JP2008006380A - Method for freeze pulverization and vacuum drying of waste and system therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for freeze pulverization and vacuum drying of waste with excellent energy efficiency and system for the method. <P>SOLUTION: The method for freeze pulverization and vacuum drying of waste involves a freeze pulverization step of freezing water-containing waste and pulverizing the waste; a vacuum drying step of decreasing pressure of the waste frozen and pulverized in the freeze pulverization step to approximately vacuum state and sublimating the water contained in the waste in a frozen state; and turning the waste in a low-temperature and low-pressure state to a normal-temperature and normal-pressure state by introducing dry air in a normal-temperature and normal-pressure state to the waste from which the water is removed in the vacuum drying step. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for freeze-pulverizing and drying a waste having excellent energy efficiency and a system thereof.

  In recent years, technologies for gasifying and reusing waste have been developed. In such a technique, in order to gasify efficiently a waste having a high water content, it is necessary to dry the waste in advance so that the water content is about 20% or less. It is desirable to grind. In addition, as waste with a high moisture content, biomass, such as garbage, sewage sludge, and thinning, is mentioned, for example, and the moisture content is about 50% to about 90%.

  Therefore, conventionally, for example, when drying biomass, a technique of drying with hot hot air is widely used. Moreover, there is also a vacuum drying method in which the biomass is dried at a low temperature by lowering the boiling point of water by lowering the atmospheric pressure in the container containing the biomass (see, for example, Patent Document 1). Furthermore, there is a technique for dehydrating biomass (sewage sludge) by repeating freezing and thawing a plurality of times using the cold heat of LNG (Liquefied Natural Gas) (for example, see Patent Document 2).

On the other hand, when pulverizing biomass, a cutter mill or the like is usually used. For example, a technique of pulverizing biomass with a cutter mill or the like after freezing and hardening the biomass is well known. Furthermore, there is also a technique for freeze-pulverizing biomass (garbage) using the cold heat of LNG (see, for example, Patent Document 3).
JP 2002-59117 A Japanese Patent No. 2768117 JP-A-8-1035

  However, when a waste having a high water content such as biomass is dried with hot air, heating at a high temperature of 100 ° C. or higher is required, and much heat energy is required. Moreover, also when drying this waste material in vacuum, a heating of about 40-60 degreeC is needed, and energy efficiency is bad. In addition, when pulverizing waste using a cutter mill at room temperature, for example, when pulverizing waste to about 50 to 100 mm, much labor and time are required, and energy efficiency is similarly poor.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a waste freeze freeze-drying vacuum drying method and system excellent in energy efficiency.

  In order to solve the above-mentioned problems, a freeze-pulverization vacuum drying method for waste according to the present invention includes a freeze-pulverization step of freezing and pulverizing waste containing water, and the waste freeze-pulverized in the freeze-pulverization step. Place under a reduced pressure environment and sublimate and remove the frozen moisture contained in the waste, and dry waste at room temperature and normal pressure to the waste from which the moisture has been removed in the vacuum drying step. And introducing the waste in a low temperature and low pressure state to a normal temperature and normal pressure state.

  According to the configuration of the present invention, it is sufficient to supply heated air of about 20 ° C. to 50 ° C. as sublimation latent heat when sublimating moisture contained in the waste, and as a result, a low temperature heat source of 50 ° C. or less. Since it becomes possible to dry waste only by heating, the thermal energy required for heating can be greatly reduced. In addition, when the waste is dried at a low temperature in this way, unlike the case where the waste is dried at a high temperature, the physical properties of the waste are hardly changed. Further, when supplying the sublimation latent heat to the waste, since the waste is in a pulverized state, the heat supply becomes relatively easy and the speed of sublimation drying is improved. Furthermore, since the water contained in the waste is sublimated into a gas without melting from the ice state, the waste can be efficiently dried from the inside, and the energy efficiency is excellent.

Further, in the freeze pulverization vacuum drying method for waste according to the present invention, the freeze pulverization step includes introducing cooling air into the waste and freezing the waste, and the cooling air is used at normal temperature. What was obtained by heat-exchanging the dry air of a pressure state with LNG is preferable.
According to the configuration of the present invention, since the waste is directly frozen by the cooling air, the energy efficiency in the freeze pulverization process is improved, and furthermore, the cold heat of LNG can be effectively used in this freeze pulverization process. , Energy efficient.

Moreover, in the freeze pulverization vacuum drying method of the waste according to the present invention, methane gas generated by LNG vaporization when the dry air is heat-exchanged with the LNG is recovered, and the methane gas is used as a driving energy source of the generator. And using the electric energy obtained by driving the generator as an energy source for pulverizing the waste in the freeze pulverization step or an energy source for drying the waste under reduced pressure in the vacuum drying step It is preferable to reuse.
According to the configuration of the present invention, it is possible to effectively use the methane gas generated when heat is exchanged between LNG and normal temperature and pressure in the freeze pulverization step or the vacuum drying step. It is excellent in energy efficiency.

