JPH04202871A - Production of pulp - Google Patents

Abstract

PURPOSE:To produce pulp having excellent quality with a simple process at a low cost without using digesting process by applying a physical treatment such as pressing to a unicellular algae containing cellulose in the cell membrane. CONSTITUTION:A unicellular algae containing cellulose in the cell membrane (e.g. algae belonging to genus Closterium) is pressed to discharge water, life- sustaining tissue, chlorophyll, etc., from the algal cell and obtain the objective pulp.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing pulp using unicellular algae whose cell membrane contains cellulose as a raw material.

(Conventional technology) Conventionally, wood pulp made from softwoods and hardwoods, and bast fibers such as kozo and mitsumata have been mainly used as pulp raw materials, but recently wood valves have become more popular due to manufacturing costs. It accounts for the majority of that.

When manufacturing wood pulp, mechanical pulp (GP, TMP) and chemical pulp (SP, N5SCP) are used.
.

It is classified as P), but the principle is that it forms part of the wood structure, binds cellulose such as cellulose and hemicellulose, and makes the wood a rigid aggregate. The purpose is to recover cellulose and hemicellulose by mechanically or chemically separating and removing lignin, which is contained in wood in an amount of 20 to 35%.

On the other hand, due to resource constraints and production costs, straw (rice, rice, etc.)
Wheat, steamed barley, etc.) and the squeezed residue of sugar millet, commonly known as bagasse, are used as substitutes for wood pulp, but the lignin content of straw and bagasse is 12 to 1, respectively.
4% and 19 to 21%, which is lower than that of wood, but pulp is actually produced by the same pulping operation as wood. Additionally, delignification processes using microorganisms such as biopulving for wood are currently under research and development, but they are still at the development stage.

As mentioned above, it is no exaggeration to say that most of the energy in pulp production is spent on removing lignin. On the other hand, a method for producing cellulose acetate using acetic acid bacteria (Japanese Patent Laid-Open No. 61-212
No. 295) was developed and used for special purposes such as speaker cones.

Similarly, a special purpose paper material that does not contain lignin is sodium alginate paper, which is made from giant kelp (
It has been reported that speaker cone paper is made by extracting alginic acid, a polysaccharide, from seaweeds such as Algae and wood pulp (Kabagi Times, February 1968, Nagahiro Kobayashi). In addition, as a method for producing non-wood pulp, there is a method in which algae containing substantially no lignin is used as a raw material, and this is physically or chemically treated to isolate cellulose or hemicellulose as a pulp material source. Can be mentioned.

This method uses algae such as green algae, red algae, and yellow algae such as Subilogilla, Chaetophora, Urothrix, Coralina, and Tribonema as raw materials and chemically processes them to produce pulp (Japanese Unexamined Patent Publication No. 54-38901), A method for producing pulp using a combination of physical treatment and chemical treatment of angiosperms such as Canada algae (Japanese Unexamined Patent Publication No. 1319/1983)
Among freshwater algae, blue-green algae, xanthoflagellates, and green algae, algae with long bodies such as Hibimidoro, Aomidoro, Amymidoro, and Tribonema are used to produce paper-like algae by light irradiation or chemical bleaching. A method of making a sheet alone or mixed with other pulp material sources (Japanese Patent Publication No. 1983-520)
There is.

(Problem to be solved by the invention) In the conventional pulp manufacturing method using wood as a manufacturing raw material,
The amount of pulp that can be obtained from wood is 90% for mechanical pulp and 50% for chemical pulp. Mechanical pulp yield is 90%
However, the energy consumption of mechanically scraping the lignin from the wood is said to be 2400KWh/Ton pulp, making it an energy-intensive valve manufacturing method.
In addition, lignin adheres to and remains in the pulp, and because it is not used to produce high-quality pulp, the market share of mechanical pulp in Japan is 1.
It is slightly less than 0%.

Chemical pulp is of good quality, and as a result of innovations such as using the lignin in the wood as a heat source during pulp production, it is positioned as a valve manufacturing method with good energy consumption, but the pulp yield is low at 50%. That was the problem.

