Methods for compressing cellulose-based biomass and methods for preparing gas fuel.

Abstract

This invention relates to a method of squeezing biomass based on... Cellulose-based biomass: a method that includes crushing cellulose-based biomass; A pre-determined conditioning process is performed on cellulose-based biomass; and subsequently, Compressing cellulose-based biomass where conditioning includes dehydration procedures. It is incorporated into cellulose-based biomass and the discharge process is carried out by releasing the biomass. The cellulose base is left behind after the water is added and it is left to stand for a specified period of time;

Description

The present invention relates to a method for squeezing cellulosic biomass and a method for converting it into gaseous fuel. This application claims priority based on Japanese Patent Application No. 2014-208796 filed in Japan on October 10, 2014, the content of which is incorporated herein. As is well known, palm oil is a vegetable oil extracted from the fruit of the oil palm (Japanese name: oil palm). Such palm oil is mainly produced in Southeast Asia and is manufactured in large-scale plantations. For example, Patent Document 1 below discloses a method (squeezing method) of treating the trunk (trunk) of the oil palm as biomass (biological resource) and squeezing sap (sugar-containing liquid) from the trunk. there is Further, this patent document 1 discloses a shredder for a trunk used in the juice squeezing method, and a juice squeezing system provided with this shredder for trunk and a squeezing device. On the other hand, Patent Document 2 below also discloses a method of collecting sap from a trunk (sap collection method). Such techniques for squeezing trunks are intended to produce ethanol (bioethanol) and lactic acid through alcoholic fermentation and lactic acid fermentation using the sugar contained in oil palm sap as a raw material. In other words, at present, the percentage of the total sap contained in the trunk that can be separated by squeezing is not sufficient, and the sap that cannot be separated must be discarded together with the sap of the trunk. Therefore, utilization of the trunk as biomass is not sufficient. Japanese Patent No. 4665257 Japanese Patent No. 4418871 However, with the techniques of Patent Document 1 and Patent Document 2, the sap squeezing rate is not always sufficient, so there was no cost advantage in putting ethanol and lactic acid manufacturing plants into practical use. That is, at present, the percentage of the total sap contained in the trunk that can be separated by squeezing is not sufficient, and the unseparated sap is discarded together with the trunk. Therefore, in the technical field related to squeezing oil palms or plants of the palm family (palm plants) containing the oil palms, it is necessary to further improve the sap squeezing rate in order to effectively utilize palm plants as biomass. is a big technical problem. The present invention has been made in view of the above circumstances, and aims to improve the sap squeezing rate of various cellulosic biomass containing cellulose and hemicellulose such as palm plants. A first aspect of the method for squeezing cellulosic biomass of the present invention is a method for squeezing cellulosic biomass, in which cellulosic biomass is crushed, subjected to a predetermined pretreatment, and then squeezed, The pretreatment includes a hydration treatment of adding water to the cellulosic biomass and a leaving treatment of leaving the cellulosic biomass after the hydration treatment for a predetermined period of time. A second aspect of the method for squeezing cellulosic biomass of the present invention is, in the above-described first aspect, in the water treatment, addition is performed according to the COD (Chemical Oxygen Demand) concentration of the cellulosic biomass measured in advance. Water volume is set. A third aspect of the method for squeezing cellulosic biomass of the present invention is the above first or second aspect, wherein the standing treatment is performed so that the COD (Chemical Oxygen Demand) concentration of the water added to the cellulosic biomass is Terminate when a predetermined threshold is exceeded. A fourth aspect of the method for squeezing cellulosic biomass of the present invention is the cellulosic biomass in any one of the first to third aspects above, wherein the cellulosic biomass is the trunk of an oil palm. According to the first aspect of the method for converting cellulosic biomass into gaseous fuel of the present invention, the sap obtained by any one of the first to fourth cellulosic biomass squeezing methods is subjected to methane fermentation. A second aspect of the method for converting cellulosic biomass into gaseous fuel of the present invention is the first aspect, wherein the slag from which the sap is separated by the squeezing is subjected to saccharification, and the sap is obtained by the saccharification. The obtained saccharified liquid, or the saccharified liquid and the sap are subjected to methane fermentation. According to the present invention, since the pretreatment for the squeezing treatment includes the hydration treatment of adding water to the cellulosic biomass and the standing treatment of leaving the cellulosic biomass after the hydration treatment for a predetermined period of time, cellulose such as palm plants It is possible to improve the sap extraction rate of sap contained in various cellulosic biomass including hemicellulose and hemicellulose. 