JP4876465B2 - Biomass fuel supply system - Google Patents

Description

  The present invention mainly carbonizes woody biomass (hereinafter referred to as “woody biomass” as appropriate) represented by forestry-related waste wood (timber waste, thinned wood, firewood, etc.) and waste wood and construction waste wood. And a biomass fuel supply system formed by pulverization.

  Biomass energy has been recognized as new energy following the amendment of the “Special Measures Act on Promotion of New Energy Utilization” in 2002. In addition, the law required domestic electric utilities to use new energy in excess of the standard amount in the future.

  “Biomass”, recognized as a new energy, is a collective term for biological resources, such as agriculture (wheat straw, sugarcane, rice bran, vegetation, etc.), forestry (waste sawwood, thinned wood, wood firewood, etc.), livestock (livestock disposal) Products), fisheries (fishery processing residue, etc.), waste (food waste, construction waste, etc.). One of the legal purposes of the aforementioned law is to utilize these biomass as new energy for environmental protection.

  At present, many schemes have been attempted in order to search for an effective utilization method of biomass, and a method has already been proposed in which biomass is chipped and burned or gasified.

  In addition, as one of the biomass utilization methods mentioned above, there is an expectation for a method of co-firing woody biomass with coal and other fuels as a fuel in thermal power generation facilities, etc. ing.

In addition, when co-firing the above-mentioned woody biomass with coal in a coal-fired power generation facility, it is efficient to make fine powder having a predetermined particle size or less while carbonizing the woody biomass, for example, Patent Document 1 It is described in.
JP 2005-114261 A

  However, the method disclosed in Patent Document 1 described above requires energy for carbonizing the woody biomass, unlike the case where the woody biomass is directly injected into a boiler or the like as a fuel. The problem is whether it can be efficient.

  In general, woody biomass before carbonization is bulky, and therefore the amount that can be transported at one time by transport means such as a truck is limited, and transport efficiency is poor. For this reason, when woody biomass is directly brought into a power generation facility or the like, and carbonized and pulverized there to produce fuel, there is a problem in that transportation efficiency is low and power generation costs and the like remain high.

  The present invention has been made in view of this problem, and an object thereof is to provide a biomass fuel supply system having low efficiency and cost including transportation efficiency.

The biomass fuel supply system according to the present invention includes a carbonization furnace that is provided in a garbage incineration facility and carbonizes woody biomass to generate carbides, and a particle size that is provided in the garbage incineration facility and has a size suitable for combustion of the carbides. A crusher for crushing, a granulator for pelletizing the carbide crushed by the crusher provided in a garbage incineration facility, and crushing the carbide pelletized by the granulator provided in a power plant And a crusher for supplying to the boiler of the power plant.

  According to the present invention, biomass is carbonized by a carbonization furnace provided in many garbage incineration facilities installed throughout the country, and this carbide is pulverized by a pulverizer provided in the garbage incineration facility. Furthermore, if exhaust gas from a garbage incineration facility is used, energy for carbonization can be saved, which is preferable. In addition, the woody biomass before carbonization is bulky and has a problem that the amount that can be transported at one time is limited and the conveyance efficiency is poor. What is necessary is just to convey this to the incineration facility, and to convey the woody biomass by which the volume after carbonization and grinding | pulverization was made small from the garbage incineration facilities of various places to the power generation equipment. For this reason, transportation costs can be saved and an efficient biomass fuel supply system can be constructed.

  Next, a biomass fuel supply system according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a conceptual diagram showing an overall configuration of a biomass fuel supply system according to the present embodiment. One of the features of this biomass fuel supply system is that it is provided adjacent to a garbage incineration plant 100 installed in various places in Japan as shown in FIG. This biomass fuel supply system includes a primary crusher 10, a carbonization furnace 20, a cooling device 30, a preliminary pulverizer 40, a centrifuge 50, a vertical pulverizer 60, and a granulator 70.

