JP2011038188A - Method for producing waste paper pulp from waste newspaper as raw material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing waste paper pulp from newspaper (waste paper) scraped/recovered from homes and offices as a raw material, wherein a special surfactant and electrolyzed water are added to its deinking (ink-removing) process to improve recovery. <P>SOLUTION: The method for producing waste paper pulp from waste newspaper as a raw material includes a process for cutting waste newspaper into small pieces, adding alkaline electrolyzed water obtained by electrolyzing water containing a trace amount of purified salt, to the small cut waste newspaper, stirring the mixture at a high speed to fiberize the waste newspaper, charging the fibrous waste newspaper in a stirring container, adding a proper amount of a liquid surfactant, gently stirring the mixture, and simultaneously removing inks released on the surface of the solution. The liquid surfactant is preferably a sodium straight chain alkylbenzene sulfonate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing waste paper pulp made from old newspaper.

  Traditionally, newspapers are important printed materials that can convey social events as news. The number of newspapers issued in Japan was approximately 50 million copies / day in 2007, and the amount used as newspaper paper is 3.7 million tons. Per year, about 70 kg / year is consumed per household.

  In recent years, with the aim of environmentally friendly paper based on the resource environment, each paper manufacturer has been developing technology for recycling and reducing the weight of used newspaper. Moreover, newspaper collected by paper collection is about 60-80% newsprint becomes waste paper pulp is blended.

On the other hand, newspapers are becoming lighter, and now it is 43 g / m ² . Waste paper pulp is black low-quality waste paper pulp that does not remove printing ink. It is called deinked pulp (deinked pulp: DIP) as a raw material for paperboard, cardboard, etc. Therefore, it has become a raw material for paper that requires whiteness, such as printing paper and toilet paper.

  In addition, recycled newspaper paper containing ink oil is still used as a raw material for bathroom / facial tissue, napkins and paper towels. For example, as in Patent Document 1.

Japanese National Patent Publication No. 10-506155

  In this way, recycling saves raw wood resources, while reducing the burden of waste collection and processing and reducing power consumption related to manufacturing. Recycling is preferred as a result.

  Accordingly, an object of the present invention is to provide special electrolyzed water or a surfactant in the deinking process in the manufacturing process of used paper pulp made from newspaper (used paper) that is discarded or collected from households or business establishments. The purpose of this method is to obtain a method for producing waste paper pulp using old newspaper as a raw material, whereby white paper with an excellent recovery rate can be obtained.

  As means for solving the problems of the present invention, alkaline electrolyzed water obtained by electrolyzing water to which a small amount of refined salt is added is used in the process of producing waste paper pulp made from old newspaper, In the deinking (deinking) step, a liquid surfactant is added to obtain used paper pulp made from used newspaper.

According to the present invention, in order to stir and disaggregate the broken old newspaper, it is treated with alkaline electrolyzed water obtained by electrolysis using salt, so that the generated sodium is converted into sodium hydroxide and used. The remaining chlorine exhibits an effect as a bleaching agent.
In the first place, the residual color of used paper and the use of wood as a raw material are largely attributed to the presence of lignin or degenerated lignin that causes browning of fibers due to pulping. Since the treatment is performed using the alkaline electrolyzed water obtained by electrolysis using, the strength of the pulp broken into fibers is prevented and the strength is maintained.

  Further, among electrolyzed water, alkaline electrolyzed water and various surfactants were examined. As described above, newspaper paper was particularly treated by coexisting with a liquid surfactant (sodium linear alkylbenzene sulfonate). As a result, the deinking (deinking) of the used paper from the surface of the used paper proceeds efficiently, and the intended white used paper can be obtained.

It is explanatory drawing which shows one Example of this invention. It is process drawing which shows one Example of this invention.

  Hereinafter, a preferred embodiment of the present invention will be described. In the waste paper pulp manufacturing process using old newspaper, the waste paper such as newspaper is fragmented, and a small amount of purified salt is added to the fragmented waste paper. Adding alkaline electrolyzed water obtained by electrolyzing water and stirring / disaggregating; deinking the disaggregating solution; and the liquid used in the stirring / disaggregating step is a liquid surfactant. it is a manufacturing method of old newspapers as a raw material used paper pulp, characterized in that it uses coexisting manner.