1 is a flow chart showing processing steps of a method for squeezing cellulosic biomass according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the tissue morphology of a palm trunk X1 in one embodiment of the present invention; It is a graph which shows the squeezing rate (COD elution rate) in one embodiment of the present invention. An embodiment of the present invention will be described below with reference to the drawings. The method for squeezing cellulosic biomass according to the present embodiment targets the trunk of oil palm (palm trunk X1), which is a kind of cellulosic biomass, and consists of steps S1 to S5 in FIG. Further, the method for converting cellulosic biomass into gaseous fuel according to the present embodiment utilizes such a method for squeezing cellulosic biomass, and consists of steps S1 to S9 in FIG. The palm trunk X1 is an old tree from which a sufficient amount of fruit, which is a raw material for palm oil, has been harvested. As shown in FIG. there is The vascular bundle A is a bundle-like tissue that penetrates the palm trunk X1 in the axial direction, and is in charge of transporting liquids such as water and nutrients and mechanically supporting the palm trunk X1. On the other hand, the soft tissue B is tissue positioned between the vascular bundles A in the direction orthogonal to the axial direction of the palm trunk X1, that is, tissue that bonds the vascular bundles A together. This soft tissue B, when enlarged, is an aggregate of tissues (bag-like tissue) formed in a bag shape as shown in FIG. The sap and starch containing sugars (free sugars of pentose and hexose) are contained so as to be wrapped inside the bag-like tissue. Further, this soft tissue B is a tissue having a high water retention capacity due to its bag-like shape. Such a palm trunk X1 is a cellulosic biomass containing nearly 80% water, and contains the vascular bundle A and soft tissue B at a ratio of about 50% as components other than water. In the first step, the chipping process S1 (crushing process), such a palm trunk X1 is crushed into small pieces of a predetermined size using a crusher. That is, in this chipping process S1, for example, a log-shaped palm trunk X1 having a diameter of 30 to 60 cm and a length of about 10 m is crushed into chips (palm chips X2) having a maximum dimension of about 2.0 to 8.0 cm. . The crusher used in this chipping process S1 does not have to be a special machine, and any machine can be used as long as it can crush the palm trunk X1 into small pieces. Also, instead of chipping the palm trunk X1, the palm trunk X1 may be cut into small pieces, shredded, or peeled. In the COD concentration measurement process S2, which is the second step, the COD (Chemical Oxygen Demand) concentration (mg / l) of the palm chip X2 is measured. That is, in this COD concentration measurement process S2, sap is collected from the palm trunk X1 by using a predetermined compressor, and the COD concentration of this sap is measured. This COD concentration is an index indicating the concentration (sugar concentration) of the sugar solution contained in the palm chips X2. Therefore, when measuring on-site, in addition to the COD concentration, it is recommended to use a Brix saccharimeter, a glucose meter, a simple organic matter measurement kit, or a sugar content measurement kit based on pigment change to quickly measure the sugar content and organic matter concentration. It may be measured with a measuring device or kit that can measure on time. It should be noted that this sugar concentration changes depending on the growth state and growth period of the palm trunk X1 before felling. The COD concentration used in the present application is CODCr measured by potassium dichromate. In the water treatment S3, which is the third step, a predetermined weight of water (dilution water) is added to the palm chips X2. The weight (addition amount) of this dilution water is determined according to the COD concentration (sugar concentration) of the sap measured by the COD concentration measurement process S2. That is, in this hydration treatment S3, the higher the COD concentration of the sap in the raw palm trunk X1, the more dilution water is added to the palm chips X2 to form the hydrated palm chips X3. Although the details will be described later, the amount of dilution water added is limited to some extent in relation to the methane fermentation process S8 in the latter stage. Further, the dilution water does not have to be normal temperature water, and preferably, it may be warm water that is warmer than normal temperature. The temperature of the heated water is not particularly limited, but a too high temperature is not preferable in terms of energy efficiency. In the leaving process S4, which is the fourth step, the hydrated palm chips X3 are left for a predetermined period of time. That is, in this leaving process S4, the palm chips X2 in a state of being immersed in the diluted water are left for a certain period of time. The sap concentration of the palm chips X2 immediately after the addition of the dilution water is naturally lower than the sap concentration in the dilution water (0% immediately after the addition), but due to the osmotic pressure caused by the concentration gradient of this sap, the sap concentration in the palm chips X2 The sap dissolves into the dilution water. As a result, the sap concentration in the dilution water gradually increases over time. In some cases, stirring may be performed to actively promote elution. The contents may be stirred artificially, or the inside of the tank may be slowly stirred mechanically. It is also possible to circulate the added water. In short, any method may be used as long as the sap concentration in the dilution water is increased in a short period of time. Table 1 shows the CODCr concentration [mg / l] of the dilution water, the elution amount of sap in the dilution water (COD elution amount [g]), and the sap elution rate (COD elution rate [%]) in this standing treatment S4. It is a table showing an example. In addition, FIG. 3 is a graph of the COD elution rate [%] in Table 1. In this example, 400 g of dilution water (pure water) was added to 200 g of palm chips X2. In other words, the weight ratio of palm chips X2 and dilution water is 1:2, and the relationship between elapsed time [hr], CODCr concentration [mg / l], COD elution