KR100267141B1 - Dry processing of food waste and its apparatus - Google Patents

Abstract

PURPOSE: Provided are a method for processing food wastes by compressing, pulverizing and multistage drying the wastes and the apparatus, which can serve stabilized state of well dried wastes stored and carried easily and used as fuel in an incinerator or auxiliary feed and fertilizer. CONSTITUTION: The method includes the following steps of: (i) feeding food wastes stored in a bunker and pulverizing the wastes before dehydrating leachate from the pulverized wastes and dispersing the solid state of dried food wastes; (ii) removing metallic debris particles from the dispersed wastes and discharging a fixed quantity of the sorted wastes continuously to a preheating device; (iii) preheating the quantitative discharged wastes with steam heat to critical water content and removing to a first screw dryer through a screw conveyor(32) for dehydrating the wastes with steam heat and dried hot air; (iv) redrying the wastes in a second screw dryer and finally drying the wastes in a rotary dryer; (v) removing metallic debris particles from the dehydrated wastes again and remaining debris particles by vibrating the wastes; and then (vi) compressing and forming the resulting waste materials into a fixed sized body. The apparatus comprises a hopper(18), a pulverizer(20) connected to a motor and a reduction device and composed of two parallel rotating cutters with a plurality of hooks on the surface, a dehydrator(20), a dispersion device(24), a rotating drum type of magnetic sorting machine(26), a quantitative discharge hopper and a quantitative supply feeder, a preheater(16), a first and a second screw drying devices(10,12) composed of a motor operating a couple of screws without axis and a steam heat and a dried hot air supply devices, a drum type of rotary drying device(14), a belt removing type of magnetic sorting machine(27), a compression forming device(38), and a suction type of deodorizing device(40).

Description

Method and apparatus for drying food waste

The present invention relates to a food waste drying treatment method and apparatus, and more particularly, to a food waste including odor and leachate, such as a compression / crushing process, a drying process divided into a multi-stage sequence, and at the same time steam heat and drying hot air. The present invention relates to a food waste drying treatment method and apparatus for supplying food waste to be easily dried.

In general, food waste refers to food waste discharged from restaurants, homes, and catering establishments, and agricultural, water, and livestock waste generated during the production, distribution, processing, and cooking of food, and most of the food waste components. Is composed of leachate, water, etc., which is accompanied by a severe odor.

Currently, the disposal of food wastes discharged as described above is mostly landfilled in landfills containing leachate, etc., so that the leachate of the landfilled food waste is absorbed into the landfill soil, causing severe odor and polluting the soil. .

As a result, a sanitary landfill was installed on the bottom surface to allow leachate, such as food waste, to flow to a certain reservoir, but leachate flows through the embankment around the curtain and flows into nearby rivers. If polluting hazards are generated and food waste is left untreated in rivers and mountains instead of in landfills, environmental pollution is further increased.

In addition, although the policy to use food waste as a resource, that is, composting, feed, and fuel is being implemented, the following problems have occurred.

When the food waste is put into a composting container for fermentation and used as a plant compost, the fermented food waste contains salt and heavy metals as it is, which causes harm to plants.

Although the plant was established to feed food waste for the feed, the wastewater was generated according to the food waste feed process, and the measurement of BOD and COD of the waste water was 2000ppm and 1000ppm, which exceeded the allowable limit of 120ppm by up to 17 times, respectively. This resulted in the increase of environmental pollution, and it was not suitable because it contained salinity to feed livestock food waste to livestock.

For the fuelization, once the household waste containing food waste is incinerated by incineration, the moisture of the food waste lowers the incineration temperature, and when incinerated, harmful components such as dioxins are generated. In addition, although the amount of food waste can be reduced by using the apparatus for reducing food waste, there was a limit in reducing food waste only by the function of simple compression in which water is not completely removed.

As described above, the problem caused by the leachate of food waste is very serious. To solve this problem, the food waste containing a large amount of leachate must first be dried. The reason for this is that drying removes leachate and residual water, including the salinity of food waste, the ultimate source of contamination.

Therefore, it is easy to landfill without contamination of leachate, can be used as raw material and compost of compound feed, and since the food waste is dried, it improves the combustion conditions of the incinerator that incinerates and fuels the food waste and dioxin. It can reduce the harmful gas such as and increase the amount of heat generated.

Accordingly, there is an urgent need for an efficient food waste drying method and apparatus for drying the food waste.

The present invention devised a method and apparatus for drying food waste in order to solve the harm caused by food waste as described above, to dry the food waste once the food waste containing water, such as leachate and tangled Firstly, the first screw dryer and the second preheater supplied with steam heat and the steam heat and drying hot air are simultaneously supplied by removing foreign substances such as metal pieces contained in the food waste after grinding and compacting to dehydrate the leachate. It is an object of the present invention to provide a method for treating and drying a food waste in a compression / pulverization and multi-stage drying method that allows food waste to be dried by passing through a screw dryer and a rotary dryer in order.

1 is a process chart showing the food waste drying treatment process and the installation state of the apparatus according to the present invention,

2 is a flowchart of a food waste drying treatment process according to the present invention;

3 is a plan view showing the entire installation state of the food waste drying apparatus according to the present invention,

4 is a cross-sectional view showing an overall installation state of the food waste drying apparatus according to the present invention;

Figure 5 is a graph showing the relationship between the moisture content and drying rate when steam heat and drying hot air is supplied to the food waste drying apparatus according to the present invention preheating and drying.

