JP3961550B1 - Waste treatment apparatus for heating waste and sterilizing by dry heat, vehicle equipped with the same, and waste treatment method - Google Patents

Abstract

The present invention provides a waste treatment apparatus capable of dry heat sterilization of waste reliably and efficiently.
A waste treatment apparatus includes a drying tank, a sterilization tank, and a control unit. The control means determines that the waste 90 in the drying tank 30 has been dried based on the physical quantity change related to the waste 90 in the drying tank 30. The control means transfers the waste 90 in the drying tank 30 to the sterilization tank 40 after determining that the waste 90 in the drying tank 30 has dried.
[Selection] Figure 2

Description

  The present invention relates to a waste treatment apparatus for heating waste and sterilizing by dry heat, a vehicle equipped with the waste treatment apparatus, and a waste treatment method.

  Conventionally, waste that requires sterilization, such as infectious waste such as medical waste, has been incinerated. However, when waste is incinerated, harmful gases such as dioxins may be generated depending on the type of waste. For this reason, in recent years, various waste disposal methods for sterilizing waste without incineration have been proposed. Specifically, a dry heat sterilization method and a high-pressure steam sterilization method described in Patent Document 1 and the like have been proposed.

  Here, the dry heat sterilization method is a method in which waste is heated in a high temperature atmosphere (typically in a dry hot air atmosphere. It may be in a dry heat incombustible gas atmosphere). A method of killing microorganisms present in On the other hand, the high-pressure steam sterilization method is a method of killing microorganisms present in waste by exposing the waste to high-pressure and high-temperature steam. In the dry heat sterilization method, steam may be contained in the high-temperature atmosphere when sterilizing, but the dry heat sterilization method is different from the high-pressure steam sterilization method in that it does not actively use steam for sterilization of microorganisms. Different.

Among the above sterilization methods, the high-pressure steam sterilization method is preferable from the viewpoint of killing efficiency because microorganisms can be more effectively killed by using high-temperature steam. However, in the high-pressure steam sterilization method, it is necessary to form a high-pressure and high-temperature steam gas atmosphere, so that a pressure-resistant sealed sterilization tank is required. On the other hand, the dry heat sterilization method is widely practiced because it does not require such a pressure-resistant sealed sterilization tank and can be easily carried out with relatively simple equipment.
Japanese Patent No. 3502339

  By the way, when performing the dry heat sterilization method, if the waste to be sterilized contains moisture, part or all of the amount of heat to be applied to the waste in the sterilization process becomes latent heat of evaporation. . For this reason, the temperature of the waste in a sterilization tank becomes unstable. In addition, the temperature necessary for sterilizing waste (hereinafter, sometimes referred to as “sterilization temperature”) is higher than 100 ° C., and the amount of heat applied until the waste is dried. Most of this becomes latent heat of vaporization, and the temperature of the waste does not rise to a sterilization temperature exceeding 100 ° C. Therefore, the efficiency of sterilization in the sterilization tank is reduced. Therefore, as described in Patent Document 1, it is preferable to dry the waste prior to the sterilization step. Specifically, in Patent Document 1, prior to performing the sterilization process, the waste is directly brought into contact with a high-temperature heating medium at a predetermined temperature (180 to 250 ° C.) for a predetermined time (5 to 10 minutes). It is described to be dried.

  However, the water content of the waste varies from case to case. For example, if the waste contains a large amount of water, as described in Patent Document 1, it is dried for a predetermined time at a predetermined temperature, and in a uniform process regardless of the type and amount of waste, There are cases where the waste cannot be dried sufficiently. In that case, a sterilization process is performed on the waste in which moisture remains. For this reason, there exists a possibility that waste cannot be sterilized reliably and effectively. On the other hand, when the water content of the waste is relatively small, a drying process that takes an unnecessarily long time is performed.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a waste treatment apparatus and a waste treatment method capable of sterilizing waste reliably and efficiently. .

  The waste treatment apparatus according to the present invention is an apparatus for sterilizing waste that requires sterilization treatment such as infectious waste such as medical waste.

The waste disposal apparatus according to the present invention includes a drying tank, a sterilization tank isolated from the drying tank, and a control means. A drying tank heats and dries waste. The sterilization tank is used for heating and sterilizing the waste material dried in the drying tank. The control means determines that the waste in the drying tank has been dried based on a change in physical quantity related to the waste in the drying tank. After determining that the waste in the drying tank has been dried, the control means regulates that the waste in the drying tank is transferred to the sterilization tank, and the waste in which moisture remains is transferred to the sterilization tank. To do .

  According to the waste treatment apparatus, waste that has been dried in advance is put into the sterilization tank. Therefore, since the evaporation of water from the waste does not substantially occur in the sterilization tank, the temperature of the waste in the sterilization tank does not stay at around 100 ° C., and the sterilization temperature (to sterilize the waste quickly). To the required temperature). That is, there is little time loss until the temperature of the waste rises to the sterilization temperature, and the time required for the waste to rise to the sterilization temperature is almost constant. Therefore, it is possible to ensure a stable and long time for keeping the waste at the sterilization temperature. As a result, reliable and efficient sterilization can be performed.

