WO2007145484A1

WO2007145484A1 - A processing method for reusing of a wastepaper and a product obtained from thereof

Info

Publication number: WO2007145484A1
Application number: PCT/KR2007/002914
Authority: WO
Inventors: Jong Hwan Lee
Original assignee: Jong Hwan Lee
Priority date: 2006-06-16
Filing date: 2007-06-15
Publication date: 2007-12-21

Abstract

The present invention relates to a method of processing wastepaper for recycling and a product obtained therefrom, and more specifically, to a method for producing a pulp material and a solid fuel recycled from wastepaper.

Description

A PROCESSING METHOD FOR REUSING OF A WASTEPAPER AND A PRODUCT OBTAINED FROM THEREOF

Technical Field

[1] The present invention relates to a method of processing wastepaper for recycling and a product obtained therefrom, and more specifically, to a method for producing a pulp material and a solid fuel recycled from wastepaper.

[2] The present invention can also produce products such as recycled toilet paper, paper, recycled corrugated cardboard and the like by use of said pulp material obtained by the present method. In addition, the present invention relates to a solid fuel obtained by shredding and uniformly mixing coal powder and wooden powder together with said pulp material, molding the resultant mixture in a predetermined size and then drying the resultant molded products. Background Art

[3] In general, wastepaper (newspapers, paper, paper for wrapping products, milk packs) is collected and subjected to recycling processes. The recycling process for producing recycled paper from newspapers comprises mixing the collected newspapers with water and chemicals to dissolve them into small fiber particles, de-inking from said particles, formulating the resultant materials with chemicals in a predetermined ratio, subjecting the resultant formulation to paper making and then cutting the resultant paper in accordance with a standard size.

[4] In comparison with the newspapers to be recycled as above, toilet paper and tissue paper have problems in light of recycling since they are smeared with foreign substances in the course of dumping and are easily dissolved in water, which makes the removal of said foreign substances and the recycling process difficult to be conducted.

[5] Such difficulties in recycling of toilet paper and tissue paper give rise to consistent consumption of wood as a raw material for them. In particular, not only South Korea but also many developed countries are short of forest resources, thereby depending on imported wood for use as paper and tissue paper. Therefore, the purchase of wood leads to a high unit cost and cost of raw materials. Also the use of imported wood brings about damaged forest due to logging, thereby resulting in destroy of an ecosystem.

[6] Moreover, dumped toilet paper and tissue paper are bulky in volume and need some expenditure to dispose them after their use and collection. Most of dumped wastepaper is usually incinerated, which also gives rise to another problem, so called atmospheric contamination.

[7] The existing solid fuels have been enormously used in domestic or industrial purpose even though they generate harmful gases during combustion. The representative solid fuels such as coal and bituminous coal have been continuously depleted due to continuing exploitation, which requires alternative solid fuels. Disclosure of Invention

[8] The inventors of the present invention have carried out extensive research to resolve the above-mentioned problems and succeeded in accomplishing the present invention.

[9] An objective of the present invention, therefore, is to provide a method of processing wastepaper for recycling and a product obtained therefrom, and more specifically, to a method for producing a pulp material and a solid fuel recycled from wastepaper.

[10] Another objective of the present invention is to provide products such as recycled toilet paper, paper, recycled corrugated cardboard and the like by use of said pulp material obtained by the present method.

[11] A further objective of the present invention is to provide a solid fuel obtained by shredding and uniformly mixing coal powder and wooden powder together with said pulp material, molding the resultant mixture in a predetermined size and then drying the resultant molded products.

[12] A further objective of the present invention is to provide a solid fuel for using as an energy source in replace of coal and thus for recycling of wastepaper, which comprises shredding and uniformly mixing 30 to 35% by weight of said recycled material obtained by the present method, 40 to 60% by weight of coal powder and 5 to 10% by weight of wood powder, molding the resultant mixture in a predetermined shape and then drying the resultant molded products.

[13] A further objective of the present invention is to provide a method for improving the incineration of solid fuel and minimizing the harmfulness of gases generated from the incineration of said solid fuel through minimizing the amount of the bleaching agent contained in the solid fuel by repeatedly carrying out the steps of introducing water into said recycled material, stirring and washing the resultant material and then dehydrating.

