WO2022054974A1

WO2022054974A1 - Apparatus for producing fouling-inhibiting hydrophobic cornstalk fuel for power generation using superheated steam

Info

Publication number: WO2022054974A1
Application number: PCT/KR2020/012119
Authority: WO
Inventors: 최영찬; 김용구; 최종원; 송규섭; 이영주; 박주형; 노영훈
Original assignee: 한국에너지기술연구원
Priority date: 2020-09-08
Filing date: 2020-09-08
Publication date: 2022-03-17

Abstract

The present invention relates to a cornstalk thermal energy processing apparatus, and relates to a dehydration system using steam in which, in a kiln-type cornstalk dehydrating apparatus, steam is sprayed across the full cross-section of the kiln main body for fuel dehydration, and, correspondingly, lifting vanes are used to induce free falling of the fuel to be dehydrated.

Description

Hydrophobic cornstalk fuel manufacturing device for power generation with suppressed fouling using superheated steam

The present invention relates to an apparatus for producing cornstalk fuel that heat-treats cornstalks using steam, and more particularly, to dry fuel in a kiln-type cornstalk drying apparatus by spraying steam over the entire cross-section of the kiln body and corresponding Thus, it relates to a drying system using steam for dropping a fuel to be dried using a falling blade.

Disposal of food waste from households and restaurants, as well as cow manure, pig manure, and chicken manure from livestock farms is emerging as a social problem. This is because the discharge of waste such as food waste and livestock manure to the sea is prohibited, and the utilization of compost or fuel using waste such as food or livestock manure is low.

In order to solve this problem, various various means have been proposed, for example, a method for manufacturing a solid fuel using sewage sludge, food waste, and combustible waste has been disclosed.

The solid fuel manufacturing method using food waste and combustible waste includes drying sewage sludge to a moisture content of 10 to 20% or less and then pulverizing; Lignite 10% (weight ratio): The process of mixing with the coke 10% (weight ratio) additive, the process of pulverizing the combustible waste to a particle size of 30-50 mm, the dried sewage sludge, food waste mixed with additives, grinding The process of mixing the prepared combustible waste in the ratio of sewage sludge 30% (weight ratio): food waste 30% (weight ratio): combustible waste 40% (weight ratio), and drying the mixture so that the water content is 10% or less; It consists of a process of extruding and molding to a predetermined size by adding a supporting material to the mixture after mixing and drying.

According to this method, food waste and sewage sludge can be recycled and used by drying and mixing sewage sludge, food waste and combustible waste, mixing lignite and coke, and then extruding to a predetermined size.

However, the solid fuel manufacturing method using food waste according to the prior art has the following problems.

There was a problem in that it takes a lot of money to lower the water content of sewage sludge or food waste having a high water content. That is, there was a problem in that a lot of energy was used to dry the sewage sludge and food waste.

In addition, in the solid fuel using food waste and sewage sludge produced by the above method, food waste and sewage sludge did not generate sufficient calorific value as fuel. There was a problem in that the cost to increase it increased.

In general, coal-fired thermal power plants burn about 180 tons of coal per 500 MW, and supply about 37 tons of coal equivalent to one pulverizer to the boiler.

In a 500MW thermal power plant using coal, approximately 6 coal storages with a capacity of approximately 500ton are installed, of which 5 are supplied with normal coal, and the remaining 1 is a reserve that can be used for a certain period of time. It is operated as a coal storage.

Moreover, in thermal power plants that use coal as fuel, the standard thermal power design criteria for coal is designed to use low-moisture bituminous coal of 6,080Kcal/Kg, 10% or less. Some thermal power plants use imported coal, and some sub-bituminous coals have an average moisture content of 17% or more, which lowers the combustion efficiency of the boiler.

If the calorific value of the coal used with the standardized combustion limit of 5,400Kcal/Kg is low, the reduction in combustion efficiency and the increase in fuel consumption are expected. Moreover, when using lignite, which is a low-calorie coal with high moisture (moisture of 25% or more), the moisture content is higher than the design standard, so the transport system for transporting coal is not smooth. As a result, the combustion efficiency decreases, the heat distribution within the boiler drifts, and the boiler is operated in an abnormal state. However, in order to reduce fuel cost in thermal power plants, the proportion of use of lignite is gradually increasing to about 41-60%.

That is, in general, the steam drying apparatus sends high-pressure steam to a jacket or tube to indirectly heat the solid fuel indirectly.

The present invention is an improved invention of Korean Patent Publication No. 10-1860037 registered by the present applicant, and the conventional solid fuel such as coal is dried at a high temperature when hot air of a certain temperature or higher is used. is generated, fine powder is generated, and when the volatile matter and fine dust reach the ignition temperature, it ignites and burns inside.

That is, when using general heat-exchanged high-temperature dry air (oxygen concentration of 21%), drying proceeds quickly, but inflammable materials are ignited.

In order to prevent ignition of combustible materials, drying of combustible materials so far has been done using dry air at a very low temperature (60~80 degrees), or indirectly contact the surface with a steam tube to avoid direct contact with high-temperature hot air. and dried.

Drying by low-temperature air or indirect heat transfer takes a long time and the device becomes very large. It is an invention to improve the problem of consumption.

Accordingly, the present invention has been devised to solve the above problem, and an apparatus for producing cornstalk fuel that can efficiently heat-treat cornstalks by directly using the heat energy contained in the steam by directly injecting steam to the object to be dried using steam. Its purpose is to provide

In addition, an object of the present invention is to provide a drying device that does not cause ignition of combustible materials and allows drying in a quick time by contacting high-temperature heat.

Another object of the present invention is to provide a drying apparatus using a phenomenon in which a raw material in contact with vapor saturated circulating air is heated, and moisture contained in the raw material is vaporized and evaporated to dryness.

Another object of the present invention is to provide an apparatus in which the surface of cornstalks is modified from hydrophilicity to hydrophobicity by steam.

According to a feature of the present invention for achieving the above object, the present invention provides a grinding unit for pulverizing cornstalks, a storage unit for storing the pulverized cornstalks, and a primary supplying the cornstalks to the fuel input unit of the heat treatment unit. The cornstalk fuel manufacturing apparatus may include a feeder and a heat treatment unit for heat-treating the cornstalk to a predetermined primary temperature condition.

In addition, it may include a cooling unit that cools and heats the cornstalk that has passed through the heat treatment unit to a predetermined secondary temperature condition.

In addition, it may further include; a heat supply unit for supplying heat to the heat treatment unit.

In addition, a cooling heat supply unit for supplying cooling heat to the cooling unit; may further include.