<Description of the code | symbol about the principal part of drawing>

10: first screw dryer 12: second screw dryer

14: Rotary dryer 16: Preheater

18: hopper 20: crusher

22: dehydrator 24: disperser

26: rotating drum type magnetic separator 27: belt transfer type magnetic separator

28: quantitative discharge hopper 30: quantitative supply avoid

32: screw conveyor 34: apron conveyor

36: vibration screen 38: compression molding machine

40: Deodorizer 42: Bunker

44: overhead crane 46: bucket

48: Input gate 50: Screw without a shaft

52: rotary feeder 54: two-stage housing

56a, 56b: Supply piping line 57: 3-stage housing

58: rolling guide 60: first blower

61: second blower 62: first heat exchanger

63: second heat exchanger 64: steam heat of the incinerator

65: incinerator 66a, 66b: discharge piping line

68: oil burner 70: biofilter layer

72: condenser

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

Food waste drying treatment method of the present invention is a step of feeding the food waste stored in the bunker 42 of a predetermined size into the input hopper 18 using the overhead crane 44 and the bucket 46, and the input hopper Dispersing the food waste put into the (18) in the crusher 20, and dehydrated leachate of the crushed food waste in the dehydrator 22 and dehydrated and compressed food waste in the solidified state in the disperser (24) And the step of removing the metallic foreign matter in the dispersed food waste in the rotary drum type magnetic separator 26, and feeding the removed food waste into the metering discharge hopper 28 for continuous quantitative discharge. To quantitatively transfer the food waste discharged in a fixed amount from the metered discharge hopper 28 to the preheater 16 via a metered supply feeder 30. And preheating the food waste transported into the preheater 16 with steam heat supplied by the steam heat supply means so as to have a critical moisture content, and passing the preheated food waste through the screw conveyor 32 to the first screw dryer. (10) and then drying the food waste by the steam heat and dry hot air supplied by the steam heat supply means and the dry hot air supply means, and screw the food waste spilled out of the first screw dryer (10) After passing through the conveyor 32 into the second screw dryer 12, the step of drying again with the steam heat and the drying hot air, and the food waste discharged from the second screw dryer 12, the screw conveyor 32 Transporting the resultant to the rotary dryer 14 via a gas furnace, followed by final drying with the steam heat and the drying hot air, and the rotary dryer 14 The food waste discharged from) is transferred to the belt conveying type magnetic separator through the screw conveyor 32 and the apron conveyor 34 in order, and then the metal foreign matter is removed again, and the foreign matter is removed again. The food waste is passed through the screw conveyor 32 and simultaneously transferred to the vibrating screen 36 to release the tangled state by vibration, and the food waste discharged from the vibrating screen 36 is transferred to the compression molding machine 38. It is characterized in that it comprises a step of compression molding to be put into a molded body of a predetermined size, and a step of transporting the food waste in the dry state compression-molded to the predetermined size to a predetermined place.

In addition, the first screw dryer 10 so that the odor of the food waste generated during the drying process of the food waste passing through the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 in turn is removed. Deodorizer 40 is connected to the second screw dryer 12 and the rotary dryer 14 by a pipe line, and the process of removing odor is simultaneously performed.

The food waste drying apparatus of the present invention includes a grinder 20 consisting of an input hopper 18 into which food waste is input, two parallel rotary cutters each having a plurality of hooks protruding from the motor and a reducer and protruding from the surface thereof. And a dehydrator 22 having a housing having a feeding section and a screw portion having a feed screw for compressing / dehydrating and transporting food waste, and a discharge portion, and rotatable inside to disperse compressed and dehydrated food waste. Disperser 24 equipped with an impeller braid, a rotary drum type magnetic separator 26 composed of a permanent magnet part and a drive motor to remove metallic foreign substances in food waste, and a fixed-quantity rotary valve to quantitatively discharge food waste. The quantitative discharging hopper 28 and the quantitative feeding feeder 30 for quantitative delivery and the two-stage housing 54 of a predetermined size A pair of parallel shaftless screws 50 are installed in two stages, and a pre-heater 16 for preheating food waste is installed by connecting a drive motor and steam heat supply means, and a top and bottom three in a three-stage housing 57 of a predetermined size. However, a first screw dryer in which a pair of parallel shaftless screws 50 are internally installed, and a drive motor for driving the shaftless screws 50 in rotation, and a steam heat supply means and a dry hot wind supply means are installed side by side. 10) and a drum type rotary dryer (14) equipped with a second screw dryer (12), a drive motor, steam heat supply means, a dry hot wind supply means, and an oil burner (68), and from the rotary dryer (14). A belt transfer type magnetic separator (27) for removing metal foreign matters from the discharged food wastes again, a vibrating screen (36) equipped with a vibrator on the bottom to vibrate and disperse the food wastes in the dried and entangled state; Compression molding machine 38 for compression molding the used food waste to a predetermined size, and to remove the odor of the food waste generated in the first screw dryer 10, the second screw dryer 12 and the rotary dryer 14 It is characterized by consisting of a suction type deodorizer 40 is installed in turn.

In particular, food waste is disposed between each of the preheater 16, the first screw dryer 10, the second screw dryer 12, the rotary dryer 14, the belt transfer type magnetic separator 27, and the vibration screen 36. As a conveying means, the screw conveyor 32 in which the conveying screw was built is provided.

Preferably, an apron conveyor 34 is installed between the screw conveyor 32 connected to the discharge part of the rotary dryer 14 and the belt transfer type magnetic separator 27.

In addition, the steam heat supply means simultaneously connected to the preheater 16, the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 by a steam heat supply pipe line 56a is preferably an incinerator. 65 is the incineration vapor heat 64.

