Patent Publication Number: US-2011072845-A1

Title: Refrigerant injection device for refrigerant destruction facility

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims under 35 U.S.C. §119(a) the benefit of Korean Patent Application No. 10-2009-0091452 filed Sep. 28, 2009, the entire contents of which are incorporated herein by reference. 
     BACKGROUND 
     (a) Technical Field 
     The present disclosure relates to a refrigerant injection device for a refrigerant destruction facility. More particularly, it relates to a refrigerant injection device which is applicable to a refrigerant destruction facility using an incinerator such as a gasification melting system, a rotary Kiln furnace, a stocker furnace, etc. and a dedicated combustion furnace. 
     (b) Background Art 
     A refrigerant gas such as Freon is generically used in various refrigeration systems. When Freon is released into the air or atmosphere, it becomes an environmental pollutant as it destroys the ozone layer. Therefore, the use and discharge of Freon is regulated by laws. 
     The waste refrigerant that is produced during collection, recovery, and disposal typically includes chlorofluorocarbon (CFC) which is as an ozone-depleting substance, and hydrofluorocarbon (HFC), which is a global warming substance. 
     In general, more than 99.9% of refrigerant such as CFC and HFC is destroyed using an incinerator such as a gasification melting system, a rotary Kiln furnace, a stocker furnace, etc. or using a dedicated combustion furnace, which maintains the temperature above 800° C. with a retention time of more than 2 seconds. 
     There is shown in  FIG. 1  a refrigerant injection device used in combination with in an incinerator  18  used in Japan. The refrigerant injection device injects refrigerant into the incinerator  18  by increasing the evaporation rate of the refrigerant using a hot-water bath type vaporizer  10  and an external heating type heater  12  so the refrigerant is decomposed by a reaction with steam at a high temperature. 
     The refrigerant injection device includes a hot-water bath type vaporizer  10 , a valve  11 , a heater  12 , an oil filter  13 , a mist filter  14 , a flowmeter  15  and a metering valve  16 . The hot-water bath type vaporizer  10  vaporizes the refrigerant in a refrigerant container. The valve  11  is provided for selectively opening and closing the vaporizer  10 . The heater  12  is connected to the vaporizer  10  and heats the vaporized refrigerant to room temperature. The oil filter  13  and mist filter  14  are connected to the heater  12  and remove oil and mist. The flowmeter  15  and metering valve  16  are connected to the filters  13  and  14  and control the flow rate of refrigerant. 
     Such a refrigerant injection device includes an injection pipe  17  that is connected to the incinerator  18  so as to directly inject the refrigerant into the incinerator  18  and a cooler  19 . The cooler is provided to prevent the device from being damaged by the heat of the incinerator  18 . 
     Because the refrigerant is discharged from the refrigerant container without pressure control, the refrigerant injection device should increase the evaporation rate of refrigerant using the hot-water bath type vaporizer  10  and the heater  12  to improve the injection of the refrigerant into the incinerator  18 . 
     The vaporizer  10  vaporizes the refrigerant in the refrigerant container using hot water of 20 to 40° C. Alternatively, a hot-water spray type vaporizer or a hot blast heating type vaporizer is used for the hot-water bath type vaporizer  10  of  FIG. 1 . 
     The heater  12  is maintained at a temperature of 40 to 60° C. using an external heating coil. The heater  12  heats the vaporized refrigerant such that it is above room temperature. 
