JPS59192094A - Pretreatment for treatment of biomass with enzyme - Google Patents

Abstract

PURPOSE:To pretreat continuously a biomass for liquid fuel or chemical raw material in a short time, by feeding the biomass to a twin-screw extruder, adding an aqueous solution of an alkali compound to the extruder during feeding. CONSTITUTION:A biomass (e.g., bagasse, Japanese beech, silver fir, oil paper, etc.) having preferably <=30mm. average particle diameter is fed to a twin-screw extruder, an aqueous solution of an alkali compound such as NaOH, Na2S, etc. is added to the extruder, the biomass is blended with the aqueous solution preferably at 60-230 deg.C, kneaded and reacted.

Description

Detailed Description of the Invention The present invention relates to continuous pretreatment of biomass for #water treatment, and more specifically, biomass is introduced into a twin-screw extruder, and an alkaline reagent aqueous solution is separately injected into the extruder, in which biomass and alkaline The present invention relates to a continuous pretreatment method for enzymatic treatment of biomass, which is characterized by contacting reagents and causing a crosstalk reaction.

In the wake of the oil crisis of 1971, the so-called first oil shock, woodcutters have been reviewing alternative resources and developing utilization techniques in order to avoid excessive dependence on fossil resources. Among these, biomass as a renewable resource is attracting attention, and its utilization technologies are being considered. Cellulose, which is the main component of biomass, is decomposed enzymatically or chemically into glucose, and then fermented to obtain jetanol, which is used as a liquid fuel or chemical raw material. The (IJR) decomposition method of cellulose has the advantage that it can be carried out under milder conditions than the chemical decomposition method and does not require complicated equipment, but it also has the following drawbacks. It is difficult to receive the action of enzymes.

■Reaction is slow. ■Enzyme preparation requires a lot of money, and it is difficult to recover and reuse it. Conventional pretreatment methods for enzymatic decomposition of biomass include pulverization treatment and alkaline steaming treatment, but both require considerable cost and processing time and are therefore not practical.

Among them, the patent application filed earlier by the inventors in 1980-80
98.仝80,999(JP-A-57-198094,
廝-193095) (hereinafter referred to as the prior invention) is essentially a combination of pulverization treatment and alkaline steaming, and the treatment time is short, for example, from 0.25 to 4.0 hours.
The enzymatic decomposition rate of pretreated products is, for example, 86.1 to 96.4%.
It's as good as it gets. However, although the pretreated product according to the prior invention has a high enzymatic decomposition rate, the problem is that the processing time is still insufficient. For this reason, the present inventors conducted extensive research on a pretreatment method that would improve the saccharification rate of pretreated products for decomposition of biomass by cellulase enzymes, and succeeded in continuous pretreatment of biomass using a twin-screw extruder, thereby developing the present invention. completed.

The present invention is a continuous pretreatment method for enzymatic treatment of biomass, which is characterized by introducing biomass into a twin-screw extruder, and then contacting, kneading, and reacting with a water bath solution containing an alkaline compound. The method described above involves cutting and pulverizing biomass into pieces with a length of 39 mm or less, or injecting an aqueous solution of an alkaline compound in an amount of 3 to 15'4i times the amount of biomass into an extruder, and The above method in which the weight ratio of biomass is 8 to 80%, the above method in which the processing temperature of the twin screw extruder is 60 to 280 ° C., the biomass is bagasse, beech, magnolia, birch, rainbow pine, corn cob, Alternatively, the method includes the above method in which the alkaline compound is NaOH, Na2S or a mixture thereof.

The structure and effects of the present invention will be explained in detail below.

In principle, any biomass cellulose resource can be used as the raw material of the present invention. However, since the present invention involves an efficient pretreatment method, the form of the biomass becomes an issue.

Regardless of whether the resource is woody or herbaceous, it must be cut or crushed into appropriate dimensions. The shape of the particles is such that the average particle size is 30 particles or less, preferably 15 sta or less, in order to facilitate insertion into the screw of a twin-screw extruder.

Regarding the types of biomass, there are woody materials such as beech, magnolia, birch, and rainbow pine, or bagasse and rice straw.

Herbaceous materials such as wheat straw and corncobs.

Any cellulosic material such as waste paper can be used. Bagasse is already crushed and pressed at the sugar factory, so there is no need to crush it again.

1. Aqueous solution of alkaline compound used in the present invention Use 3 to 15 times the weight of biomass.

If it is less than 3 times the weight, rapid and uniform mixing and penetration will be difficult, and if it is more than 15 times the weight, there will be no particular improvement in the effect. NaOH is used as an alkaline reagent.

Na2S or its mixture to biomass
Use 30% by weight. If the amount of the drug used is less than the above-mentioned amount range, the pretreatment effect of the present invention will be reduced, and if it is used in a range exceeding the above range, there will be no particular effect. Any of NaOH, Na2S, and a mixture thereof may be effective as the reagent used, and the ratio of the mixture may be arbitrary, but preferably NaOH/Na2S (weight ratio) is used at 1 to 5 times.