  Moreover, it is judged based on the physical quantity change regarding the waste in a drying tank that the waste in a drying tank was dried. Here, “change in physical quantity related to waste in the drying tank” means temperature change of waste in the drying tank, weight of waste in the drying tank (total weight of the drying tank including the weight of waste). Or changes in humidity in the drying tank. Specifically, for example, when the temperature of the waste in the drying tank further exceeds 100 ° C., when the weight change of the waste is substantially eliminated, the humidity change in the drying tank is substantially eliminated. Sometimes it is judged that the waste in the drying tank is dry. For this reason, it can be reliably detected without delay that the waste in the drying tank is dried. Therefore, it is possible to reliably regulate the transfer of the waste in which moisture remains to the sterilization tank, and it is possible to minimize the time required for drying the waste.

  In addition, since the drying tank is independent of the sterilization tank, when the waste is dried and sterilized multiple times, both the drying tank and the sterilization tank are driven at the same time, Next, it becomes possible to simultaneously perform the drying process of the waste to be sterilized. Therefore, it becomes possible to sterilize waste efficiently in a shorter processing time.

  In this specification, “sterilization” is not limited to the complete removal of bacteria contained in an object to be sterilized (in this case, waste), but to the extent required by laws and regulations. It means to reduce the amount of bacteria contained in the sterilized object up to the amount. More specifically, “sterilization” refers to reducing the survival amount of microorganisms in an object to be sterilized to below the required sterility assurance level (SAL).

  It is preferable that the temperature of the waste in the drying tank is detected by the temperature detection means of the drying tank installed in the drying tank. The temperature detection means of the drying tank is preferably arranged so as to be in direct contact with the waste in the drying tank. The drying tank temperature detection means detects the temperature of the inner wall of the drying tank or the atmospheric temperature of the drying tank, and monitors the temperature of the waste in the drying tank based on the inner wall temperature or the atmospheric temperature. May be.

  The drying tank preferably includes a crushing means for crushing the waste, a retention part for retaining the crushed waste, and a heating means for the drying tank for heating the retention part. According to this configuration, the waste is finely crushed prior to the drying of the waste. For this reason, the waste can be dried in a short time without unevenness. Accordingly, it is possible to sterilize waste quickly.

  The drying tank further includes a drying tank agitation means for agitating the accumulated waste when the waste accumulated in the retention part is heated and dried by the drying tank heating means. Is preferred. According to this configuration, the waste can be dried while stirring. Therefore, it is possible to suppress temperature unevenness occurring in the staying waste, and it is possible to dry the waste uniformly and efficiently.

  The capacity of the sterilization tank is preferably set larger than the capacity of the drying tank. For example, the capacity of the sterilization tank is particularly preferably at least twice that of the drying tank. According to this configuration, waste that has been dried several times in the drying tank is temporarily stored in the sterilization tank. For example, when a certain amount of waste is stored in the sterilization tank or at a predetermined time, The stored waste can be sterilized in a batch. Therefore, a more efficient sterilization process can be performed and the energy cost required for the sterilization process can be reduced.

  The sterilization temperature is usually a relatively high temperature of, for example, 150 ° C. or higher. For this reason, if the inside of a sterilization tank is a normal air atmosphere, there exists a possibility that a waste may ignite in a sterilization process. When the waste is ignited and burned, there is a possibility that toxic gas such as dioxin is generated. Therefore, in order to suppress the ignition of waste, a gas supply means for supplying incombustible gas is provided in the sterilization tank, and when sterilizing waste, the gas supply means is driven to make the sterilization tank incombustible. A gas atmosphere is preferred. By doing so, it is possible to suppress the ignition of waste in the sterilization process.

  Here, the nonflammable gas refers to a gas that suppresses ignition of waste. Specific examples include inert gas such as nitrogen gas and argon gas, superheated steam, and the like. In addition, the non-combustible gas atmosphere refers to an atmosphere in which an incombustible gas is introduced and an oxygen concentration is suppressed as compared with the air (that is, an atmosphere in which waste is less likely to ignite than an air atmosphere).

  In addition, when the waste containing water | moisture content is thrown into the sterilization tank, there exists a possibility that the latent heat of evaporation will arise and the temperature of waste may become unstable. However, when superheated steam in a vaporized state is introduced into the sterilization tank, latent heat of vaporization does not occur, so the temperature of the waste in the sterilization tank does not become unstable. It may be preferable to introduce superheated steam as an incombustible gas as long as no condensation occurs in the sterilization tank.

