JP2012219130A - Method of utilizing woody biomass as energy source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently transport a woody biomass, to strengthen energy security in Japan and to strengthen a global warming countermeasure, by conducting economically effective use of the woody biomass as an energy source in Japan.SOLUTION: This method comprises: the first process for forming the woody biomass into wood chips having 10 cm or less of average diameter; the second process for heating a surface layer part of each wood chip from 250°C or more up to 450°C or less; the third process for crushing a bamboo to heat a surface layer part thereof from 250°C or more up to 450°C or less; the fourth process for mixing a material obtained in the second process with a material obtained in the third process, to be molded; and the fifth process for utilizing a transported material as the energy source. A ratio of adding the material treated by crushing the bamboo, in the fourth process, is brought into a range of 5-30% with respect to the whole. The process of using the material as the energy source in the fifth process is a process in a coal thermal electric power plant, or a pig iron-making process or steel-making process in an ironworks.

Description

  The present invention makes effective and efficient use of woody biomass (including bamboo) generated by logging required to keep the forest in a healthy state with a large carbon dioxide absorption capacity, and provides a self-sufficiency rate and zero emission power source in Japan. It relates to a method for increasing the ratio.

  In order to suppress the progress of global warming, it is an important issue to suppress the carbon dioxide hatching in the atmosphere. One of the most basic means to achieve this is to maintain the carbon dioxide absorption capacity of trees, bamboo and other plants by photosynthesis, to maximize the effective use of fixed organic matter, and to reduce the amount of fossil fuel used. It is possible to reduce. However, in Japan, during the transition period of energy sources to fossil fuels in the Showa 30s, trees shifted their focus to timber, and cedars and bushes planted in large quantities at that time reached the harvest season. However, the forestry industry has declined due to costly imports, and the carbon dioxide absorption capacity of the entire forest is declining. Most of the remaining forest land is not taken away, and various problems are caused by delays in thinning and neglect of natural forests. In addition, due to the lack of care of the forest, the overgrowth of bamboo forests has progressed, causing damage to trees.

On the other hand, in industries that use large amounts of energy, such as thermal power plants and steelworks, depending on fossil fuels such as coal and oil, it becomes difficult to respond to the movement of CO2 reduction. Therefore, the utilization of woody biomass is considered by taking advantage of the international privilege of carbon neutral, which is not counted as carbon dioxide even if burned. However, the following problems with woody biomass cannot be cleared, and concrete progress has been delayed.
(1) Since woody biomass is dispersed in place, contains a large amount of water, and has a low energy content per bulk, the transportation cost tends to be high and the amount collected in a large consumption area It has been considered difficult in terms of both costs.
(2) Also, in the energy mass consumption industries such as power plants and steelworks, even if it is not impossible in principle to use woody biomass as an energy source, current facilities and technologies can be used for fossil fuels. Since it has become suitable, it has been considered that it is difficult to use those that contain moisture or contain organic substances having a boiling point lower than that of coal, such as woody biomass. In other words, woody biomass is disadvantageous in terms of transportation and use compared to fossil fuels, and it is practical that various pretreatments to clear the problem impair the economy. This was the reason why the process did not progress.

  In Japan, based on the comprehensive biomass and Japan strategy established in 2002, we aim to realize a sustainable society “biomass and Japan” by utilizing biomass to the maximum extent possible. The development of the biomass town concept was promoted in about 300 municipalities nationwide. However, according to the policy evaluation of the Ministry of Internal Affairs and Communications administrative evaluation station announced in February 2011, the biomass-related business is (1) the plan published in the Biomass Town concept, and the ratio put into practice is low, (2 ) There are many things that have been put into practice and there are problems with the operation status. (3) Of those that are in operation, the ratio of income to expenditure is 50 to 80%, and it is not economically independent. (4) As a result, the result of the question of how much it contributes to Japan's energy security, global warming suppression, and regional development is shown, and the direction of the policy so far has been urged Yes.

