JP2007254696A - Undiluted liquid for mixed fuel from wood biomass and fuel oil, and its use method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an undiluted liquid for mixed fuel of a wood biomass and a fuel oil and its utilizing method, for expanding the utilization of the wood biomass by reducing its transportation cost. <P>SOLUTION: The undiluted liquid for mixed fuel of wood biomass and fuel oil is prepared by mixing 30 to 50 wt.% of a pulverized and powdered wooden biomass into a fuel oil being a liquid component. This preparation is performed near to a place where the wooden biomass is generated, and the wooden biomass is transported to a thermal power plant or the like as a liquid. When in use, the mixed fuel undiluted liquid is diluted with a fuel oil to be used. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a mixed fuel stock solution of woody biomass and fuel oil and a method for using the same in order to effectively use woody biomass generated by logging of wood and the like, and to reduce its transportation cost.

  Biomass is a renewable organic resource derived from animals and plants. Typical examples include livestock excrement, food waste, waste paper, forest land residue, and sewage sludge. At present, there are attempts to actively use such biomass for the purpose of preventing global warming, forming a recycling-oriented society, and activating rural villages. The value is much lower than.

On the other hand, since April 1, 2003, the RPS (Renewable Portfolio Standard) law has been in effect. The RPS Law is a law aimed at promoting the spread of new energy, which obliges the country to use a certain amount or more of electricity obtained from new energy such as solar power generation and wind power. Therefore, electric power companies are considering co-firing coal and wood biomass to meet the standards of the RPS method.
For example, the following Patent Document 1 proposes a technique for efficiently burning coal and woody biomass.
JP-A-2005-291531

  Although several proposals have been made regarding the technology for using wood biomass at coal-fired power plants, the transportation cost has become the biggest bottleneck in expanding the use of wood biomass. In other words, the location where woody biomass is generated and the facilities for burning it are often separated, and considering the transportation costs, the use of woody biomass is not on a profitable basis, which is one reason that its use is discouraged. It was. Even in oil-fired power plants that use heavy crude oil as the main fuel, there is no movement to actively use woody biomass so far, despite the need to expand the range of biomass use in the industry. Was the actual situation.

  The present invention has been developed to solve such problems. That is, an object of the present invention is to provide a mixed fuel stock solution of woody biomass and fuel oil, and a method for using the same, in order to expand the use of woody biomass by reducing the transportation cost.

  In order to achieve the above-mentioned object, the present invention is prepared by mixing 30 to 50% by weight of wood biomass pulverized and pulverized with respect to a fuel oil that is a liquid component to generate thermal energy. Provided is a mixed fuel stock solution of woody biomass and fuel oil that is diluted with the fuel oil when used as a fuel for an internal combustion engine.

  Here, it is preferable that the particle size of the pulverized woody biomass is 50 to 1000 μm.

  Furthermore, the woody biomass can be carbonized before pulverizing the woody biomass.

  The internal combustion engine is a boiler (11), and heavy oil, light oil or crude oil is used as the fuel oil.

  Further, the present invention pulverizes and pulverizes woody biomass, mixes the pulverized woody biomass with fuel oil at a high concentration, and prepares a mixed fuel stock solution of woody biomass and fuel oil near the place where the woody biomass is generated. A mixed fuel stock solution preparation step (S101), a transport step (S102) for transporting the mixed fuel stock solution obtained in the mixed fuel stock solution preparation step to an internal combustion engine installation facility, and the mixed fuel stock solution in the internal combustion engine installation facility as the fuel A dilution step (S103) in which the concentration of the woody biomass diluted with oil is diluted to 1 to 10% by weight with respect to the fuel oil, and a combustion step (S104) in which the obtained diluted woody biomass-containing fuel is burned in the internal combustion engine. And a method for using a mixed fuel stock solution of woody biomass and fuel oil, characterized by comprising:

  Here, it is also preferable that the mixed fuel stock solution preparation step (S101) includes a step of carbonizing the woody biomass before pulverizing the woody biomass.

