Abstract:
A vaporization-condensation process using the refrigerant cycle (heat pump) for energy recycling between the vaporization and condensation processes with the refrigerant heat absorption/rejection capacity maximized to minimize installed power by controlling the system operating pressure (absolute) and allowing for the recovery of the condensable liquid vaporized, directly, indirectly, and within the seal liquid of the liquid ring pump if included in the system to; provide the less costly operating system feasible, recover one liquid from another, remove a liquid or liquids from a solid, purify water and, eliminate or minimize gas admission to the environment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
         [0001]    Not Applicable  
         STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0002]    Not Applicable  
         REFERENCE TO MICROFICHE APPENDIX  
         [0003]    Not Applicable  
         BACKGROUND OF THE INVENTION  
         [0004]    This invention relates to the areas of waste reduction, material recovery, and water production-purification through the removal of a liquid or liquids from a mixture of liquids, or the removal of a liquid or liquids mixed with a solid or solids, or for the separation of pure water from an impure source. Many processes produce by-products that contain elements or materials that are re-usable and need separation from unwanted materials. Separating useable material or safe material from the by-product can reduce waste disposal cost by reducing volume and weight. Such a removal process can also increase the economic value of the end product allowing for a reduction in the use of virgin material.  
           [0005]    For example, sewage plant waste can be disposed of more economically by reducing weight and resultant transport costs through drying. Similarly, sawdust or other wood waste can be transported less costly and being dried has a higher heat value for use as a fuel. Solvents used for cleaning can be separated from the waste material gained during the cleaning process. Water or other condensable products can be removed from petroleum products such as oil.  
           [0006]    The natural supply of safe drinking or other forms of pure water is decreasing resulting in the ever increase consumption of bottled or filter water. Water distillation using this invention is another example of its use and requirement.  
           [0007]    Existing separation processes provide a heat source to heat the material and vaporize the liquid to be separated and if the resultant gas vapor is to be recovered a separated cooling source to remove the required heat of condensation. This method is not energy efficient as the heat required for the process is not recovered resulting in a higher energy consumption rate than necessary and if fossil fuels are the energy source increased atmospheric emissions. This invention (process) offers a closed loop energy recovery system at optimal operating conditions to minimize the generation of energy, minimize the required atmospheric emissions associated with energy generation, minimize the discharge of undesirable gas to the environment and, in most cases, a reduction in operating costs.  
         BRIEF SUMMARY OF THE INVENTION  
         [0008]    This invention provides a process for the separation and recover of a liquid or liquids from a mixture of material (solid or liquid) with recycled energy by capturing the heat energy associated with the condensing the gas generated during the heating process, and utilizing this energy plus the energy generated or absorbed by the other system components as the heating source thereby recycling the energy and significantly reducing energy generation, environmental emissions, and associated costs. The invention provides control of the system operating pressure (absolute) thereby maximizing compressor heat absorption and transfer capacity providing the highest feasible Coefficient of Performance for the liquid or liquids to be removed.  
           [0009]    It is therefore an object of the present invention to provide a heat pump for the removal of a liquid(s) from another liquid(s) or solid(s) through the process of vaporization and condensation with the heat pump performance (capacity) optimized for the liquid to be removed and recovered and provide an optional method of minimizing any unwanted discharge of gas and or liquid to the environment. The heat pump system can be provided for single or multi-stage process, with either single or multi-stage energy capture or recycling.  
           [0010]    Another object of the invention is to provide stable operation for the compressor of the heat pump system by providing secondary heat transfer loops, one each for the evaporator and condenser elements of the heat pump system. Said heat transfer loops will have liquid storage capacity for heat sinks and the means to absorb additional energy or discharge from the process excess energy. The heat sink capacity of the system minimizes operating temperature changes and the rate of any change at both the compressor heat rejection and absorption elements. The heat is also available for use each time the system to process the material. For water distillation the secondary loops may be eliminated if desired to minimize system costs.  
           [0011]    A further object of the invention is maximizing the ratio of heat absorbed to compressor input power by controlling the system operating pressure for at the vaporization and condensation processes. Such controls allows for the smallest temperature difference between the compressor inlet and outlet temperatures.  
