Solid Fuel Production System for Livestock Manure

Abstract

The present invention provides a system for converting livestock manure into solid fuel, comprising: a hopper (110) into which the transported livestock manure is fed; a dryer (140) that dries the livestock manure using a heat source supplied from a heat source supply device (200); a mixer (150) into which the dried livestock manure is fed and mixed with an excipient including sawdust or rice straw; and a pellet molding machine (160) into which the livestock manure is fed and molded into a pellet-shaped solid fuel, wherein the heat source supply device (200) comprises: a pyrolysis device (210) that pyrolyzes waste plastic; and a heat source supply device (220) that supplies a heat source to the dryer (140) using at least one of pyrolysis oil and synthetic gas generated by the pyrolysis.

Description

Technology Field

[0001] The present invention relates to the field of waste energy resource utilization technology, and more specifically, to a system technology for drying high-moisture livestock manure and manufacturing it into solid fuel by utilizing pyrolysis oil and byproduct gas generated from a waste plastic pyrolysis process as a heat source. Background Technology

[0002] Farms raising livestock such as cattle, pigs, and chickens generate livestock manure. In particular, large-scale livestock farms generate a massive amount of manure every day, and these farms spend considerable time and effort on processing the manure.

[0003] Livestock manure from farms generates complaints due to its foul odor and is also a cause of livestock diseases and environmental pollution. Consequently, there are concerns about the contraction of the livestock industry. Under these circumstances, the treatment of livestock manure is urgent, and the conversion of livestock manure into solid fuel is required to resolve these issues and utilize it as a raw material for power generation, driven by the expanded use of renewable energy.

[0004] Livestock manure, particularly cow manure, has a high moisture content, requiring a massive amount of energy for drying, and existing methods are highly dependent on fossil fuels, resulting in low economic feasibility. Meanwhile, the pyrolysis process for waste plastics generates pyrolysis oil, excess gas, and waste heat, but technologies to effectively integrate and utilize these resources in external processes have been limited. Prior art literature

[0005] Korean Registered Patent Publication No. 10-2645645 (Published July 7, 2023) The problem to be solved

[0006] The present invention aims to provide a system for converting livestock manure into solid fuel that can produce eco-friendly energy by converting livestock manure into solid fuel using pyrolysis oil and byproduct gas generated during the pyrolysis process of waste plastics, in order to solve the aforementioned problems. means of solving the problem

[0007] To solve the above problem, a solid fuel system for livestock manure according to one embodiment of the present invention comprises: a hopper (110) into which transported livestock manure is fed; a dryer (140) that dries the livestock manure using a heat source supplied from a heat source supply device (200); a mixer (150) into which the dried livestock manure is fed and mixed with an excipient including sawdust or rice straw; and a pellet molding machine (160) into which the livestock manure is fed and molded into a pellet-shaped solid fuel. The heat source supply device (200) may include a pyrolysis device (210) that pyrolyzes waste plastic; and a heat source supply device (220) that supplies a heat source to the dryer (140) using at least one of pyrolysis oil and synthetic gas generated by the pyrolysis.

[0008] Here, the dryer (140) is a screw-type dryer that dries the livestock manure while mixing it by stirring and conveying it with a screw conveyor, and the heat source is steam or heated heat medium oil generated by burning one or more of the pyrolysis oil and synthetic gas, and the livestock manure inside the dryer (140) can be indirectly heated using a circulation pipe of the steam or heat medium oil.

[0009] Additionally, the dryer (140) is a rotary kiln type dryer that dries the livestock manure by continuously moving it using an inclined rotating cylindrical drum, and the heat source is steam or heated heat medium oil generated by burning one or more of the pyrolysis oil and synthetic gas, and the livestock manure inside the dryer (140) may be indirectly heated through an inner or outer pipe through which the steam or heat medium oil flows.

[0010] Additionally, the dryer (140) is a rotary hot air dryer in which the livestock manure is dried by hot air introduced into a rotating cylindrical drum, and the hot air may be generated by heating by a steam heat source produced by burning one or more of the pyrolysis oil and synthetic gas.

[0011] Meanwhile, between the hopper (110) and the dryer (140), a crusher (120) for crushing livestock manure discharged from the hopper (110) may be further included.

[0012] Additionally, between the crusher (120) and the dryer (140), a fermenter (130) may be further included in which livestock manure discharged from the crusher (120) is fermented at high speed with air.

[0013] Additionally, the apparatus further includes a fermentation condenser (170) into which steam discharged from the fermenter (130) is introduced and condensed, and the condensate discharged from the fermentation condenser (170) in which the steam discharged from the fermenter (130) is condensed can be transferred to a wastewater treatment plant (190) for treatment.

