What is a direct steam injection heater?
A direct steam injection (DSI) heater is a method of heat transfer that takes advantage of direct contact between steam flow and a process fluid to heat the fluid. With DSI all the steam energy is absorbed into the process flow, taking advantage of 100% heat transfer.
How is Pick steam injection technology different?
Pick was the first to develop and optimize the use of a heating/mixing chamber with internal injection tube design. To heat liquids, steam is dispersed across a pattern of precisely arranged orifices, injecting steam into many fine streams promoting rapid mixing and instantaneous heat transfer. As the steam enters the internal injection tube it acts against a spring-loaded piston to expose some or all the orifices. As the steam input varies due to load changes the piston responds to adjust the number of exposed orifices providing rapid response to process changes.
The spring and piston arrangement ensures that there is always sufficient steam pressure at point of injection, eliminating harmful shock and vibration caused by steam hammer. The helical flights inside the chamber promote complete and thorough mixing of steam and liquid.
All steam is condensed in the heater body, not in customer downstream piping.
What are the advantages of using a Pick direct steam injection heater?
• Low Liquid Pressure Drop - Less Than 2 PSI (0.14 BAR)
• Efficient - Save Up to 28% in Fuel Costs
• No condensate return required.
• Exceptional Temperature Control - +/- 1°F
• Wide Operating Range
• Stable, smooth operation.
• Low Noise Level - Typically Below 85dBA
• Complete Mixing in Heater Body.
• Instantaneous response to load changes
• Compact Design
• Low Maintenance Cost
• No downstream minimum Straight-run Piping to further condense steam.
What are some of the applications for direct steam injection heaters?
Steam injection heaters are a versatile and efficient way to heat a variety of fluids in a variety of industries. Pick DSI heaters are ideally suited for heating water or water miscible liquids wherever precise temperature control, energy savings and ease of installation and operation is desired. It is an ideal alternative where a shell-and-tube or plate heat exchanger is being consider for heating with steam.
Common applications include:
Food Processing Industry:
- Hot water for plant clean up and sanitation
- Wastewater heating
- FOG separation
- Equipment cleaning and CIP
- Hot water for jacketed kettles
- Hot water sets for plate heat exchangers
- Freezer defrost
- Nitrogen injection into product
- In-line product cooking and pasteurization
- Confectionery/starch cooking
Chemical and Pharmaceutical Industry:
- Jacketed reactor vessels for heating and heat/cool processes
- Tank car washing
- Jacketed rail cars
- RO water heating
- Bio-waste inactivation
Pulp and Paper Industry:
- Paper machine showers
- Felt showers
- Brown stock washing
- Starch cooking
- Boiler feed water
How do I choose the right direct steam injection heater for my application?
Pick Heaters offers a wide range of direct steam injection heaters to meet the needs of a variety of applications. Read our blog post How to Choose the Right Pick Direct Steam Injection Heater for Your Needs for detailed information.
What are the steam and liquid pressure requirements of the Pick Heater?
A key benefit of the Pick design is the low liquid-side pressure drop of 2 psi or less. The required liquid pressure is only driven by the process requirements. Steam supply pressure to the Pick system should be a minimum 20 psi greater than the liquid side pressure in order to allow for the controlled drop across the steam valve and heater’s internal steam injection tube.
My previous heating system created steam hammer; do I need to worry about that with a Pick Heater?
The key to steam injection is to harness the condensing of steam into the process fluid quickly, in the mixing body of the DSI unit. This is accomplished with the Pick design through low velocity mixing and the breaking up of steam across the multiple orifice pattern. Most other DSI units rely on high velocity mixing action which requires further mixing in downstream piping. Customer downstream piping is not designed to handle the sudden condensing of steam. The longer it takes for steam to condense, steam atomization will recombine and suddenly implode, taking place in process piping. The result is cavitation and hammer. This is simply not the design of the Pick DSI Heater.
What materials of construction are Pick Heaters made with?
Pick’s standard heaters are manufactured in Cast Iron, Carbon Steel, or 316SS.
Sanitary heaters product surfaces are 316L Stainless Steel with #4 (32 Ra) sanitary polish and carry the 3A symbol.
Specialty fabricated heaters can also be made in special alloys such as AL-6XN, Hastelloy, Duplex 2205, Titanium, Inconel etc.
What type of boiler do I need?
Clean steam with little or no moisture or contaminant carryover, at the required horsepower for all steam usage in the plant is required.
Medium to high pressure boilers are best as direct injection requires higher pressure steam to inject into a lower pressure liquid. Steam supply pressure at the Pick heater location must be a minimum of 20 psig greater than the process/liquid pressure.
The type or brand of boiler does not matter if it can provide a steady steam supply at the pressure and flow rates required.
What is the steam quality required to operate a Pick Heater?
Clean steam with little or no entrained water or contaminants is ideal for any plant steam supply. Boiler carryover, or “wet steam” can cause serious hammer issues in the steam header and negatively affect how steam mixes with the process at the Pick heater. As small amounts of water enter the system, the water flashes to steam when pressure is reduced in a regulator or control valve. Often the result is unstable operation.
The cause of wet steam can be a sudden increase in load or running the boiler in excess of design load. Ineffective or poor operating steam traps or separators also contribute to excessive moisture in the steam supply.
Can Pick Heaters be used for personnel/home use?
No, Pick Heaters are only for industrial use only.
Are Pick steam injection heaters in stock/on the shelf?
No, our heaters are designed and manufactured based on each customer's operating conditions.
Can a Pick Heater be installed horizontally?
Yes, while the preferred method is vertical installation discharging up or down, horizontal installation may be the customer preference due to space constraints or when replacing existing equipment. You will want to consult with Pick representative about your specific installation and review any potential long-term effects of horizontal operation.
How do I calibrate my pneumatic temperature controller?
The Pick system can be instrumented with various methods of temperature control. The most basic option is the pneumatic controller. This simple device holds temperature setpoint to within +/-3F, acceptable for most basic water heating applications. The controller is a non-indicating device. At initial start up the controller knob may need to be calibrated so that the numbers on the controller face plate will correspond with the actual temperature. Watch the demonstration video on the Videos page of this site. You can also find information in the Installation and Operation Manual. If you do not have a copy, you can request one providing us with the model and serial number of your Pick Heater.
Where can I locate my serial number?
The serial number of your Pick Heater is located on the name plate along with the top and bottom casting.
How can I get a copy of my user manual?
You can request one providing us with the model and serial number of your Pick Heater.
Does Pick Heaters work with distributors?
No, Pick uses factory trained manufacturer's representatives in defined territories. To find out who your local representative is, contact us.
Do you have multiple representatives in my area?
No, each representative firm has a defined, exclusive territory and there is only one Pick Heaters rep in each territory. To find out who your representative is contact us.
How do I find out who my local authorized factory representative is?
You can complete the contact us form and request your rep's information.
Where can I get a copy of Pick's Terms & Conditions?
The local Pick representative quoted me, who do I make my purchase order out to - Pick Heaters or the rep?
All purchase orders should be made out to Pick Heaters, Inc., West Bend, WI. Purchase orders may be sent directly to Pick Heaters, Inc. or in care of your local representative.
Do you accept credit cards for payment?
Yes, we take Visa, Mastercard, American Express, and Discover.