Moreover, in the freeze pulverization vacuum drying method of the waste according to the present invention, the vacuum drying step uses the vacuum pump to place the waste in the reduced pressure environment, sublimate the water and suck water vapor, It is preferable to include cooling and solidifying the water vapor being sucked and collecting, and when cooling and solidifying the water vapor, it is preferable to use cooling air obtained by heat exchange between LNG and dry air.
According to the configuration of the present invention, it is possible to reduce the volume by making the sucked water vapor into an ice state, and even if the suction amount from the vacuum pump is small, the waste can be easily made into a substantially vacuum state and dried. Therefore, it is excellent in energy efficiency. In addition, when using cooling air obtained by heat-exchange between LNG and dry air when cooling and solidifying water vapor, it is possible to effectively use the cold heat of LNG, which makes it even more energy efficient. It will be excellent.

Moreover, in the freeze pulverization vacuum drying method of the waste according to the present invention, the vacuum drying step measures the pressure state of the waste using a vacuum gauge, and the measurement value is a measurement value when sublimating the moisture. It is characterized in that the completion of the drying is detected when it is lowered.
According to the configuration of the present invention, it is possible to immediately determine whether or not the vacuum drying process has been completed. Therefore, energy efficiency is improved by omitting unnecessary vacuum drying.

The waste freeze-drying vacuum drying method according to the present invention is characterized in that the waste is biomass.
According to the configuration of the present invention, it is possible to gasify after sufficiently drying biomass having a high water content, and in this case, the gasification efficiency of the waste is improved, so that the energy efficiency is further improved. It will be a thing.

  In addition, the waste freeze pulverization vacuum drying system according to the present invention freezes and pulverizes waste containing moisture, and places the waste in a reduced pressure environment to sublimate the frozen moisture contained in the waste. Then, the waste is frozen and pulverized and vacuum dried to return the waste in a low temperature and low pressure state to a normal temperature and normal pressure state by introducing dry air in a normal temperature and normal pressure state into the waste, and the waste And a cooling air supply device for supplying cooling air for freezing to the freeze pulverization vacuum drying device.

Moreover, in the freeze pulverization vacuum drying system for waste according to the present invention, the cooling air supply device exchanges heat between LNG and dry air in a normal temperature and normal pressure state, and cooling air and methane gas obtained by heat exchange. And the cooling air is supplied to the freeze pulverization vacuum drying apparatus.
According to the configuration of the present invention, it is possible to effectively use the cold heat of LNG when freezing and pulverizing waste, so that the energy efficiency is excellent.

Further, the present invention is a waste freeze pulverization vacuum drying system comprising a freeze pulverization vacuum drying apparatus for freezing and pulverizing a waste containing moisture and drying the waste, and dry air at normal temperature and pressure. A heat exchanger for obtaining cooling air for freezing the waste by heat exchange with LNG and heating air for sublimating moisture of the freeze-pulverized waste are supplied to the freeze-pulverization vacuum drying apparatus. A heated air supply device, a dry air supply device that supplies dry air in a normal temperature and normal pressure state to the heat exchanger and the freeze pulverization vacuum drying device, and transports the waste material that has been freeze pulverized by the freeze pulverization vacuum drying device And a gasification furnace disposed on the downstream side of the belt conveyor for gasifying the waste, wherein the freeze pulverization vacuum drying apparatus includes a receiving hopper for storing the waste, A freezing tank for freezing the waste stored in the input hopper, a crushing tank for crushing the waste frozen in the freezing tank, and the waste frozen and crushed in the crushing tank under a substantially vacuum state A vacuum drying tank for drying in the vacuum drying chamber, and a heating tank for heating the waste material vacuum-dried in the vacuum drying tank. The tanks are connected to each other through a shutter.
In the present invention, the container for cooling and the container for heating are separated from each other, and the freeze pulverization and vacuum drying of the waste are continuously processed by the flow operation. Therefore, compared with the case where cooling and heating are repeated in the same container, energy efficiency is further improved.

Further, the present invention is a waste freeze pulverization vacuum drying system comprising a freeze pulverization vacuum drying apparatus for freezing and pulverizing a waste containing moisture and drying the waste, and dry air at normal temperature and pressure. A heat exchanger for obtaining cooling air for freezing the waste by heat exchange with LNG and heating air for sublimating the moisture of the freeze-pulverized waste are supplied to the freeze-pulverization vacuum drying apparatus. A heating air supply device, and a drying air supply device for supplying dry air in a normal temperature and normal pressure state to the heat exchanger and the freeze pulverization vacuum drying device, wherein the freeze pulverization vacuum drying device is a container for carrying biomass And a conveyor belt that conveys the container, and a receiving hopper that can be attached to the container in order from the upstream side to the downstream side above the belt conveyor, and attachable to the container A lid for freezing, a lid for the mountable ground into the container, characterized in that it and a lid for vacuum drying can be mounted to the container.
In the present invention, the container for cooling and the container for heating are made the same, and the freeze pulverization and vacuum drying of the waste are divided on the belt conveyor. Therefore, the waste is continuously processed by the flow operation, and the energy efficiency is further improved.