The primary crusher 10 is for cutting wood biomass up to a size that can be charged into the carbonization furnace 20. The carbonization furnace 20 is for carbonizing the woody biomass pulverized by the primary crusher 10 using the exhaust gas discharged from the incinerator 110 of the garbage incineration plant 100. The cooling device 30 is for cooling the woody biomass after carbonization discharged from the carbonization furnace 20. The pre-pulverizer 40 is for pre-pulverizing (coarsing) the carbonized woody biomass cooled by the cooling device 30. The centrifugal separator 50 functions as a foreign matter removing device that removes foreign matters such as metals from the woody biomass preliminarily crushed by the preliminary pulverizer 40 by centrifugation. The vertical pulverizer 60 is for pulverizing the pre-ground material until it becomes a fine powder having a size suitable for combustion. The granulator 70 is for granulating the pulverized fuel into pellets. The biomass fuel that has been pelletized and discharged from the granulator 70 is conveyed to the power plant 200 by a truck or the like, crushed by the crusher 80, mixed with pulverized coal, and burned in the power generation boiler 90. Thus, the generated energy is obtained.

  As described above, in the biomass fuel supply system of the present embodiment, the woody biomass is carbonized in the carbonization furnace 20 using the waste heat of the garbage incineration plant 100 and is pulverized by the vertical crusher 60 or the like. It is pelletized to produce biomass fuel. Since the woody biomass before carbonization is bulky, the amount that can be transported at one time is limited, resulting in poor transport efficiency and high transport costs. By installing this system consisting of the carbonization furnace 20 and the like at garbage incinerators installed in various parts of the country, collection of woody biomass generated in each part becomes easy. And the operation | work for reducing the volume of the wood type biomass containing carbonization, grinding | pulverization, pelletization, etc. is performed in a place as close as possible to the generation | occurrence | production location of such biomass. Thereby, transportation cost can be reduced and it can contribute to the high efficiency of biomass power generation.

  A specific configuration example of the primary crusher 10 is shown in FIG. The primary crusher 10 includes a housing 11, an input port 12 provided on the upper portion, a mill 13, and a drive motor 14. The woody biomass charged from the charging port 12 is crushed by the mill 13 into a size that can be charged into the carbonization furnace 20, for example, about 30 cm square. This primary crusher 10 can also finely grind the woody biomass to the extent of coarse powder. However, even if metal foreign matters are finely pulverized to a coarse powder level, they remain in the woody biomass and are difficult to separate, and fine pulverization with foreign matters may cause damage to the primary crusher 10. is there. Therefore, it is preferable to stop the crushing to a size that can be charged into the carbonization furnace 20.

  As another example of the primary crusher 10, a so-called jaw crusher type primary crusher may be employed. The jaw crusher type is a form in which the crushed material is crushed between the fixed plate and the swing jaw by swinging the swing jaw (movable plate) supported at one end in the housing back and forth toward the fixed plate. is there. In addition, various types of primary crushers can be used as long as primary crushing to the extent that the carbonization furnace 20 can be charged is possible. In addition, when the waste wood etc. collected in the garbage incineration plant 100 are small enough to be put into the carbonization furnace 20 from the beginning, the primary crusher 10 can be omitted.

  A specific configuration example of the carbonization furnace 20 is shown in FIG. The carbonization furnace 20 is a double-layered rotary kiln type carbonization furnace, and includes an outer cylinder 21, an inner cylinder 22, and a charging port 23 formed of heat-resistant bricks. The woody biomass crushed by the primary crusher 10 is fed into the cylindrical passage 24 inside the inner cylinder 22 through the inlet 23. Air supply from the outside is restricted to the cylindrical passage 24. Further, exhaust gas from the incinerator 110 is introduced into the outer peripheral passage 25 formed between the outer cylinder 21 and the inner cylinder 22. The woody biomass introduced into the cylindrical passage 24 is carbonized by the heat of the exhaust gas, and then discharged from the outlet on the side opposite to the inlet 23. The dry distillation gas that has contributed to carbonization in the cylindrical passage 24 is circulated to the incinerator 110 in order to increase the combustion efficiency of the incinerator 110. Here, the rotary kiln type is illustrated as the carbonization furnace 20, but is not limited to this, for example, a closed-type charcoal kiln type, a trolley type, a stirring type, a continuous rotary type, a repetitive rocking type, or a screw type. Etc. Carbonization conditions used in the carbonization furnace 20 vary depending on the type of the carbonization furnace 20 and the type of woody biomass to be treated, but are generally carbonized in the range of about 400 ° C to 700 ° C. .