  In particular, the internal combustion engine is a boiler (11), and in the dilution step (S104), the mixed fuel stock solution of the woody biomass and the fuel oil is diluted with the fuel oil by about 2 to 3 times in the dilution tank (31). The diluted woody biomass-containing fuel thus obtained is further mixed in the auxiliary tank (33) for mixing with the fuel oil sent from the fuel oil storage tank (32) to dilute the woody biomass. It is preferable that after diluting to about 2 to 10 times the contained fuel, it is burned in an internal combustion engine.

  According to the present invention, a pulverized and pulverized woody biomass is mixed with fuel oil, which is a liquid component, at a high concentration near the biomass generation site to prepare a mixed fuel stock solution, and the fuel oil is contained in the woody biomass. By infiltrating, it ensures a certain fluidity and improves the handleability as a fuel, and by reducing the volume per unit calorific value, from the wood biomass generation point to the internal combustion engine installation facility far away The transportation cost can be reduced. In other words, by using woody biomass as a fluid, it becomes possible to pump using a pump, etc., making it easy to load into a tanker truck, etc., and reducing the volume also increases the amount to be loaded into a tanker truck, etc. be able to. Thereby, for example, it becomes possible to promote active use of woody biomass as a fuel for power generation in a thermal power plant.

  In addition, by carbonizing the woody biomass before it is pulverized, it is possible to remove some of the components that are not necessary for combustion in the woody biomass and to dry it, and to destroy the fiber structure of the woody biomass. Thus, the pulverization can be facilitated.

  When a mixed fuel stock solution of woody biomass and fuel oil is burned in an internal combustion engine, the mixed fuel stock solution is diluted with fuel oil at the installation facility of the internal combustion engine and used as a fuel with an appropriate concentration. can do. Further, the biomass fine particles impregnated with the fuel oil burn itself and become a core material for promoting the combustion of the fuel oil.

The invention aims to promote the use of wood biomass as a fuel, which has been previously disposed of as industrial waste, by reducing transportation costs, which was the biggest bottleneck in expanding the use of wood biomass. It is.
Hereinafter, the procedure for preparing woody biomass as a mixed fuel stock solution will be described first, and then this mixed fuel stock solution will be used as a fuel for boiler combustion in a thermal power plant as an example of an internal combustion engine for generating thermal energy. The case will be specifically described.

  Woody biomass is wood that has not been used effectively so far, such as timber, thinned wood, felled trees, pruned branches, sawdust, bark, chips, scraps, driftwood, grass, bamboo, firewood, wood construction waste, waste paper, etc. It is a concept that includes all materials.

  The woody biomass used in this example is assumed to be thinned wood or pruned branches generated in mountainous areas. FIG. 1 shows a flow chart of a procedure for preparing a mixed fuel stock solution of woody biomass and fuel oil of this example.

Woody biomass such as thinned wood is first accumulated in a gathering place such as firewood near the place of occurrence, and crushed into chips having a diameter of about 1 cm at that place. The crushed chips are allowed to stand and dry at the collection site until the contained moisture evaporates to some extent (for example, about half).
In addition, it is desirable to install a chipping device that pulverizes woody biomass into chips as close as possible to the location where the woody biomass is generated in order to shorten the transport distance of thinned wood before pulverization and reduce the labor involved in transportation. It is. Therefore, it is preferable to use a movable device that can be mounted on a vehicle as the chip-forming device.

The dried chips are loaded on a transport vehicle such as a truck and transported to the nearest grinding facility. In the pulverization facility, the chip is pulverized and pulverized to a particle size of 50 to 1000 μm using a known pulverizer. This particle size is a suitable size that can improve the combustion efficiency when woody biomass is mixed with fuel oil described later and burned.
The pulverized woody biomass is left to stand and dried until the water content is further reduced to about half. Of course, it is possible to forcibly dry the chips and the woody biomass using a dryer.

