De-superheater for evaporative air conditioning

Information

  • Patent Grant
  • 6715312
  • Patent Number
    6,715,312
  • Date Filed
    Friday, October 25, 2002
    22 years ago
  • Date Issued
    Tuesday, April 6, 2004
    20 years ago
Abstract
An evaporative condensing air conditioning system employing a de-superheater and mist eliminator located between the air fan on an evaporative cooler and a spray tree that delivers water 20 as a coolant on the exterior surfaces of a condenser coil. The de-superheater receives superheated coolant gas from the compressor of the air conditioning system where air traveling on the outside of the de-superheater coil removes heat from the coolant gas located within the de-superheater coil to the point where the coolant is still a gas but is no longer superheated. The coolant gas then exits the de-superheater and flows into the evaporatively cooled condenser coil where the coolant is further cooled and condenses into a liquid before finishing the air conditioning circuit by consecutively moving through an optional coolant receiving chamber, a thermal expansion valve, an evaporator, and returning to the compressor.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to an evaporative condensing air conditioning system employing a de-superheater and mist eliminator located between the air fan on an evaporative cooler and a spray tree that delivers water as a coolant on the exterior surfaces of a condenser coil. The de-superheater receives superheated coolant gas from the compressor of the air conditioning system where air traveling on the outside of the de-superheater coil removes heat from the coolant gas located within the de-superheater coil to the point where the coolant is still a gas but is no longer superheated. The coolant gas then exits the de-superheater and flows into the evaporatively cooled condenser coil where the coolant is further cooled and condenses into a liquid before finishing the normal air conditioning circuit.




2. Description of the Related Art




Currently in evaporatively cooled air conditioning units, superheated coolant gas flows from the unit's compressor directly to an evaporatively cooled condenser coil. Because the coolant gas is superheated when it enters the condenser coil, it causes the water that flows downward over the exterior surfaces of the condenser coil to be boiled off of the coil where the coolant enters the condenser coil, leaving behind mineral deposits and scale on the exterior of the condenser coil in this area that are similar to the water deposits that are formed in a tea kettle when the water in the tea kettle boils away. These deposits and scale greatly decrease the heat exchange capacity of the condenser coil and decrease the useful life of the condenser coil because the decreased cooling efficiency of the coil will eventually dictate that the coil be replaced.




The present invention addresses this problem by removing the superheat from the hot coolant gas before the gas reaches the evaporatively cooled condenser coil. More specifically, the present invention employs an air cooled de-superheater and mist eliminator located between a spray tree that delivers water to the exterior surfaces of the condenser coil and the air fan that normally pulls air through the condenser but now also pulls air through the de-superheater coil ,is a means of cooling the superheated coolant gas that flows through the de-superheater coil.




The hot coolant gas from the compressor first flows through the de-superheater where the superheat is removed from the coolant via air cooling. The coolant stream leaving the de-superheater is a saturated gas. This coolant stream enters the condenser coil at a temperature that significantly reduces the possibility of mineral build up and scaling on the exterior surfaces of the evaporatively cooled condenser coil and is further cooled in the condenser. When the coolant condenses within the condenser coil it becomes a saturated liquid. From the condenser coil, the coolant flows through the normal air conditioning circuit by consecutively moving through an optional coolant receiving chamber, a thermal expansion valve, an evaporator, and returning to the compressor.




The present invention includes a mist eliminator that is physically located between the de-superheater and the water spray tree to prevent droplets of water from reaching the de-superheater from the spray tree, thereby preventing mineral build up and scale from being deposited on the exterior surfaces of the air cooled de-superheater coil.




In reducing the amount of cooling water that turns into water vapor at the condenser and leaves the unit via the air flow through the air fan, the amount of make up water for the evaporative cooling system is reduced, thereby saving water costs. Also, with less evaporation of the cooling water, water treatment costs are also reduced because less chemical treatment is needed to keep the cooling water in balance so that it will not scale up or corrode in the cooling water circuit. The cooling water circuit consists of the spray tree, the exterior surface of the condenser coil, a water sump, and a water line that connects the water sump and the spray tree.