According to another aspect of the present invention for achieving the above object, the present invention provides a main body into which the cornstalk is put, a steam heater that generates warm heat to change the introduced steam into steam, and discharges residual heat after the change; A steam injection unit installed on the cornstalk outlet side of the main body and spraying steam to the raw material, a heating tube installed outside the kiln main body and passing the residual heat through to heat the surface of the kiln main body, the solid The raw material may be a heat treatment unit using steam, characterized in that it is double heated by the steam injected from the inside of the kiln body and residual heat passing through the heating tube.

In addition, the steam injection unit may be installed at the end of the main body, and a plurality of steam nozzles may be formed in a circular cross-section.

In addition, the heat treatment unit includes a main body into which the cornstalk is put, a steam heater that generates heat to change the incoming steam into steam, and discharges residual heat after the change, and is installed on the cornstalk outlet side of the main body and applies the steam to the raw material. a steam spraying unit for spraying; a heating tube installed on the outside of the kiln body to pass the residual heat to heat the surface of the kiln body; It may be an apparatus for producing cornstalk fuel, characterized in that it uses steam, characterized in that it is double dried.

In addition, the steam injection unit, a steam supply unit having a plurality of steam passages coupled to the steam nozzles at one end; a steam injection plate formed by introducing the steam nozzle; It may include a main steam nozzle coupled to the steam passage and formed on the central axis of the steam injection plate.

In addition, a curved member 425 for guiding the steam to be sprayed in the central direction of the main body along the circumference of the end of the steam injection plate; may include.

In addition, a vortex forming member 426 formed between the curved member and the tip of the steam injection plate to induce a vortex flow to the injected heated steam; may include.

In addition, the heat treatment unit includes one or more impurity removing units for removing impurities contained in the steam discharged from the main body, and the steam generated during the heat treatment of the cornstalk among the steam flow passing through the impurity removing unit. It may further include a discharge unit for discharging the flow rate.

According to the cornstalk steam treatment apparatus according to the present invention, the maximum drying effect can be obtained with little energy.

In addition, through the present invention, it is possible to maintain a constant drying efficiency by forming a counter flow, a parallel flow, and a cross flow with the fuel injection part of the steam injection part.

In addition, the steam injection unit has the effect of being dried through direct contact between the object to be dried and the steam by injecting steam in the opposite direction of the fuel inlet.

In addition, it is characterized in that the insulating material is further installed on the outer peripheral surface of the kiln body and the outer peripheral surface of the heating tube, it is possible to prevent heat loss inside the kiln body and the heating tube.

In addition, it is possible to increase the drying effect of the raw material, characterized in that the lifting blade is further installed on the inner surface of the kiln body so that the raw material flows freely from the top of the kiln.

In addition, when the cornstalk is dried, the surface of the dried cornstalk becomes hydrophobic, thereby preventing moisture re-adsorption.

In addition, when the surface is modified to be hydrophobic, when water droplets are dropped on the surface, the contact angle between the surface and the water droplets may be 30° C. or more.

As described above, there is an effect of the cornstalk steam processing apparatus of the present invention.

1 is a unit flow diagram of a solid fuel superheated steam processing apparatus according to a preferred embodiment of the present invention.

2 is a detailed view of a solid fuel superheated steam processing apparatus according to a preferred embodiment of the present invention.

3 is a detailed view of a grinding unit, a classification unit, and a forming unit according to a preferred embodiment of the present invention.

4 is a cross-sectional view taken along line A-A of a heat treatment apparatus according to a preferred embodiment of the present invention.

5 is a B-B cross-sectional view of a heat treatment apparatus according to a preferred embodiment of the present invention.

6 is a C-C cross-sectional view of a heat treatment apparatus according to a preferred embodiment of the present invention.

7 is a bird's eye view of a solid fuel superheated steam processing apparatus according to a preferred embodiment of the present invention.

8 is an industrial analysis, elemental analysis, and high calorific value and low calorific value of low-grade coal before processing of low-grade coal, which is a solid fuel, according to a preferred embodiment of the present invention.

9 is an industrial analysis, elemental analysis, and high calorific value and low calorific value of hybrid coal after treatment of low-grade coal, which is a solid fuel, according to a preferred embodiment of the present invention.

10 is a unit flow diagram of a steam processing apparatus for cornstalks according to a preferred embodiment of the present invention.

The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. Based on the principle that there is, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

Therefore, since the embodiment described in this specification is only the most preferred embodiment of the present invention and does not represent all the technical spirit of the present invention, there are various equivalents and modifications that can be substituted for them at the time of the present application. It should be understood that

A cornstalk steam processing apparatus according to a preferred embodiment of the present invention includes a storage unit for storing cornstalks, a primary feeder for supplying the cornstalks to a cornstalk input unit of a heat treatment unit, and a temperature condition for the cornstalks to a predetermined primary temperature. It is an apparatus for producing cornstalk fuel including a heat treatment unit for heat treatment.

The main body is a rotary furnace in the form of a cylinder.

The raw material is put inside the main body. The cornstalk is not limited to the type of raw material as long as it has the characteristics of a cornstalk having a calorific value, such as stems, leaves, and corn whiskers, except for corn fruits used for food or industry.

The raw material is input from the left side of the main body, and after the raw material is dried inside the main body, it is discharged to the outside through an outlet installed on the right side of the main body.

The raw material is double dried by steam injected from the inside of the main body and residual heat passing through a heating tube to be described later. These raw materials are ignited by the fuel component during drying and carbonization, and as in the present invention, when heated using high-temperature steam, there is an advantage in that the ignition of the fuel can be prevented. That is, when drying cornstalks, high-temperature hot air has a risk of ignition, so high-temperature steam is used, and high-temperature steam is directly sprayed toward the raw material flowing inside the body.

In addition, the high-temperature steam may be under normal pressure or low pressure.

The predetermined primary temperature condition of the cornstalk means that the temperature of the cornstalk at the time of being supplied to the heat treatment unit is lower than the predetermined primary temperature. The predetermined primary temperature means the temperature of the cornstalk when discharged from the heat treatment unit. As for the predetermined primary temperature, the average temperature of the cornstalk may be 200 to 400°C, preferably 250 to 350°C, and more preferably, the average temperature may be 300°C. The average temperature value is not a precisely specified value, and may be close to the average temperature value according to the properties of the cornstalks to be supplied.