  The dried woody biomass fine powder is put into a mixing tank installed there in a pulverization facility, and is mixed and prepared with fuel oil, heavy oil, light oil or crude oil to form a mixed fuel stock solution. Since this mixed fuel stock solution is a tar-like liquid having a certain degree of fluidity, and can be pumped using a pump or the like, the handling property is improved. The woody biomass fines are mixed by 30 to 50% by weight with respect to the fuel oil which is a liquid component.

  The prepared mixed fuel stock solution of woody biomass and fuel oil is transferred to a tank truck or a freight train equipped with a tank through a pipe extending from the mixing tank by a pump, and is transported to an internal combustion engine installation facility.

  FIG. 2 shows a flow chart of another preparation procedure of the mixed fuel stock solution of the woody biomass and fuel oil of this example. As shown in the figure, this preparation procedure includes a step of carbonizing the woody biomass crushed into chips before the pulverization thereof.

The carbonization treatment of the chip is performed using a known carbonization apparatus that is generally commercially available. In addition to liquid fuel such as kerosene, dried chips or carbonized chips can be used as the fuel for the carbonization apparatus. Chip carbonization is preferably performed at an accumulation site near the generation site of the woody biomass in order to eliminate the trouble of transporting the chip, and therefore, it is preferable to use a movable device. Of course, it is possible to carry out the carbonization treatment in another place such as a grinding facility.
By carbonizing the chip before pulverization in this way, it is possible to remove the moisture content and components unnecessary for combustion to some extent, and further destroy the fiber structure of the woody biomass and facilitate its pulverization Can do.

The carbonized chips are transported to the nearest grinding facility in the same manner as described above, where they are pulverized to a particle size of 50 to 1000 μm by a grinding machine. The pulverized woody biomass is mixed by 30 to 50% by weight with respect to the fuel oil that is a liquid component, and is prepared as a mixed fuel stock solution of woody biomass and fuel oil.
In order to reduce transportation costs, if possible, pulverization of wood biomass into chips, pulverization of chips with a pulverizer, mixing of pulverized wood biomass and fuel oil, if possible, near the location where the wood biomass is generated. It is most preferable to carry out at one place such as a collecting place.

  The prepared mixed fuel mixture of woody biomass and fuel oil is transferred to a tanker truck or a freight train equipped with a tank through a pipe extending from the mixing tank by a pump in the same manner as described above, and transported to the installation facility of the internal combustion engine. Is done.

  In this way, near the place where the biomass is generated, pulverized and pulverized woody biomass is mixed with fuel oil, which is a liquid component, at a high concentration to prepare a mixed fuel stock solution, and the fuel oil is impregnated into the woody biomass (1) The volume per unit calorific value of very bulky woody biomass is reduced, (2) By ensuring a certain fluidity, it can be handled as a liquid fuel, and the handleability is improved (3 ) The effect of being able to avoid the influence of moisture etc. on the pulverized woody biomass is exhibited. This reduces the transportation cost and promotes the use of woody biomass as fuel.

  The schematic block diagram of the power plant of the thermal power plant which uses the mixed fuel stock solution of the woody biomass and fuel oil prepared for FIG. 3 as a fuel for boiler combustion was shown.

In this power plant 1, steam is generated by heating water in the superheater 12 by combustion of fuel in a boiler 11 that is an internal combustion engine for generating thermal energy, and the generated steam is passed through a turbine-related pipe 13. The turbine 14 is sent into the turbine casing to rotate at high speed around the shaft, and the rotation is transmitted to the generator 15 as power to generate power.
The power plant 1 includes a fuel system for supplying fuel to the boiler 11, a combustion system for burning fuel in the boiler, a condensate / steam system for generating steam from water and rotating the turbine 14, The system is roughly divided into four systems including a cooling system that supplies cooling water to the facilities of these systems.

  The fuel system for supplying fuel to the boiler 11 of the combustion system receives a fuel oil storage tank 32 for storing fuel oil that is heavy oil, light oil or crude oil, and a mixed fuel stock solution of woody biomass and fuel oil from a tank truck or the like. In addition, a dilution tank 31 connected by piping to the fuel oil storage tank 32 and an auxiliary mixing tank 33 connected by piping to the fuel oil storage tank 32 and the dilution tank 31 are provided.