In addition, the first blow dryer, which is connected to the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 by a dry hot air supply pipe line 56b, is preferably connected in turn. 60 and the first heat exchanger 62, the second blower 61, and the second heat exchanger 63.

The second heat exchanger 63 is simultaneously connected to the drying hot air supply pipe line 56b of the first and second screw dryers 10 and 12 and the rotary dryer 14.

In addition, the second heat exchanger (63) is connected to the incineration steam stream (64) to receive heat, and a first installed between the first blower (60) and the second blower (61) to discharge the used heat. The first heat exchanger 62 is connected to the incinerator 65 so that the heat used in the first heat exchanger 62 is discharged back to the incinerator 65.

Meanwhile, the incineration steam heat 64 of the incinerator 65 supplied to the preheater 16, the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 again incinerates 65. A discharge pipe line 66a connected to the incinerator 65 is installed to exit the furnace.

In addition, the first blower 60 heat-exchanged by the first heat exchanger 62 and the second heat exchanger 63 in the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14. And a first heat exchanger 62 and a deodorizer 40 to be supplied to the first heat exchanger 62 and the deodorizer 40 after the dry hot air of the second blower 61 is supplied and moistened with air. Is connected to the discharge pipe line 66b.

Preferably, the discharge pipe line 66a has a bifurcation discharge pipe line in which 90% of the wet air is discharged to the first heat exchanger 62 and 10% of the wet air is discharged to the deodorizer 40. (66b).

More preferably, a condenser 72 including a cooling device is installed between the deodorizer 40 and the discharge pipe line 66b, and the moisture of the condensed wet air is a sewage treatment plant, and the odorous air from which the water is removed is a deodorizer. Exit to (40).

On the other hand, in order to prevent the formation of bridges during the input of food waste, the hopper portion of the input hopper 18 and the crusher 20 is formed asymmetrically and is formed in a wide cross section.

The pressure screw installed in the cylindrical housing having a constant cross-sectional area of the dehydrator 22 and rotated by the drive motor has a shape in which the cross-sectional area gradually increases with respect to the traveling direction of the food waste.

The oil burner 68 mounted to the rotary dryer 14 may replace the incineration steam train 64 of the incinerator.

A bunker 42 of a predetermined size into which food waste before being fed into the feeding hopper 18 is stored is installed adjacent to the feeding hopper 18.

As a means for feeding and transporting the food waste stored and stored in the bunker 42 to the feeding hopper 18, an overhead crane 44 having a bucket 46 is transportably mounted above the bunker 42. .

In addition, a bio filter layer 70 for filtering odors of food waste is installed on the roof layer of the equipment factory in which the food waste drying apparatus is installed.

In addition, a system control room that can be controlled for each device is installed to control the food waste drying treatment device.

The present invention will be described in more detail as follows.

1 is a process chart showing the food waste drying treatment process and the equipment state of the apparatus according to the present invention, and reference numeral 42 is a bunker in the food waste drying treatment plant.

First, the food waste is introduced into the processing plant and stored in the bunker 42. The inlet passage entrance of the drying processing plant in which the food waste is carried in the air curtain prevents the odor of the food waste from escaping the processing plant. An air curtain is installed, and the entrance inside the entrance is a space that only the vehicle can enter.

A food waste input gate 48 is provided between the entrance space of the carry-on vehicle and the bunker 42, and the food waste of the loaded vehicle is introduced into the bunker 42 through the input gate 48. .

The bunker 42 is a molded body having a predetermined depth having an upper surface open, and the wall surface of the side into which the food waste is input is formed to be inclined downward so that the food waste can be easily introduced.

In addition, a sewage reservoir is installed under the bottom of the carry-on and bunker 42, and a line communicating with the sewage reservoir is formed at the bottom of the bunker 42 so that the leachate of food waste flows easily into the sewage reservoir. Lose.

At this time, an overhead crane 44 to which the bucket 46 is transportably connected is installed above the upper opening of the bunker 42.

Therefore, using the bucket 46 of the overhead crane 44, the food waste in the bunker 42 is introduced into the feed hopper 18, which is the first input of food waste in the food waste drying apparatus.

The input hopper 18 is a symmetrical hopper 18 formed with a gentle slope on which the bucket 46 is conveyed, and the opposite side is formed in a substantially vertical shape, which means that the food waste of the bucket 46 is out of the hopper. In order not to be separated, and also as the cross-sectional area from the upper input portion to the lower discharge portion is a shape that is larger, this is to prevent the stacking of the food waste in the piers.

Next, the food waste discharged downward from the input hopper 18 is subjected to a grinding process.

The crusher 20 is installed under the discharge portion of the lower end of the hopper 18, the upper side of the crusher 20 coincides with the discharge portion of the hopper 18 is formed a hopper portion for receiving food waste Inside, two rotary cutter shafts, each of which has a plurality of protruding hooks, are installed facing each other in parallel, and a drive motor and a reducer for driving the rotary cutter shafts are provided on one side.

In addition, the crusher 20 is provided with an overload safety device, the overload safety device is the two rotary cutters by the electric control when the crushing capacity is exceeded due to the foreign matter of the food waste put into the reverse rotation and then rotates again. In the case of continuous reverse and forward rotations, a non-crushing signal is sent to the system control room.

Accordingly, the food waste discharged from the hopper 18 is introduced into the hopper of the grinder 20 and is crushed by the internal rotary cutter. The food waste is pulled by the shear force, the compression force, and the friction force between the rotary cutter and the rotary cutter. Pulling and grinding.

