JPS5991893A - Method for pretreating cellulosic raw material for saccharification - Google Patents

Abstract

PURPOSE:To minimize the consumption of power and an alkali and pretreat the titled raw material efficiently and continuously under ordinary pressure, by using the mechanical pulverization treatment and alkali treatment in combination. CONSTITUTION:(i) A cellulosic raw material 1 for saccharification, e.g. rice straw, is roughly crushed by a cutter 2 and a rough crusher 3 to pieces having 1-100mm. length and 1-20mm. width, which are then passed through a hopper 4, vibrating feeder 5, metering machine 6 and belt conveyor 7 and fed to a solid- liquid countercurrent contact apparatus 8. (ii) The roughly crushed raw material is then brought into contact and treated with an aqueous alkaline solution, e.g. aqueous solution of caustic soda in <=1mol concentration, in the former stage and then washed with water in the latter stage to remove the alkali. (ii) The raw material is then passed through a hopper 9 and wet pulverized in a pulverizer 10, e.g. a colloid mill.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for pre-treating cellulosic raw materials for saccharification.

When saccharifying cellulose raw material I'11, pretreatment of the raw material is necessary, and conventionally, mechanical crushing using a crusher, steaming treatment, or alkali treatment have been used as pretreatment methods for cellulose raw material for saccharification. It has been adopted.

However, conventional mechanical crushing methods require a large amount of crushing power. Since the alkaline treatment method consumes a large amount of alkali and is treated at high temperature (pretreatment at around 120° C. has high saccharification properties), the equipment requires pressure-resistant equipment and is difficult to operate continuously. Therefore,
This has the disadvantage that the processing equipment is large.

This invention was made in order to solve the disadvantages of the conventional method, and it reduces the power consumption and alkali consumption for pulverization as much as possible, and also pre-treats the cell base material for saccharification under normal pressure. It is intended for continuous processing.

This invention provides a pretreatment method for cellulosic raw materials for continuous saccharification, which combines R-mechanical pulverization and alkali treatment.

That is, in this invention, when saccharifying a cellulosic raw material, the length of the raw IFI+ is 1 to 100 m+n.

The crushed raw material is crushed to a diameter or width of 1 to 20 mm.
hydroxide of an alkali metal or alkaline earth metal with a concentration of 1M0L or less without heating or humidifying 'l under normal pressure,
Sulfide, charcoal Fl! Saccharification in which dealkalization is carried out by contacting with one weight of an aqueous solution or a mixed aqueous solution of two or more weights selected from aqueous solutions of 2 salts or sulfites, and the dealkalized raw material R1 is wet-pulverized. This is a pretreatment method for cellulosic raw materials for industrial use.

The method of the present invention achieves an improved pretreatment effect by combining mechanical pulverization and alkali treatment, and the drying step is omitted since the alkali treatment is followed by wet pulverization. Due to the reduction in silica, lignin, etc., the power consumption per unit weight of pulverized material can be significantly reduced. Moreover, since the alkali treatment causes heavy loss of solid phase (due to removal of lignin, ash, etc.), the total power consumption required for pulverization can be significantly reduced, and the saccharification residue can also be significantly reduced.

In addition, in the method of the invention L:, a cutter and/or a coarse pulverizer can be used in an appropriate combination depending on the type of cellulose base r1 for saccharification, and the alkali treatment and dealkalization treatment are carried out at 100°C or lower, that is, under normal pressure. Since it can be carried out with
Continuous operation was made possible using a solid-liquid countercurrent contact device. Therefore, it was possible to reduce the amount of alkali consumption and downsize the apparatus, and a high saccharification property of the cellulose raw material r1 was obtained.

Next, a detailed explanation of this invention will be given with reference to the drawings. Ru.

FIG. 1 is a process diagram of the present invention, and the pretreatment of the cellulose-based 11ilii grain for saccharification consists of cutting and/or coarse pulverization, alkali treatment, dealkalization treatment, and fine pulverization steps.

FIG. 2 is a schematic diagram of the invention.

Cutter 2 and/or coarse grinder 1! Cell for saccharification with i3 [length of 1-su type raw material 1 is 1 to 100+nyn].

Cut and/or coarsely grind to a diameter or width of 1 to 20 mm. This cutting and/or coarsely pulverizing culm is carried out under dry conditions in order to efficiently perform alkali treatment in the next alkali treatment step. The coarsely pulverized raw material passes through a hopper 4 and a vibrating feeder 5 into a total IFIl.
K! An appropriate amount is measured at 6 and conveyed to a solid-liquid countercurrent contact device 8 by a belt conveyor 7. Solid-liquid countercurrent contact device 8
has the functions of alkali treatment and dealkalization treatment,
The coarsely pulverized raw material is treated with an alkali by being continuously contacted with an aqueous solution having a concentration of 1M0L or less at a stage before the solid-liquid countercurrent contact device 8, and then treated with an alkali at a stage after the solid-liquid countercurrent contact device 8. Dealalization treatment is carried out continuously by water washing means. The dealkalized raw material is fed into a pulverizer 10 via a hopper 9 and pulverized under a wet process.

Wet pulverization consumes less power than dry pulverization.

Next, the present invention will be explained in more detail using examples.