  The boiler 11 of the combustion system has a furnace 11a for burning fuel as a main body. A combustion burner 11b is provided in the furnace 11a. Fuel is supplied to the combustion burner 11b from the auxiliary mixing tank 33, fuel is sprayed into the furnace from a burner nozzle (not shown), and combustion air is supplied from the forced air blower to burn the fuel in the furnace. Is done. An exhaust gas treatment facility 18 for treating the exhaust gas generated by the combustion is provided on the downstream side of the furnace 11a. In addition, this combustion system is not particularly different from the facilities of conventional thermal power plants that are generally operating.

Further, the condensate / steam system includes a condenser 19 that condenses the steam discharged from the turbine 14 into water, and the condenser is connected to the superheater 12 by a pipe 20. As a result, the condensate / steam system is a circulation system.
A cooling system (not shown) mainly cools the bearing lubricating oil of the turbine 14 and cools the exhaust steam discharged from the turbine 14 to the condenser 19.
The condensate / steam system and the cooling system are not particularly different from the existing thermal power plant facilities that are generally in operation.

In the fuel system of the thermal power plant described above, the mixed fuel stock solution of the woody biomass and the fuel oil of the present invention is subjected to dilution treatment as follows and then used as fuel for boilers.
The mixed fuel stock solution of woody biomass and fuel oil received by the dilution tank 31 from a tank lorry or the like is mixed in the dilution tank with the fuel oil introduced from the fuel oil storage tank 32 and diluted to about 2 to 3 times. Fluidity is improved. After that, it is sent to the mixing auxiliary tank 33 through the pipe, mixed with the fuel oil introduced from the fuel oil storage tank 32 in the mixing auxiliary tank 33, and further diluted to about 2 to 10 times. The concentration of the woody biomass in the prepared diluted woody biomass-containing fuel is about 1% by weight to 10% by weight which is optimal for combustion in the boiler.
If the dilution tank 31 is a large tank and the mixed fuel stock solution can be diluted to about 1 wt% to 10 wt% in the dilution tank, the auxiliary mixing tank 33 is not required. Can do.

The flow chart of FIG. 4 summarizes the utilization method of the mixed fuel stock solution of the present invention woody biomass and fuel oil in a thermal power plant.
This utilization method includes a mixed fuel stock solution preparation step (S101), a transport step (S102), a dilution step (S103), and a combustion step (S104).

In the mixed fuel stock solution preparing step, the wood biomass is pulverized and pulverized, and the pulverized wood biomass is mixed with fuel oil at a high concentration to prepare a mixed fuel stock solution of wood biomass and fuel oil. It is also preferable to carbonize the woody biomass before pulverizing.
The carbonization, pulverization, and mixing of the pulverized wood biomass and fuel oil are preferably performed near the location where the wood biomass is generated in order to reduce transportation costs, and more preferably performed at the same location.

  In the transportation process, the prepared mixed fuel stock solution is loaded into a transportation facility such as a tank truck and transported to a thermal power plant. In addition, since the mixed fuel stock solution obtained by mixing finely divided woody biomass with fuel oil has a certain fluidity and can be handled as a fluid, its handling property is improved. Moreover, since the calorific value per unit volume increases compared with the pulverized woody biomass, the transportation cost can also be reduced.

  In the dilution step, the mixed fuel stock solution is diluted with fuel oil to obtain an optimum concentration for burning the woody biomass in the boiler 11 of the thermal power plant. This concentration is about 1% to 10% by weight.

  In the combustion process, the obtained diluted woody biomass-containing fuel is burned in the boiler 11 of the thermal power plant. In addition, the particle size and concentration of the woody biomass fine powder in the diluted woody biomass-containing fuel are appropriately determined depending on the characteristics of the fuel injection nozzle provided in the boiler 11. The woody biomass-containing fuel oil is burned by an operation that does not change in the boiler and is used for power generation. By using the woody biomass-containing fuel oil, the woody biomass fine powder becomes a core material for promoting combustion, and it is possible to improve the combustion efficiency by reducing the unburned content, to suppress the combustion ash, and to suppress the NOx generation amount.