  The cooling device 30 cools the carbonized woody biomass taken out from the carbonization furnace 20 to, for example, 100 ° C. or less. The cooling temperature may be a temperature at which oxidation does not proceed even if it is put into the atmosphere and can be charged into the preliminary pulverizer 40. In addition, as a cooling method, for example, a water-cooled type can be employed, but is not limited thereto, and other known cooling devices can also be used.

  As the primary crusher 10, a jaw crusher type can be used as the preliminary crusher 40. By the preliminary pulverizer 40, the carbonized biomass fuel is pulverized to a coarse powder having a size of about 1 cm square, for example. Since it is carbonized, the foreign substances (metal etc.) contained in the woody biomass can be easily separated from the biomass even when pulverized to the extent of this coarse powder.

  The centrifuge 50 applies a centrifugal force to the biomass in such a state to separate foreign substances. In the case of a centrifuge, various foreign matters such as ceramics, cements, and earths other than metal foreign matters can be removed. In addition, it is possible to use other well-known foreign material separators, such as a magnet type metal foreign material separator, instead of the centrifuge. By removing the foreign matter in this way, damage to the next vertical crusher 60 is prevented. If the woody biomass after carbonization pulverized by the preliminary pulverizer 40 without removing foreign matter is put into the vertical pulverizer 60, the pulverizing roller and rotary table of the vertical pulverizer 60 are damaged, and in the worst case The process of removing foreign matter is important because there is a risk that sparks may be generated due to rubbing of metals, leading to a serious disaster such as a fire. However, if the woody biomass collected in the garbage incineration plant 100 is of a nature that does not contain such foreign matter, the centrifuge 50 can be omitted.

  Next, an example of the structure of the vertical crusher 60 will be described with reference to FIG. The vertical crusher 60 is a so-called inner partial type air sweep type equipped with a rotary separator having a classification function. The vertical crusher 60 is provided with a supply pipe 603 for introducing coarsely pulverized woody biomass fuel supplied from the centrifuge 50. The vertical crusher 60 includes a crushing table 604. The crushing table 604 is a table on which the raw material supplied from the supply pipe 603 is placed. On the upper surface 604A of the pulverizing table 604, two to four conical (conical) pulverizing rollers 605 for pressing and pulverizing the object to be pulverized are disposed. Further, the crushing table 604 is configured to be decelerated by a reduction gear 612 from a motor 611 and to be driven to rotate about a vertical axis.

  Further, a nozzle 606 is formed between the outer peripheral surface of the pulverizing table 604 and the lower inner peripheral surface of the casing 1B, and the nozzle 606 discharges the jet air upward in the casing 1B. This blown air generates a swirl flow in the grinding chamber as a space surrounded by the inner surface of the casing 1 and the upper surface of the grinding table 604. Due to this swirl flow, the object to be crushed discharged from the outer peripheral surface of the pulverizing table 604 is transported upward of the pulverizing chamber. The discharge port 608 is for discharging fine powder out of the objects to be crushed (coarse powder and fine powder) crushed by the pulverization roller 605 on the upper surface 604A of the pulverization table 604.