amount [g] and COD elution rate [%] is confirmed. bottom. The ambient temperature at this time was 25 to 28°C. As shown in Table 1 and FIG. 3, 12 hours after the dilution water was added to the palm chips X2, the COD elution rate increased to 78.7%, and then showed a downward trend after slightly increasing. The maximum COD elution rate was 84.1% after 48 hours and 72 hours. Table 1 shows the CODCr concentration and COD elution amount at each elapsed time. In this experiment, data was not obtained for an elapsed time shorter than 12 hours, but the COD elution rate was relatively low immediately after adding the dilution water to the palm chip X2, judging from the overall trend of change described above. It is estimated that it will exceed 70% in a short time. Here, the COD concentration measurement process S2, the hydration process S3, and the standing process S4 are performed when the palm chips X2 obtained in the chipping process S1 are processed in the subsequent squeezing process S5, that is, the sap is separated from the palm chips X2.・Positioned as a pretreatment F when collecting. That is, the COD elution rate in Table 1 and FIG. 3, which is the result of the standing treatment S4, indicates the sap squeezing rate obtained based on the pretreatment F. In such pretreatment F, by appropriately measuring the CODCr concentration of the hydrated palm chips X3 in the standing treatment S4, when the COD elution rate exceeds a predetermined threshold (for example, 80%), the hydrated palm chips X3 end the abandonment of That is, the standing time in the standing process S4 is determined based on the CODCr concentration that gradually increases while the hydrated palm chips X3 are left standing. In addition, by using warm water instead of room temperature water as the dilution water in the hydration treatment S3, the temperature gradient between the sap and the dilution water is used in addition to the concentration gradient of the sap. It is possible to improve the COD elution rate, that is, the sap rate separated from the palm chips X2. In the squeezing process S5, which is the fifth step, the treatment liquid of the leaving process S4, that is, the left-hydrated palm chips X4 are solid-liquid separated. That is, in this squeezing process S5, for example, by using a centrifugal separator or a squeezing device, the mixed liquid X5 of the diluting water and the sap eluted from the palm chips X2 is separated from the solid content of the palm chips X2 (squeeze X6). be. The mixed liquid X5 is sap-mixed water having a CODCr concentration as shown in Table 1 due to the pretreatment F described above. In addition, as a separation device used in the juice squeezing process S5, a screen device such as a rotary screen may be used instead of the centrifugal separator or the pressing device. According to the juice squeezing method according to the present embodiment, a series of processes consisting of the above-described pretreatment F, that is, the COD concentration measurement process S2, the water treatment S3, and the standing process S4 is adopted, so the It is possible to achieve a COD elution rate (sap extraction rate). In addition, since the process required for sap extraction is extremely simple, the cost required for sap extraction can be kept low. Here, Table 2 shows Comparative Examples 1 to 4 for the juicing method according to this embodiment. That is, in these Comparative Examples 1 to 4, the CODCr Concentration [mg / l] and COD recovery rate [%] are shown. In Comparative Example 1, a 500 g sample with a weight ratio of palm chips X2 and dilution water of 1:2 was cut with a wet cutter manufactured by Masuko Sangyo (number of blades: 14, opening 1.3 mm), It relates to the supernatant obtained by centrifugation. In Comparative Example 2, in addition to breaking the sample with a wet cutter manufactured by Masuko Sangyo (number of blades: 14, opening 1.3 mm), a wet mill manufactured by Masuko Sangyo (clearance: 160 μm, rotation speed: 1500 rpm), and then centrifuged to obtain the supernatant. Comparative Example 3 relates to the supernatant obtained by changing the clearance 1 of the wet mill in Comparative Example 2 from 160 μm to 80 μm and centrifuging. Furthermore, in Comparative Example 4, the grinding treatment by the wet mill was performed twice, that is, the clearance was set to 240 μm and the rotation speed was set to 3000 rpm in the first time, and the clearance was set to 80 μm and the rotation speed was set to 1500 rpm in the second time. It relates to a supernatant liquid obtained by performing trituration treatment with and centrifuging treatment. In such Comparative Examples 1 to 4, the highest COD recovery rate (sap sap rate) is 75.1% in Comparative Example 3, but this 75.1% is due to the squeezing method according to the present embodiment. It is significantly lower than the COD elution rate (sap extraction rate) in Therefore, the squeezing method according to the present embodiment is a highly efficient squeezing method for squeezing the sap from the palm trunk X1. Next, in the sixth step, saccharification treatment S6, the lees X6 (squeezed bacchus) obtained in the squeezing treatment S5 are hydrolyzed to solubilize (monosaccharify and / or free saccharify). In this saccharification treatment S6, monosaccharides such as pentose and hexose are produced by hydrolyzing the pomace X6 based on, for example, an enzymatic saccharification method or a microbial saccharification method. As is well known, cellulosic biomass such as palm trunk X1 or woody biomass is mainly composed of cellulose, hemicellulose and lignin. In the enzymatic saccharification method, among these main components, cellulose and hemicellulose are hydrolyzed in the presence of saccharifying enzymes. It is conceivable that starch granules contained in the parenchyma B of the palm trunk X1 remain in the pomace X6, and such starch granules can be sufficiently hydrolyzed in the presence of amylase or glucoamylase. It should