[14] Such an objective can be accomplished by a method for producing a pulp material recycled from wastepaper, which is characterized by comprising the steps of:

[15] (Sl) a step of bleaching wastepaper consisting of preparing collected wastepaper, introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, stirring the resultant mixture, and then soaking the wastepaper for a predetermined time; [16] (S2) a step of removing foreign substances wherein the bleached wastepaper as in the above step is subjected to a mesh to remove the foreign substances which are not capable of being passed through the mesh;

[17] (S3) a step of dehydrating for removing water from said wastepaper from which foreign substances are removed;

[18] (S4) a step of washing and dehydrating in multiple numbers wherein water is reintroduced into the dehydrated wastepaper, which is stirred, washed and then dehydrated again; and

[19] (S5) a step of molding said wastepaper to give a pulp material having a predetermined shape of lump.

[20] A still further objective of the present invention is accomplished by a method for producing a recycled material obtained by recycling of wastepaper, which is characterized by comprising the steps of:

[21] (Sl) a step of bleaching wastepaper consisting of preparing collected wastepaper, introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, and then soaking the wastepaper for a predetermined time;

[22] (S2) a step of removing foreign substances wherein the bleached wastepaper as in the above step is subjected to a mesh to remove the foreign substances which are not capable of being passed through the mesh;

[23] (S3) a step of dehydrating for removing water from said wastepaper from which foreign substances are removed;

[24] (S6) a step of mixing consisting of shredding and uniformly mixing 40 to 60% by weight of coal powder and 5 to 10% by weight of wood powder into 30 to 35% by weight of said recycled material obtained by said dehydrating step;

[25] (S7) a step of molding the resultant mixture in a shape of predetermined size; and

[26] (S8) a step of drying the resultant molded products.

[27] A still further objective of the present invention is to provide a method for producing a solid fuel recycled from wastepaper, which is characterized by comprising (S4) a further step of washing and dehydrating in multiple numbers following said dehydrating step (S3) wherein water is re-introduced into the dehydrated wastepaper, which is stirred, washed and then dehydrated again, thereby removing the bleaching agent from wastepaper and rendering the incineration of solid fuel easier.

[28] In the following, the present invention is explained in greater detail.

[29] The present invention relates to a method of processing wastepaper for recycling and a product obtained therefrom, and more specifically, to a method for producing a pulp material and a solid fuel recycled from wastepaper. .

[30] Particularly, the present invention relates to a method for producing a pulp material recycled from wastepaper, comprising the steps of: [31] (S 1 ) a step of bleaching wastepaper consisting of preparing collected wastepaper, introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, stirring the resultant mixture, and then soaking the wastepaper for a predetermined time; (S2) a step of removing foreign substances wherein the bleached wastepaper as in the above step is subjected to a mesh to remove the foreign substances which are not capable of being passed through the mesh; (S3) a step of dehydrating for removing water from said wastepaper from which foreign substances are removed; (S4) a step of washing and dehydrating in multiple numbers to remove the bleaching agent from wastepaper wherein water is re-introduced into the dehydrated wastepaper, which is stirred, washed, and then dehydrated again; and (S5) a step of molding said wastepaper to give a pulp material having a predetermined shape of lump. By use of such pulp material, it is possible to produce recycled toilet paper, paper, recycled cardboard and the like easily.

[32] According to the present invention, there is provided a solid fuel obtainable by a method comprising the steps of: a step of preparing recycled material obtained by removing bleaching agent from wastepaper; (S6) a step of mixing consisting of shredding and uniformly mixing 30 to 35% by weight of said recycled material, 40 to 60% by weight of coal powder and 5 to 10% by weight of wood powder; (S7) a step of molding said resultant mixture in a shape of predetermined size; and (S8) a step of drying the resultant molded products to give a solid fuel. Said solid fuel can be used as an energy source in replace of coal, thereby saving natural resources and protecting environment due to recycling of wastepaper.

[33] As bleaching agents, it is possible to use both oxidative bleaching agents capable of exerting bleaching action by use of oxidizing power and reductive bleaching agents capable of exerting bleaching action by use of reduction power. Preferably, examples of oxidative bleaching agents include oxygen-bleaching agents such as hydrogen peroxide, sodium peroxide, sodium perborate and the like, chlorine-bleaching agents such as sodium hypochlorite, sodium chlorite and the like. Examples of reductive bleaching agents include sulfite gas, sodium hydrogen sulfite, hydrosulfide and the like.

