JP2009183893A - Method of treating used paper diaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of treating used paper diaper which enables separating used paper diaper with high efficiency and recycling the constituent materials. <P>SOLUTION: The method uses a continuous washing machine having two or more water washing machine tubs arranged in series and comprises washing used paper diaper while transferring it in order from a former-stage to a latter-stage tub. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for processing used paper diapers.

  Paper diapers are composed of an absorbent material made of pulp and the like, a polymer absorbent material (polymer polymer) that retains moisture absorbed by the absorbent material, and a waterproof material (plastic) that encloses these.

  Conventionally, disposal of disposable paper diapers has been best done by incineration for hygienic reasons. However, since they contain a lot of moisture, a large amount of heat is required for incineration, which wastes energy. Moreover, it is desirable to collect and reuse the constituent material of used paper diapers from the viewpoint of effective use of resources.

As a method for recovering the constituent material, for example, there is a separation and recovery process in which pulp or the like constituting the paper diaper is separated using a chemical, and recovered and reused. In this separation and recovery process, the paper diaper was crushed with a rotating blade or the like as a pre-process, and the subsequent separation and recovery were performed. (Patent Document 1)
However, in this separation and recovery process, when the used paper diaper is thrown into the separation processing apparatus, the amount of charge is not managed, so the amount of charge is not constant. As a result, the entire used disposable diaper cannot be sterilized uniformly.

  Also, conventionally, used paper diapers are often processed in a single batch system in which a plurality of processing steps are performed in one tank, and in a single batch system, one batch of used paper diapers is used until all processes are completed. The batch of used paper diapers cannot be started, so the processing efficiency is poor and a large amount of used paper diapers cannot be processed at one time.

  In addition, the polymer absorbent in used paper diapers that has absorbed moisture increases in weight and also loses its fluidity in the form of a gel, reducing the ability of the processing equipment. The absorbent material needs to be dehydrated (decomposed), and it is generally known that salt is effective for this dehydration. Furthermore, additives such as salt are also used for disinfecting used paper diapers. However, when salt is used, each material after dehydration (after decomposition) has a large amount of residual chlorine, which is disadvantageous for various recycling methods. Recycled pulp and plastic, solid fueled pulp and plastic remain. The quality is deteriorated by chlorine. In particular, solid fuel is unsuitable for fuels such as boilers.

Conventionally, pulp, polymer absorbent, and plastic, which are constituent materials of used paper diapers, are separated and separated in water using the difference in specific gravity. In this precipitation separation method, each material is submerged in water. It is necessary to wait until a precipitate layer is formed, and it takes much time and the separation efficiency is poor. Further, each material cannot be accurately separated only by the difference in specific gravity, for example, a polymer absorbent material remains. It adheres to plastic and pulp and it is difficult to convert them into solid fuel.
JP 2002-273731 A

  SUMMARY OF THE INVENTION Accordingly, the present invention is to provide a processing method for used paper diapers that solves the above-mentioned problems and enables the constituent materials of used paper diapers to be efficiently separated and reused efficiently.

  The invention according to claim 1 is characterized by using a continuous washing machine having a plurality of water washing tubs arranged in series and washing the used paper diapers while sequentially moving the used paper diaper from the preceding water washing tub to the subsequent water washing tub. This is a processing method of used paper diapers.

  Invention of Claim 2 is a processing method of the used paper diaper of Claim 1 which dehydrates the polymer absorbent in the used paper diaper which was washed using lime. .

  The invention according to claim 3 is characterized in that the ratio of the lime to the predetermined amount of used paper diaper put into the washing tub is in the range of 3 wt% to 10 wt%. It is a processing method of used paper diaper described.

  The invention according to claim 4 is characterized in that the used paper diaper is washed in the water-washing tank or is washed to separate the constituent materials. It is a processing method.

  The invention according to claim 5 is the processing method of used paper diapers according to claim 4, wherein the constituent materials having different particle sizes separated in the washing tank are separated by being discharged through a screen. .

  In the invention according to claim 6, the water washing step by the water washing tank includes a pre-washing step for pre-washing the used used paper diaper, a main washing step for main washing the pre-washed used paper diaper, and a main washing The used paper diaper processing method according to claim 1, further comprising a rinsing step of rinsing the used paper diaper.

  The invention according to claim 7 includes a solid fuel conversion step of converting the pulp and plastic in the constituent material which has been dehydrated and dried after being separated in the water washing step into a solid fuel. It is a processing method of the used paper diaper of Claims 1-6.