On the other hand, the increase in CO, which is considered the main cause of global warming,
While it has been pointed out that there is a close relationship with the recent increase in fossil fuel consumption, it cannot be denied that deforestation, which serves as a source of CO□ absorption, also plays a role. In particular, deforestation during the logging of useful timber such as lauan and mahogany in the tropical rainforests of Thailand, Malaysia, the Philippines, and other Southeast Asian countries is attracting international attention as an environmental issue.

The paper production volume in Japan is 27 million tons (1989), of which 50% is produced using virgin pulp, which consumes over 40 million tons of wood every year. This means that

This means that on a global scale, wood production reaches 3 billion i/year.
The current forest area of 2.5 billion hectares is decreasing by 20 million hectares every year, and the demand for pulp and wood is increasing by 4,000 hectares every year.
~50 million rrr/year, and there is a possibility that it will be taken up as a global problem, and there has been a desire to use non-wood pulp as a source.

Furthermore, as a non-wood pulp material source, methods using angiosperms such as Canada algae, some green algae, blue-green algae, xanthoflagellate algae, and red algae have been proposed, but these methods From the same perspective as the valve manufacturing method, the raw material algae (angiosperms and other algae) are chemically treated,
Since the pulp refining method is adopted, it destroys the cell membrane that makes up the external structure and contains cellulose, and also processes polysaccharides such as starch and chloroplasts that control carbon dioxide assimilation inside the cell membrane. As a result, increased processing costs,
This caused an increase in energy consumption and a decrease in pulp yield.

In addition, the production of cellulose acetate by acetic acid bacteria and the production of sodium alginate paper extracted from brown algae do not use wood as the starting material, but the fiber length and width are very short compared to conventional fibers, making it suitable for use in special fields. was limited to.

The present invention has been proposed to solve the above-mentioned conventional problems.

(Means for Solving the Problem) Therefore, the present invention uses unicellular algae in which cellulose is contained in the cell membrane (including the cell wall) as a raw material, and physically processes it by squeezing etc. to produce pulp. It is something that comes to life in a way that makes it easier to understand, and it is used as a means to solve problems.

(Function) In securing pulpwood sources, low energy consumption and high valve yield are considered to be effective means economically and in preventing deforestation on a global scale. From this point of view, ■ The lignin content is virtually zero; ■ The cell walls that make up the algae contain cellulose; ■ It is a unicellular algae with a long algal body length, and the algal body length/algal body width ratio is 10. ~100, we search for plants that satisfy the following at the same time, and as a result, C1os
It belongs to the algae of the genus Terium, and by squeezing the algae, life-sustaining tissue mainly composed of water and chlorophyll in the algae flow out from a part of the cell membrane, making pulping possible.

The reason for this is that the cell membranes of these algal bodies contain cellulose and hemicellulose, which are effective as a source of pulp material, and hemicellulose is useful for mediating hydrogen bonds between valves. It's for a reason. On the other hand, direct chemical treatment of these algae causes a decrease in the yield of cellulose and hemicellulose due to destruction of cell membranes containing cellulose and hemicellulose, damage to hemicellulose, and starch inside the cell membrane. As a result, the chloroplasts that are responsible for carbonic acid assimilation and the polyphenol group Ii are also treated, resulting in a negative effect of lowering the pulp yield and increasing the amount of chemicals consumed.

In the present invention, as a result of adopting a pulping method that is compatible with the algae structure, the pulp yield from the algae is improved, and it is also possible to improve the pulp yield from the algae. As a result of the efficient presence of these substances in the bulb, it is possible to increase the bonding force between fibers and improve the strength.

(Example) Examples of the present invention will be described in detail below. According to the present invention, by using algae containing cellulose in its cell membrane, it does not contain lignin, which consumes a lot of energy in the wood valve manufacturing process and is the main cause of reducing pulp yield. , energy consumption and pulp loss used for lignin removal can be reduced to substantially zero.

In the present invention, we selected unicellular algae that contain cellulose in their cell membranes, have a long algal body length, and have a ratio of algal body length/algal body width in the range of 10 to 100. Examples of such algae include C1osteriu+w of the Chlorophyta phylum Crescentophyceae.
acerosum, Closteriumeh
renbergiL Closterium mo
niliferum, C1os-terium gr
acile, Closterium calospo
rum, CI-osterium acjcular
Examples include Closterium incurvum, Closterium incurvum, etc., but they are not limited to these in any way, and any algae that has a long body length (and satisfies the alga body length/alga body width ratio) can be used without artificial treatment.