[34] The amount of bleaching agents to be used is dependent upon the condition of contamination of wastepaper or the temperature of the bleaching step. The bleaching agents are normally used in amounts of from 0.0001% to 3% by weight, preferably 0.001% to 1% by weight, more preferably 0.005% to 0.1% by weight, based on the dried weight of wastepaper.

[35] The temperature of bleaching step by use of bleaching agents is not more than 60

C, preferably from 30 to 40 C, more preferably at room temperature.

[36] The time period of bleaching step is dependent upon the degree of contamination of wastepaper, the amount of bleaching agents to be used and the temperature of bleaching step. Conventionally, the time period is from 12 to 48 hours at room temperature. If the amount of bleaching agents increases, the time period of bleaching step decreases, which may, however, cause secondary contamination due to bleaching agents. Therefore, it is preferred that the amount of bleaching agents is minimized and the time period of bleaching step is maintained for a predetermined time. Brief Description of the Drawings

[37] FIG. 1 shows a process flow chart in accordance with the present invention.

[38] FIG. 2 shows a schematic drawing of recycling apparatus for producing recycled materials according to the present invention.

[39] FIG. 3 shows a schematic drawing of an apparatus for the manufacture of solid fuel for producing solid fuel according to the present invention. Best Mode for Carrying Out the Invention

[40] The present invention will now be illustrated in more detail by referring to the drawings attached herewith. However, it will be understood that the present invention is not limited to specific drawings.

[41] In the following, there is provided an explanation on the method for producing a pulp material by referring to FIG.. 1.

[42] As a pre-step according to the present method, in a wastepaper collecting step (SO), toilet paper or tissue paper used in toilet and the like are selectively collected and extruded. For this purpose, it is preferred that the amount of other foreign substances should be minimized.

[43] In a next bleaching step (Sl), said collected wastepaper is introduced into a bleaching solution wherein a bleaching agent is dissolved in water, which is stirred and then soaked for 12 to 48 hours to bleach the wastepaper. In a next foreign substances removing step (S2), the wastepaper bleached by soaking in a bleaching solution is subjected to a mesh to remove the foreign substances other than tissue paper which are not capable of being passed through the mesh. It is preferred that foreign substances floating on the solution are removed at the same time.

[44] In the said bleaching step (Sl), any bleaching agents capable of being used in bleaching of wastepaper for recycling can be used. It is preferred that the ratio of bleaching agent to water is selected from the ratio commonly used for other bleaching agents.

[45] In a dehydrating step (S3), water is removed from said wastepaper which is bleached and from which foreign substances are removed in the above steps. Said wastepaper is preferably dehydrated by use of centrifugal force as in washing machine to the extent that the wastepaper could pass through fiber (textile) structure. [46] In a washing and dehydrating step (S5), the bleaching agent contained in dehydrated wastepaper is washed off. More specifically, water is re-introduced into the dehydrated wastepaper, which is stirred, washed, and then dehydrated in the same manner as in the dehydration step (S3). Such washing and dehydrating step (S5) can be repeated in multiple numbers so that the bleaching agent contained in wastepaper is removed.

[47] Finally, in a molding step (S6), said wastepaper from which bleaching agent is removed and which is dehydrated is molded in a lump shape of predetermined size to obtain a pulp material. By this, the method for producing a pulp material is completed.

[48] The pulp material recycled from wastepaper by the present method has effects in that it reduces the use of wood as a raw material for toilet paper and tissue paper, thereby protecting natural environment. It also reduces cost for treating toilet paper and tissue paper which had been dumped. If one makes toilet paper from said pulp material, the method is characterized by having much more convenient steps as compared with the existing method for producing toilet paper starting with wooden materials.

[49] In a following mixing step (S6), 30 to 35% by weight of said recycled material, 40 to 60% by weight of coal powder and 5 to 10% by weight of wood powder are shredded and uniformly mixed. At this step, said recycled material is shredded to give some moisture (water) contained in the recycled material, which in turn render coal powder and wood powder uniformly mixed. In case that the amount of moisture contained in recycled material is not sufficient, one may add some amount of water as desired. Such addition would not affect the method since the final drying step (S8) ensures sufficient drying of water. In this mixing step (S6), it is important that each material is uniformly mixed and the consistency of the resultant mixture is maintained to the extent of being clumped.

[50] The wood powder used as above is obtained by pulverizing wood with a good igniting property. Examples of wood powder include planer dust and wood powder that is obtained by finely chopping and pulverizing wood, which is thoroughly dried.