Apart from this, in the national energy basic plan (established in June 2010), in order to strengthen comprehensive energy security and global warming countermeasures, which are important issues for Japan, (1) Energy self-sufficiency The ratio of domestic energy (renewable energy, etc.) and quasi-domestic energy (nuclear energy) out of the domestic primary energy supply is currently 38%
(2) The ratio of zero-emission power sources (derived from nuclear power and renewable energy) in the power source composition from the current 34%, more than 50% in 2020, and finally about 70% It is raised to raise. To that end, it was assumed that there would be a new nuclear installation (at least 14 units), a facility utilization rate increase (about 90%), and the maximum introduction of renewable energy.
However, due to the accident at the TEPCO Fukushima Daiichi Power Station accompanying the Great Tohoku / Kanto Earthquake on March 11, 2011, it is thought that it will be necessary to review the expansion of the use of nuclear power. In order to achieve (strengthening countermeasures against global warming), it will be necessary to re-challenge to increase “renewable energy”, especially to expand the use of biomass.

  In order to solve the problems as described above, (1) by appropriately logging based on the amount of tree growth, while maintaining the amount of carbon dioxide absorbed in the forest, (2) It is important to increase the ratio of renewable energy in Japan by effectively using trees and bamboo. The barrier that must be overcome is how to ensure economic efficiency. The idea for this is to promote comprehensive, integrated and effective as shown in the Biomass Utilization Promotion Basic Law (enforced in September 2009) and the Biomass Utilization Promotion Basic Plan (decided by the Cabinet in December 2010) ”,“ Maximum use according to the characteristics of each type of biomass ”. Considering the history of Japan's lack of international competitiveness in this field, specifically, (1) increasing productivity in work dealing with wood resources (mechanization, road network development), ( 2) In order to reduce the fixed cost burden, increase the operating rate (ie, increase the amount handled), (3) Furthermore, secure the demand for the large amount of wood resources obtained and respond to fluctuations in demand. It is necessary to create a system that can respond flexibly. Of these, (3) requires a technical response. In other words, in order to satisfy (3), there is no solution if we are concerned with local production for local consumption in the narrow sense of the past. Must be able to withstand medium and long-distance transportation.

  As a method for that, the timber lumber shown in Non-Patent Document 1 decomposes hemicellulose in the wood, is in an intermediate state between dry wood and charcoal, and holds 90% of the wood energy, Its production method is low-temperature pyrolysis using kiln, the product has no absorptivity and it is brittle with high density, and it can be used for boilers and fuels for small-scale power generation, metallurgical reducing agents, and gas raw materials. It is shown. Further, in Non-Patent Document 2, as a method for producing a toled biomass that replaces wood or charcoal, when a test of treating wood at 230 ° C., 250 ° C. and 280 ° C. for 1.2 to 3 hours is performed, As the processing temperature increases, the energy density increases, but the yield decreases. In addition, as a method of using woody biomass, in Patent Document 1, drying woody biomass at an ironworks, drying woody biomass using exhaust heat of 300 ° C. or less, pulverizing woody biomass after drying Using a coke molded body that is molded with coal to form a molded body, charged into a coke oven together with coal, and dry-distilled and used in a blast furnace, The method of blowing in is shown. In addition, in the Patent Document 2, the present inventors have a first step of converting a woody biomass into a piece of wood so that the average diameter is 1 cm or more and 10 cm or less in an accumulation area, and a surface layer portion of the wood piece is 350 ° C or more and 450 ° C or less. A method of using woody biomass in a method comprising a second step of heating so as to become, a third step of transferring to a place where a diameter of 1 cm or more is used, and a fourth step of crushing and using the transferred one Is shown.

JP 2008-24984 A

Bourgeois JP, Door J: Torrefied wood from temperature and tropical specialties, advertisements and prospects [Bioenergy, 153-159, 84, Vol. 3, ISBN; 0-85334-348-9] M.M. Pach, R.A. Zanzi, E .; Bjornbom (6th Asia-Pacific International Symposium on Combination and Energy} May. 2002. Kuala Lumpur, ISBN

  The present invention aims at strengthening Japan's energy security, strengthening global warming countermeasures, and promoting regional development by enabling the effective use of an appropriate amount of woody biomass in Japan. In particular, the present invention relates to a method for treating wood biomass in an accumulation area to enable economical medium-to-long distance transportation of wood biomass.