Each of the above-mentioned algal bodies contains cellulose and hemicellulose in the cell membrane, and inside the cell body there are life-sustaining tissues, water, and assimilated products.

Therefore, by squeezing the algae, the life-sustaining tissue mainly composed of water in the algae and chlorophyll are released from a part of the cell membrane, and the material is pulped and made into paper and wood valves to make paper-like sheets. be able to.

The configuration of the present invention will be explained in detail below using specific examples.

Specific Examples Among the genus Crescent algae, seven types shown in Table 1 were selected for culture experiments.

Ca(NOs) z4Hz02g/j! ,KNO3L
og/l, NNH4N0z5/2, β-Naz
glycerophosphate 3g/l,
MgS0a4Hz02g/l, Vitamin B+
z 0.01a+g/j! , Biotino, 01mg
/ 1, Th1anuire HCI ll1g/j
L FeC1=・68z019.6zg/f, MnC1
z・4Hz03.6zg/l, Zn5Oa・IH
zO2,2u g/f! , CoCIz・6HzOO,
4zg/l, NazMoO4・2Hz00.25
μg/j2, Na, EDT^・2Hz0166μm/
1, Fe(NH4)z(S043z・6Hz0 75μ
g/l, in a medium adjusted to pH 7.2 with 40 g/l of HEPES at 25°C under illumination of 7000 lux.
While ventilating air containing 5% carbon dioxide gas, light and dark 12
Cultures were carried out under time-cycling conditions. In this operation, seven types of algae were cultured sequentially and in batches. Table 1 shows the yield, shape, and size of these seven types.

Table 1 Batch Culture Test Results As a result of this test, algal bodies with a biological shape with a body length/width ratio of 10 to 100 were obtained. The body of the algae contains life-sustaining tissue mainly composed of water and chlorophyll, and due to the compression operation after harvesting the algae, the width of the algae after these internal bodies are drained is It has been observed that the number decreases to about 175/-1710, and if this is taken into account, most types can be usefully used.

Next, 10 g of algae (dry basis) obtained in Step 2 of the specific example was collected into a compressor 1 consisting of a container 2, a container 3, and a metal sintered plate 4 shown in the drawing, and a pressure of 0.2 kg/cd was applied. After compressing the algae, they were washed with water and dried to obtain approximately the same amount (dry basis) as the test algae. Using this algal body, a handmade sheet was prepared according to JIS-P-8209, and a paper quality test was conducted. The results are shown in Table 2 below.

Table 2 (Effects of the Invention) As explained in detail above, the present invention uses algae that are unicellular and have a relatively similar external shape to wood valve fibers, and that have a cell membrane. By using algae containing cellulose as a raw material and physically processing it by pressing etc., it becomes a valve.
We have succeeded in manufacturing a valve that can replace wood valves. It is extremely useful as an alternative resource to cope with the increasing low consumption in response to global warming countermeasures and the decline of forest resources worldwide, and it is a relatively high-grade valve that does not contain lignin. Moreover, since the cooking process in the valve manufacturing process is not required, the process is simple and economically advantageous, and it is also advantageous in terms of pollution, such as no foul-smelling substances generated during the cooking process. It has excellent characteristics such as In addition, the present invention is not only capable of using the valve according to the present invention alone (it is also possible to mix it with a wood valve or a synthetic valve and use it as a raw material for papermaking), and a wide range of fields of application can be expected.

[Brief explanation of the drawing]

The drawing is a sectional view showing an example of a processing device for performing squeezing and the like in the present invention. Explanation of the main parts of the figure 1 - Presser 2.3 - Container 4 - Metal sintered plate 5 - Sintered plate support ring 7 Single weight 8 - Wet algae

Claims (1)

[Claims] A method for producing pulp, which uses unicellular algae whose cell membranes (including cell walls) contain cellulose as a raw material and turns it into pulp by subjecting it to physical treatment such as squeezing.