The predetermined secondary temperature condition of the cornstalk means that the temperature of the cornstalk at the time of being supplied to the cooling unit is higher than the predetermined secondary temperature. The predetermined secondary temperature means the temperature of the cornstalk when discharged from the cooling unit. As for the predetermined secondary temperature, the average temperature of the cornstalk may be 50 to 250°C, preferably 100 to 200°C, and more preferably, the average temperature may be 150°C. The average temperature value is not a precisely specified value, and may be close to the average temperature value according to the properties of the cornstalks to be supplied.

The main body is rotated clockwise or counterclockwise by the main body driving unit, and the raw material that rises on the inner wall of the main body falls vertically from the inside of the main body as the angle of repose collapses. It is preferable that the rotation direction of the main body is the same as the movement direction of the exhaust gas passing through the heating tube, which will be described later. In addition, such a body is preferably installed to be inclined. More precisely, the raw material inlet in the body is installed higher than the raw material outlet. Thus, as the raw material input from the raw material inlet is dried in the main body by the rotation of the main body, it is easily discharged to the raw material outlet.

Although it is appropriate that such a main body driving part is a directly connected reducer type, any main body driving part for rotating a cylindrical rotary furnace may be used.

Falling wings are further installed on the inner surface of the main body to facilitate the flow of the raw material. The falling blade has the advantage of smoothing the flow of the raw material injected into the interior of the main body.

A steam injection unit to be described later is installed inside the main body, and a heating tube to be described later is installed outside the main body.

A body heat insulating material is further installed on the outer circumferential surface of the body. Thus, there is an advantage in that the heat inside the body can be prevented from being emitted to the outside by the insulating material.

An impurity treatment unit, which will be described later, is further installed at the inlet of the main body to remove dust included in the steam flowing into the main body.

Combustion air exhausted after heat exchange is exhausted with a large amount of heat (energy) depending on the exhaust temperature. At this time, the exhausted combustion gas is supplied to the heating jacket surrounding the outer cylinder of the drying device to heat the outer cylinder of the dryer, and the raw material inside is indirectly heated by the continuous transmission of the heated outer cylinder of the dryer. This saves a lot of energy because the wasted energy is reused.

The cornstalk fuel manufacturing device has a lifting flight that puts the raw material inside, lifts it up according to the rotation of the dryer body, and then drops it at a certain position. The location will be different.

It is raised up according to the rotation of the fuselage and then falls from a certain position by the falling wings repeatedly, and it shows a shape similar to that of a waterfall, so this is called the cascade effect. The raw material is dropped from the top, the surface of each particle is exposed, and the exposed surface is heated in contact with drying air (heating steam) and dried.

The heating tube is installed outside the main body. More precisely, the heating tube is installed on the outer peripheral surface of the main body. The heating tube heats the surface of the main body by passing heat discharged from a heat supply unit to be described later.

This heat means residual heat after the change of steam in the heat supply unit, which will be described later. That is, since the surface of the body is heated again with residual heat after using the heat source for changing saturated steam to steam for high-temperature steam heating, there is an advantage in that energy efficiency can be increased by recycling the heat source (energy).

The heating tube includes a residual heat inlet through which heat is introduced and a residual heat outlet through which heat is discharged.

An insulating material is further installed on the outer peripheral surface of the heating tube. This insulating material is the same as the insulating material installed in the body. The warm heat supply unit generates heat, changes the introduced saturated steam to steam, and discharges residual heat after the change.

The residual heat is exhaust residual heat exhausted after converting the saturated steam into the steam. The heat supply unit includes a heater body, a coil installed on the heater body, and a heat burner installed under the heater body. The heater body has a rectangular parallelepiped shape, and is narrower from the top to the top. A heating burner is installed under the heater body. The burner applies heat to a coil to be described later. A coil is installed inside the heater body. Steam moves inside the coil, and the saturated steam is changed into steam by the heat generated by the burner. That is, the pressure increases as the saturated steam changes to steam inside the heated coil, which serves to lower the pressure again through pressure control.

In addition, while the pressure of the steam is kept constant, the low pressure steam is sprayed at a constant pressure through the steam nozzle, and comes into direct contact with the dry raw material. The temperature of such steam is preferably between 300°C and 500°C.

One side of the coil is connected to a steam injection unit to be described later by a pipe, and the other side of the coil is connected to an impurity removing unit to be described later by a pipe.

A relief device is further installed in the discharge unit. The relief device automatically discharges steam when the pressure in the body increases. More precisely, the amount of steam generated during the drying of the raw material in the body is increased to automatically discharge the steam when the internal pressure of the body increases to a certain pressure or more. The internal pressure may be atmospheric pressure. Preferably it may be 0.1 bar to 30 bar, more preferably 1 bar to 5 bar. If the pressure condition is out of the above conditions, drying efficiency may be lowered.

Saturated steam from which dust and scattering is removed moves to the steam passing through the body. A fan is further installed at the rear end of the impurity removal unit. The fan directs the dedusted saturated steam to the coil.

A residual heat discharging portion is formed at an upper end of the heater body. The discharge unit discharges residual heat after being used to change steam in the coil. The residual heat discharge unit is connected to the heating tube by a pipe. More precisely, the residual heat discharge part is connected to the inlet of the heating tube by the pipe.

The steam injection unit is installed at one end of the body. Preferably, it may be installed at the fuel outlet side of the main body, and may be installed to form at least one of a flow direction opposite to the direction of fuel movement, a parallel flow, and a cross flow.

The steam injection unit may include a plurality of nozzles, but even if the nozzle is not included, steam is discharged through the steam injection unit, so that heat treatment of the cornstalk may be possible.

In addition, the steam injection unit may be installed at the end of the kiln body, and a plurality of steam nozzles may be formed in a circular cross-section.

In addition, the steam injection unit, a steam supply unit having a plurality of steam passages coupled to one end of the steam nozzles, a steam injection plate formed by introducing the steam nozzles, and formed on the central axis of the steam injection plate by being coupled to the steam passages It may include a main steam nozzle. The pressure of such a nozzle is preferably 0.0005 bar or less. Thus, there is an advantage that it is possible to prevent the scattering of the raw material in the powder state.

The injection pressure of these nozzles is preferably between 100 mmH ₂ O and 500 mmH ₂ O. The reason is that high-pressure steam is directly injected into the inputted raw material, and small particles and dust generated at this time are scattered and discharged to an impurity removal unit to be described later.

Thus, it is possible to maintain a constant injection pressure of the steam injected from the nozzle. That is, in order to compensate for the pressure lowered by the nozzle, the pressure is made constant through the pressure control device.