     Any oil or mist that may be in the refrigerant gas is/are removed from the refrigerant gas at a temperature above room temperature by the oil and mist filters  13 ,  14 . The flow rate of the refrigerant gas is controlled by the flowmeter  15  and the metering valve  16 . The refrigerant gas is injected into the incinerator  18  through the injection pipe  17 . Coolant having a temperature of 5 to 20° C. produced from the cooler  19 , circulates through the injection pipe  17 . As provided herein, this is done to prevent damage to the injection device by the heat of the incinerator  18 . 
     As the energy consumed by the vaporizer  10 , the heater  12 , and the cooler  19  is increased, the cost for treating the waste refrigerant is increased, and the space required for the vaporizer  10 , the heater  12 , and the cooler  19  also is increased. 
     In addition, when using the conventional refrigerant injection device having a single flowmeter  15 , it is difficult to precisely control the flow rate. Also, it is necessary to stop the injection of refrigerant during calibration of the flowmeter  15  and in the event of a failure in the flowmeter  15 . 
     The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
     SUMMARY OF THE DISCLOSURE 
     The present invention features a refrigerant injection device for a refrigerant destruction facility. Such a refrigerant injection device of the present invention advantageously reduces energy cost and installation space requirements of the device. In more particular embodiments, such a refrigerant injection device of the present invention includes a decompressor. As further described herein such a decompressor provides a mechanism by which the evaporation rate of refrigerant gas can be increased as compared to a conventional refrigerant injection device which employs a vaporizer, a heater, and a cooler which require large energy consumption. 
     In further embodiments, such a refrigerant injection device for a refrigerant destruction facility includes two flowmeters for measuring the flow rate of refrigerant. This arrangement provides a mechanism for precisely measure the flow rate of refrigerant thereby also providing a mechanism dor stably injecting the refrigerant into an incinerator of the refrigerant destruction facility. 
     According to another aspect of the present invention such a refrigerant injection device for a refrigerant destruction facility, includes a refrigerant container in which is stored refrigerant; a decompressor connected to the refrigerant container which is operated to decompress the refrigerant and thereby easily evaporated the refrigerant; and a flowmeter measuring the flow rate of the refrigerant as decompressed by the decompressor. 
     It is understood that the term “vehicle” or “vehicular” or other similar term as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g. fuels derived from resources other than petroleum). As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example both gasoline-powered and electric-powered vehicles. Other aspects and embodiments of the present invention are discussed below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features of the present invention will now be described in detail with reference to the following detailed description taken in conjunction with the accompanying drawing figures which are given hereinbelow by way of illustration only, and thus are not limitative of the present invention, wherein like reference characters denote corresponding parts throughout the several views and wherein: 
         FIG. 1  is a schematic diagram showing the configuration of a conventional refrigerant injection device for a refrigerant destruction facility. 
         FIG. 2  is a schematic diagram showing the configuration of a refrigerant injection device for a refrigerant destruction facility according to the present invention. 
         FIG. 3  is another schematic diagram provided to illustrate operation of the refrigerant injection device of  FIG. 2  during normal operation. 
         FIG. 4  is another schematic diagram provided to illustrate operation of the refrigerant injection device of  FIG. 2  during calibration of a first flowmeter. 
         FIG. 5  is another schematic diagram provided to illustrate operation of the refrigerant injection device of  FIG. 2  during calibration of a second flowmeter. 
     