  Further, since the sterilization temperature is a relatively high temperature as described above, the waste may be denatured or dissolved depending on the composition of the waste. For this reason, it is preferable to detect the temperature of the waste in the sterilization tank without using temperature detection means that directly contacts the waste in the sterilization tank. This is because in the temperature detection means that directly contacts the waste in the sterilization tank, the denatured or dissolved waste adheres, making it difficult to detect the temperature accurately. Therefore, for example, it is preferable to provide temperature detecting means for measuring the ambient temperature in the sterilization tank, thereby indirectly controlling the temperature of the waste in the sterilization tank. Note that a radiation thermometer or the like that directly measures the temperature of the waste may be used in place of the temperature detection means for measuring the atmospheric temperature in the sterilization tank or together with the temperature detection means.

  The heating means for the drying tank and the heating means for the sterilization tank may be an electric heater, a steam pipe or a burner for circulating high-temperature steam, respectively.

  By the way, in a sterilization tank, when a waste is heated in a stationary state without stirring, temperature unevenness occurs in the waste. In that case, the portion of the waste that has reached the sterilization temperature is efficiently sterilized, but the portion that does not reach the sterilization temperature at a relatively low temperature does not readily sterilize, and in some cases, waste that is not sufficiently sterilized There is a risk of remaining. Therefore, when the waste in the sterilization tank is provided with stirring means for stirring the waste in the sterilization tank and the waste in the sterilization tank is heated and sterilized, the waste is stirred by the stirring means in the sterilization tank. Is preferred. By doing so, the waste can be heated uniformly to the sterilization temperature. As a result, reliable and efficient sterilization is possible.

  The vehicle according to the present invention is equipped with the waste disposal apparatus according to the present invention. According to this, the sterilization treatment of the waste can be reliably and efficiently performed as described above at an arbitrary place. For this reason, even in a medical facility or the like that is not equipped with a waste treatment apparatus, the use of the vehicle according to the present invention enables reliable and efficient sterilization of waste on the site of the medical facility or the like.

The waste processing method according to the present invention includes a drying tank for heating and drying waste, and a sterilization tank isolated from the drying tank for dry heat sterilization by heating the waste dried in the drying tank. The present invention relates to a method for treating waste using a waste treatment apparatus comprising: The waste processing method according to the present invention includes an input process, a drying process, a determination process, and a sterilization process. The charging process is a process of charging waste into the drying tank. A drying process is a process of heating and drying the waste thrown into the drying tank. The judging step judges that the drying of the waste in the drying tank has been completed based on the physical quantity change regarding the waste in the drying tank in the drying process, and the waste in which moisture remains is transferred to the sterilization tank. It is a process of regulating what is done. Specifically, when the temperature of the waste in the drying tank further rises from 100 ° C., when the weight change of the waste in the drying tank is substantially eliminated, or the humidity change of the atmosphere in the drying tank is substantially This is a step of judging that the waste in the drying tank is dry when it disappears. The sterilization step is a step of sterilization by dry heat in a sterilization tank by heating the waste determined to be dried in the determination step.

  According to the waste treatment method, waste that has been dried in advance is transferred to the sterilization tank. For this reason, in the sterilization process, the temperature of the waste in the sterilization tank quickly rises to the sterilization temperature without staying around 100 ° C. That is, there is little time loss until the temperature reaches the sterilization temperature, and the time required for the temperature to rise to the sterilization temperature is almost constant. Therefore, it is possible to ensure a stable and long time for keeping the waste at the sterilization temperature. As a result, reliable and efficient sterilization can be performed.

  Moreover, since it is judged based on the physical quantity change regarding the waste in a drying tank that the drying of the waste in a drying tank is complete | finished, a waste is dried reliably in a drying process. Further, the time required for the drying process is kept to a minimum without performing the drying process unnecessarily for a long time.

  Further, from the viewpoint of drying the waste reliably and efficiently, it is preferable to perform a crushing step of crushing the waste prior to the drying step. By doing so, the size of each waste can be made relatively small, and the waste can be efficiently dried.

  Moreover, it is preferable to perform a drying process, stirring a waste material. By doing so, the temperature nonuniformity which arises in a waste material can be suppressed.

  The sterilization process may be performed every time the charging process and the drying process are performed, but after performing the charging process and the drying process a plurality of times, the wastes dried by the multiple drying processes are collectively sterilized. It is preferable to carry out. By doing so, the frequency | count of performing a sterilization process can be reduced and energy cost can be reduced. Moreover, it becomes possible to sterilize a large amount of waste efficiently.

  In addition, it is preferable to perform a sterilization process by making the inside of a sterilization tank into a nonflammable gas atmosphere. By doing so, ignition of waste in the sterilization process can be suppressed.

  Moreover, it is preferable to perform a sterilization process, stirring the waste in a sterilization tank. By doing so, waste can be heated evenly and sterilization can be performed reliably and efficiently.

  As described above, according to the present invention, waste can be sterilized reliably and efficiently.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a side view showing a configuration of a waste disposal vehicle 10 according to the present embodiment.

