optimum levels. 9. If necessary, close the combining tube until smooth operation of the heater is obtained per instructions given in Bulletin H-114 of the equipment manual. The manual is located in the pilot plant office, 1955 Food Sciences Building. Minor adjustments of the steam flow rate, liquid flow rate, and back-pressure may be necessary. 10. For operation shutdown, please refer to clean-up procedures. Clean-up Procedures 1. On slurry applications, flush out the hydro-heater and the downstream piping system with hot water at end of each cycle. 2. Close the steam-supply line valve. Then, turn off the pump and close the liquid-supply line valve. 3. Leave the hydro-heater hand wheel, combining tube, and the back- pressure valve settings unchanged. 4. Once the jet cooker has cooled, perform a wet spray down with tap water to clean the cooker. Hand wash any parts of the machine that are unclean or have remaining debris. 5. Clean and mop the surrounding work area. 6. Have the cleaned machine and work area inspected and approved by the pilot plant manager. 7. Initiate check-out procedures. Machine Care and Maintenance Inspect the machine after every use for any leakage or broken parts. Note: All final inspections are performed by the pilot plant manager. Report any operational difficulties, leaks or broken parts to the pilot plant manager before leaving the work area. For detailed maintenance procedures, please refer to the equipment manual, located in the file cabinet in the pilot plant office, 1955 Food Sciences Building. Accessories None 5