Abstract:
A dual heating process is performed in the absence of an open flame. Heat is created by a rotating prime mover(s) driving a fluid shear heater. Heat is also collected from a cooling system of the prime mover, and from any exhaust heat generated by the prime mover. The heat energy collected from all of these sources is transmitted through heat exchangers to a fluid where heat energy is desired. The fluid being heated may be glycol or air, depending on the type of heat desired.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention generally relates to processes used to provide heat for industrial processes, where the heating process does not require an open flame. 
       BACKGROUND OF THE INVENTION 
       [0002]    Industrial applications may require warm air and fluid heating capabilities of various types to avoid freezing and provide a safe, comfortable work environment. Specific environments may require that no open flame be present. This most commonly occurs in the energy industry. The present invention was created to heat air and fluids in these environments. 
         [0003]    The present invention allows the opportunity to eliminate inefficient, labor intensive, and hazardous boilers, heat fluids contained in various tanks, thaw ground or other strata, and provide warm air in various applications. This process provides warm air and glycol at user specified ratios, and can be combined with a variety of heat exchangers to transmit the heat to a desired location. The heating process is efficient and safe, making the best use of fuel in a flameless environment. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention consists of a number of major components which are connected in such a way that the process provides efficient, flameless heat. The components are generally trailer mounted, but may also be truck or skid mounted. 
         [0005]    The largest component is the prime mover. The prime mover is most often a diesel engine, gasoline engine or natural gas engine. An electric drive may also be used depending on the environmental considerations. 
         [0006]    Connected directly to the drive shaft of the prime mover is a dynamic heater, such as a fluid shear heater. This component utilizes the majority of the power available from the prime mover, and converts this energy into heat. The heater shears a heater fluid, typically glycol. This glycol is contained in a separate system, and may be heated by engine coolant, circulate through a heating hose, or to a liquid to air heat exchanger, or radiator, to provide warm air. 
         [0007]    Also connected to the drive of the prime mover is a centrifugal pump to move the glycol through the system. This system includes a heating hose, and reel for the heating hose. The hose may be extended from the unit to provide heat at equipment several feet from the heating unit. 
         [0008]    A fan, which may be driven by the prime mover, is utilized to move warm air through external ductwork to provide heat to equipment and/or personnel. 
         [0009]    The remaining major components to the system are heat exchangers. One heat exchanger is a liquid to liquid heat exchanger which transfers heat from the engine coolant to the heating glycol. The remainder of the heat exchangers may be liquid to air or liquid to liquid, depending on if more air heat is required or more glycol heat is required. On some specific engines, an intercooler air to air heat exchanger may also be present. 
         [0010]    Other system components include a fuel tank to operate the engine, a glycol reservoir, a trailer to house the components, and a control system to maintain operation of the system and alarm in the event of a mechanical failure. 
         [0011]    These and other objects of the invention, as well as many of the intended advantages thereof, will become more readily apparent when reference is made to the following description taken in conjunction with the accompanying drawing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The following drawings illustrate examples of various components of the invention disclosed herein, and are for illustrative purposes only. Other embodiments that are substantially similar can use other components that have a different appearance. 
           [0013]    The FIGURE schematically illustrates the production of heated glycol and/or heated air. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0014]    In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. 
         [0015]    Reference will now be made to the FIGURE for a more detailed description of the flameless glycol/air combination heater. A review of the components and then the process of the combination glycol and air heater will follow. 
         [0016]    The purpose of this invention is to provide either hot glycol or hot air, or both, in whatever proportion that the operator desires. This means that the operator can have most of the heat generated by this machine as hot glycol or as hot air or a combination of either by simply moving a lever. 
         [0017]    The first main component is the prime mover  10 , which can be either a diesel, gas, propane or natural gas fueled engine. A prototype and a second generation model have used an air cooled intercooler, but could have a glycol cooled intercooler or no intercooler at all. The prime mover also has glycol/engine coolant heat exchanger portions  60 ,  140  to keep the engine running within its ideal temperature range. 
         [0018]    Attached to the prime mover by a splined output shaft  12  is a dynamic heater  70 , which is a fluid shear heater. The majority of the engine horsepower is used to shear a heating fluid in the glycol heater, which in this case is an environmentally friendly glycol. The heating fluid can be any fluid that is practical to be used in an oilfield environment. It should be environmentally friendly as well as non-combustible and be commonly used in oilfield applications. Heating fluids used in this application include oil and glycol. 
         [0019]    The fluid shear heater  70  can use either metal plates moving across each other, spinning discs or pumping fluids through orifices to create fluid shear forces large enough to generate heat. The majority of the power generated by the engine is used for the purpose of shearing fluid to generate heat. The fluid shear heater is bolted directly to the engine and is powered by the splined output shaft  12  of the engine  10 . 