The cooling unit may include a cooling body for cooling the solid fuel that has passed through the heat treatment unit, and a cooling tube for supplying cooling heat through the entire area of the cooling body. A cooling water spraying unit installed above the cooling tube to spray cooling water onto the cornstalk; may be formed. A cooling water outlet through which cooling water is discharged from the cooling pipe after supplying cooling heat to the cornstalk; may be formed. The cooling water may be recirculated to be recovered and supplied to the cooling/heat supply unit.

It may further include a heat supply unit for supplying heat to the heat treatment unit. The heat supply unit may generate heat to change the introduced steam into steam, and discharge residual heat after the change. The average temperature of the steam supplied to the main body may be 400 to 700 ℃, preferably 450 to 600 ℃, more preferably the average temperature may be 550 ℃. The average temperature value is not a precisely specified value, and may be close to the average temperature value according to the properties of the cornstalks to be supplied.

The cornstalk fuel manufacturing apparatus may further include a cooling heat supply unit for supplying cooling heat to the cooling unit.

A main body into which the cornstalk is put, a steam spraying part installed on the cornstalk outlet side of the main body and spraying the steam to the cornstalk, installed outside the main body and heating the surface of the kiln body by passing the residual heat through It may include a tube, and the solid raw material may be a heat treatment unit using counterflow steam, characterized in that it is double heated by the steam injected from the inside of the kiln body and residual heat passing through the heating tube.

It is self-evident that the amount of supplied steam per unit time by weight may be adjusted in proportion to the amount of supplied cornstalk per unit time by weight. The weight-based supply amount per unit time of the cornstalk is defined as Qmf, and the weight-based supply amount per unit time of the steam is defined as Qms. The average ratio of Qms/Qmf may be 4 to 10, preferably 5 to 8, and more preferably 6 to.

The residual heat may be high-temperature exhaust gas and/or steam. The high temperature exhaust gas may be supplied through a separate main body burner. The high-temperature exhaust gas may be supplied through a heat burner of the heat supply unit.

The steam injection unit may be installed at the end of the body, and a plurality of steam nozzles may be formed in a circular cross-section.

The heat treatment unit includes a main body into which the cornstalk is put; a steam injection unit installed on the cornstalk outlet side of the main body and spraying the steam to the cornstalk; a heating tube installed on the outside of the main body to heat the surface of the main body by passing the residual heat through; and double drying by the steam sprayed from the inside of the cornstalk and residual heat passing through the heating tube It may be an apparatus for producing cornstalk fuel, characterized in that it uses countercurrent steam, characterized in that it becomes

The steam injection unit may include a steam supply unit having a plurality of steam passages coupled to one end of the steam nozzle, a steam injection plate formed by introducing the steam nozzles, and a steam main nozzle formed on the central axis of the steam injection plate by being coupled to the steam passages. may include

It may include a curved steam member for guiding the steam to be sprayed in the central direction of the main body along the circumference of the end of the steam injection plate.

It may include a steam vortex molding member formed between the curved member and the tip of the steam injection plate to induce a vortex flow to the injected heated steam.

The heat treatment unit includes one or more impurity removal units for removing impurities contained in the steam discharged from the main body, and the steam flow rate generated during thermal treatment of the solid fuel among the steam flow rates passing through the impurity removal unit It may further include a discharge unit for discharging the amount. The impurity removal unit may include one or more cyclones. The impurity removal unit may include one or more bag filters. The impurity removal unit may include one or more of the cyclones and/or bag filters. A turbo fan for circulating the steam may be formed at a rear end of the impurity removal unit.

Insulating material may be formed on all of the steam and steam pipes connecting the units, the cooling water pipe, and the exhaust gas pipe. Such an insulating material may be absolutely necessary in order to keep the temperature conditions of the steam, cooling water, and exhaust gas constant for each unit during operation of the thermal energy processing device.

In addition, the impurity removal unit is installed at the inlet of the main body.

The impurity removal unit removes the dust contained in the steam flowing into the interior of the body.

More precisely, the dust contained in the steam and the dust contained in the steam contained in the raw material injected into the body is also removed.

It is preferable that such an impurity removal unit is two or more cyclones. Thus, there is an advantage in that it is possible to efficiently remove the dust contained in the steam and the dust contained in the steam contained in the raw material.

Spontaneous ignition is possible only in the presence of oxygen in the air, and in the absence of oxygen, it uses the principle that it does not ignite even at high temperatures. Combustible raw materials that are easily ignited can be dried at a very low temperature when drying using dry air, and it takes a long time to dry. It is dried using heated high-temperature steam to dilute the oxygen concentration so that high-temperature drying is possible. Steam supplies boiler steam during initial preheating. At this time, the oxygen concentration of the circulating air is measured, and steam is supplied until it is 5% or less, and preheated. When preheating is complete and the oxygen concentration is below 5%, combustible raw materials such as cornstalks are supplied. The moisture contained in the combustible raw material evaporates, and the vapor becomes saturated in the circulating air, and the oxygen concentration is maintained below 3%. That is, the raw material is dried and the discharged steam remains in the continuously circulating heated air and is converted into saturated steam.

If the heated steam temperature is maintained at 300 degrees or higher, heat transfer to the raw material is facilitated, and the moisture contained in the raw material is evaporated and included in the steam discharged through the steam outlet.

The steam generated during drying from the raw material is partially discharged to the outside through the discharge unit by measuring the internal pressure.

Such a cornstalk fuel manufacturing apparatus has the advantage of being able to increase energy efficiency by recycling energy in a closed cycle cycle.

When the circulating heating steam was used at 400~500℃, the surface temperature of the cornstalk, the dryness target, was heated to 250~300℃, and the surface of the cornstalk was modified to change from hydrophilicity to hydrophobicity. It is exposed to the atmosphere so that it does not absorb moisture again even when it comes into direct contact with moisture such as rain, so it is okay to store it outside.

Also, if the cornstalk is hydrophobic, spontaneous combustion in the atmosphere is prevented.

If raw materials are stored outside in summer before drying, the internal temperature rises to 69℃, and spontaneous ignition occurs at this time.

Products dried by high-temperature steam by this cornstalk fuel manufacturing device do not rise above 45℃ even when left under the same conditions, and spontaneous ignition does not occur.

Accordingly, it is a device for drying combustible materials that spontaneously ignite at high temperatures, such as cornstalks, biomass, food waste, sewage sludge and livestock manure, wood chips, and sawdust.

In addition, when the surface is modified to be hydrophobic, the contact angle between the surface and the water droplet when the water droplet is dropped on the surface may be 30° C. or more.

