Heating, Air Conditioning, Fridge, HVAC/Force Air Heater


Spray Dryer
Spray Dryer  

Gas Burner
Gas Burner  
Hi, I am making a small-scaled spray dryer. It's a 3.2ft diameter by 26ft high vertical tube, a funnel is attached.

From the base, I intend to introduce heat that will fetch some 400 deg centigrade air temp at the top (internal) of the dryer, please view attached sketch.

I intend to use propane for the heat, it is forced air gas fired system. i have fabricated it and it gave me 700deg centigrade air temp. Air flow from blower was about 150cfm.

The dryer is not enclosed, the open funnel is at the base of the dryer, for product collection.

My question is: From your huge experience in heat transfer systems, do you think I will get upto 400deg centigrade at the top (internal) of the dryer?

Please view attached sketch showing spray dryer and the gas burner I made.


Obi ,

To me if your getting 700 degree from the nozzle , and moving it at 150CFM upwards of 24 feet and the the hole (  3' 2" Diameter ) by the slurry is located seems only a few inches  in diameter , I don't think you would have a problem with getting 400 degree C in that area . I find it hard to believe you could lose that much temperature ( starting at 700 degree ) and loose over 300 degree traveling just 24 feet. Isn't there codes you need to follow in regards to the the wall temperature of your spray dryer ,such as it needs a outer sleeve a certain distance from the dryer for safety consideration , or any type of safety controls or a blower motor designed to handle the high temperature ( even thou the motor is upstream of the flame , heat transfer due to convection ) Does your Insurance Company approve of your design and will cover claims if something happens to the building or personal . I would think no , as this is not from a manufacture who specializes in this type of system who has meet all the codes and certifications

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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