         [0020]    Between the engine and fluid shear heater is a torsional vibration dampener (not shown), which is used to smooth out the vibrations created by the prime mover  10 . The use of a torsional vibration dampener extends the life of the splined output shaft  12  and the fluid shear heater  70 . For the purpose of this application, glycol will be referred to as the heater fluid, but as mentioned before many other fluids could be used as well. 
         [0021]    A glycol pump  50  driven off of drive shaft  12  by shaft  54  is used to pump glycol heating fluid throughout the system. Pump  50  must be capable of pumping glycol at temperatures of up to approximately 200° F. (100° C.). 
         [0022]    Air/air intercooler  20  is a standard air to air intercooler as used in trucks and heavy machinery to cool compressed air from pipe  16  and return cooled air to engine  10  by pipe  18 . 
         [0023]    Radiator  30  is a standard radiator used in automotive applications. Radiator  30  is used to dissipate heat from glycol or similar fluids using air as the cooling medium. 
         [0024]    Exhaust heat exchanger  130  is an air to air heat exchanger. It is sized so that the incoming engine exhaust from pipeline  14  at up to 700° F. (400° C.) can be cooled down to 70° F. (20°-25° C.) and released by outlet  150 . 
         [0025]    Air fan  100  is a centrifugal fan sized for the amount of air required by the operator and to utilize the heat in the engine exhaust as moved through pipeline  14  to exhaust heat exchanger  130 . Cooled exhaust air is released through outlet  150 . Additional heated air is provided by intercooler  20  and radiator  30 . 
         [0026]    Glycol/air valve  80  is a variable control valve that is used to vary the amount of glycol passed between radiator  30  and glycol hose  90 . Glycol hose  90  is mounted on a reel that contains two lengths of hose, which are capable of transporting hot glycol. The reel allows the hoses to be uncoiled and moved to wherever they are needed. 
       The Heating Process 
       [0027]    Before starting the prime mover  10 , the operator should determine at what position the glycol/air valve  80  should be. The unit is then started and allowed to warm up to a predetermined temperature. The prime mover  10  is then sped up to maximum power and rpm. At this time, the fluid heater  70  starts to generate heat. 
         [0028]    There are four sources of heat in this process. The first source is the fluid heater  70 , the second is the intercooler  20 , the third is the engine coolant heat exchanger portions  60 ,  140  and the fourth is the engine exhaust heat exchanger  130 . 
         [0029]    The glycol to be heated is pumped from the glycol reservoir  40  along pipeline  42  to the glycol pump  50  and then along pipeline  52  to the engine coolant heat exchanger portion  60 . Heat is transferred at the engine coolant heat exchanger portion  140  from the hot engine coolant circulating therethrough to the glycol in exchanger portion  60 . The engine coolant is continuously pumped along pipelines  142 ,  144  by its own engine coolant pump for transfer of heat to heat exchanger portion  60 . 
         [0030]    The glycol is then pumped from this exchanger portion  60  to the fluid shear heater  70  along pipeline  62 , where the glycol is heated from the internal friction and shearing in the heater  70 . After leaving the fluid shear heater  70 , the glycol is pumped to the glycol/air valve  80  along pipeline  72 . The glycol is sent to either the glycol hose  90  by pipeline  82 , or to the radiator  30  by pipeline  84 , or a combination of both, depending on a position of a valve lever or a positioning of the valve  80  as selected by the operator. 
         [0031]    If 100% glycol is selected by the operator at the glycol/air valve  80  then all of the glycol will be directed to the hose  90  by pipeline  82  for release of heat shown at  120 . The cooled glycol is returned along pipeline  92  to the glycol reservoir  40 . The process to heat the glycol is then repeated. 
         [0032]    The only heat to be output as air will be from the intercooler  20 , the radiator  30  and the exhaust heat exchanger  130  moving in the direction of arrow  32 . Hot air is drawn off in the direction of arrow  32  by fan  100  (driven by shaft  102  off of drive shaft  12 ). Heated air is exhausted through external duct work in the direction of arrow  110 . 
         [0033]    If the operator selects 100% air on the glycol/air valve  80  then all of the glycol flow will be sent to the radiator  30  along pipeline  84 , resulting in all of the heat generated from the heated glycol to be output as heated air. The heated air is drawn off by fan  100  in the direction of arrow  32  to the duct  110 . The cooled glycol is returned to glycol reservoir  40  by pipe  34 . 
         [0034]    Any position other than the above two in the valve  80  will result in partial proportional flow to either the hose  90  or the radiator  30 . The amount of heated glycol compared to heated air is thereby controlled. 
         [0035]    The foregoing description should be considered as illustrative only of the principles of the invention. Since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and, accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.