  According to the invention described in claim 1, by using a continuous washing machine for washing used paper diapers while sequentially moving from the preceding water washing tank to the subsequent water washing tank, the next used is completed until all processes are completed. Unlike a one-batch system in which processing of paper diapers cannot be started, used paper diapers can be continuously charged and processed efficiently.

  Further, in the present invention in which used paper diapers are continuously washed in a plurality of washing tanks, it is significant to manage the input amount of used paper diapers to a predetermined amount. This makes it possible to disinfect used paper diapers uniformly and effectively.

  In addition, if the amount of used disposable diapers is managed according to the processing capacity of the processing system, the processing efficiency of the processing system can be improved, and the absorbent material, polymer absorbent material, waterproof material, etc. can be separated smoothly. it can.

  According to the invention described in claim 2, the same effect as that of the structure of claim 1 can be obtained.

  Also, by dehydrating the polymer absorbent in the used paper diaper that has absorbed moisture with lime, the polymer absorbent is reduced in weight, and the fluidity is restored from the gel state to the original state. , A reduction in processing capacity of the processing system is avoided.

  Different from the method using salt for dehydration, various recycling methods, recycled materials such as pulp and plastic, pulp and plastic as solid fuel, for example, this solid fuel is used as fuel for boilers, etc. Is appropriate.

  In addition, the temperature of the washing tank rises moderately due to the reaction heat when lime reacts with water, the dehydration and decomposition ability of the polymer absorbent with lime, the washing effect of used paper diapers, the separation efficiency of the material, The effect of the disinfectant is promoted.

  Furthermore, the load of the heat source for raising the temperature of each washing tank is reduced, and thus the running cost is reduced accordingly.

  Also, lime is less expensive than salt, and the method of the present invention can be implemented at a lower cost.

  According to the third aspect of the invention, the same effect as that of the second aspect of the invention can be obtained.

  In addition, by defining an appropriate ratio (3 wt% to 10 wt%) of lime with respect to a predetermined input amount of used paper diaper, if the amount of lime is too small, the polymer absorbent material remains in a gel state, and lime If there is too much, the problem which ash will adhere to the isolate | separated raw materials, such as a pulp, and the quality will be prevented is prevented.

  According to invention of Claim 4, the effect equivalent to the structure of Claims 1-3 is acquired.

  Also, because the used diapers are continuously shaken or washed with a continuous washing machine to separate the constituent materials, unlike conventional examples, there is no need to crush the paper diapers with a rotary blade as a pretreatment, This can be done at low cost.

  According to the fifth aspect of the invention, the same effect as that of the fourth aspect of the invention can be obtained.

  Also, because the constituent materials with different particle sizes (pulp, polymer absorbent and plastic, etc.) separated in the washing tank are discharged through the screen and separated, the separation time differs from the conventional example in which they are precipitated and separated in water. In addition to being greatly shortened, each material can be accurately separated. For example, the remaining polymer absorbent is prevented from adhering, and plastic and pulp can be easily converted into a solid fuel.

  According to invention of Claim 6, the effect equivalent to the structure of Claims 1-5 is acquired.

  In addition, since used paper diapers are continuously processed through the pre-washing process, the main washing process and the rinsing process, the processing time is shortened and the processing capacity is increased, and a large amount of used paper diapers can be processed. become.

  In addition, the polymer absorbent material that has absorbed moisture can be almost completely separated by the steps of prewashing, main washing, and rinsing.

  According to invention of Claim 7, the effect equivalent to the structure of Claims 1-6 is acquired.

  Further, as described above, in the method of the present invention in which no salt is used, the chlorine content remaining in the material separated and recycled from the used paper diaper is extremely small.

  In addition, plastic has a high calorie as high as heavy oil A. If it is made into a solid fuel, its utility value is high. In addition, the polymer absorbent that has absorbed moisture is separated by the washing process described above, so that it can be easily converted into a solid fuel. is there.

  An embodiment of the present invention will be described with reference to FIG.

  FIG. 1 is a process diagram of a used paper diaper recycling system (used paper diaper processing method).

  This recycling system includes a continuous washing machine 101, a dehydrator 103, and a dryer 105. The continuous washing machine 101 includes one prewash tank, eight main wash tanks, two A basic rinsing bath is provided. Further, these pre-washing tank, main washing tank and rinsing washing tank can perform respective washing steps at two kinds of rotation speeds and two kinds of swing angles.