  ADVANTAGE OF THE INVENTION According to this invention, the freeze pulverization vacuum drying method and system of the waste excellent in energy efficiency can be provided.

  Hereinafter, each embodiment of the present invention will be described with reference to biomass as an example of waste.

=== Basic Configuration of the Present Invention ===
The biomass freeze-pulverization vacuum drying system in the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a basic configuration of a biomass freeze-pulverization vacuum drying system in the first embodiment of the present invention, and FIG. 2 is a diagram showing a system flow of the present invention.

  As shown in FIG. 1, the freeze pulverization vacuum drying system 100 for biomass includes a freeze pulverization vacuum drying device 10, a heat exchanger 11, a vacuum pump 12, a heated air supply device 13, a dry air supply device 14, It has. The heat exchanger 11, the vacuum pump 12, the heated air supply device 13, and the dry air supply device 14 are connected to the freeze pulverization vacuum drying device 10 via pipes 21, 22, 23, and 24, respectively. Valves 31, 32, 33, and 34 are provided in the pipes, respectively. A condenser 15 is provided in the middle of the pipe 22, and the condenser 15 is connected to the pipe 21 via a pipe 26. The dry air supply device 14 is connected to the heat exchanger 11 through a pipe 25.

  The freeze pulverization vacuum drying apparatus 10 includes a vacuum vessel 1 for storing biomass 4 and a heat radiation jacket 2 for releasing heat into the vacuum vessel 1, and a rotary blade 3 for stirring and pulverization is provided in the vacuum vessel 1. It has been. The freeze pulverization vacuum drying apparatus 10 is provided with a vacuum gauge 5 for measuring the pressure in the vacuum container 1.

The heat exchanger 11 heat-exchanges dry air in a normal temperature and normal pressure state with LNG (about −161 ° C.). The heat exchanger 11 cools the dried air (about −120 ° C. at about −120 ° C.). Extremely cold air) and methane gas (CH ₄ gas) in which LNG is vaporized are obtained. The cooling air is used for freeze pulverization and vacuum drying of the biomass 4 and is used in the condenser 15. In addition, about methane gas, it is preferable to utilize as a drive energy source of a generator so that it may mention later.

  The vacuum pump 12 is a pump for sucking the air in the vacuum vessel 1 and setting the pressure to a substantially vacuum state. The heated air supply device 13 is a device for supplying heated air (20 to 50 ° C.) to the heat radiating jacket 2. The dry air supply device 14 is a device for supplying dry air in a normal temperature and normal pressure state to the heat exchanger 11 and the vacuum vessel 1.

Next, a processing flow in the present embodiment will be described with reference to FIG.
As shown in FIG. 2, biomass 4 (for example, dewatered sludge, woody system, garbage, etc.) is stored in the vacuum vessel 1 (S200). Then, the valve 31 is opened and the valves 32, 33, and 34 are closed. The cooling air obtained by the heat exchanger 11 flows through the pipe 21 and is supplied into the vacuum vessel 1 through the valve 31 in the open state. The inside of the vacuum vessel 1 is in a refrigerated state when cooling air is supplied (S201). In addition, when supplying cooling air in the vacuum vessel 1, the rotary blade 3 is rotated and the biomass 4 is fully stirred. Biomass 4 is a kind of waste having a high moisture content, and is frozen when cooling air is supplied, and the water contained therein becomes ice. The frozen biomass 4 is pulverized by the rotation of the rotary blade 3 provided in the vacuum vessel 1 (S202).

  Next, the valve 31 is closed and the valve 32 is opened. Then, the vacuum chamber 1 is evacuated using the vacuum pump 12 (S203). Thereby, the cooling air in the vacuum vessel 1 flows through the pipe 22 through the valve 32 in the open state, and is exhausted through the vacuum pump 12. The pressure state in the vacuum vessel 1 is reduced to a state close to a vacuum state (for example, 10 Pa).