  FIG. 2 is a schematic diagram showing the configuration of the waste treatment apparatus 20.

  First, the configuration of the waste disposal vehicle 10 according to the present embodiment will be described with reference to FIGS. 1 and 2.

  The waste treatment vehicle 10 includes a vehicle main body 11 and a waste treatment device 20. The vehicle body 11 is an automobile (truck) provided with a loading platform 12. The waste treatment apparatus 20 is installed on the loading platform 12.

  As shown in FIG. 2, the waste treatment apparatus 20 includes a drying tank 30 and a sterilization tank 40. The waste treatment apparatus 20 is an apparatus for performing a dry heat sterilization treatment by further heating the waste dried by heating in the drying tank 30 in the sterilization tank 40.

  The drying tank 30 is for drying the waste 90. Specifically, the drying tank 30 is provided with an input port 31 for waste 90 that opens into the drying tank 30 slightly above the center of the drying tank 30. Usually, the insertion port 31 is separated from the inside of the drying tank 30 by an openable / closable door 31a. When throwing in the waste 90, the door 31 a is opened, and the waste 90 is put into the drying tank 30 from the inlet 31.

  The inside of the drying tank 30 is divided into two parts. Specifically, crushing means 32a is arranged, crushing part 32 that crushes input waste 90 finely, and positioned below crushing part 32 to retain crushed waste 90 and dry it It is divided into the retention part 33 to be made.

  The crushing means 32a is not particularly limited as long as it can crush the waste 90. The crushing means 32a may be a biaxial shearing type, for example. Moreover, as shown in FIG. 2, the crushing means 32a may be constituted by a disc-shaped lid member 32b and a crushing member 32c having a plurality of claws formed on the surface for crushing the waste 90. The lid member 32b can be displaced up and down, but cannot rotate, and presses the waste 90 put between the lid member 32b and the crushing member 32c toward the crushing member 32c by its own weight. On the other hand, the crushing member 32c is fixed to the tip of a shaft 38 connected to a driving means 37 constituted by a motor or the like so as not to be displaced up and down, and is rotated by the driving means 37. The crushing member 32c is formed with a large number of holes so that the waste 90 finely crushed by the claws falls from the crushing member 32c into the staying portion 33 below.

  A heating unit 34 is disposed in the staying part 33. The waste material 90 retained in the retention part 33 is heated and dried by the heating means 34. The heating means 34 is not particularly limited. As the heating means 34, a steam pipe for circulating high-temperature steam may be circulated along the outer periphery of the staying portion 33 of the drying tank 30, and a burner may be disposed below the staying portion 33. Further, an electric heater may be arranged on the outer periphery of the staying part 33 as the heating means 34. By using an electric heater as the heating means 34, the waste 90 can be efficiently heated.

  The staying part 33 is provided with a plate-like stirring means 36 for stirring the waste 90 staying in the staying part 33. The stirring means 36 is connected to a shaft 38 and is rotationally driven by a driving means 37 together with the shaft 38.

  Furthermore, the staying part 33 is provided with temperature detecting means 35 for detecting the temperature of the staying waste 90. The temperature detecting means 35 is disposed so as to contact the staying waste 90, and can directly detect the temperature of the staying waste 90. As described above, in the present embodiment, the temperature detection unit 35 that is in contact with the staying waste 90 and can directly measure the temperature of the waste 90 is used. A temperature detecting means for detecting the temperature of the waste 90 may be provided so that the temperature of the waste 90 is controlled by the ambient temperature or the tank inner wall temperature.

  The drying tank 30 communicates with the sterilization tank 40 through a pipe 50 connected to the discharge port 39 of the staying part 33. Inside the pipe 50, a transfer conveyor 51 is provided as a transfer means for transferring the waste 90. The drying tank 30 and the pipe 50 are partitioned by an openable / closable door 39 a installed at the discharge port 39 of the drying tank 30.

  A heating unit 52 for heating the waste 90 passing through the pipe 50 is provided outside the pipe 50. By this heating means 52, the waste 90 transferred through the pipe 50 is heated or kept warm.

  In addition, the conveyance conveyor 51, the heating means 34 and 42, the stirring means 41, and the like are controlled by a control means (not shown). The control means may be provided for each constituent member, but all the constituent members may be collectively controlled by one control means.

  The sterilization tank 40 is a tank for sterilizing the waste 90 transferred from the drying tank 30. The sterilization tank 40 has a larger capacity (for example, twice or more capacity) than the drying tank 30. The sterilization tank 40 is provided with a stirring means 41 having a plurality of stirring paddles 41a extending radially on an axis extending in the longitudinal direction.

  Further, the sterilization tank 40 is provided with heating means 42 arranged along the outer periphery of the sterilization tank 40. The waste 90 in the sterilization tank 40 is heated by the heating means 42. In this embodiment, the temperature of the waste 90 in the sterilization tank 40 is controlled based on the temperature that is provided in the sterilization tank 40 and detected by the temperature detection means 43 that measures the ambient temperature in the sterilization tank 40. Has been.