  The first means for solving the above problems is a first step of converting woody biomass into wood pieces so that the average diameter is 40 mm or less, and heating so that the surface layer portion of the wood pieces is 250 ° C. or higher and 450 ° C. or lower. 2nd step to perform, crush the bamboo and heat the surface layer part to 250 ° C. or higher and 450 ° C. or lower, mix the one obtained in the second step and the one obtained in the third step and mold It is a method comprising a fourth step and a fifth step in which the transported material is used as an energy source.

  The 2nd means is to make the ratio which adds what processed and crushed bamboo in the 4th process of 0007 into the range of 5 to 30% of the whole.

  The third of the means is that in the fifth step of 0007, the step of using as an energy source is mixed combustion in a coal-fired power plant.

  The fourth of the means is the fifth step of 0007, the step of using as an energy source is the ironmaking step of the steel mill, crushing the transported woody biomass and blowing it from the blast furnace or coal and It is mixed and molded and charged into a coke oven and charged into a blast furnace as a coke molded body.

  The fifth means is that the process used as an energy source in the fifth process of 0007 is a steelmaking process in an ironworks, and is pulverized to 1 mm or less into the high-temperature exhaust gas of the converter.

  According to the methods of 0007 and 0008, compression and molding can be efficiently performed to extend the transportable distance of the woody biomass, and processing such as drying can be made unnecessary at the use destination. By the method of 0009, the amount of carbon dioxide generation at a thermal power plant can be efficiently reduced. By the method 0010, it is possible to effectively reduce the amount of carbon dioxide generated in the ironmaking process of the steelworks. By the method of 0011, the sensible heat of the high-temperature exhaust gas in the steelmaking process of the steel works is effectively used to increase the calorific value of the converter exhaust gas, and the dust mainly composed of iron oxide contained in the exhaust gas is post-processed By making them easy to reuse, it is possible to reduce the amount of carbon dioxide generated at steelworks.

In the present invention, a concept for achieving both cost reduction and environmental conservation necessary for promoting the use of woody biomass as an energy source will be described. In this invention, the processing process in the accumulation place of the woody biomass and bamboo which were taken out from the forest is shown. Two cases of roasting method of woody biomass are shown. Of the process flow of the present invention, the processing process at the place of use of the medium / long distance transported to an ironworks or the like is shown.

FIG. 1 shows the concept of the present invention. The problem of Japanese forest policy after the 1950s is due to the failure to establish a system for economically using wood. For this reason, even if the planted trees enter the harvest season, timber is still imported. Imported wood is the majority of paper chips. In addition, energy applications are economically behind fossil fuel systems. As a result, forests are neglected and devastation is advancing, and as a countermeasure against global warming, which is a current issue, the carbon dioxide absorption capacity by photosynthesis is reduced. On the other hand, if forest trees are cut down too much, there is a risk that the devastation of other forests will proceed as seen after the end of World War II. Therefore, what is desired today is to “ensure the economics of using woody biomass while being aware of the environmental conservation of the forest”.
Many of the functions of forests include "water and soil conservation, biodiversity assurance, carbon dioxide absorption, production of wood, energy sources, etc., and provision of various contact areas with people as a satoyama forest". Yes. Since it is difficult to satisfy all of these with the same type of forest, it is necessary to perform zoning to environmental forests, living forests, production forests, etc., and to maintain them for each purpose. Environmental forests are left as natural as possible for the main purposes of water and soil conservation and biodiversity. Life forest emphasizes the elements of interaction with people. The subject of the present invention is a production forest, but partly includes a living forest. Here, it is necessary to be able to supply a variety of uses such as wood, paper chips, and various types of energy in a sustainable and economical manner with the quality and quantity required for each use. It is.
The first reason why Japanese wood was inferior to that of Europe and other countries is the low productivity from logging to primary processing. In order to improve it, it is necessary to promote the development of work roads and the mechanization of work, as already stated in the national policy. However, even if this is done, if the production scale of the business target is too small, the operation rate of the machine, etc. is low, the fixed cost burden is large, and the economic efficiency cannot be satisfied. In order to solve the problem, it is necessary to make the amount of wood handled by the business more than a certain scale (for example, tens of thousands of t / year or more). In contrast to this, in Japan, the target forest area is limited due to the jurisdiction of each forestry association and the administrative divisions found in the Baomas Town concept. Was not. Since there is a limit to the amount of tree growth in production forests, the area that will be considered for the wood utilization system should be expanded to include the adjacent areas as necessary. This eliminates the problem between maintaining the sustainability of production forests and the necessary forest size to ensure economic efficiency.
Next, we need to be able to maintain a flexible balance between supply and demand for wood. For that purpose, it is important to be able to use them in a comprehensive, multi-use, and cascade manner according to various woody tree types and parts having various characteristics. As in the past, a single-purpose project such as wood could not secure international competitiveness. On the other hand, it is not easy to secure economic efficiency, as seen in many examples of biomass use, in businesses that are limited to energy applications that do not add value. Uses for woody materials such as timber (having strict requirements for shape, etc.), paper-making chips (needed to contain no bark, etc.), livestock litter, composting materials, etc. The added value is small), and it can be used as various energy sources. While satisfying various requirements in terms of quality, and further satisfying each demand amount and its ratio as a whole, it is possible to increase the overall processing amount, thereby improving economy and enhancing competitiveness. It is a point of interest.