  Next, the valve 33 is opened while the valve 32 is open. The heated air (about 20 to 50 ° C.) supplied from the heated air supply device 13 flows through the pipe 23 and is supplied into the heating jacket 2 through the valve 33 (S204). The heated air is supplied as sublimation latent heat to the biomass 4 frozen and pulverized through the heating jacket 2. When sublimation latent heat is supplied in a substantially vacuum state, the moisture in the biomass 4 sublimates and changes from ice to water vapor (S205). This water vapor flows through the valve 22 through the valve 32 and is exhausted through the vacuum pump 12 by the above-described evacuation. Since the condenser 15 is provided in the middle of the pipe 22, the water vapor flowing through the pipe 22 is cooled and condensed by the condenser 15, and further cooled and solidified. The condenser 15 is supplied with cooling air, which is the cold heat of LNG, via the pipe 26, and the cold heat of LNG is effectively used.

  In addition, when the sublimation of the moisture contained in the biomass 4 is completed, the vacuum drying of the biomass 4 is finished, and the pressure in the vacuum vessel 1 starts to decrease. Therefore, the pressure state in the vacuum vessel 1 is measured using the vacuum gauge 5, and the completion of drying is detected when the measured value is lower than the measured value during sublimation.

  Next, when drying of the biomass 4 is completed, the valve 32 is closed and the valve 34 is opened. The valve 33 may be closed or open. The dry air in the normal temperature and normal pressure state supplied from the dry air supply device 14 is supplied into the vacuum vessel 1 through the pipe 24 and the open valve 34 (S206). By introducing dry air in a normal temperature and normal pressure state into the biomass 4 in the vacuum vessel 1, the low temperature and low pressure biomass 4 is returned to a normal temperature and normal pressure state. Thereby, grinding | pulverization and drying of the biomass 4 are completed. The biomass thus obtained has a low moisture content and is 20% or less, and is in a pulverized state, so that the energy efficiency for gasification is good.

=== Continuous processing system ===
The biomass freeze-pulverization vacuum drying system of the present invention will be described with reference to FIGS. 3 and 4. Each of the systems shown in the figures is one that continuously processes freeze pulverization and vacuum drying of biomass by a flow operation, and each corresponds to another embodiment described below. However, FIG. 4 shows only the main part of the present invention.

<Second embodiment>
First, a second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 3, the biomass freeze pulverization vacuum drying system 300 includes a freeze pulverization vacuum drying device 10, a heat exchanger 11, a vacuum pump 12, a heated air supply device 13, a dry air supply device 14, A belt conveyor 111 and a biomass gasification furnace 112 are provided.

  The freeze pulverization vacuum drying apparatus 10 includes a receiving hopper 101 for storing the biomass 4, a freezing tank 102 for freezing the biomass stored in the receiving hopper 101, a pulverizing tank 103 for pulverizing the biomass frozen in the freezing tank 102, A vacuum drying tank 104 for drying the biomass freeze-pulverized in the crushing tank 103 under a substantially vacuum state, each tank being arranged in order from above, and each of the upper and lower tanks via shutters 106 to 108, respectively. It is connected. A shutter 109 is provided below the vacuum drying tank 104. When the shutter 109 is opened, the contents stored in the vacuum drying tank 104 fall onto the belt conveyor 111 and are carried to the biomass gasification furnace 112. It is supposed to be.

  The freezing tank 102 is provided with a stirring blade 113 for stirring the biomass, while the crushing tank 103 is provided with a crushing blade 114 for crushing the frozen biomass. The vacuum drying tank 104 includes a vacuum container 115 that stores biomass and a heat radiation jacket 116 that releases heat to the vacuum container 115.

  The heat exchanger 11 is connected to the inside of the freezing tank 102 through a pipe 21. The vacuum pump 12 is connected to the inside of the vacuum container 115 of the vacuum drying tank 104 through a pipe 22. A condenser 15 is provided in the middle of the pipe 22, and the condenser 15 is connected to the pipe 21 via a pipe 26. The heated air supply device 13 is connected to the inside of the heat radiation jacket 116 of the vacuum drying tank 104 through a pipe 23. The dry air supply device 14 is connected to the inside of the vacuum container 115 of the vacuum drying tank 104 through a pipe 24, and is further connected to the heat exchanger 11 through a pipe 25. The heated air supply device 13 shown in the figure is connected to a pipe 24 via a pipe 27. Further, the piping 21, the piping 22, the piping 23, and the piping 24 are provided with a valve 31, a valve 32, a valve 33, and a valve 34, respectively, at predetermined positions.

  In the above configuration, the biomass 4 is first stored in the receiving hopper 101. When the shutter 106 is opened, the biomass stored in the receiving hopper 101 falls and is stored in the freezing tank 102. Next, the shutter 106 is closed and the valve 31 is opened. As a result, the cooling air (extremely cold air at about −120 ° C.) obtained by the heat exchanger 11 is introduced into the freezing tank 102. The biomass stored in the freezing tank 102 is frozen while being stirred by the stirring blade 113.

