Abstract:
A snow removal system ( 100 ) for melting snow into water includes a container ( 110 ) having a storage chamber ( 124 ) adapted to store snow and a predetermined amount of water ( 114 ). The snow removal system also includes a heating assembly ( 104 ) at least partially disposed in the storage chamber and adapted to heat water stored in the storage chamber to a selected temperature. The snow removal system further includes a mixing system ( 106 ) adapted to pressurize water and discharge the pressurized water through at least one nozzle ( 168 ). The nozzle is oriented to direct the pressurized water into the storage chamber. A method of snow removal whereby the snow removal system ( 100 ) is used to mix snow with heated water by spraying of pressurized water.

Description:
CROSS-REFERENCE TO A RELATED APPLICATION 
   This application claims the benefit of U.S. Provisional Patent Application No. 60/384,714, filed May 29, 2002, the disclosure of which is hereby expressly incorporated by reference and priority from the filing date of which is hereby claimed under 35 U.S.C. § 119. 

   FIELD OF THE INVENTION 
   The present invention relates to snow removal and more particularly, to snow removal systems for melting snow. 
   BACKGROUND OF THE INVENTION 
   Snow removal is a time consuming, labor intensive, and equipment intensive process. Accordingly, snow removal is a very expensive endeavor for communities of all sizes and populations, especially those communities located in northern tier states and provinces. The large equipment and labor costs involved in snow removal divert large portions of municipal, state, and Federal budgets and results in increased taxes. 
   Traditional methods of snow removal include plowing newly fallen snow into rows. The rows of snow are then either plowed to the side of the road or delivered to a dump site via graders, front-end loaders and dump trucks. This process is very time consuming, inefficient, and costly. In areas of dense housing, the difficulty of snow removal is significantly increased. For instance, with regard to the roads and parking lots serving high density areas typified by multi-family dwellings and commercial buildings, the snow removal vehicle must maneuver in relatively confined areas, which in turn requires a smaller sized and less efficient snow removal device. Further, the collected snow is often stored on site, eliminating the use of numerous parking stalls. 
   Some previously developed snow removal systems have attempted to address the problem of snow storage by melting the collected snow into water. Often the snow is loaded into a tank having a heating device disposed therein. The heat generated by the heating device is used to heat and convert the snow into a liquid having a fraction of the volume of the collected snow. The water is then disposed of, often by discharging the water to a storm drain. Although somewhat effective, previously developed snow removal systems are not without their problems. For instance, it has been found that the systems fail to mix the collected snow into the tank of heated water. This results in inefficiencies in the snow melting process, resulting in an increased rate of energy consumption and a decrease in the snow melting capacity of the snow removal system. 
   In some previously developed snow removal systems, a snow blower is attached to a duct. It has been discovered that under some conditions, such as when the temperature drops to near freezing or below, the duct of the snow blower can become clogged with snow, at least decreasing the efficiency of the snow blower and most often leading to the duct becoming fully obstructed, halting snow removal operations all together. 
   In other previously developed snow removal systems, the heat contained in a combustion heating source is discharged through an exhaust pipe. The exhaust pipe is not oriented to pass through the heated water, thus a significant amount of heat contained in the exhaust gases is discharged out the stack and not used for snow heating purposes. Thus, the thermal efficiency of the system is not maximized. 
   Thus, there exists a need for a snow removal system that is maneuverable, eliminates the need for snow storage, efficiently heats and mixes collected snow, is easily manufactured, reliable, inexpensive to manufacture and operate, and meets or exceeds the performance requirements of the end user. 
   SUMMARY OF THE INVENTION 
   One embodiment of a snow removal system formed in accordance with the present invention is provided. The snow removal system is operable to melt snow into water and includes a container having a storage chamber adapted to store snow and a predetermined amount of water. The snow removal system also includes a heating assembly at least partially disposed in the storage chamber and adapted to heat water stored in the storage chamber to a selected temperature. The snow removal system further includes a mixing system adapted to pressurize water and discharge the pressurized water through at least one nozzle, the nozzle oriented to direct the pressurized water into the storage chamber. 
   An alternate embodiment of a snow removal system formed in accordance with the present invention is provided. The snow removal system is adapted to collect and melt snow into water. The snow removal system includes snow collecting means for collecting snow from a ground surface and conveying the collected snow to a storage chamber adapted to store the collected snow and water produced from melted snow. The snow removal system also includes heating means at least partially disposed in the storage chamber for heating any contents of the storage chamber. The snow removal system further includes mixing means for mixing the contents of the storage chamber by discharging pressurized water into the storage chamber. 