  The present invention is not limited to the embodiment of the invention described above, and promotes the use of woody biomass in an internal combustion engine installation facility such as a thermal power plant by reducing transportation costs and improving combustion efficiency. If there is, it is not limited to the structure as illustrated, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

  The present invention is intended to promote the use of woody biomass as a fuel for an internal combustion engine for generating thermal energy, and is not limited to an industrial internal combustion engine, but may be applied to a domestic internal combustion engine. Is possible. By promoting the use of woody biomass, it can effectively contribute to the prevention of global warming and the formation of a recycling society. The present invention can also be applied to raw materials that contain a carbon component and can be pulverized, such as plastics and cloth.

It is the flowchart which showed the preparation procedure of the mixed fuel stock solution of the woody biomass and fuel oil of a present Example. It is the flowchart which showed the other preparation procedure of the mixed fuel stock solution of the woody biomass and fuel oil of a present Example. It is the schematic block diagram which showed the power plant of the thermal power plant which utilizes the mixed fuel stock solution of the prepared woody biomass and fuel oil as a fuel for boiler combustion. It is the flow figure put together about the utilization method in the thermal power plant of the mixed fuel stock solution of the woody biomass and fuel oil of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power generation plant 11 Boiler 11a Furnace 11b Combustion burner 12 Superheater 13 Turbine connection piping 14 Turbine 15 Generator 18 Exhaust gas treatment equipment 19 Condenser 20 Piping 31 Dilution tank 32 Fuel oil storage tank 33 Auxiliary tank for mixing

Claims (7)

  Prepared by mixing 30 wt% to 50 wt% of woody biomass pulverized and pulverized with respect to fuel oil that is a liquid component, and the fuel oil when used as fuel for an internal combustion engine for generating thermal energy A mixed fuel stock solution of woody biomass and fuel oil, which is diluted with   2. The mixed fuel stock solution of woody biomass and fuel oil according to claim 1, wherein a particle size of the finely ground woody biomass is 50 to 1000 μm.   The mixed fuel stock solution of woody biomass and fuel oil according to claim 1, wherein the woody biomass is carbonized before pulverizing the woody biomass.   The mixed fuel stock solution of woody biomass and fuel oil according to claim 1, wherein the internal combustion engine is a boiler (11), and heavy oil, light oil or crude oil is used as the fuel oil. A mixed fuel stock solution preparation process that pulverizes and pulverizes woody biomass, mixes the pulverized woody biomass with fuel oil at a high concentration, and prepares a mixed fuel stock solution of woody biomass and fuel oil near the location where the woody biomass is generated (S101),
A transport step (S102) for transporting the mixed fuel stock solution obtained in the mixed fuel stock solution preparation step to an internal combustion engine installation facility;
A dilution step (S103) of diluting the mixed fuel stock solution with the fuel oil in an internal combustion engine installation facility and diluting the concentration of the woody biomass with respect to the fuel oil to 1 wt% to 10 wt%;
A method of using a mixed fuel stock solution of woody biomass and fuel oil, comprising a combustion step (S104) of burning the obtained diluted woody biomass-containing fuel in an internal combustion engine.   6. The mixed fuel of woody biomass and fuel oil according to claim 5, wherein the mixed fuel stock solution preparing step (S <b> 101) includes a step of carbonizing the woody biomass before pulverizing the woody biomass. How to use the stock solution. The internal combustion engine is a boiler (11);
In the dilution step (S104), fluidity is improved by diluting the mixed fuel stock solution of the woody biomass and fuel oil with the fuel oil in the dilution tank (31) by about 2 to 3 times, and the diluted wood obtained After the biomass-containing fuel is further mixed in the auxiliary tank for mixing (33) with the fuel oil sent from the fuel oil storage tank (32) and diluted to about 2 to 10 times the diluted woody biomass-containing fuel. The method of using a mixed fuel stock solution of woody biomass and fuel oil according to claim 5, which is burned by an internal combustion engine.

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