Example 1 Rice straw having the composition shown in Table 1 was used as a raw material and pretreated according to the flowchart shown in FIG. At this time, a 0.25M0L NaOH aqueous solution was used as the alkaline solution, and the alkali treatment and dealkalization treatment were performed using a solid-liquid countercurrent contact device at 80° C. for a residence time of 1 hour.

As a result of this alkali treatment, the rice straw composition changed as shown in Table 2. Comparing with Table 1, there is almost no change in the amount of cellulose, whereas total ffi! The change was large, and it became clear that grinding after alkali treatment was more advantageous in terms of grinding energy.

Table 1 Component composition of raw rice straw Cellulose 40 Hemicellulose 25 Lignin 20 Ash 15 Car speed 10
0 Table 2 Component composition of rice straw after alkali treatment Cellulose
38 ・ Hemicellulose 11 Lignin 6 Ash 3 Monkey 5
8 Table 3 shows the effect of pretreatment on the saccharification reaction. For the saccharification reaction, Cellulase Onozuka R-10 was used at 0.
．． 2%, rice straw 1.0%.

The test was conducted at a temperature of 40° C. and a pH of 5.0. Table 3 shows the sugar (glucose) conversion rate 48 hours after the start of the reaction. As shown in Table 3, the process of alkali treatment→fine pulverization showed a superior pretreatment effect compared to the process of pulverization→alkali treatment.

Moreover, as shown in Table 4, it has become clear that the process of alkaline treatment→fine pulverization exhibits a far superior effect even in terms of the power consumption for pulverization per unit weight of the pulverized material.

In addition, when pulverizing after alkali treatment, wet pulverization has been found to be superior to dry pulverization because a drying step is not required and there is no scorching caused by frictional heat generation.

7- Table 3 Pretreatment effect on saccharification reaction Song sugar conversion rate (%) Fine grinding → Alkali treatment 91 Alkali treatment → Fine grinding 86 Coarse grinding only 45 Table 4 Pretreatment effect on grinding power consumption Grinding consumption power ( K Fine pulverization → Alkali treatment 0.24 Alkali treatment - → Fine pulverization 0.04 Example 2 Pretreatment was performed according to the same flow as Example 1. However, the alkali treatment was performed in a batch method in a flask. Treatment temperature 25.40, 80.120℃, treatment time 0.5, 1
．． The test was carried out for 3 hours. As a result of performing saccharification reaction 8- under the same conditions as in Example 1, the saccharide conversion rates after 48 hours were as shown in Table 5.

From Table 5, it is clear that treatment at 100° C. or lower has the same effect as treatment at 120° C., indicating that alkaline treatment under normal pressure is sufficient. That is, not only is the pressure resistance of the alkali treatment equipment no longer necessary, but also the continuous alkali treatment has become easier.

Table 5 Effect of treatment temperature and time on saccharification reaction (4
Sugar conversion rate after 8 hours) Example 3 Pretreatment was performed according to the same flow as in Example 1. However, in order to compare the effects of the alkali treatment equipment, we used a Diffuser roto cell extraction machine as an alkali treatment equipment.
A vertical basket 1-type extractor was used. No significant differences were found in the binding and saccharification reactions.

Example 4 Pretreatment was performed according to the same flow as in Example 1. However, the type and concentration of alkali was changed as shown in Table 6. Differences in pretreatment effects on the saccharification reaction are summarized in Table 6. belongs to.

Table 6 Effect of type of alkali and temperature on saccharification reaction NaOH0,188 NaOHO,2591 NaOH0,593 K O110,189 KO80,2592 KO+-10,592 Na2CO30,185 IVla2GO30,2588 Na2CO30,572 1V la2SO12587 Ca(OH)20 .01 62 to 2 CO30
, 2585 Example 5 Pretreatment was carried out along the same flow as in Example 1 using rice hulls and sugarcane bagasse as raw materials instead of rice straw. Table 7 shows the pretreatment effects on the binding and saccharification reactions. The sugar conversion rate is after 48 hours.

Table 7 Effect of raw materials on saccharification reaction

[Brief explanation of drawings]

FIG. 1 shows (2) Weighing of this invention, and FIG. 2 shows an embodiment of this invention. 1, raw material r1 2, cutter 3, coarse pulverizer 4, hopper 12-5, vibration feeder 6, weighing machine 7, belt conveyor 8, solid-liquid countercurrent contact device 9, hopper 10, fine pulverizer applicant new fuel Representative of Oil Development Technology Research Association Akimine Osu

Claims (1)

[Claims] 1. When saccharifying cellulose raw materials, the raw materials are crushed into pieces with a length of 1 to 100 mm and a width of 1 to 20 mm,
1 weigh of an aqueous solution of an alkali metal or alkaline earth metal hydroxide, sulfide, carbonate, or saline sulfate having a concentration of IMOL or less without heating or humidifying the pulverized raw material f1 under normal pressure. A pretreatment method for cellulose-based raw material II for saccharification, which comprises contacting with an aqueous solution or an aqueous solution of two or more of them to perform alkali treatment, followed by dealkalization treatment, and wet-pulverizing the dealkalized raw material. 2. The pretreatment method according to claim 1, wherein the alkali treatment and dealkalization treatment are performed in a solid-liquid countercurrent contact device. 3. Wet grinding is a colloid mill and refiner. The pretreatment method according to claim 1, which is carried out in a ball mill or rod mill.