[0014] Additionally, the apparatus further includes a drying condenser (180) into which steam discharged from the dryer (140) is introduced and condensed, and the condensate discharged from the drying condenser (180) in which the steam discharged from the dryer (140) is condensed can be transferred to the wastewater treatment plant (190) for treatment.

[0015] In addition, the screw-type dryer includes multiple screws, and the livestock manure is continuously dried through the multiple screws, and during the drying process, some of it is fed back to the inlet side of the dryer (140) to be mixed with the raw material and recycled.

[0016] In addition, the above livestock manure may include cow manure. Effects of the invention

[0017] The present invention, configured as described above, has the effect of providing a system for converting livestock manure into solid fuel that can produce eco-friendly energy by converting livestock manure into solid fuel using pyrolysis oil and byproduct gas generated during the pyrolysis process of waste plastics. Brief explanation of the drawing

[0018] FIG. 1 is an overall configuration diagram of a livestock manure solid fuel conversion system according to one embodiment of the present invention. FIG. 2 is a diagram showing the configuration of a screw-type dryer used in a livestock manure solid fuel conversion system according to one embodiment of the present invention. FIG. 3 is a diagram showing the configuration of a rotary hot air dryer used in a livestock manure solid fuel conversion system according to one embodiment of the present invention. Specific details for implementing the invention

[0019] The present invention relates to a system for drying high-moisture livestock manure and manufacturing it into solid fuel by utilizing pyrolysis oil and byproduct gas generated in a waste plastic pyrolysis process as heat sources, and will be described in detail below with reference to the drawings.

[0020] FIG. 1 is an overall configuration diagram of a livestock manure solid fuel conversion system according to one embodiment of the present invention, FIG. 2 is a configuration diagram of a screw-type dryer used in a livestock manure solid fuel conversion system according to one embodiment of the present invention, and FIG. 3 is a configuration diagram of a rotary hot air dryer used in a livestock manure solid fuel conversion system according to one embodiment of the present invention.

[0021] Referring to FIG. 1, a solid fuel system for livestock manure according to one embodiment of the present invention includes a hopper (110) into which transported livestock manure is fed, a dryer (140) for drying the livestock manure, a mixer (150) for mixing the livestock manure and an excipient, a pellet molding machine (160) for solid fueling, and a heat source supply device (200) for supplying a heat source to the dryer (140).

[0022] Livestock manure transported from a livestock farm is fed into the hopper (110). The hopper (110) is designed to smoothly supply manure that is highly viscous and mixed with foreign substances.

[0023] Since manure is highly adhesive and often causes a bridging phenomenon that clogs the discharge port, stirring blades and a vibrator are installed inside to prevent this.

[0024] A screw conveyor is connected to the bottom of the hopper (110) to discharge a certain amount of manure.

[0025] Since corrosive gases such as ammonia are generated from livestock manure, the hopper (110) is mainly made of stainless steel to improve durability.

[0026] The above dryer (140) dries the livestock manure using a heat source supplied from the heat source supply device (200). As the heat source, pyrolysis oil, synthetic gas, etc., generated through the pyrolysis of waste plastic are used.

[0027] Livestock manure dried in the above dryer (140) is fed into the above mixer (150) together with an excipient containing sawdust or rice straw and mixed.

[0028] The above mixer (150) is a device that uniformly mixes dried livestock manure with excipients such as rice husks and sawdust, and is commonly referred to as a continuous mixer or paddle mixer. Even if there is a large difference in specific gravity between the dried manure and the excipient, the paddle or ribbon blades mounted inside strongly agitate to produce a uniform consistency.

[0029] The above mixer (150) is precisely designed with a gap between the blade and the wall surface to account for the viscosity of the dry manure, and may include a reverse rotation function in case of overload.

[0030] The above livestock manure is fed into a pellet molding machine (160) and molded into solid fuel in the form of pellets.

[0031] The pellet molding machine (160), which is the final stage of livestock manure solid fuel conversion, is a device that applies strong pressure to the mixed raw materials to extrude them into a uniform rod shape (Pellet). The raw materials are passed between a die and a roller to increase density, and the frictional heat generated during this process activates the lignin components in the raw materials, allowing them to maintain a solid shape without the need for a separate adhesive. The pellet molding machine (160) may be made of a special alloy steel material to withstand wear caused by foreign substances such as sand in the manure.

[0032] The most stable pellets are produced when the moisture content of the raw materials, after drying and mixing, is around 15 to 20%, and since the pellets are hot and soft immediately after molding, they are then passed through a cooler and finally packaged.