           [0012]    The invention further provides a method for direct contact or indirect liquid recovery and storage with the aspect of storage providing chilled liquid storage and heat sink for consistent and stable compressor return gas temperature. This facilitates material separation and recovery reducing or eliminating atmospheric discharge of gases. For water purification this secondary loop cold sink may be eliminated if necessary to minimize system costs.  
           [0013]    A further object of the invention is to provide the minimum operating cost through energy recycling by using the heat absorbed by the heat pump as the means for heating the material to be processed. much of its heat to the liquid in the secondary loop  12  condensing the refrigerant to a liquid that passes through the liquid filter  25 , control solenoid valve  26 , and sight glass  27  to the thermal expansion valve (TX valve)  28 . The secondary loop  12  is used to heat the material in the process chamber  14 .  
           [0014]    The TX valve  28  allows liquid refrigerant under pressure to expand into the evaporative element of the evaporator  29  with the flow rate controlled by the exit temperature sensor. The refrigerant liquid vaporizes to refrigerant vapor picking up heat from the secondary cooling loop  13  from its liquid passing through the evaporator  29  and, as a low temperature gas, is returned to the refrigerant compressor  10 . This heat removal provides the secondary loop  13  with a liquid sufficiently cold to cause condensation in the recovery chamber  15  and recovers the energy of condensation and, if so provided, the heat energy resulting from the operation of the liquid ring pump  16 . As illustrated, the liquid ring pump  16  seal liquid is the same liquid that is circulated in the secondary loop  13 ; however, optionally it could be a separate loop cooled separately or the same loop cooled separately.  
           [0015]    The secondary liquid loop  12  for heat transfer to the process chamber  14  consists of the condenser  24 , flow-splitting valve  36 , auxiliary heat exchanger  32 , process chamber heating element  33 , optional liquid storage volume  34 , and a circulating pump  35 . All of the rejection heat from the refrigerant loop  11  is transferred to the secondary heating loop  12 . The flow-splitting valve  36  is used to divert liquid to the auxiliary heat exchanger  32  for the removal of excess heat energy with said heat exchanger available as air to liquid or liquid-to-liquid type. The optional liquid storage  34  volume provides energy storage for use at the start of the process and provides a heat sink to slow the rate of change and amount of change in operating temperature providing a stable temperature range for the condenser  24  operation.  
           [0016]    The process chamber  14  may be a single container that is manually or automatically filled with a mixture of liquids or liquids with a solid or solids. Illustrated in FIG. 1 is the automatic feed of liquids from a batch container  30  though a float valve  31 , solenoid valve  37  into chamber  14  with connection to sight glass  40  and vapor mist  
           [0017]    A further object of the invention is maximizing the recovery of condensable gases that should not be discharged to atmosphere by accumulating and removing the gas or gases in its liquid state.  
           [0018]    Another object of the invention is a simplified method of water distillation operating at a vacuum using energy recycling without secondary heat loops and or mechanical operating pressure control. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0019]    [0019]FIG. 1 is a schematic circuit diagram of the heat pump system with secondary loops, with block indications for the process chamber, recovery chamber, and liquid ring pump system according to the invention.  
         [0020]    [0020]FIG. 2 is a schematic circuit diagram for a simplified water distillations system according to the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]    The invention provides a new process utilizing a heat pump with or without secondary heating or cooling loops for capturing the heat of condensation and recycling this heat, a means to discharge excess heat, a chamber or chambers for the material being processed with a means for feeding/filling it, a chamber for the recovery of the material to be removed from the processed material with a means to remove it, and an absolute pressure control system.  
         [0022]    The invention as illustrated in FIG. 1 includes a heat pump system  10  with secondary heat transfer loops  12  &amp;  13 ; typical material processing chamber  14 , typical recovery chamber  15 , and liquid ring pump  16 .  