  The technology required to make it possible is a primary processing method that makes woody biomass economically capable of transporting over long distances. In other words, the use of wood as an energy source has so far included local stoves, boiler firewood, chips, pellets, etc., but these alone can be used for energy in terms of quality in the total amount of woody biomass. You can't consume something suitable. On the other hand, in order to economically carry out medium- and long-distance transportation, it is necessary to overcome weaknesses such as a large amount of water and low bulk specific gravity, which are problems in transportation of woody biomass. . Apart from this, it is desirable to make effective use of the prosperous bamboo, which has become a problem in the conservation of the current forest, and to develop the forest and to demonstrate its characteristics as a material. However, since the demand was too small, it was not fully utilized effectively.

FIG. 2 shows a process for treating woody biomass and bamboo taken from a forest in an accumulation area in the present invention. Applications of trees that have been cut in the forest include those used for wood, those used as paper chips, woody biomass, materials (such as livestock litter and compost production), and energy. Bamboo can be used for materials (craft, livestock feed, bamboo charcoal, etc.) and energy. In the conventional method, only timber was taken out from the logging site, and many others were left in the forest. In order to improve this, in the present invention, all the felled trees are transported to the accumulation place, where they are divided into purposes and necessary primary processing is performed for effective use.
As shown in FIG. 2, the wood treatment for wood and papermaking chips is the same as that of the conventional method, except for the portion of the tree used for wood and papermaking chips, for example, the bark portion, etc. It becomes a part for the energy that is the target of the target. The main energy woody biomass is thinned wood, etc., but in the present invention, these are crushed so that the average diameter is 40 mm or less and then subjected to heat treatment called roasting. At this time, other than the parts used for wood and papermaking chips can be used together. Roasting is also called trefaction, and in the case of woody biomass treatment, it means an intermediate heating temperature between drying (200 ° C. or less) and carbonization (450 ° C. or more). When this roasting treatment is performed on woody biomass with low thermal conductivity, conditions such as processing conditions (wood piece size) heating temperature, holding time, etc. vary greatly depending on how the homogeneity is considered. In order to obtain a relatively homogeneous intermediate product, the size of the piece of wood to be treated is reduced, the heating temperature is set to a relatively low temperature within the range of 200 to 350 ° C., and after the roasting treatment, pulverized and mixed. Then, the method of pelletizing it is taken. The method of the present invention is different. That is, in the present invention, as will be described later, since this intermediate product is pulverized at the place of use and separated or homogenized according to use, the difference in the content of hemicelluloses inside and outside is not a problem. Therefore, the present invention focuses on performing this process at a lower processing cost as long as the condition for efficiently transporting the intermediate product is satisfied.