   One method of snow removal performed in accordance with the present invention is provided. The method includes collecting snow from a ground surface and discharging the collected snow into a container containing heated water therein. The method also includes mixing the collected snow with the heated water in the container by discharging pressurized water into the container to mix the heated water and collected snow to assist in melting the collected snow. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing aspects and many of the attendant advantages of this invention will become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
       FIG. 1  is side elevation view of one embodiment of a snow removal system formed in accordance with the present invention wherein a container of the snow removal system is shown in cross-section to show a heating assembly and a mixing system disposed within the container; 
       FIG. 2  is a top planar view of the snow removal system of  FIG. 1 , wherein the heating assembly and other components have been removed for clarity; 
       FIG. 3  is a cross-sectional view of the snow removal system of  FIG. 1  taken substantially through Section  3 — 3  of  FIG. 1 ; and 
       FIG. 4  is a cross-sectional view of a duct of a snow collection system of the snow removal system depicted in  FIG. 1 , the cross-sectional cut taken substantially through Section  4 — 4  of FIG.  1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1-4  illustrate one embodiment of a snow removal system  100  formed in accordance with the present invention. Referring to  FIGS. 1-3 , the snow removal system  100  is designed to collect snow disposed upon a ground surface  112 , such as a road or parking lot, and melt the collected snow into water  114  occupying a fraction of the volume of the collected snow. The water may then be disposed of by discharge into a catch basin, tanker, reclamation system, ground surface, etc. 
   Generally described, the snow removal system  100  includes a snow collection system  102 , a heating assembly  104 , a mixing system  106 , a debris disposal device  108 , and a container  110 . The container  110  houses the heating assembly  104 , mixing system  106 , and debris disposal device  108 . Further, the container  110  stores the collected snow as it is melted and a selected amount of heated water  114 . The snow collection system  102  collects the snow from the ground surface  112  and deposits the collected snow into the container  110 . The heating assembly  104  heats and maintains the temperature of the water  114 . The mixing system  106  sprays a selected amount of the heated water  114  upon the snow discharged into the container  110  and into the heated water  114 . The sprayed water  115  assists in melting the snow through direct contact with the snow and by agitating the water  114  to promote mixing, resulting in the rapid conversion of the collected snow into water. As the container  110  fills, excess water is discharged from the container  110 . The container  110  may be formed from any rigid material, such as steel. 
   Focusing in greater detail upon the container  110 , the container  110  is a rectangular hollow block structure having four side walls  116 , a bottom surface  118 , and an open top  120 . The container  140  is adapted to couple to a vehicle  122 , such as a truck. Although the container  110  is depicted and described as being a hollow block structure, it should be apparent that the container  110  may be formed in any suitable manner, such as to have a rounded cross-section or to have a closed top surface in lieu of the open top  120 . 
   Further, although the container  110  in the illustrated embodiment of the present invention is depicted as coupled to the vehicle  122  and in communication with the snow collection system  102  coupled to the vehicle  122 , it should be apparent to those skilled in the art that the snow removal system  102  may be alternately formed. More specifically, it should be apparent to those skilled in the art that the container  110  may be adapted to be a stationary object, wherein the collected snow is deposited into the container  110  by a separate device, such as a front end loader or a dump truck (not shown). Further still, it should be apparent to those skilled in the art that the snow collection system  102  may be separated from the container  110  such that the container  110  is disposed upon a first vehicle or trailer and the snow collection system  102  is disposed upon a second vehicle that either tows the first vehicle or trailer or operates in proximity to the first vehicle or trailer, discharging collected snow into the container  110 . 
   The container  110  further includes a storage chamber  124 , the storage chamber  124  defined as the portion of the container  110  adapted to store collected snow and/or water. The volume of the container  110  is greater than the volume of the storage chamber  124  due to the presence of various components in the container  110  which are not adapted to receive collected snow and/or water  114 , most notably of which are portions of the heating assembly  104 . In the illustrated embodiment, the storage chamber  124  is adapted to hold 1,100 gallons at a selected minimum operating water level and is adapted to hold 2,800 gallons at a selected maximum operating water level. Therefore, the storage chamber  124  has a payload capacity of 1,700 gallons. 
   Disposed in the storage chamber  124  is a baffle assembly comprising four laterally oriented baffles  184 . The baffles  184  extend outward perpendicularly from the two longitudinally oriented side walls  116 . The baffles  184  terminate prior to reaching the centerline of the storage chamber  124  so as not to unduly inhibit mixing of the water  114 . The baffles  184  aid in the reduction of the free surface effect of the water  114  contained in the storage chamber  124 , especially during performance of braking and accelerating operations by the vehicle  122 . Although the illustrated embodiment depicts four baffles  184 , it should be apparent to those skilled in the art that other quantities of baffles are suitable for use with the present invention. 