On the other hand, the crushing particle size of the food waste in the grinder 20 is determined according to the thickness of the rotary cutter and the number of hooks protruding integrally from the surface of the rotary cutter.

Next, the food waste pulverized in the grinder 20 is a state in which the leachate continues to contain the leachate, which requires a process of removing the leachate.

The dehydrator 22 is installed just below the grinder 20.

The dehydrator 22 has a cylindrical housing having a predetermined cross-sectional area, and the upper part of the housing is provided with an inflow hopper part into which food waste pulverized from the grinder 20 is introduced, and a lower part of the dehydrator 22 is discharged. An additional portion is formed therein, and a cylindrical pressure screw portion having a larger diameter, that is, a larger cross-sectional area, is built in from the inflow hopper to the discharge portion.

In addition, a drive motor for rotationally driving the cylindrical pressure screw is installed on one side of the housing outside of the dehydrator 22, and the feed screw is periodically disposed on the surface of the screw so that the food waste is easily transferred from the hopper to the discharge part. It is integrally formed, and a filter is mounted obliquely at the bottom of the mill, i.e., under the screw, and an outlet through which the dewatered leachate flows out to the sewage storage is formed at the end thereof, immediately next to the discharge part.

Therefore, the food waste introduced from the grinder 20 is transferred to the discharge portion between the pressure screw and the housing and is pressurized so that the leachate is dehydrated.

More specifically, the gap between the pressurizing screw and the housing becomes narrower toward the discharge portion, so that the food waste is pressurized and the leachate is dehydrated, and the dehydration liquid is discharged to the dehydration outlet, and the dehydrated food waste is the feed screw. It is discharged to the discharge part by the feed force of.

Next, since the food waste dewatered and discharged from the dehydrator 22 is pressurized and dehydrated, the food waste is solidified by pressing force, and a process of dispersing the solidified state of the food waste is required.

Accordingly, a disperser 24 for dispersing food waste dehydrated in the dehydrator 22 is installed directly under the dehydrator 22.

The disperser 24 has a form in which an impeller braid rotated at high speed by a driving motor is installed.

Therefore, the solidified food waste introduced from the dehydrator 22 is introduced into the disperser 24 and is dispersed by the rotation of the impeller braid.

Next, the food waste dispersed in the disperser 24 is a state in which a large amount of metallic foreign matter is contained, and a process of removing the foreign matter is required.

Thus, a rotary drum type magnetic separator 26 for removing the metallic foreign matter is installed directly under the disperser 24.

The rotating drum type magnetic separator 26 has a drum rotating therein by a drive motor therein, and a permanent magnet is attached to the drum.

Therefore, the food waste introduced from the disperser 24 flows into the drum in the rotary drum type magnetic separator 26, and the food waste is also rotated at the same time as the drum rotates, and metallic foreign matter on the food waste adheres to the permanent magnet. Removed.

Next, the food waste discharged by removing the foreign matter from the rotary drum type magnetic separator 26 is introduced into the quantitative discharge hopper 28 installed directly below the magnetic separator 26.

The quantitative discharge hopper 28 is provided with a transfer device to prevent the food waste that is continuously introduced from the rotary drum type magnetic separator 26 to form a sharp pier and accumulate therein, the discharge portion of the lower drive The rotary valve which drives rotation by a motor is provided.

Therefore, the food waste continuously introduced from the rotary drum type magnetic separator 26 into the quantitative discharge hopper 28 is always discharged quantitatively by the rotary valve.

Next, the food waste discharged from the metered discharge hopper 28 is transferred to the metered feed feeder 30 installed in a vertical direction with the discharge portion.

The feed meter feeder 30 has a feed screw having a feed force therein, a drive motor for rotating the screw is installed on one side, the inlet for food waste from the metered discharge hopper 28 On the opposite side thereof, a vertical outlet portion is formed.

Therefore, the food waste introduced from the metered discharge hopper 28 changes the feed rate according to the rotational speed of the feed screw of the metered feed feeder 30 and always transfers the food waste of a fixed amount.

On the other hand, the food waste transported through the metered feed feeder 30 and leaked to the outflow portion contains the leachate and odor that has not been completely removed yet, from which the substantial drying treatment process of the food waste proceeds.

The outlet of the metered feed feeder 30 is connected to the preheater 16.

The preheater 16 is a rectangular body and includes a heat insulating material, and the two-stage structure housing 54 divided up and down inside forms an outline, and each space in each of the two-stage housing 54 divided up and down two stages has two spaces. Rolling guide 58 having a shape in which two semicircle plates are integrally connected in parallel is formed over the longitudinal direction of the two-stage housing 54 to form an upper and lower sealed space, and is connected to the outlet of the metered feed feeder 30. And an inflow hopper portion for receiving food waste is formed on an outer one side of the housing 54.

Here, a pair of shaftless screws 50 are inserted into the rolling guides 58 formed in each of the two-stage housings 54 so as not to be in close contact with the rolling guides 58. A driving motor for rotating the shaftless screw 50 is mounted on one side of the second stage housing 54.

In addition, the food waste is conveyed by the pair of shaftless screws 50 at one side of the upper end of the inlet hopper part of the two-stage housing 54, that is, the opposite side of the inlet hopper part to be transported to the shaftless screw 50 at the lower end thereof. The rotary feeder 52 is built-in, and the outflow part is formed in the end with respect to the conveyance direction of the screwless shaft 50 of the lower end of a two-stage housing.