[51] In a molding step (S7), a paste formed by mixing said recycled material, coal and wood powder is molded into a lump in a predetermined size. The shape and size of the resultant lump vary in accordance with the place the lump is to be used. Finally, in a drying step (S8), the resultant molded products are dried either by air drying or by blowing hot air or cold air to give a solid fuel so that the resultant fuel can be easily combusted. By this, the method for producing a solid fuel is completed.

[52] The solid fuel obtained by the present method can be manufactured in various sizes in accordance with the place the fuel is to be used and then used as an energy source. For example, it can be put into a heater and combusted to warm the room or be used in thermal power stations to produce electricity. The solid fuel is more readily combusted owing to the presence of recycled material from wastepaper and wood powder, while the amount of coal, which has been used in the existing solid fuel, in the solid fuel decreases 40 to 60%.

[53] Moreover, the recycled material of the present invention ensures the recycle of wastepaper, which has not been recycled up to now (tissue paper, toilet paper), and thus can save cost for disposing the wastepaper. The present invention can also reduces atmospheric contamination in light of the fact that wastepaper has been customary incinerated for the purpose of disposal. In this view, the present invention has an indirect effect on the protection of natural environment.

[54] In addition, FIG.2 and FIG.3 illustrate an apparatus in which each said method is conducted, respectively. First, a recycling apparatus (10) for producing a pulp material is shown in FIG. 2. The recycling apparatus comprises a body (11), of which top is opened in a cylinder shape and which is consisted of an outer vessel (1 Ia) and an inner vessel (1 Ib) having a number of holes or made of mesh. At the lower portion of the body, a stirring blade is arranged. Further, a mesh (13) is arranged at a suitable height inside of the body (11). At the bottom of the body (11), there is formed a drain (14) which is opened and closed by a valve (not shown). At a top portion of the body (11), there is formed a water inlet (15). Said stirring blade (12) and inner vessel (1 Ib) are subjected to the rotary power of each motor (16) and (16 ). By means of said water inlet (15), water is introduced to the apparatus (10).

[55] In said recycling apparatus (10) constructed as above, wastepaper is introduced through the top of the body (10), to which bleaching agents and water are added in a suitable amount and then stirred by rotation of the stirring blade (12) to mix them thoroughly. The wastepaper is bleached for 12 to 48 hours, and then subjected to a mesh (13) to filter foreign substances. Then, the dehydration is conducted by a centrifugal force due to the rotation of the inner vessel (1 Ib). To this, water is introduced again, which is washed through the rotation of stirring blade (12) and then the dehydration is conducted by the rotation of the inner vessel (1 Ib). Such steps can be repeatedly conducted for multiple numbers to remove bleaching agents, thereby obtaining a pulp material. By means of this recycling apparatus (10), wastepaper is capable of being recycled as a pulp material.

[56] The dehydration is conducted by a centrifugal force due to the rotation of the inner vessel (1 Ib). To this, water is introduced again, which is washed through the rotation of stirring blade (12) and then the dehydration is conducted by the rotation of the inner vessel (1 Ib). Such steps can be repeatedly conducted for multiple numbers to remove bleaching agents, thereby obtaining a pulp material.

[57] As shown in FIG. 3, the apparatus (20) for producing a solid fuel comprises a hopper (21), a case (22) and a molding portion (23), which are linked one another successively so that a solid fuel is produced by use of said recycled material. The hopper (21) is equipped with a shredder (21a). Once said recycled material, coal powder and wood powder are introduced through the hopper (21) in a weight ratio as defined above, they are finely shredded while passing through the shredder (21a). The case (22), connected with the hopper, is equipped with a screw (22a), in which said introduced materials are stirred and pasted. At the end of the screw (22a), there is equipped with a mold portion (23), which is consisting of a mold (23b) at the end of said screw (22a) and a cutter (23a) at the top of the mold. The materials stirred by the screw (22a) are filled into a mold (23b) by means of its pushing press. When the mold (23b) is full of said materials, the content of the mold (23b) is cut by a cutter (23a). The resultant solid fuels having a predetermined shape are collected at a place and then dried by air dry or by blowing hot air or cold air by force at an appropriate temperature for combustion, thereby obtaining a solid fuel. By this, the solid fuel is completed.