    
    
     Reference numerals set forth in the drawing figures include reference to the following elements as further discussed below: 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 100: refrigerant container 
                 101: first valve 
               
               
                   
                 102: manometer 
                 110: decompressor 
               
               
                   
                 120: drain box 
                 121: first coolant line 
               
               
                   
                 122: second coolant line 
                 123: sampling port 
               
               
                   
                 130: oil filter 
                 131: mist filter 
               
               
                   
                 140: first flowmeter 
                 141: second valve 
               
               
                   
                 142: first bypass pipe 
                 143: bypass valve 
               
               
                   
                 150: second flowmeter 
                 151: third valve 
               
               
                   
                 152: second bypass pipe 
                 153: bypass valve 
               
               
                   
                 160: metering valve 
                 161: check valve 
               
               
                   
                 162: cut-off valve 
                 170: refrigerant destruction facility 
               
               
                   
                 171: injection pipe 
               
               
                   
                   
               
            
           
         
       
     
     It should be understood that the appended drawings are not necessarily to scale, present a somewhat simplified representation of various preferred features illustrative of the operation of the invention. Also, the specific features of the present invention as described herein, can include, for example, specific dimensions, orientations, locations, and shapes; however these are not intended to be limiting as these features will be determined by one skilled in the art in part by the particular intended application and use environment. 
     restart 
     DETAILED DESCRIPTION 
     Featured is a refrigerant injection device which is particularly suitable for use in a refrigerant destruction facility using an incinerator. Such an injection device includes a storage device which stores the refrigerant and a decompressor that is fluidly coupled to the storage device. The injection device further includes two flow meters and a cutoff-valve that are fluidly coupled to the decompressor. The cutoff valve is configured to cut off the injection of refrigerant. The injection device further includes bypass flow members that are fluidly coupled to the two flow meters. The bypass flow members and flow meters are configured and arranged to selectively measure the flow rate and to perform flow meter calibration without stopping the feeding of refrigerant to the injection device. 
     Hereinafter reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. While the invention will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention to those exemplary embodiments. On the contrary, the invention is intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
     Referring now to the various figures of the drawing wherein like reference characters refer to like parts, there is shown in  FIG. 2  a schematic diagram of a refrigerant injection device for a refrigerant destruction facility in accordance with the present invention. 
     Such a refrigerant injection device includes a refrigerant container  100 , a decompressor  110 , an oil filter  130 , a mist filter  131 , a plurality of flowmeters  140 ,  145 , and a metering valve  160 . 
     Refrigerant, such as that recovered from any of a number of articles known to those skilled in the art which utilize refrigerant, such as air conditioners, refrigerators, is stored in the refrigerant container  100 . Typically the refrigerant is stored under a high pressure such as for example, 5 to 10 kgf/cm 2 . Such a injection device also includes a first valve  101  that is fluidly coupled to the container  100  and is provided for opening and closing a refrigerant flow path of the refrigerant container  100 . In more particular embodiments, the first valve  101  is installed in piping on the top of the refrigerant container  100 . 
     In further embodiments, the injection device further includes a pressure gauge  102  that measures measure the pressure of the refrigerant being discharged from the refrigerant container  100 . Such a pressure gauge is any of a number of pressure gauges known to those skilled in the art and otherwise appropriate for the intended use. In a particular embodiment, the pressure gauge  102  is a manometer that is fluidly coupled to piping extending between and fluidly coupling the first valve  101  and the decompressor  110 . 
     The decompressor  110  is any of a number of decompressors known to those skilled in the art and otherwise appropriate for the intended use. [IS THERE AN EXAMPLE OF SUCH A DECOMPRESSOR??] In particular embodiments, the decompressor is configurable so that the refrigerant stored in the refrigerant container  100  evaporates responsive to the decompression action of the decompressor. In yet more particular embodiments, the decompressor is configured so as to increase the evaporation rate of the refrigerant as compared to conventional injection devices. 
     For example and in illustrative embodiments, the decompressor  110  is configured so as to be operable to reduce the pressure of the refrigerant from a high pressure (e.g., 5 to 10 kgf/cm 2 ) to a low pressure (e.g., 0 to 3 kgf/cm 2 ) such that the refrigerant in the refrigerant container  100  has an appropriate pressure (e.g., about 1.0 kgf/cm 2 ) whereby the refrigerant is injected into a refrigerant destruction facility  170 . 
     The oil filter  130  is fluidly connected to the decompressor  110  via a pipe and configured so as to remove oil contained in the refrigerant vaporized by the decompressor  110 . The mist filter  131  is fluidly connected to the oil filter  130  and is configured so as to remove impurities such as dust and foreign matter contained in the refrigerant from which oil is removed. In further embodiments, such an injection device further includes a drain box  120  for storing oil and mist filtered by the oil filter  130  and the mist filter  131 . Such a drain box is provided at the bottom of the oil and mist filters  130 , 131 . 