   Focusing in greater detail upon the snow collection system  102 , the snow collection system  102  includes a well known snow blower  148  coupled to a conduit or duct  150 . The snow blower  148  of the illustrated embodiment is manufactured by Erskine Manufacturing, located in Erskine, Minn., model number 960FM. The snow blower  148  includes an upper auger  152  and a lower auger  154  disposed in a bucket  180 . The augers  152  and  154  are adapted to pulverize snow encountered by the augers. The snow blower  148  further includes an impeller (not shown) disposed in an impeller housing  156 . The impeller imparts a selected velocity to the snow pulverized by the augers  152  and  154  and directs the snow through the duct  150 . 
   The augers  152  and  154  and impeller (not shown) of the snow collection system  102  are powered by a well known hydraulic pump  155 . In the illustrated embodiment, the hydraulic pump is manufactured by Sauer-Sundstrand Co., located in Ames, Ind., Model No. SOR130HF1C80R3F1F03 GBA. Although the augers  152  and  154  and impeller are illustrated and described as powered from a hydraulic pump  155 , it should be apparent to those skilled in the art that the snow collection system  102  may be powered by any means currently known or to be developed. For instance, the snow collection system  102  may be powered by a well known Power Take-Off (PTO) device which would couple an engine of the vehicle  122  to the snow collection system  102  to power the snow collection system  102 . 
   Referring to  FIGS. 1-4 , the duct  150  has a first end coupled to the impeller housing  156  and a second end directed to discharge into the storage chamber  124 . The duct  150  passes on a lateral side of a cab  186  of the vehicle  122 . More specifically, the duct  150  does not pass over a roof of the cab  186  but passes to the right or left of the cab  186 . Preferably, the cab  186  is what is know in the industry as a half cab to better accommodate the passage of the duct  150  to the lateral side of the cab  186 . Further still, preferably the inner surface of the duct is lined with a coating or layer  188  exhibiting a low coefficient of friction relative to snow to aid in the reduction of snow accumulation in the duct  150 . In the illustrated embodiment, the layer  188  is formed from an ultra high density plastic (UHDP), or alternately an abrasive resistant urethane. 
   The duct  150  may include a gap  190  running longitudinally along a bottom surface  192  of the duct  150  between the opposite side walls of the duct  150 . The gap  190  aids in reducing the accumulation of snow upon the bottom surface  192  of the duct  150 . The momentum and velocity of the snow retains the snow in the duct  150  during normal operation. The gap  190  also permits air to enter the duct  150 . 
   The illustrated snow blower  148  is rated at 750 tons of snow per hour at 640 revolutions per minute (RPM). It is contemplated that enhanced operation may be obtained by increasing the RPM of the snow blower, such as to about 750 RPM, to aid in the conveyance of the snow through the duct  150 . 
   Although the illustrated embodiment depicts a duct  150  for assisting in the conveyance of snow from the impeller housing  156  to the storage chamber  124 , it should be apparent that alternate snow conveyance means may be employed, such as a conveyor belt (not shown). 
   Referring to  FIGS. 1-3 , and focusing in greater detail upon the heating assembly  104 , the heating assembly  104  includes a burner mechanism  126 , a combustion chamber  128 , a heat exchanger  130 , and an exhaust pipe  132 . The burner mechanism  126  may be any suitable heated gas generating device known in the art. In the illustrated embodiment, the burner mechanism  126  is a well known diesel fired burner manufactured by Hauck, located in Lebanon, Pa., model number BBO 1108. 
   The illustrated burner mechanism  126  is operable to generate 8 million British Thermal Units (BTUs) per hour through mixing and combusting diesel with air. Fuel consumption of the illustrated embodiment is estimated at approximately 20 to 35 gallons per hour. Inasmuch as design and operation of the burner mechanism  126  is well known, it shall not be described in further detail herein for the sake of brevity. As should be apparent to those skilled in the art, the rated thermal capacity of the burner mechanism  126  may be varied depending upon the design conditions of the snow removal system  100 . For instance, the rated thermal capacity is selected to provide a sufficient thermal output to melt a selected amount of snow per hour, usually measured in tons per hour, the snow having a selected temperature, using a heat exchanger  130  having a selected efficiency, and with a selected rate of heat loss to the outside environment. 
   A blower  194  is coupled to the burner mechanism  126  by a duct  196 . The blower  194  provides a suitable quantity of air for combustion. In the illustrated embodiment, the blower  194  is a turbo blower manufactured by Hauck located in Lebanon, Pa., Model-No. TBAB1-080-290-E-(1)CY. 