  Next, when the shutter 107 is opened, the biomass frozen in the freezing tank 102 falls and is stored in the crushing tank 103. When the shutter 107 is closed and the grinding blade 114 is driven, the frozen biomass stored in the grinding tank 103 is crushed.

  Next, when the shutter 108 is opened, the frozen biomass pulverized in the pulverization tank 103 falls and is stored in the vacuum container 115 of the vacuum drying tank 104. Next, the shutter 108 is closed, the valve 32 is opened, and the vacuum chamber 115 is evacuated using the vacuum pump 12. As a result, the cooling air in the vacuum container 115 flows through the pipe 22 through the open valve 32 and is exhausted through the vacuum pump 12. As a result, the pressure state in the vacuum vessel 115 is reduced to a state close to a vacuum state (for example, 10 Pa).

  Next, the valve 33 is opened while the valve 32 is kept open. The heated air (about 20 to 50 ° C.) supplied from the heated air supply device 13 flows through the pipe 23 and is supplied into the heating jacket 116 through the valve 33. Heat of the heated air is supplied as sublimation latent heat to the biomass in the vacuum vessel 115 via the heating jacket 116. When sublimation latent heat is supplied in a substantially vacuum state, the moisture of the biomass sublimates and changes from ice to water vapor. This water vapor flows through the valve 22 through the valve 32 and is exhausted through the vacuum pump 12 by the above-described evacuation. Since the condenser 15 is provided in the middle of the pipe 22, the water vapor flowing through the pipe 22 is cooled and condensed by the condenser 15, and further cooled and solidified. As in the case of FIG. 1, the condenser 15 is supplied with cooling air, which is the cold heat of the LNG, via the pipe 26, and the cold heat of the LNG is effectively used. Although not shown, the pressure state in the vacuum vessel 115 is measured using the vacuum gauge 5 similar to FIG. 1, and the completion of drying is detected when the measured value is lower than the measured value at the time of sublimation. May be.

  When the drying of the biomass is completed, the valve 32 and the valve 33 are closed and the valve 34 is opened. When the valve 34 is opened, dry air is supplied from the dry air supply device 14 to the biomass stored in the vacuum container 115 of the vacuum drying tank 104. By introducing dry air in a normal temperature and normal pressure state into the biomass in the vacuum vessel 115, the low temperature and low pressure biomass returns to the normal temperature and normal pressure state.

  Next, the shutter 109 is opened. The biomass that has returned to the normal temperature and normal pressure state falls on the belt conveyor 111. This biomass is conveyed to the biomass gasification furnace 112 by the belt conveyor 111. The conveyed biomass is put into the biomass gasification furnace 112 and gasified. Biomass to be input has a low moisture content and is 20% or less, and is in a pulverized state, so that energy efficiency for gasification is good. Further, in the case of the present embodiment, the containers for cooling and heating are separately provided, and the freeze pulverization and vacuum drying of the biomass are continuously processed by the flow operation. Therefore, compared with the case of FIG. 1 which repeats cooling and heating in the same container, energy efficiency improves further.

<Third embodiment>
Next, a third embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 4, the main part of the biomass freeze-pulverization vacuum drying system includes a belt conveyor 111, a biomass transport container 200, a receiving hopper 201, a freezing lid 202, and a grinding lid 203. And a lid 204 for vacuum drying, and further, a heating air supply means (not shown) is provided.

The container 200 is a container having an opening on the upper side. In addition, the receiving hopper 201, the freezing lid 202, the crushing lid 203, and the vacuum drying lid 204 are sequentially arranged from the upstream side along the belt conveyor 111, and all of them can move in the vertical direction. At the same time, it is connected to the upper side of the container 200 in a sealed state.
The receiving hopper 201 is for storing the biomass 4, and a shutter 106 is provided below the receiving hopper 201.

The freezing lid 202 is for freezing the biomass stored in the container 200. The refrigeration lid 202 is connected to the cooling air supply device 41 via the pipe 21, and the pipe 21 is provided with a valve 31. The cooling air supply device 41 is a device for supplying cooling air (extremely cold air at about −120 ° C.) into the container 200. The freezing lid 202 is provided with a stirring blade 113 driven by a motor.
The crushing lid 203 is for crushing the biomass stored in the cold vessel 200, and is provided with a crushing blade 114 driven by a motor.

  The lid 204 for vacuum drying is for vacuum drying the biomass stored in the cold container 200. The lid 204 for vacuum drying is connected to the vacuum pump 12 via a pipe 22, and a valve 32 is provided on the pipe 22. The lid 204 for vacuum drying is connected to the dry air supply device 14 via the pipe 23, and the pipe 23 is provided with a valve 33. The dry air supply device 14 is a device for supplying dry air in a normal temperature and normal pressure state to the biomass in the container 200.