  An example of the heating method is shown in FIG. The heating device includes a preheating part and a roasting part. Case 1 is a case where the roasted portion is heated by a direct heating method. The wood piece becomes an intermediate product through the preheating part and the roasting part, but from the exit side of the roasting part, a combustion burner is inserted, and the amount of woody biomass powder supplied to the burner is adjusted, Adjust to the heating temperature of the piece of wood described above. In addition, the decomposition product of hemicelluloses gasified by heating is burned by the air supplied from the burner and is used for heating the wood pieces. The high-temperature gas exiting the roasting section enters the preheating section, is used for preheating and drying the wood pieces, is subjected to exhaust gas treatment, and is discharged outside the system. The case 2 of FIG. 2 differs from the case 1 only in that the roasting portion is an indirect heating method. The hemicellulose produced from the wood pieces in the roasted portion is decomposed and gasified, and is sucked from the roasted portion and used as fuel for heating the roasted portion from the outside. The high-temperature gas generated by the combustion is heated from the outside to the roasting portion, and then introduced into the preheating portion. The baked wood pieces obtained in Case 1 or Case 2 are sieved with an average diameter of 1 cm or less.

  In the present invention, the processing described in 0017 is also performed for bamboo, and thereafter, it is pulverized together with a wooden processed material and molded. The blending ratio of bamboo is 5 to 30% of the whole. The roasting treatment may be performed from the beginning by combining the raw materials of wood and bamboo. The reason why 5% or more of bamboo is mixed is to increase the strength of the molded product when the powdery product is compressed and molded. On the other hand, the reason why the blending ratio of bamboo is set to 30% or less is to prevent bridging and other troubles in the powder conveying process and the like when pulverized in the fifth process and used as a powder. The wood and bamboo raw materials that have been roasted and mixed and pulverized are compression molded using a molding roll or the like. The average diameter of the molded product is suitably 10 to 50 mm.

  The molded product obtained by the method 0018 is transported by an appropriate means such as a truck, a railroad, or a ship according to the positional relationship between the accumulation place and the use place. FIG. 3 shows the processing after being transported to a place where a large amount of energy is used, such as a thermal power plant or a steel plant. In the case of a thermal power plant, the conveyed material is pulverized and mixed with pulverized coal in a thermal boiler for power generation. Compared to the use of wood biomass chips that have not been roasted, the features of those that have undergone roasting are low in water content and effective because they are hydrophobized after their water content has been reduced. It has a high calorific value, is more easily pulverized, and has less trouble on conveyors, hoppers, etc. than ordinary chips.

  One of the places where the woody biomass of the present invention is used is an ironworks. The conventional method of mass-production ironmaking using iron ore as a raw material is to first add iron ore sintered or formed into briquettes in a blast furnace (blast furnace) and coke obtained from coal, and then add air as an oxidizer. To produce a hot metal containing 4% or more of carbon. This is the iron making process. Next, in the steelmaking process, pure oxygen gas is blown onto this hot metal in a converter to oxidize the carbon content in the iron, and as a molten steel with a carbon concentration of 0.4% or less, adjustment of components such as alloy addition is performed. Then solidify to make a slab. After that, the steel product is made by performing molding processing, heat treatment, etc. necessary for the solid state. The present invention is directed to a steelmaking process using a blast furnace and a steelmaking process using a converter.

  The first method of using woody biomass in the iron making process is to blow the powdered powder together with air from the tuyere of the blast furnace to cause high temperature combustion. In the case of pulverized coal, the reason why it has not been done for woody biomass is that the blast furnace is made by lowering the flame temperature of the tuyere because it contains moisture and hemicellulose. This is because it adversely affects the progress of the reaction in the furnace. On the other hand, in this invention, what carried out the primary grinding | pulverization of the conveyed woody biomass can be sieved, and a 3 mm or less part can be blown in in a blast furnace through a tuyere. The second method of using wood biomass in the iron making process is to pulverize the transported wood biomass, mix it with coal, mold it, charge it into a coke oven, and charge it into a blast furnace as a coke molding. That is. At this time, the mixing ratio of the wooden molded product is set to a range that does not adversely affect the strength of the obtained molded coke, that is, 18% or less of the coal weight. In addition, you may grind | pulverize together with coal. The produced molded coke is charged from the upper part of the blast furnace together with the iron oxide raw material and the culture medium solvent to produce pig iron and molten slag.