   The burner mechanism  126  discharges pressurized air and fuel into the combustion chamber  128 . The air and fuel mixture is combusted in the combustion chamber  126 , producing products of combustion  134  at an elevated temperature. The products of combustion flow through the heat exchanger  130 , wherein the heat contained in the products of combustion  134  is transferred to the water  114 . 
   Although the illustrated burner mechanism  126  is described as a diesel fuel source burner, it should be apparent to those skilled in the art that the burner mechanism  126  may be modified to accept alternate fuel sources, such as other hydrocarbon fuel sources, solid fuels sources, such as pulverized coal, etc. Further, although the illustrated embodiment is depicted with a single burner mechanism  126 , it should be apparent to those skilled in the art that multiple burner mechanisms are suitable for use and within the spirit and scope of the present invention. Further still, although a combustible heat source is depicted and described with relation to the illustrated embodiment, it should be apparent to those skilled in the art that alternate heat sources are suitable for use and within the spirit and scope of the present invention, such as electric heating coils, steam coils, etc. 
   The heat exchanger  130  includes a plurality of passageways including a primary fire tube  136  and an array of secondary fire tubes  138  disposed between two end plates  140   a  and  140   b . The diameter of the primary fire tube  136  is substantially larger than the diameter of the secondary fire tubes  138 . For instance, in the illustrated embodiment, the diameter of the primary fire tube  136  is 11 times greater than the diameter of the secondary fire tubes  138 . The gas flow capacity of the primary fire tube  136  is sized to substantially match the gas flow capacity of all of the secondary fire tubes  138  combined. The secondary fire tubes  138  are disposed about the primary fire tube  136 . 
   During normal operation, the products of combustion  134  exit the combustion chamber  128  as they pass through the primary fire tube  136  and into a first end chamber  142  of the heat exchanger  130 , the first end chamber  142  formed in part by the end plate  140 B. The products of combustion  134  change direction and enter the secondary fire tubes  138  from the first end chamber  142  and head towards the rear of the vehicle  122 . The products of combustion  134  are discharged from the secondary fire tubes  138  into a second end chamber  144  of the heat exchanger  130 , the second end chamber formed in part by the end plate  140 A. The products of combustion  134  are discharged from the second end chamber  144  through an exhaust pipe  132 . The exhaust pipe  132  passes horizontally through the storage chamber  124  for a selected length and then transitions to a vertical orientation, terminating at an exhaust tip  146  located outside of the container  110 . The outer surfaces of the primary fire tube  136 , secondary fire tubes  138 , and the exhaust pipe  132  are all in contact with the water  114  to promote heat transfer between the products of combustion  134  and the water  114 . 
   Although the heat exchanger  130  is depicted as a two-pass fire tube heat exchanger, it should be apparent to those skilled in the art that the heat exchanger may take many forms. For instance, it may be a single pass fire tube boiler or a water tube boiler. Or alternately, a plurality of primary fire tubes may replace the single primary fire tube  136  of the illustrated embodiment. 
   Focusing in greater detail upon the mixing system  106 , the mixing system  106  includes a fluid pressurization system  158  and a fluid delivery system  160 . The fluid pressurization system  158  includes a suction pipe  161  in fluid communication with the storage chamber  124  and an inlet of a pump  162 . An outlet of the pump  162  is coupled to a discharge pipe  164 . The pump  162  may be any well known pump now known or to be developed. In the illustrated embodiment, the pump is manufactured by Mission, located in Houston, Tex., Model No. 3-4R, Figure No. C5660, and Moduler No. 4605-90-30. In the illustrated embodiment, the pump  162  is adapted to discharge approximately 870 gallons per min (GPM) through an array of nozzles  168  at a pressure of about 18 psi. 
   The discharge pipe  164  is coupled in fluid communication with the fluid delivery system  160 . The fluid delivery system  160  includes a delivery pipe  166  coupling the array of nozzles  168  in communication with one another. The delivery pipe  166  is disposed near the perimeter of the open top  120  of the container  110 . The nozzles  168  are oriented to discharge pressurized water  115  into the storage chamber  124 . Preferably, the nozzles  168  are disposed above a selected normal operating water level of the water  114 , however, it should be apparent to those skilled in the art that the nozzles  168  may be disposed below the normal operating water level such that the tips of the nozzles  168  are submersed during normal operation. 