[0033] The heat source supply device (200) that supplies a heat source to the dryer (140) comprises a pyrolysis unit (210) that pyrolyzes waste plastic, and a heat source supply unit (220) that supplies a heat source to the dryer (140) using at least one of pyrolysis oil and synthesis gas generated by the pyrolysis.

[0034] Pyrolysis refers to a technology that breaks the polymer chains of plastic by heating it to a high temperature of 300–550°C in an oxygen-free environment, converting it back into pyrolysis oil or gas. This enables chemical recycling, which turns plastic back into plastic raw materials.

[0035] Pyrolysis oil extracted through the pyrolysis process can be reused as a naphtha feedstock or utilized as fuel for power generation, and the carbon residue remaining after the pyrolysis reaction can be recycled into solid fuel, etc.

[0036] One of the key aspects of the present invention is to supply a heat source to the dryer (140) using at least one of the pyrolysis oil and synthesis gas generated by the pyrolysis. By using the renewable energy generated by the pyrolysis as a heat source for the dryer, it is possible to utilize it as an eco-friendly energy resource.

[0037] The above dryer (140) may be a screw-type dryer that dries the livestock manure while mixing it by stirring and conveying it with a screw conveyor. Screw-type dryers are mainly used for drying various forms of solid or high-viscosity materials such as sludge, waste, food, and chemicals.

[0038] Screw dryers evaporate moisture by transferring thermal energy while simultaneously stirring and transporting the material. As the screw (spiral blade) inside the dryer rotates, it continuously mixes (stirs) the material to be dried and transports it in one direction. This process prevents the formation of material clumps and increases drying efficiency. The heat source primarily utilizes an indirect heating method using heat transfer fluid or steam. The heat transfer fluid circulates within the double jacket of the dryer body or inside the screw shaft to transfer heat. The indirect heating method minimizes the leakage of dust, odors, and toxic gases generated during drying, and facilitates the recovery of solvents. Furthermore, it minimizes thermal denaturation of heat-sensitive materials and allows for the removal of only moisture.

[0039] When using a screw-type dryer, the heat source is steam or heated heat transfer fluid generated by burning one or more of the pyrolysis oil and synthetic gas, and the livestock manure inside the dryer (140) is heated indirectly using a circulation pipe of the steam or heat transfer fluid.

[0040] The above screw-type dryer includes multiple screws, and in the embodiment of FIG. 2, it is shown that it consists of two dryers, and each dryer includes eight screws.

[0041] The above livestock manure is continuously dried through the multiple screws, and during drying, some of it is fed back into the inlet of the dryer (140) to be mixed with the raw material and recycled. FIG. 2 illustrates an example in which livestock manure is continuously dried through eight screws, and 50% of the livestock manure that has passed through four screws is fed back into the inlet of the dryer. In this way, drying efficiency can be improved through recycling by feeding a portion of the livestock manure back into the inlet of the dryer during drying.

[0042] Additionally, the dryer (140) may be a rotary kiln type dryer that uses an inclined rotating cylindrical drum to continuously move and dry the livestock manure.

[0043] A rotary kiln dryer is equipment that performs high-temperature heat treatments, such as drying, firing, and sintering, by continuously moving materials using a slowly rotating and slightly inclined cylindrical drum. The rotary kiln automatically conveys and agitates materials and transfers heat by utilizing the rotation and inclination of the cylinder. In this invention, an indirect heating method is used in which the heat source is transferred through the outside of the cylinder or an internal tube, without direct contact with the material.

[0044] When using a rotary kiln type dryer, the heat source is steam or heated heat transfer fluid generated by burning one or more of the pyrolysis oil and synthetic gas, and the livestock manure inside the dryer (140) is indirectly heated through an inner and outer pipe through which the steam or heat transfer fluid flows.

[0045] Additionally, the dryer (140) may be a rotary hot air dryer in which the livestock manure is dried by hot air introduced into a rotating cylindrical drum.

[0046] A rotary hot air dryer combines the rotation of a cylindrical drum with hot air. Specialized for uniformly drying large quantities of materials, it is one of the most commonly used large dryers in industrial settings.

[0047] In a rotary hot air dryer, lifter blades inside the drum rotate to lift the material upward and drop it. During this process, the material scatters like a curtain, maximizing the contact area with the hot air. Since the material moves continuously from the inlet to the outlet along the incline of the drum, a large volume of raw material can be processed without interruption.

[0048] The above hot air is generated by heating it with a steam heat source produced by burning one or more of the above pyrolysis oil and synthesis gas.