  In addition, as described above, a paper diaper is composed of an absorbent material that absorbs excrement, a polymer absorbent material that retains its moisture, and a waterproof material and a surface material that wrap them, and the absorbent material is cotton. The polymer absorbent material is a polymer polymer, the waterproof material is composed of a nonwoven fabric such as polyethylene film, polyethylene laminate, polyurethane laminate, and the surface material is polyolefin-based or polypropylene-based. It is made of a nonwoven fabric made of a material such as polyethylene or polyester.

  In addition, it is desirable that the recycled used disposable diaper material contains a large amount of combustible matter and has a large calorific value in order to make it into a solid fuel. In the case of a solid fuel, in order to obtain a large calorific value, the more carbon, the better the less chlorine that generates dioxins or corrodes the equipment, and the less the sulfur released into the atmosphere.

(Description of recycling process of used paper diapers)
(A) In the input management step 1, a certain amount (predetermined amount) of used paper diaper is accommodated in a water-soluble container (bag) and input from an input port. In this charging management process 1, for example, a water-soluble container is charged in a cycle of once every 120 seconds, and used paper diapers are continuously processed in this cycle.

  The water washing process is composed of a pre-washing process 2 performed in one pre-washing tank, a main-washing process 3 performed in eight main-washing tanks, and a rinsing process 4 performed in two rinsing tanks. .

  (B) In the pre-washing step 2, the used paper diaper for one container put in the loading management step 1 is pre-washed, and hypochlorous acid is put for primary disinfection. The mouth of the water-soluble container is melted by the pre-washing, and the used paper diaper is washed down and primarily disinfected, and the polymer polymer that has absorbed moisture is separated.

  (C) In the main washing step 3, while the pre-washed used paper diaper is sequentially moved from the main washing tank (water washing tank) to the subsequent stage among the eight main washing tanks, at 80 ° C. or higher, Washing for a total of 10 minutes or more and secondary disinfection are performed, and the polymer that has absorbed moisture is separated.

  (D) In the rinsing step 4, the chlorine content of hypochlorous acid adhering in the pre-washing step 2 and the main washing step 3 is removed from the used paper diaper, and the high-molecular polymer that has absorbed moisture is separated.

  (E) In addition, in the pre-washing step 2, the main washing step 3 and the rinsing step 4, 5% by weight of quick lime (CaO) is charged into each water washing tank with respect to the used paper diaper being processed. Dehydrates (decomposes) a polymer.

  In addition, reaction heat is generated by the quick calcined lime reacting with water.

  (F) Further, in the pre-washing step 2, the main washing step 3 and the rinsing step 4, the used paper diaper is shaken or washed in each water washing tank, and the absorbent material, the polymer polymer, the waterproof material and the surface are washed. Each material is separated into constituent materials.

  (G) Moreover, each water-washing tank of the pre-washing process 2, the main washing process 3, and the rinsing process 4 is a discharge hole in which a screen (screen) having a predetermined mesh (0.3 mm to 0.5 mm) is attached. Each discharge hole discharges and separates the constituent materials separated as described above by the respective meshes of the screen.

  (H) In the dehydration step 5, the dewatering machine 103 removes moisture from the rinsed used paper diaper. In addition, the polymer is separated from the dehydrated water.

  (I) In the drying step 6, after the polymer is separated and removed, moisture is further removed by the dryer 105 from the absorbent material (cotton pulp and absorbent paper), the waterproof material and the surface material (plastic), dry.

  (J) In the recovery / reuse step 7 for pulp and the like, the polymer polymer separated and separated in each of the above steps is recovered and made into a reusable state.

  The dehydration step 5 may not be included in the above steps, and the drying step 6 may be performed immediately after the rinsing step 4.

  Further, a dehydration step 5 may be provided after the pulp recovery / reuse step 7 to recover and recycle the pulp [fibrous], and a drying step (shown by a dotted line) 6 may be provided after the removal step 5. Also good.

  (K) In the solid fuel conversion step 8, the flocculent pulp, the absorbent paper, and the plastic that have been dried in the drying step 6 and dried are used as the solid fuel. In addition, when these materials are compression-molded into solid fuel, frictional heat of 80 ° C. or higher due to compression is generated, and a moisture removal effect and a disinfection effect are obtained. The recovered plastic may be oiled.

  Further, the recovered plastic can be reused as recycled plastic in addition to solid fuel and oil.

  In this recycling system, for example, when 80 kg of used paper diaper is input, this used paper diaper becomes 8 kg, which is 10% of the input amount after the dehydration process, and 6% of the input amount after the drying process. The weight is reduced to about 5kg.