  Below the sterilization tank 40, a discharge port 44 for taking out the sterilized waste 90 from the sterilization tank 40 and an openable / closable door 44 a are provided.

  The sterilization tank 40 is connected to a gas supply means (for example, a gas cylinder) 80 for supplying nonflammable gas via a pipe 81. The gas supply means 80 is controlled by a control means (not shown). When the waste 90 is heated and sterilized in the sterilization tank 40, non-combustible gas is supplied from the gas supply means 80 into the sterilization tank 40, and sterilization is performed. The inside of the tank 40 becomes an incombustible gas atmosphere. The incombustible gas is a gas for suppressing the ignition of the waste 90. Specifically, examples of the nonflammable gas include inert gases such as nitrogen gas and argon gas, superheated steam, and a mixed gas of these gases. Further, the incombustible gas atmosphere refers to an atmosphere in which an incombustible gas is introduced and an oxygen concentration is suppressed as compared with the atmosphere.

  Each of the drying tank 30 and the sterilization tank 40 is connected to a dust collection deodorization device 70 via a pipe 61. The exhaust gas discharged from the drying tank 30 and the sterilization tank 40 (including superheated steam generated from the drying tank 30) is purified by the dust collection deodorization device 70 and is discharged to the atmosphere. A hot air generator 60a is provided in the middle of the pipe 61, and the hot air is circulated through the pipe 61 by the hot air generator 60a so that the inside of the pipe 61 is sterilized. Moreover, the hot air generator 60b is installed also with respect to the piping 50 which connects the drying tank 30 and the sterilization tank 40, and the inside of the piping 50 can be heated and sterilized by operating the hot air generator 60b suitably. It has a configuration.

  Next, the operation of the waste disposal apparatus 20 will be described.

  FIG. 3 is a flowchart of the waste processing performed in the waste processing apparatus 20.

  First, the drying tank 30 is preheated to a predetermined temperature by the heating means 34. After the preheating of the drying tank 30, the door 31a is opened and the waste 90 is charged into the drying tank 30 from the charging port 31 with the lid member 32b being lifted upward (charging process S1).

  After the completion of the charging, the door 31a is closed and the lid member 32b is placed on the waste 90, and the waste 90 is pressed toward the crushing member 32c by the weight of the lid member 32b. In this state, the crushing member 32c is rotationally driven by the driving means 37, and the waste 90 is crushed (crushing step S2). The crushed waste 90 falls from the plurality of holes formed in the crushing means 32 a and is retained in the retention part 33.

  The waste 90 that has been crushed and stayed in the staying portion 33 is heated and dried by the heating means 34 (drying step S3). This drying step S3 is performed while stirring the waste 90 that has accumulated by rotating the stirring means 36.

  The drying of the waste 90 is controlled by monitoring the temperature of the waste 90 itself detected by the temperature detection means 35 with a control means (not shown).

  FIG. 4 is a graph showing the change over time of the temperature detected by the temperature detecting means 35.

  As shown in FIG. 4, the temperature detected by the temperature detection means 35 is temporarily lowered when waste 90 having a temperature lower than the temperature of the preheated drying tank 30 is introduced (see t <b> 1). When the waste 90 contains water, part or all of the amount of heat applied to the waste 90 becomes latent heat of evaporation until the water in the waste 90 is completely evaporated. The temperature remains approximately 100 ° C. (see t1 to t3). Then, after the water contained in the waste 90 is completely evaporated (after the waste 90 is dried), the temperature of the waste 90 further exceeds 100 ° C. That is, while the moisture remains in the waste 90, the temperature of the waste 90 does not further increase beyond 100 ° C., and after the moisture of the waste 90 is completely evaporated (that is, after the waste 90 is dried). ) The temperature of the waste 90 further rises above 100 ° C.

The control means monitors the temperature detected by the temperature detection means 35, and the drying step S3 until the detected temperature (the temperature of the waste 90) further exceeds 100 ° C.
Continue. When the temperature of the waste 90 further rises above 100 ° C., specifically, when the temperature T1 exceeds 100 ° C. (for example, 110 ° C.) (see t3), the control means It is determined that the drying of 90 is completed. After determining that the drying of the waste 90 has been completed, the control means opens the door 39a and transfers the waste 90 dried by the transport conveyor 51 from the drying tank 30 to the sterilization tank 40 (transfer process S4). When the transfer of the waste 90 is completed, the door 39a is closed again, and the drying tank 30 and the sterilization tank 40 are isolated from each other.

  In the transfer step S4, the heating means 52 is driven so that the temperature of the waste 90 being transferred becomes a desired temperature.