The warm heat generating unit heats the circulating steam using an indirect heat exchange tube for combustion air burned in a burner or the like. The heated steam transfers heat to the raw material, and a part is cooled. At this time, when the steam is cooled below the dew point, it is condensed and converted back to water. Therefore, the circulating steam must be maintained at a temperature above the dew point. Usually, the temperature of the recirculated steam after drying is maintained at 100°C or higher. Compared to the conventional discharge of air at 100°C to the outside, because steam of 100°C is reheated and circulated, less heating energy is used.

Hereinafter, the operation of the present embodiment having the above-described configuration will be described.

(1) Put raw materials into the body.

(2) The heat supply unit generates heat to change saturated steam into steam, and after the change, the residual heat is discharged from the warm heat supply unit and supplied to the main body through the residual heat inlet.

(3) The steam flowing into the steam injection unit is sprayed onto the falling raw material while covering the cross-sectional area of the body by the falling blades to dry the raw material, and is double dried by the residual heat moving the heating tube.

(4) The steam flowing into the steam injection unit and part of the steam generated during the drying of raw materials are moved to the impurity treatment unit to remove dust, etc.

(5) After removal of impurities, the steam moves again to the heat supply unit by a fan.

(6) The heat supply unit generates heat and repeats the above operation.

The cooling unit may be a rotary drum cooler. The cooling unit passes a high-temperature raw material through the inside of the rotating drum, and the raw material flowing inside rises up on the inner surface of the cooling body. At this time, when cooling water is sprayed to the outside of the rotating cooling body to cool the outer surface of the cooling body drum, the principle of cooling the product inside by heat transfer from the surface is used.

A jacket-shaped outer plate is formed on the surface of the cooling pipe where the cooling water is sprayed to prevent the cooling water from scattering or the steam vaporized by the temperature is discharged to the outside. Exhaust to the outside through the exhaust port and volleyball fan.

Cooling water is used by circulating after cooling through the cooling and heat supply unit.

In addition, it may further include a buffer for alleviating the impact applied to the device when the cornstalk falls.

In addition, it may be possible to utilize the heat of the steam discharged from the relief device to the primary feeder and the heat treatment unit.

As the steam mentioned in the above specification, any one or more of steam containing no moisture and steam containing a large amount of moisture may be used, for example, superheated steam, saturated steam, steam, static pressure steam, vacuum steam, Flash steam, medium pressure steam, reheat steam, etc. may be included.

In addition, the reheat steam may be steam formed by increasing only the temperature in a state in which the pressure is maintained at normal pressure.

In addition, the vapor may be in any one or more states of normal pressure, low pressure, and high temperature conditions.

In addition, the device can be utilized for solid fuel other than cornstalk, and the invention for an embodiment targeting solid fuel is as follows.

A solid fuel superheated steam processing apparatus according to a preferred embodiment of the present invention includes a pulverizing unit 100 for pulverizing solid fuel; a separation unit 200 for separating the solid fuel pulverized in the pulverizing unit according to a predetermined particle size condition; a storage unit 300 for storing the solid fuel; a primary feeder 400 for supplying the solid fuel to the solid fuel input unit 1511 of the heat treatment unit; a heat treatment unit 500 for heat-treating the solid fuel to a predetermined primary temperature condition; and a cooling unit 600 that cools and heats the solid fuel that has passed through the heat treatment unit to a predetermined secondary temperature condition.

The main body is a rotary furnace in the form of a cylinder.

The raw material is put inside the main body. The solid fuel is not limited to the type as long as it can be used as boiler fuel. The solid fuel is not limited to the type as long as it has characteristics of a solid fuel having a calorific value, such as coal, biomass, and combustible waste.

More precisely, as shown in FIG. 2 , the raw material is input from the left side of the main body, and after the raw material is dried inside the main body, it is discharged to the outside through an outlet installed on the right side of the main body.

The raw material is double dried by superheated steam injected from the inside of the body and residual heat passing through a heating tube to be described later. These raw materials are ignited by the fuel component during drying and carbonization, and as in the present invention, when heated using high-temperature steam, there is an advantage in that the ignition of the fuel can be prevented. That is, when solid fuel is dried, high-temperature hot air has a risk of ignition, so high-temperature steam is used, and high-temperature steam is directly injected at low pressure toward the raw material flowing inside the body.

The pulverizing unit may include a pulverizer 110 for pulverizing the supplied solid fuel feedstock. At the rear end of the grinder, a separation unit 200 for separating the solid fuel according to a predetermined average particle size condition; may be formed. The particle size condition is absolutely necessary in order to form a heat treatment condition by uniformly adjusting the average particle size of the solid fuel supplied to the thermal energy processing device. The average particle size may be 50 mm or less, preferably 35 mm or less, and more preferably 25 mm or less. The solid fuel pulverized to the average particle size or more may be re-supplied to the pulverizer. If the solid fuel is not classified according to the particle size conditions, it is difficult to obtain a uniform heat treatment effect. In general, solid fuel having an average particle size of 6 mm or less and solid fuel having an average particle size of 6 to 25 mm can be divided and supplied.

A predetermined particle size condition for separating the pulverized solid fuel may be an average particle diameter of the solid fuel of 2 to 30 mm. Preferably, it may be 6 to 25 mm. More preferably, 6 mm or less is defined as a molded fuel, and 6 to 25 mm is defined as an unshaped fuel. The average particle diameter value is not a precisely specified value, and may be close to the average particle diameter value according to the properties of the supplied solid fuel. Accordingly, the solid fuel can be separated into an unshaped fuel and a molded fuel based on an average particle diameter of 6 mm under the predetermined particle size condition. In addition, if the average particle diameter exceeds 25 mm, it is necessary to change the processing conditions of the re-grinding step or the grinding unit for additional grinding.

The predetermined primary temperature condition of the solid fuel means that the temperature of the solid fuel at the time of being supplied to the heat treatment unit is lower than the predetermined primary temperature. The predetermined primary temperature means the temperature of the solid fuel when discharged from the heat treatment unit. As for the predetermined primary temperature, the average temperature of the solid fuel may be 200 to 400 °C, preferably 250 to 350 °C, and more preferably, the average temperature may be 300 °C. The average temperature value is not a precisely specified value and may be close to the average temperature value according to the properties of the supplied solid fuel.

The predetermined secondary temperature condition of the solid fuel means that the temperature of the solid fuel at the time of being supplied to the cooling unit is higher than the predetermined secondary temperature. The predetermined secondary temperature means the temperature of the solid fuel when discharged from the cooling unit. As for the predetermined secondary temperature, the average temperature of the solid fuel may be 50 to 250 °C, preferably 100 to 200 °C, and more preferably, the average temperature may be 150 °C. The average temperature value is not a precisely specified value and may be close to the average temperature value according to the properties of the supplied solid fuel.