The purpose of use in the steelmaking process is to link the sensible heat of the flue gas from the converter steelmaking furnace to the increase in the calorific value of the flue gas to increase the thermal efficiency of the entire steelworks, and the generated dust is mainly iron oxide. This is to make it easy to use as an iron source in a later process.
Hot metal is charged into a steelmaking converter and pure oxygen gas is blown through a lance. The carbon content in the molten carbon-containing iron thereby reacts with oxygen gas,
2C + O2 = 2CO (1)
The decarburization reaction proceeds as a result of this reaction. At this time, the temperature of the generated gas is as high as 1400 ° C. or higher, and the components are about 75% of carbon monoxide, about 13% of carbon dioxide, and trace amounts of oxygen, hydrogen, and nitrogen. In addition, the main component is iron oxide produced by oxidation of iron evaporated from the high-temperature part of molten iron in a high-temperature gas. In addition, metal components such as zinc contained in the hot metal are evaporated and oxidized. Is included. The high-temperature exhaust gas containing dust is cooled, the solid content is removed by a wet or dry dust collector, recovered as fuel gas, and used as an energy source in other processes of iron making. Moreover, the dust (dust) collected by the dust collector is reused as part of the iron source. In the conventional method, the sensible heat of the high temperature exhaust gas is not effectively effective. In addition, since the collected dust is only oxides, it is necessary to add a carbon source for reduction in the reuse.

  On the other hand, in the present invention, the granular material of the woody biomass is supplied into the high temperature gas of the steelmaking converter, the pyrolysis of the woody biomass is performed using the sensible heat of the high temperature gas, carbon monoxide, While producing | generating gas, such as hydrogen, the quantity of the fuel gas collect | recovered is increased and the calorific value is raised by reduce | restoring the carbon dioxide contained in high temperature gas, and converting into carbon monoxide. Of the added woody biomass, the carbon that has not been gasified is recovered together with dust, and the entire dust is collected and formed as necessary, and then used in subsequent processes for effective reduction of iron oxides. To do. At that time, it is necessary not to inhibit stable operation of the converter steelmaking process.

  In the present invention, the woody biomass conveyed to the steel mill is pulverized. In the present invention, what is carbonized by heating and remains as a solid is also collected together with dust and effectively used in the subsequent process. Therefore, the upper limit of the size of the wood biomass powder to be blown in is not strictly limited, but 3 mm per side. The following is desirable. As the gas for transporting the granular material, it is desirable to use a part of the gas recovered as the exhaust gas of the steelmaking converter. In addition, air, nitrogen gas, and the like can be used. However, in this case, a nitrogen content is mixed into the generated gas, which adversely affects the amount of heat generation, which is not preferable. About the position which blows the granular material of a woody biomass in the high temperature exhaust gas of a steelmaking converter, the inside of the steelmaking converter or the inside of the exhaust gas duct provided in the upper part of the steelmaking converter is possible. Hydrogen gas is generated when woody biomass is blown into the high-temperature exhaust gas. When the blowing position is in a steelmaking converter, the hydrogen-containing gas may come into contact with air that may enter from between the upper part of the converter and the lower part of the duct. In the worst case, it may cause a gas explosion. Can be. In order to avoid the risk, it is desirable that the wood biomass granular material is blown in the converter exhaust gas duct, not in the steelmaking converter. Furthermore, in order to avoid the risk of explosion due to the mixing of gas with hydrogen and entrained air, the woody biomass is supplied only when the steelmaking converter is in a steady state. desirable. For that purpose, the timing of blowing the woody biomass powder is set to be 3 minutes after the start of converter blowing and 2 minutes before the end of converter blowing.

  The high-temperature exhaust gas from the steelmaking converter into which the woody biomass granular material has been blown by the method 0024 is cooled and then separated into fuel gas and dust and collected by the dust collector. In the wet method, water cooling and slow dust are performed simultaneously. In the dry method, after the exhaust gas temperature is lowered to 500 ° C. or less by indirect cooling, dust is removed by an electric dust collector or a bag filter. The collected gas is once stored in a tank and supplied to a place where energy is required to be used as energy. On the other hand, as for the collected dust, what is obtained by this invention is accompanied by the solid carbon content resulting from woody biomass. Without separating the part containing iron and other oxides and carbon, if necessary, further adding solid carbon and forming it into pellets and briquettes as the amount necessary for oxide reduction. It is sent to another heating device for iron reduction recovery and processed, and finally effectively used as iron.