In addition, the upper and lower ends of the two-stage housing 54 of the preheater 16, the supply pipe line 56a for supplying the incineration steam heat 64 generated from the incinerator 65 is sealed below the rolling guide 58. It is connected and fitted to match the internal space, and the discharge pipe line 66a connected to the incinerator 65 is mounted on the opposite side of the supply pipe line 56a.

On the other hand, incineration steam heat 64 of the incinerator 65 is a discharge pipe line 66a as a means for supplying steam heat to the first and second screw dryers 10, 12 and the rotary dryer 14, which will be described later. Are connected simultaneously.

Therefore, the food waste introduced from the metered feed feeder 30 is introduced into the screw 50 without the upper shaft of the preheater 16 to start feeding toward the rotary feeder 52, and the rotary feeder 52 again. The lower shaft is conveyed to the screw 50 without, and continuously transported along the lower shaft without the screw 50 is discharged to the outlet.

At this time, the incineration vapor stream 64 generated in the incinerator 65 is supplied to the closed space under the rolling guide 58 in the two-stage housing 54 of the preheater 16 via the supply pipe line 56a. The supplied incineration steam heat is conducted to the food waste which is constantly transported along the unscrewed screw 50 which rotates in the upper sealed space of the rolling guide 58 in the preheater 16 so that the food waste is preheated. The steam heat 64 of the incinerator, which preheats the food waste, exits to the incinerator 65 to be recycled via the discharge pipe line 66a.

On the other hand, it is preferable that the preheating degree of the food waste preheated by the preheater 16 is preheated to a critical water content rate.

With reference to the accompanying Figure 5 will be described in more detail with respect to the food waste to reach the critical function rate as follows.

The most commonly used method of removing water from food waste is drying, which applies heat energy to the material to evaporate the moisture and converts it to a dry form. In other words, drying is a method of evaporating and removing moisture in an object using heat.

Water must transfer about 600 Kcal of heat per kilogram of water containing water to the object in order to convert it into water vapor. Therefore, it is necessary to find an appropriate transfer method and to consider the temperature and heating time related to it to achieve the most efficient heat transfer for the object to be dried.

As shown in FIG. 5, the drying process is divided into three sections: a material preheating period, a constant drying period, and a rate reduction drying period. The material preheating period is a temperature at which a material mixed with water starts to evaporate smoothly. The time it takes to reach is short in time, and during this time evaporation hardly takes place, so the change in moisture content is small.

The constant drying period is a period in which moisture is evaporated as much as heat is transferred to an object while maintaining a constant temperature, and the heat transfer rate from the surroundings and the evaporation rate from the material are in an equilibrium state, and the temperature of the material is approximately hot air. The rate of drying of the material during this term drying period is always constant, and the time point at which the term drying period ends is referred to as the critical moisture content.

In general, when the material has a lot of contact with hot air, such as a fluidized bed drying or airflow drying method, or the material is smallly divided, and the contact area with the hot air is large, drying is performed efficiently. As this decreases, the moisture transfer resistance inside the material increases, and the drying speed decreases. This period is referred to as the rate of drying period.

Therefore, the food waste derived after the preheating in the preheater is preheated to the above-mentioned critical water content.

Next, the food waste preheated as described above is transferred to the first screw dryer 10, and the drying process of the first screw dryer 10, which proceeds to the rate reduction drying period, is performed.

At this time, the food waste in the preheated state is discharged to the outlet of the preheater 16 is transferred to the first screw dryer 10 via the screw conveyor 32.

The first screw dryer 10 has a three-stage housing 57, which is finished with a heat insulating material and is divided into three stages of upper and lower sides, and has an outer hopper, and an inflow hopper unit for receiving food waste of the three stage housing 57. It is formed on the upper one side.

In addition, in the uppermost inner space of the housing 57 divided into three stages, a rotational transfer part 52 is formed at a position opposite to the inflow hopper part, which leads to an intermediate space. The rotation conveyance part 52 is formed, and the outflow part is formed in the opposite side.

In addition, each of the three-stage housing (57) is equipped with the rolling guide 58 of the shape in which the two semicircle plates are integrated in parallel to form an upper and lower sealed space throughout the longitudinal direction of the housing, without a shaft Screw 50 is not in close contact with the semicircle of the rolling guide 58 is installed rotatably inserted

In this case, a drive motor is mounted at an outer portion of the three-stage housing 57 to rotate the shaftless screw 50, and a closed lower space of each rolling guide 58 of the three-stage housing 57 is provided. And a supply pipe line 56a to which the incineration steam heat 64 of the incinerator 65 is supplied and a discharge pipe line 66a connected to the incinerator 65 are connected to the housing surface corresponding to each other. A supply pipe line 56b for supplying dry hot air is connected to the three-stage housing 57 surface corresponding to the upper sealed space of the shaftless screw 50 and a discharge pipe line 66b for discharging the dry hot air on the opposite side thereof. ) Is mounted connected.

On the other hand, when explaining the source and discharge of the dry hot air as follows.

As shown in the accompanying FIG. 2, the supply source of the dry hot air comprises a first blower 60, a first heat exchanger 62, a second blower 61, and a second heat exchanger 63. The second heat exchanger 63 is simultaneously connected to the preheater 16 and the supply pipe line 56b of the first and second screw dryers 10 and 12. Accordingly, the first blower 60 sucks outside air, and at the same time, the sucked air flows into the first heat exchanger 62 to complete heat exchange, and then is sucked into the second blower 61. And continuously flows into the second heat exchanger 63 to be heat exchanged again to become a final drying hot air, which is supplied to the supply pipe line 56b and at the same time the first and second screw dryers. 10, 12 and the rotary dryer 14 are supplied.