be noted that the "saccharification treatment" in the present embodiment does not necessarily decompose cellulose or hemicellulose into monosaccharides or free sugars. Furthermore, cellulose or hemicellulose may be further decomposed than monosaccharides or free sugars. That is, in the saccharification treatment S6, the cellulose in the pomace X6 is hydrolyzed to produce hexose, while the hemicellulose in the pomace X6 is also hydrolyzed to produce pentose. The monosaccharides (pentoses and hexoses) produced by such hydrolysis are water-soluble and therefore dissolve in water. Therefore, the saccharified liquid X7 obtained by the saccharification treatment S6 is a solid-liquid mixed water composed of a solid mainly composed of lignin and a saccharified liquid X8 in which monosaccharides are dissolved in water. Moreover, the saccharification treatment may be a microbial saccharification method using Clostridium thermocellum. In particular, the inventors found that a co-culture system of Clostridium thermocellum and Thermoanaerobacter brockii yielded 62.5% glucan and 39% xylan degradation. Therefore, the co-culture system of Clostridium thermocellum and Thermoanaerobacter brockii enables highly efficient saccharification. In the solid-liquid separation process S7, which is the seventh step, the saccharified liquid X7 is subjected to solid-liquid separation. That is, the saccharified liquid X8 is separated from the saccharified liquid X7 by using a solid-liquid separation device such as a centrifuge. Then, this saccharified liquid X8 is provided as a raw material to the subsequent methane fermentation treatment S8. In the methane fermentation process S8, which is the eighth step, biogas X9 whose main components are methane gas and carbon dioxide is generated by methane fermentation using the mixed liquid X5 (sugar liquid) and the saccharified liquid X8 as raw materials. Methane fermentation, as is well known, is an anaerobic decomposition of organic matter, in other words, by decomposing organic matter through the action of methane bacteria, which are anaerobic microorganisms, digestion gas (biogas), which is mainly composed of methane gas and carbon dioxide, is generated. It is a reaction system that causes Here, in the methane fermentation process S8, it is necessary to maintain the activity of the methane bacteria by heating the mixture X5 (sugar solution) and the saccharified solution X8, which are raw materials for methane fermentation, to some extent. Considering the energy efficiency, it is preferable that the mixed liquid X5 (sugar liquid) and the saccharified liquid X8 have a high sugar concentration. And from such a background, when obtaining the liquid mixture X5, the addition amount of the dilution water added to the palm chip|tip X2 by hydration process S3 is restrict|limited. In the power generation process S9, which is the ninth step, power is generated by driving the internal combustion engine using the biogas X9 as fuel. That is, in the power generation process S9, power is generated by burning the biogas X9 in the combustor, and power is generated by driving a generator with this power. The electric power generated in the power generation process S9 is used, for example, to operate power sources such as the chipping process S1 and the water adding process S3. According to the gaseous fuel conversion method according to the present embodiment, the sap sap squeezing rate can be improved more than before by the squeezing method according to the present embodiment, so biogas X9, which is a gaseous fuel, is generated. Efficiency can be improved more than before. Therefore, according to the present embodiment, highly efficient sap extraction and generation of biogas X9 can be realized. It should be noted that the present invention is not limited to the above embodiments, and for example, the following modifications are conceivable. (1) In the method for squeezing cellulosic biomass and the method for converting cellulosic biomass into gaseous fuel according to the above-described embodiments, palm trunk X1, which is a kind of cellulosic biomass, was targeted for squeezing, but the present invention is limited to this. not. Cellulosic biomass having sap containing sugar includes palm petiole, banana, sugar cane, corn, cassava, sago palm, nipa palm, yam, sorghum, potato, banana stem and leaves, cellulose and sap ( or juice), and crops composed of cellulose / starch / sap (or juice). (2) In the above embodiment, the COD concentration of palm chips X2 (that is, palm trunk X1) is measured in advance, and the amount of water added is set according to the measured value, but the present invention is not limited to this. For example, the amount of water added may be a fixed value. (3) In the above embodiment, the standing of the hydrated palm chips X3 is ended based on the CODCr concentration [mg / l] of the hydrated palm chips X3, but the present invention is not limited to this. For example, when the standing time specified as a fixed value has passed, the standing of the hydrated palm chips X3 may be terminated unconditionally. (4) In the method for converting cellulosic biomass into gaseous fuel according to the above embodiment, the saccharified liquid X8 was obtained from the lees X6 by performing the saccharification treatment S6 and the solid-liquid separation treatment S7, but the present invention is not limited to this. . By eliminating the saccharification process S6 and the solid-liquid separation process S7, only the liquid mixture X5 may be supplied to the methane fermentation process S8 as a raw material. According to the present invention, it is possible to improve the sap squeezing rate of various cellulosic biomass containing cellulose and hemicellulose such as palm plants. X1 Palm stem (cellulosic biomass) X2 Palm chips X3 Hydrated palm chips X4 Left hydrated palm chips X5 Mixed liquid X6 Squeezed lees X7 Saccharified liquid X8 Saccharified liquid X9 Biogas (gaseous fuel)