     In yet further embodiments, such an injection device further includes a sampling port  123  for analyzing the purity of the refrigerant being injected into the refrigerant destruction facility  170 . In more particular embodiments, the sampling port  123  is provided downstream of the mist filter, more particularly at the rear of the mist filter  131 . In yet more particular embodiments, a flexible hose is provided and connected to the sampling port  123  to facilitate the collection of a sample. 
     In yet further embodiments, another pressure gauge  102  or manometer is installed in the piping extending downstream of the filters  130 ,  131  (e.g., downsteam of the sampling port  123 . Such a pressure gauge is provided to measure the pressure of injected refrigerant and is used together when the decompressor  110  is controlled to provide an appropriate pressure at which the refrigerant is injected into the refrigerant destruction facility  170 . 
     The flowmeters  140 ,  145  and the metering valve  160  are arranged and configured so as to control the flow rate of the refrigerant in which oil and foreign matter are removed. In more particular embodiments, the injection device includes at least two flowmeters  140  and  150  that are connected in series. Also included at each of the flow meters  140 ,  150  are bypass pipes  142  and  152  and valves  141 ,  143 ,  151 , and  153 . The bypass pipes and vales are configured and arranged at each of the flowmeters  140  and  150  so refrigerant can be injected into the refrigerant destruction facility  170  in the case one of the flowmeters has failed or when a flowmeter is undergoing calibration. 
     In yet more particular embodiments, the injection device includes a first flowmeter  140  and a second flowmeter  150  that are connected in series. The second valves  141  are provided at the front and the rear of the first flowmeter  140 , and the third valves  151  are also provided at the front and the rear of the second flowmeter  150 . In addition, a first bypass pipe  142  and a second bypass pipe  152  are provided at the first flowmeter  140  and the second flowmeter  150 . The bypass pipes are particualry suitable for performing calibration of the first and second flowmeters  140  and  150 . 
     One end of the first bypass pipe  142  is connected between the second valve  141  at the upstream side and the pressure gauge  102  or manometer. The other end of the first bypass pipe  142  is connected between the second valve  141  at the downstream side and the third valve  151  at the upstream side such that the refrigerant, from which oil and dust are removed, is introduced into the second flowmeter  150 , without passing through the first flowmeter  140 . Also, a bypass valve  143  for opening and closing the pipe is installed in the first bypass pipe  142 . 
     One end of the second bypass pipe  152  is connected between the second valve  141  at the downstream side and the third valve  151  at the upstream side, and the other end of the second bypass pipe  152  is connected between the third valve  151  at the downstream side and the metering valve  160  such that the refrigerant measured by the first flowmeter  140  is introduced into the metering valve  160 , without passing through the second flowmeter  150 . Also, a bypass valve  153  for opening and closing the pipe is disposed in the second bypass pipe  152 . 
     In yet further embodiments, the injection device further includes a check valve  161  that is disposed in the pipe at the rear of the metering valve  160  to prevent the refrigerant, which is introduced into the refrigerant destruction facility  170 , from flowing backward. 
     In further embodiments, the injection device includes an injection pipe  171  that is provided at one side of the refrigerant destruction facility  170 , and a cut-off valve  162  is provided between the check valve  161  and the injection pipe  171 . The cut-off valve  162  provides a mechanism so as to rapidly cut off the flow rate of refrigerant in the event of an emergency of the refrigerant destruction facility  170 . 
     The refrigerant destruction facility  170  serves to decompose the refrigerant by allowing the refrigerant introduced through the injection pipe  171  to react with steam at a high temperature. 
     The operation and effect of the refrigerant injection device for the refrigerant destruction facility  170  in accordance with the present invention is discussed below. Reference shall be made to  FIG. 2  for functionalities of the refrigerant injection device not otherwise discussed below. 
     Typically, waste refrigerant is recovered from the place where it is produced or where it was being utilized in a container of 20 to 1,000 Kg by a refrigerant recovery machine. As the boiling point of the refrigerant such as CFC and HFC injected into the refrigerant injection device is less than −20° C., it is evaporated under atmospheric conditions. 
     Therefore, in the present invention, the pressure of refrigerant to be injected into the refrigerant destruction facility is reduced by the decompressor  110  and thereby evaporated. 
     The decompressor  110  reduces the pressure of refrigerant stored in the refrigerant container  100  from 5 to 10 kgf/cm 2  to 0 to 3 kgf/cm 2  such that the refrigerant in the refrigerant container  100  can be injected into the refrigerant destruction facility  170 . 
     As described herein, any oil and/or mist that is contained in the refrigerant (gas) at a temperature above room temperature and decompressed to a predetermined pressure by the decompressor  110 , are removed by the oil filter  130  and the mist filter  131 . Also, the flow rate of the refrigerant is controlled by the flowmeters  140 ,  150  and the metering valve  160 . Therrafter, the refrigerant gas is injected into the refrigerant destruction facility  170  through the injection pipe  171  and decomposed by the reaction with steam at a high temperature. 
     Thus and unlike the conventional refrigerant injection device which employs a vaporizer, a heater, and a cooler which require large energy consumption, when using the refrigerant injection device of the present invention, the refrigerant gas is evaporated by the decompressor  110 . In this way, it is possible to reduce the cost of energy consumed for treating the waste refrigerant and reduce the installation space of the device. 
     The refrigerant such as CFC and HFC is decomposed by the reaction with steam at a high temperature. 
     In general, more than 99.9% of refrigerant such as CFC and HFC is destroyed at a temperature above 800° C. for a retention time of more than 2 seconds. Hydrogen chloride (HCl) and hydrogen fluoride (HF) produced by the destruction of refrigerant are neutralized into CaCl 2  and CaF 2  by the addition of an alkaline reagent such as Ca(OH) 2  and then removed in post-treatment equipment of the refrigerant destruction facility as follows. 
     (1) Stabilization reaction of CFC-12 refrigerant: 
       2HCl+Ca(OH) 2 →CaCl 2 +2H 2 O
 