[0049] Meanwhile, between the hopper (110) and the dryer (140), a crusher (120) for crushing livestock manure discharged from the hopper (110) may be further included. The crusher (120) is a device for breaking waste or materials into smaller pieces or chopping them finely.

[0050] Between the crusher (120) and the dryer (140), there may further include a fermenter (130) in which livestock manure discharged from the crusher (120) is fermented at high speed with air.

[0051] Through a high-temperature fermentation process, odor-causing components are decomposed and pathogens and parasite eggs in manure are killed, thereby improving the hygiene grade of the final product, solid fuel pellets.

[0052] The steam discharged from the above fermenter (130) is fed into the above fermentation condenser (170) and condensed into condensate and discharged, and the discharged condensate is transferred to a wastewater treatment plant (190) for treatment.

[0053] It may further include a drying condenser (180) into which steam discharged from the above dryer (140) is introduced and condensed.

[0054] The above drying condenser (180) converts the high-temperature, high-humidity steam discharged from the dryer (140) back into a liquid by bringing it into contact with a cold medium. In the livestock manure drying process, functions of odor control and heat recovery are performed beyond simple condensation.

[0055] The fine dust and odor-causing substances contained in the steam discharged from the above dryer (140) are dissolved in water, and only the uncondensed gas is sent to a separate deodorization facility, thereby increasing purification efficiency. In addition, the latent heat generated when the steam turns into water can be recovered and recycled as boiler feedwater or hot water for factory heating, thereby reducing energy costs.

[0056] The steam discharged from the above dryer (140) is condensed in the above drying condenser (180) and discharged as condensate, and is transferred to the above wastewater treatment plant (190) for treatment.

[0057] The above livestock manure may be cow manure, and also includes pig and chicken manure.

[0058] The foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications, changes, and substitutions within the scope of the essential characteristics of the present invention. Accordingly, these embodiments are intended to explain, not limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by these embodiments. The scope of protection of the present invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0059] 110: Hopper 120: Shredder 130: Fermenter 140: Dryer 150: Mixer 160: Pellet molding machine 170: Fermentation condenser 180: Dry condenser 190: Wastewater treatment plant 200: Heat source supply unit 210: Pyrolysis machine 220: Heat source supply

Claims

Claim 1 A hopper (110) into which the transported livestock manure is fed; a dryer (140) that dries the livestock manure using a heat source supplied from a heat source supply device (200); a mixer (150) into which the dried livestock manure is fed and mixed with an excipient including sawdust or rice straw; and a pellet molding machine (160) into which the livestock manure is fed and molded into a pellet-shaped solid fuel; wherein the heat source supply device (200) includes a pyrolysis machine (210) that pyrolyzes waste plastic; A system for converting livestock manure into solid fuel, comprising: a heat source supply unit (220) that supplies a heat source to a dryer (140) using at least one of the pyrolysis oil and synthetic gas generated by the pyrolysis above; wherein the dryer (140) is a screw-type dryer that dries the livestock manure while mixing it by stirring and conveying a screw conveyor; wherein the heat source is steam or heated heat medium oil generated by burning one or more of the pyrolysis oil and synthetic gas; wherein the livestock manure inside the dryer (140) is indirectly heated using a circulation pipe of the steam or heat medium oil; wherein the screw-type dryer includes a plurality of screws; wherein the livestock manure is continuously dried through the plurality of screws; and wherein, during the drying process, a portion is reintroduced to the inlet side of the dryer (140) to be mixed with the raw material and recycled. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 A system for converting livestock manure into solid fuel according to claim 1, further comprising a crusher (120) for crushing livestock manure discharged from the hopper (110) between the hopper (110) and the dryer (140). Claim 6 A system for converting livestock manure into solid fuel according to claim 5, further comprising a fermenter (130) between the crusher (120) and the dryer (140) in which livestock manure discharged from the crusher (120) is fermented at high speed with air. Claim 7 A system for converting livestock manure into solid fuel according to claim 6, further comprising a fermentation condenser (170) into which steam discharged from the fermenter (130) is introduced and condensed, and the condensate discharged from the fermentation condenser (170) in which the steam discharged from the fermenter (130) is condensed is transferred to a wastewater treatment plant (190) for treatment. Claim 8 A system for converting livestock manure into solid fuel according to claim 7, further comprising a drying condenser (180) into which steam discharged from the dryer (140) is introduced and condensed, and the condensate discharged from the drying condenser (180) in which the steam discharged from the dryer (140) is condensed is transferred to the wastewater treatment plant (190) for treatment. Claim 9 delete Claim 10 A system for converting livestock manure into solid fuel according to claim 1, wherein the livestock manure includes cow manure.

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