C. Inject the dialkaline compound through the feed port or vent under pretreatment conditions, knead, and react. For the introduction, plastic pellets or twin screw feeders commonly used for powder extrusion can be used.

A twin screw extruder is used as the extruder. Single-screw extruders lack kneading and extrusion capabilities and are unsuitable for biomass pretreatment.

The screws may rotate in the same direction or in different directions. Processing temperature (extruder cylinder temperature) is 60-23
0°C, preferably 90 to 230°C. The biomass is introduced into the extruder, mixes with the medicinal solution of the alkaline compound, reacts with it, and is discharged from the trench where the residence time, ie, the pretreatment time, is short, less than 1 minute.

29.Characteristic Effects of the Present Invention As is clear from the above description, the advantage of the present invention is that continuous processing can be carried out in an extremely short pretreatment time. In other words, in the conventional pretreatment method, for example, in the pulverization process, 5
In order to obtain an enzymatic decomposition rate of 0% or more, a pulverization treatment time of several hours to several tens of hours is required, and for example, in an alkali treatment, a steaming time of several tens of minutes to several hours is required. Furthermore, when the biomass is introduced into the extruder, it is still mixed with the aqueous alkaline chemical solution, making it easy to introduce the biomass into the extruder.

Next, the present invention will be explained with reference to Examples.

Tests in Examples were conducted in the following manner.

(1) Enzyme degradation rate and enzymatic saccharification rate Sample 1%, enzyme 1%, 0.1M acetate buffer (]) H5
, 0), and mono-shaking (46 strokes/min) was carried out at 50°C for 4 hours using an L-shaped test tube (18 mm diameter, 100 mm height x 120 mm length). The enzyme is Cellulase Onozuka R-10 (Trichoderma Vi
ride cellulase (Yakult Biochemicals) was used. After the reaction, the enzyme reaction solution was separated using glass fiber r paper (Toyo Roshi Gc-5o), and the filtration residue was thoroughly washed with water and heated at 105°C.
After drying at C overnight, it was ground and the enzymatic decomposition rate was calculated using the following formula.

Glucose in the filtrate was measured, and the enzymatic saccharification rate was calculated using the following formula.

Glucose produced x 09 Enzyme saccharification rate = (1 - sample (dry matter) -) x 100 (
2) Lignin According to JIS P 8008 (1976) Lignin test method for pulp materials.

Examples 1 to 6 Introducing bagasse crushed to lengths of 30 or less, NazS-
A 4% aqueous solution of NaOH was injected through the vent hole, causing crosstalk and reaction. The treatment was carried out at an extruder cylinder temperature of 200°C. After processing, bagasse'f: filtered, washed and washed with acetone,
The lignin content and enzymatic decomposition rate of the air-dried bagasse were measured using a predetermined test method. Table 1 shows the results.

Note that the method of the present invention and the method of the prior invention have different steaming conditions and cannot be easily compared. The former is inferior to the latter in both lignin content and enzymatic decomposition rate. However, the enzymatic saccharification rate, which is the final deciding factor, is comparable to that of the prior invention.

On the other hand, the processing time is extremely short, less than 1 minute, compared to 15 minutes or more in the prior invention.

Examples 7 to 12 The same process as in Example 3 was carried out except that the Na2S-NaOH concentration was changed. Table 2 shows the results.

Table 2 Notes NazS: NaOH=3:7 Example 1.
8 to 14 The samples were treated in the same manner as in Example 3 except that the sample particle size was changed.

Table 3 shows the results.

Table 8 Note *Na2S-Na0H=8-7 Examples 16-20 The treatment was carried out in the same manner as in Example 1 except that the temperature was changed.

Table 4 shows the results.

Table 4 Examples 21-24 15n of beech, birch, rainbow pine, and corncob
The pulverized and sieved samples were processed as follows. Table 5 shows the results.

Claims (6)

[Claims] (1) A biomass enzyme characterized by supplying biomass to a twin-screw extruder, injecting an aqueous solution of an alkaline compound into the machine during the supply, and kneading and reacting the biomass and the aqueous solution in the machine. Pretreatment method for treatment. (2) The pretreatment method according to claim (1), which uses biomass with an average particle size of 30Wn11 or less. (3) The pretreatment method according to claim (1), wherein an aqueous solution of an alkaline compound is used in an amount of 3 to 15 times the weight of the biomass, and the compound is used in an amount of 8 to 30% by weight based on the biomass. (4) Processing temperature in the twin-screw extruder is 60 to 280°
The pretreatment method according to claim (1), which is C. (5) Biomass is bagasse, beech, magnolia, rainbow pine,
The pretreatment method according to claim (1), which is birch, corn cob, or waste paper. (6) The pretreatment method according to claim (1), wherein the alkalinity is NaOH, Na2S, or a mixture thereof.