  In the above configuration, the biomass 4 is first stored in the receiving hopper 201. Next, the shutter 106 of the receiving hopper 201 is opened, the biomass stored in the receiving hopper 201 is dropped, and stored in the container 200 disposed immediately below the biomass. Next, the belt conveyor is driven, and the container 200 containing the biomass is moved to just below the freezing lid 202. The freezing lid 202 is moved downward and connected to the container 200. Next, the valve 31 is opened, cooling air is introduced into the biomass in the container 200, and the biomass is frozen while stirring with the stirring blade 113. When the freezing of the biomass is completed, the freezing lid 202 is moved upward.

  Next, the belt conveyor is driven to move the container 200 containing the biomass to just below the crushing lid 203. The crushing lid 203 is moved downward and connected to the container 200. Then, the crushing blade 114 of the crushing lid 203 is driven to crush the frozen biomass. When the pulverization of the biomass is completed, the pulverization lid 203 is moved upward.

  Similarly, the belt conveyor is driven to move the container 200 containing the biomass to just below the vacuum drying lid 204. The lid 204 for vacuum drying is moved downward and connected to the container 200. Next, the valve 32 is opened with the valve 33 closed, and the vacuum in the container 200 is evacuated using the vacuum pump 12. Thereby, the pressure state in the container 200 is reduced to a substantially vacuum state (for example, 10 Pa). Next, sublimation latent hot air (heated air of about 20 to 50 ° C.) is supplied into the container 200 using a heated air supply device 13 (not shown). When the sublimation latent heat is supplied in a substantially vacuum state, the moisture of the biomass starts from sublimation and changes from ice to water vapor. This water vapor flows through the valve 22 through the valve 32 and is exhausted through the vacuum pump 12 by the above-described evacuation. Although not shown in FIG. 4, as described above, it is preferable to provide the condenser 15 in the middle of the pipe 22 in order to perform evacuation efficiently.

  Next, the valve 32 is closed and the valve 33 is opened, and the dry air is supplied into the container 200 using the dry air supply device 14. Thereby, the biomass in the container 200 changes from the low temperature and low pressure state to the normal temperature and normal pressure state.

  As described above, according to the biomass freeze-pulverization vacuum drying system, biomass in a dry state (moisture content is 20% or less) and in a pulverized state can be efficiently obtained. In the case of the present embodiment, the containers for cooling and heating are made the same, and the freezing and pulverization of biomass and vacuum drying are divided on the belt conveyor. Therefore, the biomass is continuously processed by the flow operation, and the energy efficiency is further improved.

=== Various application examples ===
Next, application examples of the freeze pulverization vacuum drying apparatus according to the present invention will be described with reference to FIGS. FIG. 5 is a diagram showing an example of application to a natural gas power plant, FIG. 6 is a diagram showing an example of application to a dual fuel diesel generator, and FIG. 7 is a diagram showing an example of application to a waste treatment plant.

<Application example 1: Application example to a natural gas power plant>
First, an application example of the freeze pulverization vacuum drying apparatus 10 to a natural gas power plant will be described.
As shown in FIG. 5, the freeze pulverization vacuum drying apparatus 10 is connected to a heat exchanger 11 and a biomass gasification furnace 51. The heat exchanger 11 is connected to the dry air supply device 14 and the LNG tank 56. The heat exchanger 11 and the biomass gasification furnace 51 are connected to a gas mixer 52, and the gas mixer 52 is further connected to a gas turbine 53. The gas turbine 53 is connected to a steam turbine 54, and the steam turbine 54 is further connected to a generator 55. The gas turbine 53 and the steam turbine 54 are connected to the biomass gasification furnace 51. The generator 55 is connected to the freeze pulverization vacuum drying apparatus 10.

As described above, when the freeze pulverization vacuum drying apparatus 10 is applied to a natural gas power plant, the cold air is generated by using the LNG cold heat by the heat exchanger 11 and then frozen. The pulverization vacuum drying apparatus 10 can be effectively used. Further, the biomass can be efficiently gasified in the biomass gasification furnace 51 by pulverizing and drying the biomass by the freeze pulverization vacuum drying apparatus 10. Moreover, biogas _{(e.g., CO, CH 4, H 2} ) by the gas mixer 52 and the natural gas (e.g., CH ₄₎ With the mixed fuel can be effectively utilized these gases. Further, the exhaust heat generated in the gas turbine 53 and the steam turbine 54 can be effectively used as a heat source for the biomass gasification furnace 51. Furthermore, the electric power generated by the generator 55 can be effectively used as an electric power source for the freeze pulverization vacuum drying apparatus 10.

<Application Example 2: Application to Dual Fuel Diesel Generator>
Next, an application example of the freeze pulverization vacuum drying apparatus 10 to a dual fuel diesel generator will be described.