  In addition, wood and bamboo that have been roasted, or that have been molded after roasting, or defective products at the time of molding must be used in various energy conversion devices (boilers, gasification power generation, etc.) in the region. it can. By making it possible to meet the demand (including economic efficiency) of large-scale thermal power plants and steelworks as energy sources, it is possible to effectively use all the wood (including bamboo) brought out of the forest. It becomes possible.

  The accumulated trees were crushed so as to have an average diameter of 5 mm or more and 40 mm or less by the method of case 1 in FIG. The preheating part is a vertical type and the roasting part is a kiln type. The charging speed of the raw woody biomass (moisture content of 45 to 55%) is 15 t / h. The burner burns wood biomass powder (20 kg / min) as a heating source, and the maximum surface temperature of the wood pieces in the roasted portion was 380 to 440 ° C. The residence time in the roasting part is 25 minutes. The weight of the discharged treated wood piece was 45% at the time of charging. About the surface layer part 2mm of the wood piece after a process, the water | moisture content was 3% and the decomposition rate of hemicellulose was 98%. As the average composition of the wood pieces, when the average diameter was 30 mm, the water content was 5%, and the decomposition rate of hemicellulose was 48%. When the average diameter was 7 mm, the water content was 4% and the decomposition rate of hemicellulose was 85%.

  The accumulated trees were crushed so as to have an average diameter of not less than 5 mm and not more than 40 mm, and roasted by the method of case 2 in FIG. The preheating part is a vertical type and the roasting part is a kiln type. The charging speed of the raw woody biomass (moisture content of 45 to 55%) is 15 t / h. The heating source was a burner that was generated in the roasted portion and burned the hemicellulose decomposition gas, and the maximum surface temperature of the wood pieces in the roasted portion was 390 to 440 ° C. The residence time in the roasting part is 35 minutes. The weight of the discharged treated wood pieces was 48% at the time of charging. About the surface layer part 2mm of the wood piece after a process, the water | moisture content was 3% and the decomposition rate of hemicellulose was 98%. As the average composition of the wood pieces, when the average diameter was 30 mm, the water content was 5%, and the decomposition rate of hemicellulose was 48%. When the average diameter was 7 mm, the water content was 4% and the decomposition rate of hemicellulose was 85%.

  Bamboo was crushed to a length of 5 mm or more and 40 mm or less and roasted by the method of case 1 in FIG. The preheating part is a vertical type and the roasting part is a kiln type. The charging speed of the raw material bamboo (water content 45-55%) is 10 t / h. A burner that burns wood biomass powder (20 kg / min) as a heating source, and the maximum surface temperature of bamboo at the roasted portion was 310-390 ° C. The residence time in the roasting part is 20 minutes. Regarding the 2 mm surface layer of the bamboo after the treatment, the moisture content was 4% and the decomposition rate of hemicellulose was 95%. As an average composition of bamboo, when the average diameter was 30 mm, the water content was 6%, and the decomposition rate of hemicellulose was 35%.

  The wood roast made by the method of Example 1 and the bamboo roast made by the method of Example 3 were mixed at a weight ratio of 85:15 and pulverized. Then, the mixed pulverized product was molded into briquettes having an average diameter of about 25 mm with a roll molding machine of 300 to 500 kg / cm2) at room temperature. The crushing strength was 18-25 kgf.

  The crushed wood raw material shown in Example 1 was mixed at a weight ratio of 80 and the crushed bamboo raw material of Example 3 was mixed at a ratio of 20 by weight, and baked in the case 2 method of FIG. The preheating part is a vertical type and the roasting part is a kiln type. The charging speed of the mixed raw material is 15 t / h. The heating source was a burner that was generated in the roasted portion and burned the hemicellulose decomposition gas, and the maximum surface temperature of the surface layer of the object to be heated was 370 to 420 ° C. The residence time in the roasting part is 30 minutes. The resulting mixture was ground. Then, the mixed pulverized product was molded into briquettes having an average diameter of about 25 mm with a roll molding machine of 300 to 500 kg / cm2) at room temperature. The crushing strength was 17-23 kgf.