         [0023]    The primary refrigerant loop  11  incorporates conventional refrigeration cycle or heat pump cycle components including compressor  10 , primary condenser  24 , and evaporator  29 . The compressor pressurizes the refrigerant vapor of a refrigerant such as, for example, R 22 . At the primary condenser  24 , the compressed hot vapor gives up separator  42  of feeding line  19 . The heating element  33  of the secondary heating loop heats the contents of chamber  14  causing the liquid or liquids within the chamber to vaporize in accordance with their vapor pressure characteristics. The resultant vapor passes through the vapor mist separator  42  with the mist or liquid separated and returning to the chamber via the slight glass  40 . The vapor mist separator is connected to the recovery chamber  15  by line  20 . The sight glass  40  contains a float that opens and closes the high level switch  41 . This high level switch controls solenoid valve  37  and maintains the chamber full until float valve  31  closes blocking the feed to the system. This float closes when all the liquid in chamber  30  has been transferred to chamber  14 .  
         [0024]    For blow-down or cleaning purposes of the process chamber  14 , manual or automatic valve  38  allows draining the contents to drain  39 . Air or other form of pressure can be applied at entrance  44  though valve  43  with valve  45  closed to isolated the process chamber. Such cleaning can be automated or manual.  
         [0025]    The vapor generated in the process chamber  14  is drawn into the recovery chamber  15 , as the operating pressure of the recovery chamber  15  is less than the vapor pressure generated. Recovery chamber  15  is designed to operate at an absolute pressure to allow for condensation at a low temperature. In order for the liquid in the process chamber  14  to vaporize, it needs to have its temperature increased only above the temperature of condensation achieved by the absolute pressure in the recovery chamber  15 . This temperature pressure relationship between the two chambers offers the ability to maximize the heat absorption capacity and resultant Coefficient of Performance of the heat pump system by allowing for a compressor suction temperature close to the compressor discharge temperature at a lower discharge temperature than operations at atmospheric conditions.  
         [0026]    The vapor from the process chamber  14  is condensed in the recovery chamber  15  by the direct cooling action of the liquid spray  46 . Optionally, not shown, condensation can occur indirectly by using a cooling element or some other form of heat exchanger within the chamber.  
         [0027]    The initial vacuum and removal of non-condensable gas from the process chamber  14  and recovery chamber  15  is achieve by the liquid ring pump  16  though a connection line  21  to the recovery chamber  15  including a valve  55  and check valve  56 . Valve  56  is available to isolate the liquid ring pump  16  from the chamber if the recovery chamber needs to be pressurized through entrance  44 , valve  43  and valve  45 . In this illustration the seal liquid for the liquid ring pump  16  is the same liquid that is sprayed and is delivered to the liquid ring pump though line  18  and valve  52 . The non-condensable gas and liquid exit the liquid ring pump  16  to the liquid gas separator  54  with the gas exhausted at  22  and the liquid returning through line  18  and valve  53  to a liquid storage tank  17 . Valves  53  and  52  are used to isolate the system pressure (absolute) from the liquid ring pump  16  when the pump is not operating. Once the desired absolute pressure is achieved by the liquid ring pump  16 , it is stopped and only turns on to remove any additional non-condensable gases that increase the pressure and are sensed by electrical pressure gauge  47 .  
         [0028]    Condensable gases drawn from the recovery chamber  15  will be condensed in the seal of the liquid ring pump  16  and returned to the liquid storage  17 . The energy used to drive the liquid ring pump is seen as a temperature increase in the seal liquid and it as well as any heat of condensation is return for capture and re-use through line  18   
         [0029]    The condensation and spray liquid of the recovery chamber  15  accumulates with the seal liquid (when the pump is in operation) in the storage chamber  17  with high and low level control sensor  48 . This liquid is pumped continuously during operation through the secondary loop  13  by the pump  49 . The level control sensor  48  opens solenoid valve  50  allowing the excess condensate to be sent to drain or to a storage container located at  51 . The storage capacity of the storage chamber  17  provides for a source of heat for the heat pump evaporator  29  and operates as a energy sink to minimize temperature changes and the rates at which temperature may change providing for a consistent return gas temperature and smooth operation of the heat pump.  
         [0030]    Options to the configuration of FIG. 1 include:  
         [0031]    A. A separate liquid ring seal water loop cooled by the heat pump.  
         [0032]    B. An air jet using the vapor to be recovered as its motive gas and drawing a vacuum on the recovery chamber to allow for very low operating pressures.  