  Next, in a state where the drying tank 30 and the sterilization tank 40 are separated from each other by the door 39a, the transferred waste 90 is brought to a sterilization temperature (temperature necessary for sterilization of the waste 90) in the sterilization tank 40. Until the waste 90 is sterilized (sterilization step S5).

  The sterilization step S5 is performed at a sterilization temperature (for example, about 120 ° C. to 200 ° C.) for a predetermined time (for example, about 10 minutes to several hours, typically about 10 minutes to 20 minutes) while stirring the waste 90 by the stirring means 41. ) By heating. Then, after the sterilization step S5 is completed, the door 44a is opened, and the sterilized waste 90 is taken out from the discharge port 44, whereby the sterilization process of the waste 90 is completed.

  In the present embodiment, heating of the waste 90 in the sterilization step S5 is performed by a heating means (for example, an electric heater) 42 disposed along the outer periphery of the sterilization tank 40. Waste 90 may be heated by blowing. Similarly, in the drying tank 30, the waste 90 may be heated by blowing hot air into the drying tank 30.

  Usually, since the sterilization temperature is a relatively high temperature such as 150 ° C. or higher, the waste 90 may be dissolved in the sterilization tank 40. For this reason, the temperature of the waste 90 in this sterilization step S5 is detected by the temperature detection means 43 arranged so as not to contact the waste 90, for example, without using the temperature detection means that directly contacts the waste 90. It is preferable to control based on the atmospheric temperature in the sterilization tank 40 to be used. Further, a radiation thermometer 46 that measures the temperature of the waste 90 itself in a non-contact manner may be used together with the temperature detection means 43 for detecting the ambient temperature, and the temperature of the waste 90 is controlled only by the radiation thermometer 46. May be.

  Further, as described above, since the normal sterilization temperature is a relatively high temperature, the waste 90 may ignite in the sterilization tank 40 when the atmosphere in the sterilization tank 40 is an air atmosphere containing oxygen. When the waste 90 is ignited and burned, there is a risk that harmful gases such as dioxins that cannot be trapped by a normal dust collection and deodorization apparatus 70 may be released into the atmosphere. For this reason, it is preferable that the sterilization process S5 performs the atmosphere in the sterilization tank 40 as a nonflammable gas atmosphere by driving the gas supply means 80. By doing so, it is possible to effectively suppress the release of harmful gases such as dioxins into the atmosphere.

  It should be noted that each time the drying step S3 is performed, the waste 90 dried by the single drying step S3 may be sterilized. However, from the viewpoint of sterilization work efficiency, the sterilization tank is used as in the present embodiment. The capacity of 40 is set to be larger than the capacity of the drying tank 30, the charging process S <b> 1 to the transfer process S <b> 4 are repeated a plurality of times, and the waste 90 for a plurality of times is once stored in the sterilization tank 40 and then the sterilization process. It is preferable to perform S5 collectively. By doing so, since the frequency | count of performing sterilization process S5 can be reduced, the energy cost which a sterilization process requires can be reduced. When the sterilization step S5 is performed every time the drying step S3 is performed, the sterilized waste 90 needs to be taken out from the sterilization tank 40 before the dried waste 90 is transferred next time. For this reason, it is necessary to separately provide a place for temporarily storing the taken-out waste 90. On the other hand, when performing the sterilization step S5 in a lump, the waste 90 can be temporarily stored in the sterilization tank 40 in a state before sterilization. There is no need to provide it separately.

  In order to increase the capacity of the drying tank 30, it is relatively difficult to provide a crushing means 32 a having a size corresponding to the capacity of the drying tank 30. Since the structure is relatively simple, the capacity can be expanded relatively easily. Further, by providing the drying tank 30 separately from the sterilization tank 40 and allowing the waste 90 dried in the sterilization tank 40 to be stored, the drying tank 30 can be made relatively small, so that it is relatively expensive and large. It is possible to reduce the size of the crushing means 32 that is difficult to reduce.

  As described above, the drying tank 30 separated from the sterilization tank 40 is provided separately from the sterilization tank 40, and the waste 90 dried in advance is put into the sterilization tank 40. It is possible to prevent the waste 90 containing moisture from being thrown in. For this reason, the temperature of the waste 90 conveyed to the sterilization tank 40 does not stay at around 100 ° C., but quickly rises to the sterilization temperature without delay. Further, since the amount of heat applied to the waste 90 does not become latent heat of evaporation, the temperature of the waste 90 can be stably maintained at the sterilization temperature. Therefore, the waste 90 can be sterilized reliably and effectively.

  In addition, when both the drying and sterilization of the waste 90 are performed in the sterilization tank 40 without separately providing the drying tank 30, the drying process S3 and the sterilization process S5 of the waste 90 cannot be performed at the same time. However, by separately providing the drying tank 30 as in the present embodiment, the drying step S3 and the sterilization step S5 of the waste 90 can be performed simultaneously. Therefore, for example, when the waste 90 having a capacity larger than the capacity of the drying tank 30 is processed or continuously processed, the waste processing apparatus 20 according to the present invention can be used to reduce the efficiency in a shorter processing time. Thus, the waste 90 can be sterilized.