More specifically, the circulation of the exchange heat supply circulation of the first heat exchanger 62 and the second heat exchanger 63 and the drying hot air heat exchanged are performed as follows.

The steam heat 64 of the incinerator for supplying steam heat to the preheater 16 and the first screw dryer 10 is simultaneously connected to the second heat exchanger 63 and supplied to the second heat exchanger 63. The heat from the heat exchange with respect to the hot air supplied by the second blower 61 in 63 is connected to be supplied to the first heat exchanger 62 again, and the first heat exchanger 62 receives the first heat exchanger. The heat released after the heat exchange with the external air supplied by the blower 60 is circulated again to be supplied to the incinerator 65 again.

In addition, the discharge of the dry hot air supplied from the second heat exchanger (63) into the first screw dryer (10) follows the first heat exchanger (62), the deodorizer (40) and the discharge pipe line (66b). It is discharged to the connected condenser 72.

Therefore, the food waste conveyed by the screw conveyor in the preheater 16 is introduced into the inlet hopper of the first screw dryer 10 to provide the shaftless screw 50 installed in the uppermost space in the three-stage housing 57. Along with the axisless screw 50 of the intermediate space via the rotary feeder 52 at its end and likewise along with the axisless screw of the lowest space via the rotary feeder 52 at its end. It is conveyed along 50 and exits to the outlet at its end.

At this time, the food waste being transported as described above in the first screw dryer 10 is an enclosed space under the rolling guide 58 that surrounds each of the shaftless screws 50 along the supply pipe line 56a. At the same time as the steam heat 64 of the incinerator is supplied to the drying hot air supplied in a convective orthogonal flow to the space above the shaftless screw 50 along the supply pipe line 56b is directly contacted and dried .

Subsequently, the dry hot air finished drying the food waste contains wet steam, and 90% of the dry hot air is supplied to the first heat exchanger 62 via the discharge pipe line 66b, and 10% of the condenser And condensed at 72) to the deodorizer (40).

Next, after finishing the drying process of the first screw dryer 10 as described above, the food waste spilled to the outlet part is again subjected to the drying process of the second screw dryer 12 via the screw conveyor 32.

The second screw dryer 12 has the same construction and drying operation process as that of the first screw dryer, and thus, the food waste is subjected to the drying process of the second screw dryer 12 such as the drying process of the first screw dryer 10. Going through.

Here, the food waste having been dried in the second screw dryer 12 is transferred into the rotary dryer 14 via the screw conveyor 32 to undergo the drying process of the rotary dryer 14.

The rotary dryer 14 has a drum-shaped housing and an inlet portion at an upper side of the drum-shaped housing so as to receive food waste transported from the second screw dryer 12, and an outlet portion at the opposite side thereof. For example, a speed reducer is mounted to control the rotation speed and the motor for driving the rotation 14.

In addition, a supply piping line 56a for receiving the incineration steam heat 64 of the incinerator and a supply piping line 56b for receiving the drying hot air are connected to a predetermined portion, and a discharge piping line 66b through which the drying hot air escapes is also connected. It is connected to a predetermined portion opposite to the supply pipe line 56b.

Similarly, the source of incineration steam heat and the drying hot air of the rotary dryer 14 are the same as those of the first and second screw dryers 10 and 12, and the drying hot air discharged along the discharge pipe line 66b. The final discharge is also the first heat exchanger 62 and the condenser 72 connected to the deodorizer 40, similarly to the first and second screw dryers 10, 12.

On the other hand, one side of the rotary dryer 14 is provided with an oil burner 68, in case the supply state of the incineration steam heat 64 of the incinerator supplied to the rotary dryer 14 is unstable Burner 68 is installed.

Therefore, the food waste conveyed from the second screw dryer 12 is introduced into the rotary dryer 14, thereby adjusting the rotational speed of the rotary dryer 14 so that the introduced food waste reaches an equilibrium moisture content. The drying is carried out, and the drying hot air after drying the food waste is discharged to the condenser 72 connected to the first heat exchanger 62 and the deodorizer 40.

The equilibrium moisture content is different from the critical water content, that is, even when the material in the critical water content state is dried, it has a constant water content which finally indicates the water retention state peculiar to the material, which is referred to as the equilibrium water content. Therefore, the moisture that can be removed when the drying conditions such as temperature, humidity, etc. are determined in drying a material is up to parallel moisture content.

As mentioned above, the food wastes which have completed the drying process of the rotary dryer 14 are dried to the equilibrium moisture content, and are finally in a dried state.

Next, the food waste spilled from the rotary dryer 14 is transferred to the belt transfer type magnetic separator 27 by the screw conveyor 32 and the apron conveyor 34 to undergo a foreign material removal process such as metal material again.

The belt transfer type magnetic separator 27 is a device for removing the foreign matter firstly removed from the previous rotary drum type magnetic separator 2 6, and a belt conveyor unit and a driving unit for continuously rotating the belt conveyor unit; It consists of a permanent magnet part.

Therefore, the food waste conveyed from the rotary dryer 14 via the screw conveyor 32 and the apron conveyor 34 is once again passed through the belt transfer type magnetic separator 27 and foreign matters such as a bottle cap are introduced into the food waste. Removed.

Next, the food waste from which the foreign matter is removed as described above is transferred to the normal vibration screen 36 via the screw conveyor.