The main body, as shown in FIGS. 4 to 6, is rotated clockwise or counterclockwise by the main body driving unit, and the raw material that climbs up the inner wall of the main body falls vertically from the inside of the main body as the angle of repose collapses. . It is preferable that the rotation direction of the main body is the same as the movement direction of the exhaust gas passing through the heating tube, which will be described later. In addition, such a body is preferably installed to be inclined. More precisely, the raw material inlet in the body is installed higher than the raw material outlet. Thus, as the raw material input from the raw material inlet is dried in the main body by the rotation of the main body, it is easily discharged to the raw material outlet.

A superheated steam injection unit 1520 to be described later is installed inside the main body, and a heating tube 1530 to be described later is installed outside the main body 1510 .

A main body insulating material 1550 is further installed on the outer circumferential surface of the main body. Thus, there is an advantage in that the heat inside the body can be prevented from being emitted to the outside by the insulating material.

An impurity removal unit 1900, which will be described later, is further installed at the inlet of the body to remove dust included in the superheated steam flowing into the body.

The solid fuel thermal energy processing device has a lifting flight that puts the raw material inside, pulls it up according to the rotation of the dryer body, and then drops it at a certain position. The location will be different.

This heat means residual heat after the change of steam in the heat supply unit, which will be described later. That is, since the surface of the body is heated again with the residual heat after using the heat source for changing the saturated steam to the superheated steam for high-temperature steam heating, there is an advantage in that the energy efficiency can be increased by recycling the heat source (energy).

The heating tube includes a residual heat inlet 1531 through which heat is introduced and a residual heat outlet 1532 through which heat is discharged.

An insulating material is further installed on the outer peripheral surface of the heating tube. This insulating material is the same as the insulating material installed in the body. The warm heat supply unit generates heat, changes the introduced saturated steam to superheated steam, and discharges residual heat after the change.

The residual heat is exhaust residual heat exhausted after converting the saturated steam into the superheated steam. The heat supply unit includes a heater body, a coil installed on the heater body, and a heat burner installed under the heater body. The heater body has a rectangular parallelepiped shape, and is narrower from the top to the top. A heating burner is installed under the heater body. The burner applies heat to a coil to be described later. A coil is installed inside the heater body. Steam moves inside the coil, and the saturated steam is changed into superheated steam by the heat generated by the burner. That is, the pressure increases as the saturated steam changes into the superheated steam inside the heated coil, which lowers the pressure again through pressure control.

In addition, while the pressure of the superheated steam is kept constant, the superheated steam, which is low pressure, is sprayed at a constant pressure through the superheated steam nozzle 1521 so that it comes into direct contact with the dry raw material. The temperature of such superheated steam is preferably between 300°C and 500°C.

One side of the coil is connected to a superheated steam injection unit to be described later by a pipe, and the other side of the coil is connected to an impurity removing unit to be described later by a pipe.

A relief device is further installed in the discharge unit 2000 . The relief device automatically discharges the superheated steam when the pressure in the body increases. More precisely, the superheated steam is automatically discharged when the internal pressure of the main body increases to a predetermined pressure or more due to an increase in the amount of water vapor generated during the drying of the raw material in the main body. The internal pressure may be atmospheric pressure. Preferably it may be 0.1 bar to 30 bar, more preferably 1 bar to 5 bar. If the pressure condition is out of the above conditions, drying efficiency may be lowered.

The superheated steam injection unit is installed at one end of the main body. Preferably, it may be installed at the fuel outlet side of the main body, and may be installed to form a flow opposite to the movement direction of the fuel.

The superheated steam injection unit includes a plurality of nozzles.

The superheated steam injection unit may be installed at an end of the kiln body, and a plurality of superheated steam nozzles may be formed in a circular cross-section.

In addition, the superheated steam injection unit may include: a superheated steam supply unit having a plurality of superheated steam passages to which a superheated steam nozzle is coupled to one end thereof; a superheated steam injection plate formed by introducing the superheated steam nozzle; It may include a main superheated steam nozzle coupled to the superheated steam passage and formed on a central axis of the superheated steam injection plate. The pressure of such a nozzle is preferably 0.0005 bar or less. Thus, there is an advantage that it is possible to prevent the scattering of the raw material in the powder state.

The injection pressure of such a nozzle is preferably between 100mmH2O and 500mmH2O. The reason is that high-pressure steam is directly sprayed on the injected raw material, and small particles and dust generated at this time are scattered and discharged to an impurity removal unit to be described later.

Thus, it is possible to maintain a constant injection pressure of the superheated steam injected from the nozzle. That is, in order to compensate for the pressure lowered by the nozzle, the pressure is made constant through the pressure control device.

The cooling unit may include a cooling body 1610 in which the solid fuel that has passed through the heat treatment unit is cooled; It may include; a cooling pipe 1620 for supplying cooling heat through the entire area of the cooling body. A cooling water injection unit 1621 installed at the upper portion of the cooling pipe to inject cooling water to the solid fuel; may be formed. A cooling water outlet 1622 through which cooling water is discharged from the cooling pipe after supplying cooling heat to the solid fuel may be formed. The cooling water may be recirculated to be recovered and supplied to the cooling/heat supply unit.

It may further include; a heat supply unit 700 for supplying heat to the heat treatment unit. The heat supply unit may generate heat to change the introduced steam into superheated steam, and discharge residual heat after the change. The average temperature of the superheated steam supplied to the body may be 400 to 700 ℃, preferably 450 to 600 ℃, more preferably the average temperature may be 550 ℃. The average temperature value is not a precisely specified value and may be close to the average temperature value according to the properties of the supplied solid fuel.

Solid fuel thermal energy processing apparatus further comprising a; cooling heat supply unit 800 for supplying cooling heat to the cooling unit.

The main body 1510 into which the solid raw material is input; a solid raw material discharge port 1512 of the main body; a superheated steam injection unit 1520 installed on the side and spraying the superheated steam to the solid raw material; and a heating tube 530 installed on the outside of the main body and heating the surface of the kiln main body by passing the residual heat through; It may be a heat treatment unit using counterflow superheated steam, characterized in that it is double heated by residual heat.

It is obvious that the weight-based supply amount per unit time of the superheated steam supplied with respect to the weight-based supply amount per unit time of the supplied solid fuel can also be adjusted in proportion. The weight-based supply amount per unit time of the solid fuel is defined as Qmf, and the weight-based supply amount per unit time of the superheated steam is defined as Qms. The average ratio of Qms/Qmf may be 4 to 10, preferably 5 to 8, and more preferably 6 to.