  An embodiment of the present invention will be described in detail according to an experiment. A process of cutting old newspaper into pieces by shredding or the like, and a piece of old newspaper (1) into about 20 g [four newspapers] (Corresponding to a length of 54.5 × 81.2 cm) is added, 1 liter of alkaline electrolyzed water (3) is added thereto, and the mixture is stirred at a high speed to make old newspaper into a fiber, and this fiber is formed. The disaggregated solution was transferred to a 5 liter stirring tank (4), 4 ml of a liquid surfactant was added, and then gently stirred, and the ink released on the surface of the solution was prototyped with gauze (vertically・ A step of removing the floating ink by attaching a lager (string) 40 cm wide to the blade type stirring rod (5) and rotating it slowly at a low speed (60 to 70 rotations / minute). While observing the state of dirt A process of replacing and washing the lager repeatedly about 5 times, a process of obtaining deinked (deinked) and disaggregated fibrous waste paper pulp (6), and a process of dehydrating (filtering) this Then, it consists of a step of washing the collected waste paper pulp with water (5 liters x 3 times) and then a step of obtaining dried and deinked waste paper pulp. As a result, 12.2 g of recovered paper (recovered) 60.1%).

  In addition, instead of the alkaline electrolyzed water described above, except that acidic electrolyzed water was used, the operation was performed on exactly the same scale, but the waste paper pulp treated with this acidic electrolyzed water cannot efficiently remove lignin, The waste paper was poor in bleaching, and had an adverse effect such as weakening the strength of the pulp due to the influence of acid. As a whole, the paper pulp was slightly darkened and white paper as white as expected was not obtained.

  Furthermore, in order to increase the whiteness of the used paper pulp obtained by using tap water instead of the electrolyzed water (alkaline water and acidic water) described in [0014] and [0015], a surfactant to be used is used. It is necessary to increase the amount to 2 times (8 milliliters), and a large amount of water must be used for water washing to remove the surfactant used at the same time. outflow of pulp fibers also increases the recovery of the waste paper pulp (20-40%) was reduced.

  As described above, the present invention has examined alkaline electrolyzed water and various surfactants among electrolyzed water. In particular, by treating with coexisting liquid surfactant (sodium linear alkylbenzene sulfonate), newspapers can be used. deinking (deinking) of a waste paper surface involved in proceeds efficiently obtained a white pulp fibers for the purpose.

  Increasing the whiteness can be dealt with by increasing the number of times the ink that has been deinked (deinked) and adhered to the disaggregated pulp fibers is washed with water, but it also caused a decrease in the recovery rate of used paper.

  On the other hand, it is necessary to increase the amount of surfactant to be used (0.0025%) in order to increase the whiteness of waste paper pulp using normal water (tap water). A large amount of water was required for the washing. Moreover, every time the number of water washings increased due to the influence of the remaining acid, the outflow of pulp fibers also increased, and the recovery rate (20-40%) as waste paper pulp decreased.

  From the above, the method for producing waste paper pulp made from the old newspaper of the present application is preferably a method using alkaline electrolyzed water obtained by electrolysis of salt, and is used for toilet paper that does not require high whiteness. it is possible, as a recycle waste paper pulp material, it was developed a treatment method that can be recovered.

  Whether or not the first drainage after the deinking (deinking) treatment can be recycled can be flocculated and separated by adding a cationic polymer flocculant. It can prevent pollution.

  Old newspaper of the present invention to establish a technique of the method for manufacturing used paper pulp as a raw material, by performing, sales, those available industrially.

DESCRIPTION OF SYMBOLS 1 Pieced old newspaper 2 Mixer 3 Alkaline electrolysis water 4 Stirrer tank 5 Feather-type stirrer 6 Waste paper pulp

Claims (2)

  It is a manufacturing process that uses old newspaper as a raw material to obtain waste paper pulp. The old newspaper is cut into small pieces, and an appropriate amount of electrolyzed water is added to these small pieces of old newspaper, followed by high-speed stirring. The fibrous old newspaper and the fibrous old newspaper are put into a stirring vessel, and after adding an appropriate amount of a disaggregation solution that is a liquid surfactant, it is released to the surface of the solution while gently stirring. The electrolyzed water used in the step of removing the ink to be removed and the step of deinking these disaggregation solutions is alkaline electrolyzed water obtained by electrolyzing water to which a small amount of purified salt has been added. A method for producing waste paper pulp from old newspaper.   2. The method for producing waste paper pulp using old newspaper as a raw material according to claim 1, wherein the liquid surfactant is sodium linear alkylbenzene sulfonate.

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