The vibrating screen 36 is a vibrator installed on the bottom to disperse the tangled material by vibrating to separate the foreign matter, to separate the foreign matter by vibrating the food waste passed through the belt transfer type magnetic separator (27).

Next, the food waste via the vibrating screen 36 is transferred to the compression molding machine 38 to undergo a compression molding to a predetermined size.

The compression molding machine 38 is a conventional device that compresses the material to a predetermined size, and the food waste conveyed from the vibrating screen 36 is supplied into the compression molding machine 38 to be compressed in size and shape for easy transportation. It is molded.

The food waste, which is dried as described above and finally compressed to a size that is easy to transport, is loaded on a transport vehicle and transported to a predetermined place.

Herein, the deodorizing process performed at the same time as the drying process of the food waste of the first and second screw dryers 10 and 12 and the rotary dryer 14 is performed will be described below.

As described above, the drying hot air supplied in the first and second screw dryers 10 and 12 and the rotary dryer 14 contains moisture after drying of the food waste. A discharge pipe line 66b through which dry hot air is discharged is connected to the condenser 72.

The dry hot air containing the moisture is discharged to the first heat exchanger 62, 10% is discharged to the condenser 72 as described above along the discharge pipe line (66b).

At this time, the condenser 72 including the cooling device is connected to the deodorizer 40, the dry hot air containing moisture supplied to the condenser 72 via the discharge pipe line 66b is a condenser 72 Condensation takes place.

At this time, the moisture condensed by the condensation of the dry hot air containing moisture as described above is discharged to the sewage treatment plant, and the remaining dry hot air, that is, the dry hot air accompanied by the odor, is sucked out of the deodorizer 40 and is discharged. .

On the other hand, the food waste drying treatment apparatus according to the present invention, since a large amount of heat and sewage, such as a large amount of leachate is generated, it is most preferable to install the incinerator and sewage treatment plant in the adjacent site, if the conditions do not meet the burner instead of the heat source It can be used instead of a heat source.

As described above, according to the food waste drying processing method and apparatus according to the present invention, the food waste is dried to the equilibrium moisture content stabilized, so that it is easy to transport and store the dry stabilized food waste, and to avoid direct landfilling of food waste. It can prevent pollution and at the same time extend the life of landfills, and can also be used as fuel for incinerators in terms of alternative energy, and can be used as auxiliary feed and compost due to the good quality of dried state, The use of incineration heat from incinerators has the advantage of low facility and maintenance costs.

Claims (20)