  The molded product produced by the method of Example 5 was transported to a coal-fired power plant 55 km away by truck, added with 7 wt% of coal, pulverized, and then burned in a steam boiler. There was no particular problem when transporting conveyors, and stable operation was possible.

The molded product produced by the method of Example 4 was transported to an iron mill 150 km away by truck and railroad, and after primary crushing, a portion of 2 mm or less (water content 5%) was 1 by weight, fine powder A mixture of charcoal at a weight ratio of 1 was blown from the blast furnace tuyere at an oxygen hatching rate of 3%. The amount of blowing is 80 kg / min. The tuyere temperature was in the range of 2010-2030 ° C, compared to 2030 ° C in the comparative example not using woody biomass.

  The molded product manufactured by the method of Example 4 and transported to the steel mill was pulverized to 2 mm or less. The water content was 5%. This was mixed at a weight ratio of 10, pulverized coal at a weight ratio of 85, and coal tar soft pitch at a weight ratio of 5 and formed into a Macek mold having a width of 43 mm, a length of 25 mm, and a thickness of 18 mm through a double roll molding machine. This was carbonized at 1000 ° C. to produce coke. As a result of measuring the obtained coke strength with JIS drum strength D130 / 15, the difference was in the range of plus 1% to minus 3% compared to the comparative material (without blending woody biomass).

  What was manufactured by the method of Example 5 was conveyed to the steel mill, and it grind | pulverized so that an average diameter might be set to 2.5 mm or less with the grinder. The water content is 5%. The steelmaking furnace is a 150 ton scale top blowing converter, which is filled with hot metal and starts 3.5 minutes after starting pure oxygen blowing and 2.5 minutes before the end of pure oxygen blowing (that is, pure oxygen blowing) (From 3.5 minutes to 19.5 minutes after starting), the converter exhaust gas in which the granular material was stored was blown in as a carrier gas in a horizontal direction from a position 15 cm from the lower end of the duct. The powder supply rate was blown at 80 kg / min. The components of the obtained gas were about 78% carbon monoxide, about 4% carbon dioxide, hydrogen: 12%, nitrogen: 5% (comparative; carbon monoxide without using woody biomass; 75% Carbon dioxide; about 13%, hydrogen; 2%, nitrogen 7%). The amount of fuel gas recovered was 1.24 times that of the comparative heat.

  By the present invention, felled trees generated by forest management necessary to maintain the carbon absorption capacity of trees at a high level are linked to thermal power plants and steel industry, which are representative industries that use large amounts of fossil energy. Including transportation, it can greatly contribute to the prevention of global warming. In addition, by improving the economics of wood quality as a whole system, it can contribute to the promotion of the forestry industry that enhances the international competitiveness of domestic wood quality.

Claims (5)

  The first step of converting woody biomass into a piece of wood so that the average diameter is 40 mm or less, the second step of heating the piece of wood so that the surface layer part is 250 ° C. or more and 450 ° C. or less, and crushing bamboo to make the surface layer part 250 4th step of mixing and molding the product obtained in the 3rd step and the 2nd step, heating in 3rd step and 2nd step, heating to 450 ° C or less, and using the transported one as energy source Effective use of woody biomass as an energy source, characterized by comprising the fifth step of   The method for effectively using woody biomass as an energy source, wherein the ratio of adding bamboo crushed and processed in the fourth step of claim 1 is in the range of 5 to 30% of the whole   The method of effectively using woody biomass, wherein the step of utilizing as an energy source in the fifth step of claim 1 is co-firing in a coal-fired power plant   The process used as an energy source of the fifth process of claim 1 is a steelmaking process of a steel mill, and pulverized wood biomass that has been transported and blown from a blast furnace blade or mixed with coal and molded A method for effectively using woody biomass, which is charged in a coke oven and charged into a blast furnace as a coke molding   The method of effectively using woody biomass, wherein the step of utilizing as an energy source in the fifth step of claim 1 is a steelmaking step of a steel mill, and the pulverized product is blown into high-temperature exhaust gas of a converter.

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