[58] According to the present invention, it is possible to produce a solid fuel successively by means of said recycle apparatus (10) for producing recycled material and said apparatus (20) for producing a solid fuel. Industrial Applicability

[59] The present invention provides a pulp material in a lump shape by introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, stirring the resultant mixture, soaking the wastepaper for 12 to 48 hours to bleach wastepaper, subjecting the bleached wastepaper to a mesh to remove the foreign substances, dehydrating the wastepaper, re-introducing water into the dehydrated wastepaper, which is stirred, washed and then dehydrated. By use of said pulp material as a raw material for recycled toilet paper, recycled paper, cardboard and the like, the recycling of wastepaper can be made easily. It is also possible from said pulp material to produce recycled products such as recycled toilet paper, recycled paper, recycled cardboard and the like.

[60] The present invention also provides a solid fuel by introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, stirring the resultant mixture, soaking the wastepaper for 12 to 48 hours to bleach wastepaper, subjecting the bleached wastepaper to a mesh to remove the foreign substances, dehydrating the wastepaper to give a recycled material, shredding and uniformly mixing 30 to 35% by weight of said recycled material, 40 to 60% by weight of coal powder and 5 to 10% by weight of wood powder, molding the resultant mixture to a predetermined shape and then drying the molded products. Said solid fuel can be used as an energy source in replace of coal and thus can recycle wastepaper. [61] Said recycled material can improve the incineration of solid fuel and minimize the harmfulness of gases generated from the incineration of said solid fuel through minimizing the amount of the bleaching agent contained in the solid fuel by repeatedly carrying out the steps of introducing water into said recycled material, stirring and washing the resultant material and then dehydrating.

Claims

[1] A method for producing a pulp material recycled from wastepaper, which is characterized by comprising the steps of:

(51) a step of bleaching wastepaper consisting of preparing collected wastepaper, introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, stirring the resultant mixture, and then soaking the wastepaper for a predetermined time;

(52) a step of removing foreign substances wherein the bleached wastepaper as in the above step is subjected to a mesh to remove the foreign substances which are not capable of being passed through the mesh;

(53) a step of dehydrating for removing water from said wastepaper from which foreign substances are removed;

(54) a step of washing and dehydrating in multiple numbers wherein water is reintroduced into the dehydrated wastepaper, which is stirred, washed and then dehydrated again; and

(55) a step of molding said wastepaper to give a pulp material having a predetermined shape of lump.

[2] A method for producing a pulp material recycled from wastepaper according to claim 1, wherein said predetermined time is 12 to 48 hours.

[3] A method for producing a pulp material recycled from wastepaper according to claim 1, wherein said bleaching agent is selected from the group consisting of oxidative bleaching agent, reductive bleaching agent and mixture thereof.

[4] A method for producing a pulp material recycled from wastepaper according to any one of claims 1 to 3, wherein the amount of bleaching agent is 0.0001 to 3 % by weight, based on the dried weight of wastepaper.

[5] A method for producing a recycled material obtained by recycling of wastepaper, which is characterized by comprising the steps of:

(51) a step of bleaching wastepaper consisting of preparing collected wastepaper, introducing the collected wastepaper into a bleaching solution wherein a bleaching agent is diluted in water, and then soaking the wastepaper for a predetermined time;

(56) a step of mixing consisting of shredding and uniformly mixing 40 to 60% by weight of coal powder and 5 to 10% by weight of wood powder into 30 to 35% by weight of said recycled material obtained by the said dehydrating step;

(57) a step of molding the resultant mixture in a shape of predetermined size; and

(58) a step of drying the resultant molded products.

[6] A method for producing a recycled material obtained by recycling of wastepaper according to claim 5, wherein said predetermined time is 12 to 48 hours.

[7] A method for producing a recycled material obtained by recycling of wastepaper according to claim 5, wherein said bleaching agent is selected from the group consisting of oxidative bleaching agent, reductive bleaching agent and mixture thereof.

[8] A method for producing a recycled material obtained by recycling of wastepaper according to any one of claims 5 to 7, wherein the amount of bleaching agent is 0.0001 to 3 % by weight, based on the dried weight of wastepaper.

[9] A method for producing a recycled material obtained by recycling of wastepaper according to claim 5, wherein said washing and dehydrating step (S4) is conducted in multiple numbers to remove the bleaching agent from wastepaper.

[10] A solid fuel recycled from wastepaper obtained by a method according to claim 2 or claim 3.