The present invention not only increases the efficiency and life of the condenser by preventing mineral deposits and scale from forming on the exterior surface of the condenser coil, it also increases the cooling capacity of the condenser because the condenser does not have to remove the superheat from the coolant. This makes the unit operate more efficiently.




SUMMARY OF THE INVENTION




The present invention is an evaporative condensing air conditioning system employing a de-superheater for removing the superheat from the hot coolant gas before the gas reaches the evaporatively cooled condenser coil. More specifically, the present invention employs an air cooled de-superheater and mist eliminator located between a spray tree that delivers water to the exterior surfaces of the condenser coil and an air fan that normally pulls air through the condenser, but in the present invention also pulls air through the de-superheater coil as a means of cooling the superheated coolant that flows through the de-superheater coil.




The hot coolant gas from the compressor first flows through the de-superheater where the superheat is removed from the coolant via air cooling. Then the coolant leaving the de-superheater enters the condenser coil at a temperature that significantly reduces the possibility of mineral build up and scaling on the exterior surfaces of the evaporatively cooled condenser coil. The coolant is further cooled and condenses into a liquid within the condenser coil before finishing the air conditioning circuit by consecutively moving through an optional coolant receiving chamber, a thermal expansion valve, an evaporator, and returning to the compressor.




The present invention also includes a mist eliminator that is physically provided between the de-superheater and the water spray tree to prevent stray droplets of water from reaching the de-superheater from the spray tree, thereby preventing mineral build up and scale from being deposited on the exterior surfaces of the air cooled de-superheater coil.




The cooling water circuit consists of the spray tree, the exterior surface of the condenser coil, a water sump, and a water line that connects the water sump and the spray tree.




The spray tree sprays cooling water on the exterior surface of the condenser coil. Heat from the hot coolant located within the condenser coil is transferred to the cooling water on the exterior surface of the condenser coil, causing part of the cooling water to be vaporized into the air and thereby removing the heat from the unit with the air that is pulled through the condenser, the mist eliminator and the de-superheater by the air fan. The water sump receives the cooling water that drips off of the condenser coil and the water is continuously pumped through the water line back to the spray tree from the sump. Water is replaced in the sump by a makeup water connection. The amount of makeup water is reduced by use of the de-superheater.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a diagram showing a de-superheater for evaporative condensing air conditioning constructed in accordance with a preferred embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




The Invention




Referring now to

FIG. 1

, there is illustrated an evaporative condensing air conditioning system


10


employing a de-superheater


12


for removing the superheat from hot coolant gas before the gas reaches the evaporatively cooled condenser


14


constructed in accordance with a preferred embodiment of the present invention. The system


10


employs the air cooled de-superheater


12


and mist eliminator


16


that are located between a spray tree


18


that delivers cooling water


20


to the exterior surfaces of the condenser coil


14


and an air fan


22


that normally pulls air through the condenser


14


, but in the present invention also pulls air through the mist eliminator


16


and the de-superheater coil


12


as a means of cooling the superheated coolant that flows through the de-superheater coil


12


.




Superheated hot coolant gas from a compressor


24


first flows through coolant line


26


to the de-superheater


12


where the superheat is removed from the coolant via air cooling. Then the coolant leaving the de-superheater


12


travels via coolant line


28


to the condenser


14


, entering the condenser coil


14


as a saturated gas and at a temperature that does not promote mineral build up and scaling on the exterior surfaces of the evaporatively cooled condenser coil


14


. The coolant is further cooled and condenses into a liquid within the condenser coil


14


before finishing the air conditioning circuit by consecutively moving through a coolant line


30


to an optional coolant receiving chamber


32


, through another coolant line


34


to a thermal expansion valve


36


, through still another coolant line


37


to an evaporator


38


, through the evaporator


38


, and returning to the compressor


24


via still another coolant line


40


. Although the air conditioning circuit is described as having a coolant receiving chamber


32


, the feature is optional. As shown in the drawing by arrows F and G, an air handling fan


41


forces air to be cooled over the chilled exterior surfaces of the evaporator coil


38


in order to provide cool air for use in a building. Although the air handling fan


41


is shown in the drawing as being located upstream of the evaporator


38


so that it pushes air through the evaporator


38


, it could also be located downstream of the evaporator


38


so that it pulls air through the evaporator


38


.