     (2) Stabilization reaction of HFC-134a refrigerant: 
       2HF+Ca(OH) 2 →CaF 2 +2H 2 O
 
     The refrigerant injection device for the refrigerant destruction facility in accordance with the present invention employs first and second flowmeters  140  and  150  connected in series. with such an arrangement, it is possible to increase the time of use and to precisely measure and accumulate the amount of refrigerant injected into the refrigerant destruction facility. 
     Referring now to  FIG. 3 , there is shown a schematic diagram illustrating operation of the refrigerant injection device for the refrigerant destruction facility in accordance with an embodiment of the present invention during normal operation. During normal operation, the bypass valves  143  and  153  of the first and second bypass pipes  142  and  152  that are connected to the first and second flowmeters  140  and  150  are closed. As a result, the refrigerant passing through the oil filter  130  and the mist filter  131  is injected into the refrigerant destruction facility  170  through the first and second flowmeters  140  and  150 . 
     In this embodiment, the first and second flowmeters  140  and  150  measure the flow rate of the refrigerant, respectively, to obtain a more precise flow rate by correcting the measurement values obtained by the two flowmeters  140  and  150 . 
     Referring now to  FIGS. 4 and 5 , there are shown schematic diagrams illustrating the operation of the refrigerant injection device during calibration of the first and second flowmeters. 
     Because an error can occur in the flowmeter when it is being used for a long time, it is typical practice to periodically calibrate the flowmeter. The calibration is done to correct the measurement value of the used flowmeter by comparing it with that of a reliable standard flowmeter. 
     Because conventional refrigerant injection device usually have a single flowmeter, it is necessary to stop operation of the device during calibration. In contrast, as the refrigerant injection device according to the present invention has the two flowmeters and two bypass pipes, the injection device can continue perform calibration without stopping operation of the injection device. 
     The calibration of the flowmeters according to the present invention is discussed below. 
     When the first flowmeter  140  is to be calibrated, as shown in  FIG. 4 , the second valves  141  disposed at the front and the rear of the first flowmeter  140  and the bypass valve  153  of the second bypass pipe  152  connected to the second flowmeter  150  are closed. The calibration is performed by comparing the measurement value of the first flowmeter  140  with that of a standard flowmeter. 
     The flow rate of the refrigerant gas, which passes through the bypass pipe  142  of the first flowmeter  140 , is measured by the second flowmeter  150 , and then the refrigerant gas is injected into the refrigerant destruction facility  170 . 
     When the second flowmeter  150  is to be calibrated, see  FIG. 5 , the third valves  151  disposed at the front and the rear of the second flowmeter  150  and the bypass valve  143  of the first bypass pipe  142  connected to the first flowmeter  140  are closed. The calibration is performed by comparing the measurement value of the second flowmeter  150  with that of the standard flowmeter. 
     Also, the flow rate of the refrigerant gas is measured by the first flowmeter  140 , and the refrigerant gas is injected into the refrigerant destruction facility  170  through the bypass pipe  152  of the second flowmeter  150 . 
     In  FIGS. 3 to 5 , the black symbols of the valves  141 ,  143 ,  151 , and  153  represent the closed state, and the white symbols of the valves  141 ,  143 ,  151 , and  153  represent the opened state. 
     During the calibration of the first flowmeter  140 , the refrigerant passes through the first bypass pipe  142  and is then injected into the refrigerant destruction facility  170  through the second flowmeter  150 . During the calibration of the second flowmeter  150 , the refrigerant passes through the first flowmeter  140  and is then injected into the refrigerant destruction facility  170  through the second bypass pipe  152 . Therefore, it is possible to perform the calibration of the flowmeter without stopping the operation of the device. 
     Moreover, in the event of a failure of one of the flowmeters  140  and  150 , the flow rate can be measured using the other flowmeter  140  or  150 , and when the two flowmeters  140  and  150  are connected in series, it is possible to reduce the margin of error to about 0.05%. 
     The refrigerant injection device for the refrigerant destruction facility  170  according to the present invention is usable for refrigerant destruction using the refrigerant destruction facility such as a gasification melting system, a rotary Kiln furnace, a stocker furnace, etc. 
     As described above, the refrigerant injection device for the refrigerant destruction facility according to the present invention has a number of advantages and advantageous effects such as: 
     1. Unlike the conventional refrigerant injection device which employs a vaporizer, a heater, and a cooler which require large energy consumption, for the refrigerant injection device of the present invention, the evaporation rate of refrigerant gas is increased comparatively by the use of the decompressor. Thus, it is possible to reduce the cost of energy consumed for treating the waste refrigerant and also reduce the installation space requirements for such a device. 
     2. Because the refrigerant injection device of the present invention employs two flowmeters, it is possible to more precisely measure and accumulate the amount of refrigerant injected into the refrigerant destruction facility through the correction between the flow rates measured by the two flowmeters, thus improving the accuracy about ten times that of the single flowmeter; and 
     3. It is possible to selectively measure the flow rate and perform the calibration without stopping the operation of the device through the two flowmeters and bypass pipes connected in series, and thereby it is possible to effectively use the device. 
     The invention has been described in detail with reference to preferred embodiments thereof. However, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.