JPH0611949B2 - Processing method of oil palm petiole as pulp raw material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial field Palm oil, which is produced in tropical regions and is a raw material for edible oils and detergents, is collected from oil palm fruits. Oil palms are systematically cultivated on a vast area, fruits are collected, and unnecessary petiole parts are cut off every year. This petiole is rarely used at present and is left in the cultivation area. The present invention relates to a method of pretreatment with an alkali so that pulp strength is exhibited when the unused petroleum petiole part is used as a pulp raw material.

Conventional technology The cut-off petiole is left in the cultivation area and is naturally rotted to become an organic fertilizer. There is no active use and there is a research report that it is used as a raw material for pulp (R. Joedodib.
roto; Berita Selulosa / Des. 1982 Vol.
XVIII No. 4p. 95). However, there is no research or patent to treat the petiole part with alkali and use it as a pulp raw material.

Problems to be Solved by the Invention Since the petiole part of the oil palm contains the precursor of oil and fat synthesized in the leaves, when it is cut off in the tropics, it is rotted by microorganisms such as mold and the petiole part turns black. This black-colored material is unsuitable as a pulp raw material, and the whiteness of the pulp made from it is close to black of about 5%, and the pulp strength is extremely weak because the cellulose is partially decomposed. There are two problems in using the petiole part as it is as a pulp raw material.

Means and Actions for Solving Problems The present inventors have earnestly studied the method for removing the oil / fat precursor present in the petiole part in order to use the petiole part as the pulp raw material, and as a result, the following has been revealed. It was revealed that the fat precursors were removed at higher concentrations of alkali (about 20% caustic soda solution) and higher temperatures (up to 180 ° C). Under such conditions, alkali-based peeling reaction of cellulose caused Partial decomposition occurs, and the yield of processed products is extremely low. The concentration of caustic soda is 8% under the conditions where the oil and fat precursors are removed to the extent that they do not hinder the next pulping and the partial decomposition of cellulose hardly occurs.
It was revealed that the temperature was 100 ° C. or less and the treatment time was 40 minutes or less. Under these conditions, it was clarified that the removal of the fat precursor was preferentially promoted over the partial decomposition of cellulose.

If the oil and fat precursor contained in petiole is extracted and removed with warm caustic soda solution, and the petiole decreases in volume and becomes alkaline with pH of about 11 if it is directly or slightly washed with water and dried, mold and other molds rot. Bacteria do not propagate. The unrotted petiole thus treated can be easily made into pulp chips, and the chips are suitable as a pulp raw material for kraft pulp (KP), thermomechanical pulp (TMP) and the like.

On the other hand, excluding the petiole leaves that have been cut off and immediately dried with hot air contains the oil precursor, but does not rot in a short period of time. However, a large amount of alkali is required when the kraft pulp is digested with this product, a large amount of alkali is required, and the produced pulp contains a blackish brown substance due to the fat precursor, and the pulp has a whiteness of 20% or less. In the case of producing thermomechanical pulp, the fiber slips in the longitudinal direction due to the contained oil / fat precursor, and the cutting of the fiber is prioritized over the unraveling of the fiber. Becomes

On the other hand, when the kraft pulp is cooked from the petiole chips from which the oil and fat precursors have been removed by the alkali treatment method of the present invention, the amount of alkali required is the same as in ordinary kraft pulp cooking, and the whiteness of the produced pulp is 20. % Or more.

Further, when producing thermomechanical pulp from chips of petiole part from which oil precursors have been removed by the alkali treatment method of the present invention, it is possible to defibrate with an appropriate disc clearance, and the strength of the resulting thermomechanical pulp is that of hardwood kraft pulp. Equivalent to. In that case, the pulp yield is about 71%, which is 1.5 times that of kraft pulp, which is very useful. Ie 7
It is of great significance that a pulp equivalent to hardwood kraft pulp can be produced with a yield of about 1%.

The details will be described below with reference to specific examples.

Example 1 The petioles of oil palm were cut off and the leaves were removed, followed by 2-3 divisions and then 3-5.
% Caustic soda solution at 5060 ° C. for 30 minutes, picked, then washed with a small amount of water, 120 ° C.
After drying with hot air, make chips for pulp. The surface pH of the chip was 11.2.

Example 2 Chips made according to Example 1 were treated with active alkali 18
%, Cooking temperature 170 ° C., liquid ratio 1: 5, cooking time 1 hour,
The kraft pulp was cooked under the condition that the sulfidity was 20%. The untreated chips were digested under the same conditions to obtain kraft pulp. Table 1 shows the difference in quality between the two.

Example 3 The chips produced according to Example 1 were first defibrated in water vapor at 120 ° C. and 1.5 atmospheres under the condition of a disk clearance of 0.35 mm, and then a disk clearance of 0.35 mm.
The secondary defibration was carried out in steam of 100 ° C. under the conditions. Untreated chips were subjected to the same primary defibration and secondary defibration with a disk clearance of 0.35 mm. Table 2 shows the difference in the quality of the produced pulp.

Example 4 The chip prepared according to Example 1 was previously immersed in an alkaline aqueous solution to remove excess liquid, and 2% Na in the chip.
It should contain OH. The thus-prepared chips containing alkali were subjected to primary defibration in water vapor at 120 ° C. and 1.5 atm under conditions of disk clearance 0.35 mm, and then secondary defibration under conditions of disk clearance 0.35 mm. The untreated chips were also subjected to the alkaline dipping treatment, primary defibration and secondary defibration in the same manner as the treated chips. Table 3 shows the quality of the produced pulp.

Example 5 Instead of the aqueous alkaline solution used in Example 4, an immersion treatment was performed in an aqueous solution containing both an alkali and sodium sulfite, and 2% alkali (NaOH) and 1% sodium sulfite (Na ₂ SO ₃ ) were added to the chips. In the same manner as in Example 4, the treatments including were applied to the chips prepared in Example 1 and untreated chips to carry out primary fibrillation and secondary fibrillation. Table 4 shows the quality of the obtained pulp.

EFFECTS OF THE INVENTION The effects of the present invention are that, even when pulped as a raw material of the kraft pulp of Table 1 in Example 2, the treated pulp has a high yield and the pulp quality is good.

The most remarkable effect is the alkali-added TMP shown in Example 4.
Is the case. That is, the treated chips are added with alkali T
When MP is applied, the pulp yield is 70.9%, the breaking length is 4.2km, the folding endurance is 68 times and the strength is similar to KP, and the energy required for TMP conversion is 0.55kg. / Kg-low value for pulp. Similar effects are exhibited in the fifth embodiment.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshio Kobayashi 2-3-3 Hananomiya-cho, Takamatsu-shi, Kagawa Shikoku Institute of Industrial Technology (72) Inventor Takayoshi Matsuo 2-3-3 Hananomiya-cho, Takamatsu-shi, Kagawa No. Shikoku Institute of Industrial Technology (56) Reference JP-A-55-62288 (JP, A)

Claims (1)

[Claims] 1. An oil palm (oil palm) petiole leaf cut off from the root of a petiole is cut and removed, and the concentration and temperature of alkali are such that the fibers in the petiole are not soaked, that is, 3 to 8.
% Caustic soda solution in the range of 20 ° C. to 100 ° C. for 20 minutes to 40 minutes, then, as it is or immersed in water for about 10 minutes, and then taken out and dried.