  Further, the chlorine content of the solid fuel is 0.03% or less, and a very good result is obtained.

[Effect of recycling system for used paper diapers]
Unlike the one-batch system, the recycling system configured as described above can efficiently and continuously process used paper diapers by using a continuous washing machine.

  In addition, the present invention in which used paper diapers are continuously washed with water has a great meaning in managing the amount of used paper diaper input to a predetermined amount, and the processing efficiency of the system is improved by managing the amount of input. In addition, the absorbent material, polymer absorbent material, waterproof material, surface material, etc. can be separated smoothly, and it is possible to disinfect used paper diapers uniformly and effectively, while preventing waste of the disinfectant. Become.

  Further, dehydration with quick lime reduces the weight of the polymer absorbent (polymer) and restores the fluidity from the gel state to the original state, thereby avoiding a reduction in processing capacity of the system.

  In addition, since salt is not used to dehydrate the polymer, various recycling methods, recycled pulp and plastic materials, pulp and plastic solid fuel, oiled plastic, etc. Freed from harm, solid fuel is suitable for fuels such as boilers.

  In addition, the reaction heat of quick lime and water promotes the dehydration ability of the polymer polymer by quick lime, the water washing efficiency of used paper diapers, the separation efficiency of each material, the effect of the disinfectant, etc. Furthermore, the load of the heat source for raising the temperature of each washing tank is reduced, and thus the running cost is reduced accordingly.

  In addition, by defining an appropriate ratio (3 wt% to 10%) of quicklime with respect to used paper diapers (predetermined input amount), if the amount of quicklime is too small, the polymer absorbent material remains in a gel state, and quicklime When there is too much, the problem that ash will adhere to the isolate | separated raw material and quality will be prevented is prevented.

  In addition, the used diapers are washed in a continuous water tank or scoured to separate the constituent materials. Unlike conventional examples, there is no need to crush paper diapers with a rotating blade, which is less expensive. it can.

  In addition, since the constituent materials with different particle sizes (pulp, polymer polymer, plastic, etc.) are separated using a screen, the separation time is greatly reduced, unlike the conventional example in which these are precipitated and separated. Can be accurately separated, for example, adhesion of the remaining polymer absorbent is prevented, and plastic and pulp can be easily made into a solid fuel.

  In addition, because the processing time is shortened and the processing capacity is increased by continuously washing the used paper diaper in the pre-washing process, the main washing process and the rinsing process, a large amount of used paper diapers must be processed. Is possible.

  Moreover, the polymer polymer which absorbed the water | moisture content can be isolate | separated almost completely by each process of a prewash, a main wash, and a rinse.

  Further, in the method of the present invention in which no salt is used, the chlorine content remaining on the material separated and recycled from the used paper diaper is extremely small.

  In addition, since the plastic has a high calorie as high as A heavy oil, it is highly useful as a solid fuel, and the polymer polymer that has absorbed moisture is separated by the water washing step, so that subsequent solid fuel conversion is easy. .

[Other Embodiments Included within the Scope of the Present Invention]
Although the embodiment has been described above, the present invention is not limited to this, and various modifications accompanying the gist of the processing method are possible.

It is process drawing which shows the processing method of the used paper diaper of one Example.

Explanation of symbols

101 Continuous washing machine

Claims (7)

  Disposal of used paper diapers characterized by using a continuous washing machine having a plurality of water washing tubs arranged in series, and sequentially washing the used paper diapers from the preceding water washing tub to the subsequent water washing tub Method.   The method for treating used paper diapers according to claim 1, wherein the polymer absorbent material in the used used paper diapers is dehydrated using lime.   The processing of used paper diapers according to claim 2, wherein a ratio of the lime to a predetermined amount of used paper diapers put into the washing tub is within a range of 3 wt% to 10 wt%. Method.   The used paper diaper processing method according to claim 1, wherein the constituent material is separated by shaking or tapping the used paper diaper in the washing tank.   The processing method of used paper diapers according to claim 4, wherein the constituent materials having different particle sizes separated in the washing tank are separated by being discharged through a screen.   The washing step by the washing tank includes a pre-washing step for pre-washing the used paper diaper that has been charged, a main-washing step for main-washing the pre-washed used paper diaper, and rinsing the used-washed paper diaper. The used paper diaper processing method according to claim 1, further comprising a rinsing step of washing.   The solid fuel conversion process of converting into solid fuel the pulp and the plastic in the said component raw material which were dehydrated and dried after fractionating by the said water-washing process is provided. Of used paper diapers.

Images