  Further, a dam ring 604B is formed on the outer peripheral surface of the crushing table 604 so that the raw material has a predetermined deposition thickness on the crushing table 604. The material to be crushed (primary pulverized material) is supplied to the substantially central surface of the upper surface 604A of the pulverizing table 604 via the supply pipe 603. When the crushing table 604 is rotated, the material to be crushed is crushed by being narrowed between the upper surface 604A of the crushing table 604 and the crushing roller 605. Then, the powder pulverized in this way gets over the dam ring 604B when it becomes a predetermined thickness or more, and is blown up while being swung upward by the air flow ejected from the nozzle 606 below the outer periphery of the pulverization table 604.

  The mixed flow containing the powder thus pulverized becomes a uniform flow and swirls inside the casing 1B. At this time, the coarse powder component having a relatively heavy weight falls downward and is returned to the crushing table 604 by the separator 607. On the other hand, the fine powder component is discharged from the discharge port 608 to the outside. The particle size of the discharged fine powder component can be controlled by adjusting the flow rate of the air flow from the nozzle 606, the pressing force of the crushing roller 605, the rotational speed of the rotary table 604, and the like.

  Note that the vertical crusher 60 is not limited to the above-described air-swept type inner partial type, and may employ a fixed type separator, for example, according to the required fuel particle size. Further, it may be an external circulation type vertical crusher that does not include a separator inside, or may be a tire type vertical crusher in which the shape of the crushing roller is a spherical shape.

An example of a specific configuration of the granulator 70 will be described with reference to FIG. The granulator 70 includes a housing 1 </ b> C, a charging port 71, a stirring screw 72, and a granulating roller 73. The pulverized biomass fuel input from the input port 71 is supplied to the granulation roller 73 while being stirred by the stirring screw 72. It should be noted that, when pelletizing, a strong molding aid or the like is not used, and it is preferable that re-pulverization is facilitated by adding an appropriate amount of water. The granulating roller 73 is rotated by a motor (not shown), and the interval is controlled by the hydraulic unit 74, whereby the pulverized biomass fuel is pelletized and output to the outside. By making pelletization, the storage property of the fuel is improved and the transportation operation can be made efficient. The pelletized fuel is transported toward the power plant 200 by a truck or the like, and then pulverized again by the crusher 80 to be used for power generation. The reason why the pulverizer 80 is pulverized again is because the combustion efficiency can be increased after pulverizing and pulverizing the pellet-like fuel as it is.

  Next, the process of supplying woody biomass by this biomass fuel supply system will be described. Woody biomass such as building waste and thinned wood is transported to the garbage incineration plant 100 by a transportation means such as a truck. While such woody biomass occurs throughout the country, there is a problem that transportation is difficult due to its large volume, but in the case of the system of this embodiment, it is transported to garbage incineration sites existing throughout the country, Such transportation is a short distance, and the burden and cost of transportation are greatly reduced.

  The woody biomass transported to the garbage incineration plant 100 is first crushed by the primary crusher 10 and crushed to a size that can be charged into the carbonization furnace 20. In the case where the building waste material or the like is previously set to a size that can be directly input to the carbonization furnace 20, the building waste material or the like can be directly input to the carbonization furnace 20 without using the primary crusher 10.

Subsequently, exhaust gas discharged from the incinerator 110 of the garbage incinerator 100 is introduced into the carbonization furnace 20 to carbonize the woody biomass in the carbonization furnace 20. Carbonization conditions vary depending on the type of woody biomass, but generally carbonize in a temperature range of about 400 ° C to 700 ° C. The woody biomass carbonized and discharged in the carbonization furnace 20 is cooled to about 100 ° C. or less at one end by the cooling device 30 and then charged into the preliminary pulverizer 40. In the preliminary pulverizer 40, the input woody biomass is pulverized to a coarse powder of about 1 cm square. At this time, since the woody biomass has been carbonized, it is brittle and easily collapsed. Therefore, the woody biomass can be easily crushed, and the metal foreign matter and the like fixed inside can be easily separated. By applying the woody biomass in this state to the centrifuge 50, metallic foreign matters and the like can be removed from the woody biomass. Thereby, the safe driving | operation of the vertical crusher 60 is securable. The woody biomass from which foreign substances have been removed is put into a vertical crusher 60 and finely pulverized to a particle size suitable for combustion as a woody biomass fuel. The finely pulverized woody biomass is pelletized by the granulator 70 and is transported to the power plant 200 by a transportation means such as a truck in the pelletized state. In the power plant 200, after pelletized fuel is crushed by the crusher 80, it is put into a power generation boiler 90 and used as power generation energy together with pulverized coal that is put into another. In the granulation by the granulator 70 , water is only added and no strong coagulant aid is used. For this reason, pellet fuel can be easily crushed .