The residual heat may be high-temperature exhaust gas and/or superheated steam. The high-temperature exhaust gas may be supplied through a separate body burner 1540. The high-temperature exhaust gas may be supplied through a heat burner 1710 of the heat supply unit.

The superheated steam spraying unit is installed at the end of the main body, and a plurality of superheated steam nozzles 1521 having a circular cross-section may be formed.

The heat treatment unit includes a main body into which a solid raw material is input; a superheated steam injection part installed on the solid raw material outlet side of the main body and spraying the superheated steam to the solid raw material; a heating tube installed on the outside of the main body and heating the surface of the main body by passing the residual heat through; It may be a solid fuel thermal energy processing device, characterized in that it uses counter-flow superheated steam, characterized in that it is dried.

The superheated steam injection unit may include: a superheated steam supply unit 1522 having a plurality of superheated steam passages coupled to one end of the superheated steam nozzle 1521; a superheated steam injection plate 1523 formed by introducing the superheated steam nozzle; The superheated steam main nozzle 1523 is coupled to the superheated steam passage and formed on the central axis of the superheated steam injection plate.

The superheated steam curved member 1525 for guiding the superheated steam to be sprayed in the central direction of the main body along the periphery of the end of the superheated steam spraying plate; may include.

The superheated steam vortex forming member 1526 is formed between the curved member and the end of the superheated steam spray plate to induce a vortex flow to the sprayed heated steam.

The heat treatment unit includes one or two or more impurity removal units 1900 for removing impurities contained in the steam discharged from the body, and during thermal treatment of the solid fuel in the steam flow rate that has passed through the impurity removal unit A discharge unit 2000 for discharging as much as the generated steam flow rate; may be additionally included. The impurity removal unit may include; one or more cyclones (910). The impurity removal unit may include one or more bag filters 1920 . The impurity removal unit may include one or more of the cyclones and/or bag filters. A turbo fan 1930 for circulating the steam may be formed at the rear end of the impurity removal unit.

The superheated steam and steam pipe connecting the respective units, the cooling water pipe, and the exhaust gas pipe may all be formed of an insulating material. Such an insulating material may be absolutely necessary in order to keep the temperature conditions of the superheated steam, cooling water, and exhaust gas constant for each unit during operation of the thermal energy processing device.

Among the heat-treated solid fuels, the average particle size may be 10 mm or less, preferably 8 mm or less, and more preferably 6 mm or less solid fuel may be briquetteed through the forming unit 2100;

The molding unit includes a screw feeder 2110, a briquette 2120 for supplying the solid fuel, a motor 2130 for supplying power to the screw feeder and the briquette, and a controller 2140 for controlling the molding conditions. can be composed of

The impurity removal unit is installed at the inlet of the main body.

The impurity removal unit removes the dust contained in the superheated steam flowing into the interior of the body.

More precisely, the dust contained in the superheated steam and the dust contained in the water vapor contained in the raw material injected into the body are also removed.

It is preferable that such an impurity removal unit is two or more cyclones (1910). Thus, there is an advantage in that it is possible to efficiently remove the dust contained in the superheated steam and the dust contained in the water vapor contained in the raw material.

Spontaneous ignition is possible only in the presence of oxygen in the air, and in the absence of oxygen, it uses the principle that it does not ignite even at high temperatures. Combustible raw materials that are easily ignited can be dried at a very low temperature when drying using dry air, and it takes a long time to dry. It is dried using heated high-temperature steam to dilute the oxygen concentration so that high-temperature drying is possible. Steam supplies boiler steam during initial preheating. At this time, the oxygen concentration of the circulating air is measured, and steam is supplied until it is 5% or less, and preheated. When preheating is completed and the oxygen concentration is less than 5%, combustible raw materials such as coal are supplied. The moisture contained in the combustible raw material evaporates, and the water vapor in the circulating air becomes saturated, and the oxygen concentration is maintained below 3%. That is, the raw material is dried and the discharged water vapor remains in the continuously circulating heated air and is converted into saturated water vapor.

If the heated steam temperature is maintained at 300 degrees or higher, heat transfer to the raw material is facilitated, and the moisture contained in the raw material evaporates and is included in the vapor discharged through the steam outlet.

The water vapor generated during drying from the raw material is partially discharged to the outside through the discharge unit by measuring the internal pressure.

Such a solid fuel thermal energy processing apparatus has the advantage of being able to increase energy efficiency by recycling energy in a closed cycle cycle.

When 400-500 degrees Celsius of circulating heating steam is used, the surface temperature of the drying coal is heated to 250-300 degrees Celsius, and the surface of the coal is reformed and converted from hydrophilicity to hydrophobicity. It is exposed so that it does not absorb moisture again even when it comes into direct contact with moisture such as rain, so it is okay to store it outside.

In addition, if the solid fuel has hydrophobicity, spontaneous combustion in the atmosphere is also prevented.

If raw materials are stored outside in summer before drying, the internal temperature rises to 69 degrees, and spontaneous ignition occurs at this time.

The product dried by high-temperature steam by this solid fuel thermal energy processing device does not rise above 45 degrees even when left under the same conditions, and spontaneous ignition does not occur.

Coal dried using this solid fuel thermal energy processing device can form hybrid coal (HCK) of Korea Institute of Energy Research.

Therefore, it is a device for drying combustible materials that spontaneously ignite at high temperatures, such as coal, wood chips, and sawdust.

The warm heat generating unit heats the steam circulated using an indirect heat exchange tube for combustion air burned in a burner or the like. The heated water vapor transfers heat to the raw material, and a part is cooled. At this time, when the water vapor is cooled below the dew point, it is condensed and converted back to water. Therefore, the circulating water vapor must be maintained at a temperature above the dew point. Usually, the temperature of the recirculated steam after drying is maintained at 100 degrees or more. Compared to the conventional exhausting of air at 100°C to the outside, because water vapor at 100°C is reheated and circulated, less heating energy is used.

(Example 1)

As a result of drying the coal with 20% surface moisture and 8% crystalline moisture as a result of drying using a solid fuel superheated steam treatment device, the surface moisture was dried up to 5%.

(Example 2)

A comparison of the results of heat and cold heat treatment of solid fuel, which is low-grade coal, using a superheated steam treatment device is shown in FIGS. 8 and 9 .

As the low-grade coal used in the experiment, Indonesia's Adaro coal and Kideco coal were used, and the industrial analysis, elemental analysis, and high calorific value and low calorific value of these fuels are shown in FIG.