  As shown in FIG. 6, the freeze pulverization vacuum drying apparatus 10 is connected to a heat exchanger 11 and a biomass gasification furnace 51. The heat exchanger 11 is connected to the dry air supply device 14 and the LNG tank 56. The heat exchanger 11 and the biomass gasification furnace 51 are connected to a gas mixer 52, and the gas mixer 52 is further connected to a diesel engine 58 via an intake port 57. The diesel engine 58 is connected to the biomass gasification furnace 51, the generator 55, and the heavy oil tank 59. The generator 55 is connected to the freeze pulverization vacuum drying apparatus 10.

  As described above, when the freeze pulverization vacuum drying apparatus 10 is applied to a dual fuel diesel generator, the same effects as in the case of FIG. 5 are obtained, and effective use of LNG cold heat and improvement of gasification efficiency are achieved. be able to. Further, the mixed gas obtained in the gas mixer 52, that is, the mixed gas of the biogas generated in the biomass gas furnace 51 and the natural gas generated in the heat exchanger 11 is further mixed with the atmosphere, and then these gases are mixed. Can be effectively used in the diesel engine 58 together with the diesel oil supplied from the heavy oil tank 59. Further, the exhaust heat generated in the diesel engine 58 can be effectively used as a heat source for the biomass gas furnace 51. Further, the electric power generated by the generator 55 can be effectively used as the electric power source of the freeze pulverization vacuum drying apparatus 10.

<Application Example 3: Application to Garbage Treatment Plant>
Next, an application example of the freeze pulverization vacuum drying apparatus 10 to a garbage disposal site will be described.
As shown in FIG. 7, the freeze pulverization vacuum drying apparatus 10 is connected to a heat exchanger 11 and a biomass gasification furnace 51. The biomass gasification furnace 51 includes, for example, a drying system such as dry combustible waste and plastics. Garbage is supplied. The heat exchanger 11 is connected to the dry air supply device 14 and the LNG tank 56. The heat exchanger 11 and the biomass gasification furnace 51 are connected to a gas mixer 52. The gas mixer 52 is connected to a gas engine 61, and the gas engine 61 is further connected to a generator 55. The gas engine 61 is connected to the biomass gasification furnace 51. The generator 55 is connected to the freeze pulverization vacuum drying apparatus 10.

  As described above, when the freeze pulverization vacuum drying apparatus 10 is applied to a waste treatment plant, the same effects as in the case of FIG. 5 and FIG. 6 are obtained, and effective use of LNG cold heat and improvement of gasification efficiency are achieved. Can do. Further, in the biomass gasification furnace 51, dry waste can be effectively used. Further, the mixed gas obtained by the gas mixer 52, that is, the mixed gas of the biogas generated in the biomass gas furnace 51 and the natural gas generated in the heat exchanger 11 can be effectively used in the gas engine 61. Furthermore, the exhaust heat generated in the gas engine 61 can be effectively used as a heat source for the biomass gas furnace 51. Further, the electric power generated by the generator 55 can be effectively used as the electric power source of the freeze pulverization vacuum drying apparatus 10.

It is a figure which shows the basic composition of the freeze pulverization vacuum drying system of biomass in 1st embodiment of this invention. It is a figure which shows the processing flow in 1st embodiment of this invention. It is a figure which shows the freeze pulverization vacuum drying system of biomass in 2nd embodiment of this invention. It is a figure which shows the principal part of the freeze pulverization vacuum drying system of biomass in 3rd embodiment of this invention. It is a figure which shows the application example 1 at the time of applying the freeze-pulverization vacuum drying apparatus which concerns on this invention to a natural gas power plant. It is a figure which shows the application example 2 at the time of applying the freeze-pulverization vacuum drying apparatus which concerns on this invention to a dual fuel diesel generator. It is a figure which shows the example 3 of application at the time of applying the freeze pulverization vacuum drying apparatus which concerns on this invention to a refuse disposal site.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum container 2 Radiating jacket 3 Rotary blade for agitation and grinding 4 Biomass 5 Vacuum gauge 10 Freeze crushing vacuum dryer 100 Biomass freeze crushing vacuum drying system

Claims (12)