  As described above, in the present embodiment, the control unit discards the waste in the drying tank 30 when the temperature of the waste 90 (strictly, the temperature detected by the temperature detection unit 35) further exceeds 100 ° C. It is determined that the drying of the object 90 has been completed. Then, the control unit determines that the drying of the waste 90 has been completed by the above-described method, and then transfers the dried waste 90 to the sterilization tank 40 by the transport conveyor 51. For this reason, for example, as in the case where the drying process is performed for a predetermined time at a predetermined temperature, the water-containing waste 90 is not transferred to the sterilization tank 40, and more reliable and efficient disposal. The product 90 can be sterilized.

  In addition, with such a method for determining the degree of drying of the waste 90, the end of drying is detected without delay when the drying of the waste 90 is completed, and it is possible to prevent the drying process from being performed unnecessarily. As a result, it is possible to sterilize the waste 90 quickly.

  In the present embodiment, the temperature of the waste 90 in the drying tank 30 is determined by the temperature detection means 35 of the drying tank 30 disposed so as to be in direct contact with the waste 90 in the drying tank 30. Since the temperature of 90 is detected, for example, by detecting the heater temperature in the drying tank 30, the temperature of the waste 90 is very accurately compared with the case where the temperature of the waste 90 is indirectly measured. The temperature of the waste 90 can be strictly measured.

  Moreover, by providing the crushing part 32 together with the staying part 33 in the drying tank 30 and crushing the waste 90 finely prior to the drying step S3, drying of the waste 90 is promoted, and the time required for drying the waste 90 is increased. It can be shortened. As a result, the time required for sterilizing the waste 90 can also be shortened. Further, by crushing the waste 90 prior to drying, the waste 90 can be uniformly dried without unevenness. Therefore, the mixing of moisture into the sterilization tank 40 can be more effectively suppressed. As a result, more reliable sterilization is possible.

  Furthermore, by rotating the stirring means 36 and heating the waste 90 staying in the staying portion 33 while stirring, the entire waste 90 can be heated uniformly, and the waste 90 can be heated in a shorter time. Can be reliably dried.

  Also in the sterilization step S5, by driving the stirring means 41 and heating the waste 90 while stirring, it becomes possible to uniformly heat the waste 90 to the sterilization temperature without unevenness, which is more reliable and efficient. Sterilization becomes possible.

  In addition, by disposing the waste treatment apparatus 20 on the vehicle as in the present embodiment, the waste can be sterilized at any place and at any time. For example, even in a medical facility that is relatively small and it is difficult to permanently install a treatment facility such as the waste treatment apparatus 20, the waste disposal vehicle 10 according to this embodiment can be used to dispose of in-hospital. It is possible to sterilize objects. In the waste treatment vehicle 10, since the capacity of the sterilization tank 40 is set larger than the capacity of the drying tank 30, the drying treatment in the drying tank 30 is performed a plurality of times, and the dried waste is stored in the sterilization tank 40. For example, sterilization can be performed collectively at the end of the day.

  For example, when the capacity of the drying tank 30 and the capacity of the sterilization tank 40 are substantially the same, each time the drying tank 30 is driven, the sterilization tank 40 is driven to perform sterilization, and then the drying tank It is necessary to take out the sterilized waste in the sterilization tank 40 from the sterilization tank 40 until the waste is transferred from 30. And it is necessary to store the processed waste separately in a space different from the sterilization tank 40. On the other hand, in the waste treatment vehicle 10 according to the present embodiment, the waste that has been sterilized collectively can be stored in the sterilization tank 40 as it is and transported from the hospital to the waste final disposal site. It becomes. That is, by using the waste treatment vehicle 10, it is possible to temporarily store sterilized waste and transport the treated waste to the final disposal site, depending on the total amount of waste, In some cases, it is not necessary to provide a separate storage site or transportation means.

  However, in the case where waste is sterilized in a large-scale medical facility where a large amount of medical waste is discharged, the waste treatment apparatus 20 may be permanently installed. Further, the waste treatment apparatus 20 may be arranged on a cart or the like so that the waste treatment apparatus 20 can be pulled and moved by an automobile or the like as necessary.

  As described above, in the present embodiment, an example in which the control unit is provided and the control unit determines that the drying of the waste 90 has been completed has been described. It may be determined that the drying of the waste 90 is completed by monitoring the temperature of the detection means 35.

  Moreover, although this embodiment demonstrated the example comprised so that the waste 90 dried using the conveyance conveyor 51 as a transfer means might be transferred to the sterilization tank 40, the conveyance conveyor 51 is necessarily essential structure. is not. For example, when the dried waste 90 is transferred by placing the drying tank 30 above the sterilization tank 40 and isolating the drying tank 30 and the sterilization tank 40 with a door or the like, the door is opened. Then, the waste 90 may be naturally dropped from the drying tank 30 and transferred to the sterilization tank 40.