The industrial analysis, elemental analysis, high calorific value and low calorific value after heat treatment of the low coal using the superheated steam heat treatment apparatus according to the following experimental method are shown in FIG. 9 .

(1) Put raw materials into the body.

(2) The hot heat supply unit generates heat to change saturated steam into superheated steam, and after the change, the residual heat is discharged from the warm heat supply unit and supplied to the main body through the residual heat inlet.

(3) The superheated steam flowing into the superheated steam spraying unit is sprayed onto the falling raw material while covering the cross-sectional area of the body by the falling blades to dry the raw material, and is double dried by the residual heat moving the heating tube.

(4) Part of the superheated steam flowing into the superheated steam spraying unit and the steam generated during drying of raw materials moves to the impurity treatment unit to remove dust, etc.

(5) After removal of impurities, the saturated steam is moved again to the heat supply unit by a fan.

(6) The heat supply unit generates heat and repeats the above operation.

9, it can be seen that the low-grade coal is modified to have the calorific properties of the high-grade coal through heat treatment using superheated steam. properties can be maintained. Therefore, if the reformed hybrid coal is applied as a fuel for power generation, it is judged that it is possible to reduce environmental loads such as PM/greenhouse gas in addition to the characteristics of using high-grade coal in existing power generation facilities.

The cooling unit may be a rotary drum cooler. The cooling unit passes a high-temperature raw material through the inside of the rotating drum, and the raw material flowing inside rises up on the inner surface of the cooling body. At this time, when the cooling water is sprayed to the outside of the rotating cooling body to cool the outer surface of the cooling body drum, the principle of cooling the product inside is used by heat transfer from the surface.

A jacket-shaped outer plate is formed on the surface of the cooling pipe where the cooling water is sprayed to prevent the cooling water from scattering or the water vapor vaporized by the temperature from being discharged to the outside. Exhaust to the outside through the exhaust port and volleyball fan.

Cooling water is used by circulating after cooling through the cooling heat supply unit.

The temperature conditions mentioned in the above specification are Celsius conditions (°C).

As described above, although exemplary embodiments of the present invention have been illustrated and described, various modifications and other embodiments may be made by those skilled in the art. All such modifications and other embodiments are intended to be contemplated and encompassed by the appended claims, without departing from the true spirit and scope of the present invention.

100: crushing unit

110: grinder

200: separation unit

300: storage unit

400: primary feeder

500: heat treatment unit

510: body

511: fuel input unit

512: corn cob outlet

520: steam injection unit

521: steam nozzle

522: steam supply port

523: steam injection plate

524: steam main nozzle

525: curved member

526: vortex forming member

600: cooling unit

700: heat supply unit.

800: cooling heat supply unit

1510: body

1511: solid fuel inlet

1512: solid fuel outlet

1520: superheated steam injection unit

1521: superheated steam nozzle

1522: superheated steam supply unit

1523: superheated steam injection plate

1524: superheated steam main nozzle

1525: superheated steam curved member

1526: superheated steam air current forming member

1530: heating tube

1531: residual heat inlet

1532: residual heat discharge unit

1540: body burner

1550: body insulation material

1560: Fall Wings

1570: main body driving unit

1580: superheated steam inlet

1590: steam outlet

1610: cooling body

1620: cooling tube

1621: coolant injection unit

1710: heat burner

1900: impurity removal unit

1910: Cyclone

1920: bag filter

1930: Turbofan

2000: exhaust unit

2100: forming unit

2110: screw feeder

2120: briquette

2130: motor

2140: control unit

The present invention relates to an apparatus for producing cornstalk fuel that heats cornstalks using steam.

Claims

a grinding unit 100 for grinding cornstalks;

a storage unit 200 for storing the pulverized cornstalk;

a primary feeder 300 for supplying the cornstalk to the fuel input unit 411 of the heat treatment unit;

a heat treatment unit 400 for heat-treating the cornstalk to a predetermined primary temperature condition; and

and a cooling unit (500) that cools and heats the cornstalk that has passed through the heat treatment unit to a predetermined secondary temperature condition.
The method according to claim 1,

Cornstalk thermal energy processing apparatus further comprising; a heat supply unit (600) for supplying heat to the heat treatment unit.
The method according to claim 1,

A cornstalk thermal energy processing apparatus further comprising a; a cooling heat supply unit 700 for supplying cooling heat to the cooling unit.
a main body 410 into which the corn stalk is inserted;

a cornstalk outlet 412 of the main body; a steam injection unit 420 installed on the side and spraying steam to the cornstalk;

A heating tube 430 installed on the outside of the main body and passing the residual heat to heat the surface of the kiln main body; includes;

The heat treatment unit using steam, characterized in that the cornstalk is double heated by the steam injected from the inside of the kiln body and residual heat passing through the heating tube.
The method according to claim 1,

The main body into which the cornstalk is put;

a cornstalk outlet of the main body; a steam injection unit installed on the side and spraying steam to the cornstalk;

It includes a; heating tube installed on the outside of the main body to pass the residual heat to heat the surface of the kiln body;

The heat treatment unit using steam, characterized in that the cornstalk is double dried by the steam sprayed from the inside of the kiln body and residual heat passing through the heating tube.
5. The method according to claim 4,

The steam injection unit is installed at the end of the body,

Heat treatment unit using steam, characterized in that a plurality of steam nozzles are formed in a circular cross section.
5. The method according to claim 4,

The steam injection unit, a steam nozzle 421 at one end; a steam supply unit 422 having a plurality of coupled steam passages;

a steam injection plate 423 formed by introducing the steam nozzle;

and a steam main nozzle (424) coupled to the steam passage and formed on the central axis of the steam injection plate.
5. The method according to claim 4,

The temperature of the steam injected from the steam injection unit is a heat treatment unit using the steam injected at 400 to 500 ℃.
5. The method of claim 4,

A heat treatment unit using steam, wherein the surface temperature of the cornstalk is heated to 250 to 350° C. by the sprayed steam and the surface is modified to be hydrophobic.
The method according to claim 1,

The heat treatment unit includes one or two or more impurity removal units for removing impurities contained in the steam discharged from the body;

The cornstalk thermal energy treatment apparatus further comprising a; a discharge unit for discharging as much as the steam flow rate generated during the heat treatment of the cornstalk among the steam flow rate passing through the impurity removal unit.
5. The method according to claim 4,

A heat treatment unit using steam whose surface is hydrophobically modified so that the contact angle between the cornstalk and the ground passing through the heat treatment unit is 30° or more.