The present invention also includes a mist eliminator


16


that is physically provided between the de-superheater


12


and the water spray tree


18


to prevent stray droplets of water


20


from reaching the de-superheater


12


from the spray tree


18


, thereby preventing mineral build up and scale from being deposited on the exterior surfaces of the air cooled de-superheater coil


12


.




The cooling water circuit consists of the spray tree


18


, the exterior surfaces of the condenser coil


14


, a water sump


42


, a water line


43


that connects the water sump


42


, and a water pump


44


that continuously pumps cooling water


20


via a water line


46


from the water sump


42


to the spray tree


18


. Water


20


is replaced in the sump


42


by a makeup water connection


47


. The amount of makeup water is reduced by use of the de-superheater


12


.




The spray tree


18


sprays cooling water


20


on the exterior surface of the condenser coil


14


. Heat from the hot coolant located within the condenser coil


14


is transferred to the cooling water


20


on the exterior surface of the condenser coil


14


, causing part of the cooling water


20


to be vaporized into the air and thereby removing the heat from the unit


10


with the air that is pulled by the air fan


22


through the air circuit of the evaporative cooler, i.e. through the condenser


14


, then through the mist eliminator


16


, and finally through the de-superheater


12


, as shown by arrows A, B, C, D, and E. The water sump


42


receives the cooling water


20


that drips off of the condenser coil


14


, and the water pump


44


continuously pumps cooling water


20


through the water line


46


back to the spray tree


18


from the sump


42


.




While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for the purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled.



Claims
  • 1. A de-superheater for an evaporative condensing air conditioning system comprising:an air cooled de-superheater coil, said de-superheater coil connected to and receiving superheated coolant gas from a compressor of an evaporative condensing air conditioning system, and said de-superheater coil provided with one connection to and supplying completely de-superheated coolant gas to an evaporatively cooled condenser coil of the evaporative condensing air conditioning system.
  • 2. A de-superheater for an evaporative condensing air conditioning system according to claim 1 further comprising:a mist eliminator located between the de-superheater coil and a spray tree of the evaporative condensing air conditioning system to prevent water droplets from the spray tree from reaching the de-superheater coil.
  • 3. An evaporative condensing air conditioning system with de-superheater according to claim 1 further comprising:said condenser coil connected to and supplying liquid coolant gas to a thermal expansion valve, said thermal expansion valve connected to and supplying coolant gas to an evaporator, and said evaporator connected to and supplying coolant gas to said compressor.
  • 4. An evaporative condensing air conditioning system with de-superheater according to claim 3 further comprising:a mist eliminator located between the de-superheater coil and a spray tree of the evaporative condensing air conditioning system to prevent water droplets from the spray tree from reaching the de-superheater coil.
  • 5. An evaporative condensing air conditioning system with de-superheater according to claim 1 further comprising:a common air supply passing through both the evaporatively cooled condenser coil and the de-superheater coil.
  • 6. An evaporative condensing air conditioning system with de-superheater according to claim 5 further comprising:a mist eliminator located between the de-superheater coil and a spray tree of the evaporative condensing air conditioning system to prevent water droplets from the spray tree from reaching the de-superheater coil.
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Number Name Date Kind
4311498 Miller Jan 1982 A
4796437 James Jan 1989 A
5411078 Ares May 1995 A
5692387 Alsenz et al. Dec 1997 A
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5816318 Carter Oct 1998 A
6343479 Merritt Feb 2002 B1
6422035 Phillippe Jul 2002 B1
20010027664 Ross Oct 2001 A1