   Focusing in greater detail upon the debris disposal device  108 , the debris disposal device  108  includes a sloped bottom surface  118 . The sloped bottom surface  118  is inclined to direct debris that settles upon the bottom surface  118  to a channel  169  disposed longitudinally along the centerline of the bottom surface  118 . The sloped bottom surface  118  includes two side panels  170   a  and  170   b . Each side panel  170   a  and  170   b  is sloped laterally toward the channel  169 . The sloped bottom surface  118  further includes an end panel  172 . The end panel  172  is sloped in the longitudinal direction toward a proximal end of the channel  169 . 
   Disposed in the channel  169  is an auger  174 . The auger  174  may be rotated by any well known means such that debris present in the channel  169  is directed toward a debris discharge door  176  disposed at a distal end of the channel  169 . The debris discharge door  176  is pivotable between a closed position and an open position. In the closed position, the discharge door  176  substantially seals against the container  110  to impede water  114  and debris from discharging from the storage chamber  124 . In the open position, the discharge door  176  is pivoted away from the container  110  to permit water  114  to discharge through an aperture  178  in the container  110 . As the water  114  runs through the aperture  178 , the debris collected at the distal end of the channel  169  is suspended and carried out the aperture  178 . 
   In light of the above description of the structural components of the snow removal system  100 , the operation of the snow removal system  100  will now be described. Prior to snow removal, the storage chamber  124  is filled to a selected minimum operational water level such that at least the fire tubes  136  and  138  of the heat exchanger  130  are covered. In the illustrated embodiment, as mentioned above, the minimum operational water level is achieved when the 2,800 gallon storage chamber  124  contains 1,100 gallons. The burner mechanism  126  is utilized to burn a selected ratio of fuel and air in the combustion chamber  128 , producing products of combustion  134  having an elevated temperature. The products of combustion pass through the primary fire tube  136 , change direction and pass through the secondary fire tubes  138 . Thus, the products of combustion  134  pass twice through the water  114  contained in the storage tank  124 . 
   As the products of combustion  134  pass through the fire tubes  136  and  138  and the exhaust pipe  132 , the heat contained in the products of combustion  134  is transferred to the water  114 , heating the water  114  to a selected operating temperature. The selected operating temperature may range from 33 degrees Fahrenheit to 212 degrees Fahrenheit, with a preferred operating temperature of between about 50 degrees Fahrenheit to about 70 degrees Fahrenheit, with a more preferred operating temperature of 60 degrees Fahrenheit. 
   Once the water  114  is heated to operating temperature, or alternately before, the pump  162  is operated to circulate the water  114  contained in the storage chamber  124  through the nozzles  168 . The pressurized water  115  discharged through the nozzles  168  agitates and mixes the water  114  disposed in the storage chamber  124 . As the vehicle  122  moves forward, the bucket  180  scoops up snow disposed on the ground surface  112  and directs the snow into the augers  152  and  154 . The augers  152  and  154  pulverize the snow and direct the pulverized snow into the impeller housing  156 , wherein an impeller (not shown) imparts a high velocity to the collected snow, forcing the snow through the duct  150  and into the container  110 . 
   As the snow is discharged into the container  110 , the pressurized water  115  discharged from the nozzles  168  impacts the snow and water  114 , mixing the incoming snow rapidly with the heated water  114 . The mixing of the snow with the heated water  114  results in the rapid heating of the snow, removing the snow&#39;s latent heat of fusion to transform the snow from a solid to a liquid. The process continues until the storage chamber  124  reaches a maximum capacity, which in the illustrated embodiment is achieved when the water level reaches or nearly reaches the open top  120  of the container  110 . As stated above, the maximum capacity occurs when the storage container contains about 2,800 gallons of water  114 . 
   To discharge water  114  from the storage chamber  124 , either the discharge door  176  may be positioned in the open position or a drain port  182  in fluid communication with the storage chamber  124  may be opened. The discharge door  176  and/or drain port  182  may be positioned so as to discharge the excess water to a catch basin, ground surface, water reclamation system, etc., until the water level is brought back down to the minimum operating water level. The debris disposal device  108  may be operated on an as needed basis to remove debris from the storage chamber  124 . 
   As should be apparent to those skilled in the art, the illustrated embodiment may include an automatic control system (not shown) for controlling the operating parameters of the snow removal system  100  For instance, the automatic control system may include a water level sensor, high and low water sensors alarms, a water temperature sensor, high and low water temperature alarms, burner mechanism controls, water pressure sensor, high and low water pressure alarms, etc. Further, the automatic control system may include various additional controls to control the operation of the snow collection system  102 , heating assembly  104 , mixing system  106 , debris disposal device  108 , etc. Inasmuch as the design and operation of automatic control systems are well known in the art, the description of the automatic control system will not be described further herein. The control system used in one actual embodiment of the present invention was provided by Ponder Burner Company located in Washougal, Wash. 
   While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.