  As described above, the present invention is useful for waste sterilization.

It is a side view showing the structure of a waste disposal vehicle. It is a schematic diagram showing the structure of a waste disposal apparatus. It is a flowchart of the waste processing performed in a waste processing apparatus. It is a graph showing the time-dependent change of the temperature detected by a temperature detection means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Waste disposal vehicle 20 Waste disposal apparatus 30 Drying tank 32 Crushing means 33 Retention part 34, 42, 52 Heating means 35, 43 Temperature detection means 36, 41 Stirring means 40 Sterilization tank 51 Conveyor 80 Gas supply means 90 Waste

Claims (18)

A waste treatment apparatus for heating and sterilizing a waste by dry heat,
A drying tank for heating and drying the waste,
A sterilization tank isolated from the drying tank, which heats and sterilizes the waste material dried in the drying tank;
After judging that the waste is dried based on the physical quantity change related to the waste in the drying tank, and judging that the waste in the drying tank is dried, the waste in the drying tank is removed from the sterilization tank. Control means for restricting the transfer of the waste in which moisture remains to the sterilization tank ;
Waste disposal device with The waste treatment apparatus according to claim 1,
The waste treatment apparatus, wherein the control means determines that the waste is dried when the temperature of the waste in the drying tank further exceeds 100 ° C. The waste disposal apparatus according to claim 1 or 2,
Disposal characterized by further comprising temperature detection means for the drying tank installed in the drying tank, wherein the control means detects the temperature of the waste in the drying tank by the temperature detection means of the drying tank. Material processing equipment. The waste treatment apparatus according to any one of claims 1 to 3,
The said drying tank is equipped with the crushing means which crushes the said waste, the retention part which retains the said crushed waste, and the heating means of the drying tank which heats the said retention part, The disposal characterized by the above-mentioned Material processing equipment. In the waste disposal apparatus according to claim 4,
The drying tank further includes a drying tank stirring means for stirring the staying waste when the staying waste is heated and dried by the heating means of the drying tank. A waste treatment apparatus characterized by that. In the waste disposal apparatus according to any one of claims 1 to 5,
The waste sterilization apparatus is characterized in that the capacity of the sterilization tank is larger than the capacity of the drying tank. The waste disposal apparatus according to any one of claims 1 to 6,
A waste treatment apparatus, further comprising gas supply means for supplying a noncombustible gas into the sterilization tank when the waste is heated and sterilized in the sterilization tank. The waste disposal apparatus according to any one of claims 1 to 7,
A waste treatment apparatus, further comprising a sterilization tank heating means for heating the sterilization tank. The waste disposal apparatus according to any one of claims 1 to 8,
The apparatus further comprises a sterilization tank temperature detecting means for detecting an ambient temperature in the sterilization tank, and the control means controls the temperature of the waste in the sterilization tank based on the temperature detected by the temperature detection means of the sterilization tank. Waste treatment equipment that is to be. The waste disposal apparatus according to any one of claims 1 to 9,
The said sterilization tank is equipped with the sterilization tank stirring means for stirring the said waste, when heating and sterilizing the waste in the said sterilization tank, The waste processing apparatus characterized by the above-mentioned.   A vehicle equipped with the waste disposal apparatus according to any one of claims 1 to 10. A waste disposal apparatus comprising: a drying tank for heating and drying waste; and a sterilization tank isolated from the drying tank for sterilizing by dry heat by heating the waste dried in the drying tank. A method of treating waste using:
A charging step of charging waste into the drying tank;
A drying step of heating and drying the charged waste;
In the drying step, it is determined that the waste in the drying tank is dried based on a change in physical quantity related to the waste in the drying tank, and the waste in which moisture remains is transferred to the sterilization tank. A decision process that regulates
A sterilization step of dry heat sterilization by heating the waste determined to be dry in the sterilization tank;
Waste disposal method comprising: The waste disposal method according to claim 12, wherein
The waste determination method is a waste processing method in which the waste in the drying tank is determined to be dry when the temperature of the waste in the drying tank further rises from 100 ° C. The waste treatment method according to claim 12 or 13,
Prior to the drying step, the waste treatment method further comprises a crushing step of crushing the waste. The waste disposal method according to any one of claims 12 to 14, wherein
The method for treating waste, wherein the drying step is performed while stirring the waste. The waste treatment method according to any one of claims 12 to 15, wherein:
A waste treatment method comprising performing the sterilization step collectively on wastes dried by the plurality of drying steps after performing the charging step and the drying step a plurality of times. The waste disposal method according to any one of claims 12 to 16, wherein
The waste sterilization step is performed as a non-combustible gas atmosphere in the sterilization tank. The waste disposal method according to any one of claims 12 to 17,
The waste sterilization process is performed while stirring the waste in the sterilization tank.

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