A freezing and pulverizing step of freezing and pulverizing water-containing waste,
A vacuum drying step of placing the waste freeze-pulverized in the freeze-pulverization step in a reduced-pressure environment and sublimating and removing the frozen water contained in the waste;
Introducing the dry air in a normal temperature and normal pressure state into the waste from which the moisture has been removed in the vacuum drying step, and returning the waste in a low temperature and low pressure state to a normal temperature and normal pressure state;
A method for freeze-pulverizing and vacuum-drying wastes, comprising: A method of freeze-pulverizing and vacuum-drying waste according to claim 1,
The freeze pulverization vacuum drying method of waste, wherein the freeze pulverization step includes introducing cooling air into the waste and freezing the waste. A method of freeze-pulverizing and vacuum-drying waste according to claim 2,
The method of freeze drying and pulverizing vacuum waste, wherein the cooling air is obtained by heat exchange of dry air at normal temperature and pressure with LNG. It is a freeze pulverization vacuum drying method of the waste according to claim 3,
Electric energy obtained by recovering methane gas generated by vaporization of LNG when the dry air is heat-exchanged with the LNG, using the methane gas as a drive energy source of the generator, and driving the generator And recycling the waste as an energy source for pulverizing the waste in the freeze pulverization step or an energy source for drying the waste under reduced pressure in the vacuum drying step . A method for freeze-grinding and vacuum-drying waste according to any one of claims 1 to 4,
The vacuum drying step includes placing the waste in the reduced-pressure environment using a vacuum pump, sublimating the water to suck water vapor, and cooling and solidifying the water vapor being sucked to recover. A method for freeze-pulverizing and drying vacuum waste. A method of freeze-pulverizing and vacuum-drying waste according to claim 5,
A method for freeze-pulverizing and drying vacuum waste, characterized in that when the water vapor is cooled and solidified, cooling air obtained by heat exchange of dry air at normal temperature and normal pressure with LNG is used. It is a freeze pulverization vacuum drying method of the waste according to claim 1,
In the vacuum drying step, the pressure state of the waste is measured using a vacuum gauge, and the completion of the drying is detected when the measured value is lower than the measured value when the moisture is sublimated. A method of freeze-grinding and vacuum drying waste. It is a freeze pulverization vacuum drying method of the waste according to claim 1,
The waste is freeze-pulverized vacuum drying method, wherein the waste is biomass. Freeze and pulverize the waste containing water, place the waste in a reduced pressure environment to sublimate and remove the frozen water contained in the waste, and then dry the waste at room temperature and normal pressure Freezing and pulverizing vacuum drying device for the waste to introduce air and return the waste in a low temperature and low pressure state to a normal temperature and normal pressure state;
A cooling air supply device for supplying cooling air for freezing the waste to the freeze pulverization vacuum drying device;
A freezing and pulverizing vacuum drying system for waste. A waste freeze pulverization vacuum drying system according to claim 9,
The cooling air supply device heat-exchanges dry air in a normal temperature and normal pressure state with LNG, separates the cooling air and methane gas obtained by heat exchange, and supplies the cooling air to the freeze-pulverization vacuum drying device A waste-freezing and pulverizing vacuum drying system. A waste freeze pulverization vacuum drying system according to claim 9 or 10,
Freezing and crushing vacuum drying apparatus that freezes and crushes waste containing moisture and dries the waste, and cooling air for freezing the waste by heat-exchanging dry air at normal temperature and normal pressure with LNG A heat exchanger to obtain, a heated air supply device for supplying heating air for sublimating the moisture of the freeze-pulverized waste to the freeze-pulverization vacuum drying device, and dry air in a normal temperature and normal pressure state to the heat exchanger And a dry air supply device for supplying to the freeze pulverization vacuum drying device, a belt conveyor for transporting the waste freeze pulverized by the freeze pulverization vacuum drying device, and the waste disposed on the downstream side of the belt conveyor. A gasification furnace for gasification,
The freeze pulverization vacuum drying apparatus is:
A receiving hopper for storing the waste, a freezing tank for freezing the waste stored in the receiving hopper, a crushing tank for crushing the waste frozen in the freezing tank, and the crushing tank; A vacuum drying tank for drying the frozen and pulverized waste under a substantially vacuum state, and a temperature raising tank for raising the temperature of the waste vacuum dried in the vacuum drying tank,
These waste tanks are arranged in order from above, and the upper and lower tanks are connected to each other via a shutter, and the waste freeze-pulverization vacuum drying system. A waste freeze pulverization vacuum drying system according to claim 9 or 10,
Freezing and pulverizing vacuum drying apparatus for freezing and pulverizing waste containing moisture and drying the waste, and cooling air for freezing the waste by heat exchange of dry air at normal temperature and normal pressure with LNG A heat exchanger to obtain, a heated air supply device for supplying heating air for sublimating the moisture of the freeze-pulverized waste to the freeze-pulverization vacuum drying device, and dry air in a normal temperature and normal pressure state to the heat exchanger And a dry air supply device for supplying to the freeze pulverization vacuum drying device,
The freeze pulverization vacuum drying apparatus is:
A container for carrying biomass and a belt conveyor for carrying the container, and a receiving hopper that can be attached to the container in order from the upstream side to the downstream side above the belt conveyor, and attached to the container A waste freeze freeze-drying vacuum drying system comprising: a freezing lid, a crushing lid attachable to the container, and a vacuum drying lid attachable to the container .

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