  The pelletized biomass fuel is reduced in volume and volume by carbonization and pulverization and is easy to transport, contributing to improvement in transport efficiency. Moreover, the pelletization can reduce the possibility of dust explosion and the like, and can improve the storage and safety.

  As described above, according to the present embodiment, the woody biomass is carbonized and pulverized using the waste incineration facilities 100 provided in many places throughout the country, thereby saving energy during carbonization. It is possible to reduce the transportation distance of woody biomass before carbonization with poor transportation efficiency and improve transportation costs and the like. In the present embodiment, as a preferred mode for improving combustion efficiency, a vertical crusher 60 that can finely pulverize the raw material is used, and the pulverized product after being finely pulverized can be easily conveyed. The pulverized product was pelletized by the granulator 70. However, in the case where the carbonized woody biomass can be used as a fuel even if it is not finely pulverized, the process of the vertical pulverizer 60 and the granulator 70 is omitted, and the pulverized product is not finely pulverized. May be transported to the power plant 200 as fuel.

It is a key map showing the whole biomass fuel supply system composition concerning an embodiment of the invention. The specific structural example of the primary crusher 10 is shown. The specific structural example of the carbonization furnace 20 is shown. The specific structural example of the vertical crusher 60 is shown. The specific structural example of the granulator 70 is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Primary crusher, 11 ... Housing, 12 ... Loading port, 13 ... Mill, 14 ... Drive motor, 20 ... Carbonization furnace, 21 ... Outer cylinder, 22・ ・ ・ Inner cylinder, 23 ・ ・ ・ Input port, 24 ・ ・ ・ Cylinder passage, 25 ・ ・ ・ Outer peripheral passage, 30 ・ ・ ・ Cooling device, 40 ・ ・ ・ Preliminary pulverizer, 50 ・ ・ ・ Centrifuge, 60 ... vertical crusher, 70 ... granulator, 71 ... inlet, 72 ... stirring screw, 73 ... granulation roller, 74 ... hydraulic unit, 80・ Crusher, 90 ... boiler for power generation, 100 ... garbage incinerator, 110 ... incinerator, 200 ... power plant, 603 ... supply pipe, 604 ... grinding table, 605 ..Crushing roller, 606... Nozzle, 607... Separator, 608.・ ・ Motor, 612 ... Reducer.

Claims (4)

A carbonization furnace that is installed in a garbage incineration facility and carbonizes woody biomass to produce carbides;
A crusher provided in a garbage incineration facility for crushing the carbide to a particle size suitable for combustion ;
A granulator for pelletizing the carbide crushed by the crusher provided in a garbage incineration facility;
A biomass fuel supply system, comprising: a crusher provided in a power plant and configured to crush the carbide pelletized by the granulator and supply the carbide to the boiler of the power plant.   The biomass fuel supply system according to claim 1, wherein the carbonization furnace carbonizes the woody biomass using exhaust gas from the garbage incineration facility. The pulverizer includes a first pulverizer that pulverizes the carbide to coarse powder;
The biomass fuel supply system according to claim 1, further comprising a second pulverizer that pulverizes the coarse powder obtained by the preliminary pulverizer into fine powder.   The biomass fuel supply system according to claim 3, further comprising a foreign matter removing device for removing foreign matter from the coarse powder obtained by the first pulverizer.

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