Claims

Revised 20 / 08 / 2019, No claims ---------------------------------------------------------------------------------------------------- Revised 05 / 10 / 2018, No claims ---------------------------------------------------------------------------------------------------- 1. Method of squeezing cellulose-based biomass: A method comprising the crushing of the cellulose-based biomass, a pre-conditioning operation on the cellulose-based biomass, and subsequent squeezing of the cellulose-based biomass, where the pre-conditioning includes a dehydration operation by adding water to the cellulose-based biomass, and a settling operation by leaving the cellulose-based biomass to stand for a specified period after dehydration.

2. Method of squeezing cellulose-based biomass as per claim 1, where in the dehydration operation the amount of water added depends on the pre-measured chemical oxygen demand (COD) of the cellulose-based biomass. 3.

1. Cellulose-based biomass pressing methods under Reputation 1 or 2 where the release operation is stopped when the COD concentration of water added to the cellulose-based biomass exceeds a predetermined threshold.

4. Cellulose-based biomass pressing methods under either Reputation 1 or 3 where the cellulose-based biomass is oil palm trunks.

5. Gas fuel preparation methods using cellulose-based biomass where methane fermentation is carried out with the sludge obtained by cellulose-based biomass pressing methods under Reputation 1 to 4.

6. Cellulose-based biomass pressing methods under Reputation 5 where strained lees from sludge separation by the pressing process are subjected to saccharification, and the resulting saccharified solution and saccharified solution and methane fermentation are then used.