         [0033]    C. The use of indirect cooling in the recovery chamber though an appropriate heat exchanger.  
         [0034]    D. Combining the elements of recovery and liquid storage into one vessel.  
         [0035]    E. Use of a seal liquid different from the liquid being recovered.  
         [0036]    This invention as illustrated in FIG. 2 provides a simplified system for water or other liquid purification without secondary liquid loops and or the liquid ring pump utilized in FIG. 1. Such a process or machine may be single or multistage with each stage consisting of a heat pump circuit (evaporator and condenser), process chambers, recovery chambers, a filling method and a discharge method.  
         [0037]    As illustrated the compressor  10  pumps hot refrigerant gas to the heating element (condenser)  24  of the process chamber  14  where the gas condenses to a liquid giving up most of its heat energy to the liquid being processed. The hot liquid refrigerant passes through a pressure-flow control element  57  into the cooling element (evaporator)  29  of the vapor recovery chamber  15 . The pressure-flow control element may be as simple as a capillary tube or tubes or as complex as a TX valve. The hot liquid expands vaporizing to a refrigerant gas in the cooling element (evaporator)  29  and returns to the inlet of the compressor  10  via a liquid vapor-separating receiver  58 .  
         [0038]    The process chamber  14  can be manually filled with the liquid or automatically as shown though solenoid valve  37  with an inlet supply line. The outlet of solenoid valve  37  is to the bottom of the process chamber  14  or to the top of the process chamber  14  via a sight glass  40  for level indication and level control and vapor-mist separator  42 . The sight glass  40  includes a float to operate the high-level  41  and low-level  60  sensors. This process chamber  14  also has a direct heater  59  and is connect at its top through the vapor-mist separator to the top of the recovery chamber  15 .  
         [0039]    The recovery chamber  15  includes a discharge tube  67  that extends to the bottom most level of the chamber with an exit into a directional control valve  61  or other form of check valve. The directional control valve  61  is connected to a second such valve  62  though a temperature sensor  63 . An exhaust  64  and delivery tube  65  are connected to the directional control valve  62 .  
         [0040]    In operation the first filling of the liquid is through solenoid valve  37  into the process chamber  14  until the solenoid valve  37  is closed by the high level sensor  41 . During filling and operation the drain solenoid valve  38  is closed blocking drain  39 . At indication of being full by high-level sensor  41  heating element  59  is powered heating the liquid in the process chamber to above 212 degree F. sanitizing the liquid and creating steam. The steam will pass through the vapor-mist separator  42  where the mist is separated and dropped into the sight glass  40  for return. The vapor travels into the top of the recovery chamber  15  where being lighter than air displaces the air (non-condensable gases) out of the recover chamber  15  through the discharge tube  67 , direction control valves  61  and  62 . The steam will exit the system at the exhaust  64  as the directional control valve  62  blocks (prevents) gas from passing into delivery tube  65  where only liquid is allowed. Heater  59  is operated until the temperature sensor  63  reaches a preset temperature indicating that all non-condensable gas has been removed from the both chambers.  
         [0041]    The temperature sensor  63  also initiates operation of the heat pump system  10 . With the hot refrigerant liquid expanding into a gas at the cooling element  29  (evaporator) the energy in the steam is removed condensing it and creating a vacuum in the recovery chamber  15  and process chamber  14 . The recovery chamber  15  is isolated from the atmosphere by the direction control valve  61 . The energy heat recovered at the cooling element  29  into the refrigerant is returned to the system along with the heat energy of the compressor  10  power at the heating element  24  (condenser) in the process chamber  14 .  
         [0042]    As a vacuum was established by the condensation of the steam in the system the heat pump  10  is allowed to operate at temperatures well below those required at atmospheric pressure to vaporize the liquid and at a lower temperature difference between the compressor inlet and discharge temperatures. This allows for the highest possible compressor Coefficient of Performance.  
         [0043]    When all the liquid has been vaporized from the process chamber  14  the process is stopped by the low level sensor  60 . At this point the next batch or continuation of the system can be automatic or manual depending upon the method and size of the storage container placed to receive the distilled liquid from the delivery tube  65 .