The food waste drying treatment method includes a step of feeding food waste stored in a bunker 42 of a predetermined size into an input hopper 18 using an overhead crane 44 and a bucket 46, and the input hopper 18. Crushing the food waste introduced into the crusher 20, and dehydrating the leachate of the crushed food waste in the dehydrator 22 and dispersing the dehydrated and compressed solid food waste in the disperser 24; And removing the metallic foreign matter in the dispersed food waste by the rotary drum type magnetic separator (26), and putting the food waste from which the foreign matter has been removed into the quantitative discharge hopper (28) for continuous quantitative discharge and at the same time discharging the quantitative discharge. A step of quantitatively transporting the food waste discharged in a quantitative manner from the hopper 28 to the preheater 16 via a quantitative supply feeder 30; Preheating the food waste transported into the preheater 16 with steam heat supplied by the steam heat supply means so as to have a critical moisture content, and passing the preheated food waste through the screw conveyor 32 to the first screw dryer 10. And drying the food waste with the steam heat and the drying hot air supplied by the steam heat supply means and the dry hot air supply means, and the food waste spilled from the first screw dryer 10 by a screw conveyor. After passing through the 32) into the second screw dryer 12, the step of drying again by the steam heat and drying hot air, and the food waste discharged from the second screw dryer 12 via the screw conveyor 32 After the transfer to the rotary dryer 14, the final drying with the steam heat and the drying hot air, and the rotary dryer 14 After passing through the screw conveyor 32 and the apron conveyor 34 to the belt conveying type magnetic separator 27, the process of removing the metallic foreign matters again, and the food waste from which the foreign matters were removed again To remove the foreign substances by vibrating by passing the gas through the screw conveyor 32 to the vibrating screen 36, and feeding the food waste discharged from the vibrating screen 36 into the compression molding machine 38 to have a predetermined size. And a step of carrying out compression molding to form a molded body, and carrying the food waste in a dry state compression-molded to the predetermined size to a predetermined place. The method of claim 1, wherein the odor of the food waste generated during the drying process of the food waste passing through the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 in sequence is removed. The screw dryer (10), the second screw dryer (12) and the rotary dryer (14) is a food waste drying treatment method characterized in that the deodorizer (40) is connected to the pipe line and the process of removing the odor is carried out at the same time. The food waste drying apparatus includes an input hopper 18 into which food waste is input, a grinder 20 consisting of two parallel rotary cutters each having a plurality of hooks protruding from the motor and a reduction gear, and a feeding part. Dehydrator 22 consisting of a screw portion and a discharge portion having a housing having a certain cross section and a feed screw for compressing / dehydrating and transporting the food waste, and an impeller braid rotatably therein to disperse the compressed and dehydrated solid food waste. Disperser 24 equipped with a rotary drum type magnetic separator 26 having a permanent magnet part and a drive motor to remove metallic foreign substances in the food waste, and a fixed-quantity discharge hopper built-in a quantitative rotary valve to discharge the food waste. (28) and two-stage up and down in the two-stage housing (54) of a predetermined size and a fixed-supply feeder (30) for feeding a fixed amount A pair of upper and lower stages in a three stage housing 57 of a predetermined size, and a preheater 16 for preheating food waste by a pair of parallel shaftless screws 50 installed therein and a drive motor and steam heat supply means connected to each other. A first screw dryer 10 having a parallel shaftless screw 50 installed therein, the drive motor and a steam heat supply means and a dry hot wind supply means for rotating and driving the shaftless screw 50 installed side by side; The rotary screw 14 of the drum type equipped with the 2nd screw dryer 12, the drive motor, the steam heat supply means, the dry hot air supply means, and the oil burner 68, and the food waste discharged from this rotary dryer 14 Belt transfer type magnetic separator (27) for removing metal foreign matter from garbage again, Vibrating screen (36) equipped with a vibrator on the bottom to separate foreign matter from dried food waste, and dry food waste Compression molding machine 38 for compression molding to a predetermined size, suction type is connected to remove the odor of food waste generated in the first screw dryer 10, the second screw dryer 12 and the rotary dryer 14 Food waste drying treatment apparatus characterized in that the deodorizer 40 is configured in order. 4. The angle of the preheater (16), the first screw dryer (10), the second screw dryer (12), the rotary dryer (14), the belt conveying magnetic separator (27), and the vibration screen (36). A food waste drying processing apparatus, characterized in that a screw conveyor (32) having a conveying screw installed therein is provided as a means for transporting food waste. 4. The food waste drying apparatus according to claim 3, wherein an apron conveyor (34) is provided between the screw conveyor (32) connected to the discharge part of the rotary dryer (14) and the belt transfer type magnetic separator (27). The steam heat supply means according to claim 3, wherein the preheater 16, the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 are simultaneously connected to the steam heat supply pipe line 56a. Is the incineration steam heat 64 of the incinerator 65, characterized in that the food waste drying treatment apparatus. The drying hot air supply means according to claim 3, wherein the drying hot air supply means simultaneously connected to the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 by a dry hot air supply pipe line 56b is preferably in turn. Food waste drying apparatus characterized in that the first blower (60) and the first heat exchanger (62), the second blower (61) and the second heat exchanger (63) to be connected. The method of claim 3 or 7, wherein the second heat exchanger (63) is supplied to the drying hot air supply pipe line (56b) of the first and second screw dryers (10), (12) and the rotary dryer (14). Food waste drying treatment apparatus, characterized in that connected at the same time. The incineration vapor stream 64 is connected to the second heat exchanger 63 so as to receive heat, and between the first blower 60 and the second blower 61 to discharge the used heat. The first heat exchanger 62 is connected to the incinerator 65 so that the heat used in the first heat exchanger 62 is discharged again. Food waste drying treatment unit. 4. The incineration vapor stream 64 of the incinerator 65 supplied to the preheater 16, the first screw dryer 10, the second screw dryer 12 and the rotary dryer 14 is again fed. Food waste drying processing apparatus, characterized in that the discharge pipe line (66a) is connected to the incinerator (65) is installed to exit to the incinerator (65). The method of claim 3, wherein the first screw dryer 10, the second screw dryer 12, and the rotary dryer 14 are heat exchanged by a first heat exchanger 62 and a second heat exchanger 63. After the dry hot air of the blower 60 and the second blower 61 is supplied and wet-aired, the first heat exchanger 62 and the deodorizer 40 are deodorized so as to escape to the first heat exchanger 62 and the deodorizer 40. Food waste drying apparatus characterized in that the discharge pipe line (66b) is connected to the machine 40 is mounted. According to claim 3 or 11, wherein the discharge pipe line (66a) 90% of the wet air is discharged to the first heat exchanger 62, 10% of the wet air to the deodorizer 40 so that Food waste drying treatment apparatus, characterized in that the bifurcation discharge pipe line (66b). 13. The method of claim 3 or 12, wherein the condenser 72 including a cooling device is installed between the deodorizer 40 and the discharge pipe line 66b, and the moisture of the condensed wet air is a sewage treatment plant, and the water is removed. The odorous air has been discharged to the deodorizer 40, the food waste drying apparatus. 4. The food waste drying apparatus of claim 3, wherein the hopper portions of the feeding hopper 18 and the pulverizer 20 are formed asymmetrically and have a wide cross section in order to prevent the formation of bridges during the feeding of the food waste. . 4. The food waste of claim 3, wherein the pressure screw installed in the cylindrical housing having a constant cross-sectional area of the dehydrator 22 and rotated by a drive motor is formed in a shape in which the cross-sectional area is gradually increased with respect to the traveling direction of the food waste. Drying processing unit. 4. The food waste drying apparatus according to claim 3, wherein the oil burner (68) mounted to the rotary dryer (14) can replace the incineration steam heat (64) of the incinerator. 4. The food waste drying apparatus according to claim 3, wherein a bunker (42) of a predetermined size in which food waste before being fed into said feed hopper (18) is inserted and stored is provided adjacent to said feed hopper (18). 18. The bucket 46 according to claim 3 or 17, as a means for feeding and transporting the food waste stored in the bunker 42 to the feeding hopper 18, wherein the bucket 46 is mounted on the bunker 42 so as to be transported. Food waste drying treatment apparatus, characterized in that the overhead crane 44 is installed. 4. The food waste drying apparatus according to claim 3, wherein a bio filter layer (70) for filtering odors of food waste is installed on the roof layer of the plant where the food waste drying apparatus is installed. 4. The food waste drying apparatus of claim 3, wherein a control system for each food apparatus is provided to control the food waste drying apparatus.