JPS61212400A - Granular composition of paper making sludge adjustable in water resistance - Google Patents

Abstract

PURPOSE:To reduce the carrying and transporting cost of a granular compsn. of paper making sludge which can be adjusted in water resistance and to make possible the continuous treatment of a large amt. by using a self-curing inorg. material and inorg. filler such as kaolin in combination with the paper making sludge thereby producing the above-mentioned compsn. CONSTITUTION:The self-curing inorg. material such as cement is used at <=200pts.wt. by 100pts.wt. solid of the paper making sludge in the stage of treating said sludge and at least one kind of the inorg. fillers such as the oxide, hydroxide, carbonate and sulfonate of alkaline earth metals, kaolin, zeolite, pearlite, diatomaceous earth, bentonite and silica powder are used at <=350pts.wt. in combination therewith. The granular compsn. of the paper making sludge which can be adjusted in water resistance is thereby produced. The carrying and transporting cost is considerably reduced and the continous treatment of a large amt. in a short period is made possible by the above-mentioned method.

Description

Detailed Description of the Invention [Industrial Application Field 1] The present invention uses a self-hardening inorganic substance such as cement and alkaline earth metal oxides and hydroxides in treating raw paper sludge (also referred to as bulpus sludge). The present invention relates to a composition for producing paper sludge granules, ie, granules, which can be adjusted in water resistance and is characterized by the combined use of a carbonate, a carbonate, and a sulfate.

[Prior Art] Papermaking raw sludge, which is the main treatment target of the present invention, is a waste that is generated in large quantities as a secondary product when papermaking companies make paper, and generally contains 70 to 90% water. It is a highly fluid waste that is difficult to dispose of.

The organic content is 70-80% for Western paper and 40-50% for recycled paper.
Most of it consists of hemicellulose and other materials, and an example of waste paper based inorganic content is 5iOz 18-40%,
ANz037~18%, Mg03~6%, Ca01~
4% and 1 to 2% of Fe2O3, but there is generally no problem with heavy metals.Currently, this raw papermaking sludge has a high moisture content, and as a result of papermaking, a large amount is inevitably produced, so papermaking companies are also concerned about heavy metals. The current situation is that no innovative solution has been found to this disposal. In reality, waste is incinerated, landfilled, or pressed into boards for reuse, but all of these methods involve burning. The cost of shipping, transportation, and other costs are high, and the board has many problems with its appearance and strength, so the reality is that it has no choice but to do so.

[Problems to be Solved by the Invention] The present inventor has devised a method that enables mass treatment for the purpose of pollution prevention, including reuse of high water content raw paper sludge produced in large quantities on a daily basis, and at the same time saves freight costs and heat as much as possible. As a result of intensive research in order to save money, reduce costs, meet corporate demands, and enable reuse as much as possible, we found that granular materials (particularly It was discovered that the problem was found in granules (granules), and a technological solution was successfully achieved. Until now, there have been attempts to granulate raw papermaking sludge, but because water resistance has been ignored, the sludge will disintegrate in water again, and there is no use for it.Moreover, it has not been possible to granulate large quantities by machine for a short period of time or continuously. Without much thought, they produced prototypes without any purpose, and then reconsidered their uses.The fact that they were not considered further and fell into disuse recently is a natural consequence of the fact that they were simply trying to make granules without any purpose. Currently, in addition to incineration and landfill disposal, forced dewatering press molding is considered a temporary solution.
It is possible to mechanize press molding, but as mentioned above, when considering the integration, processing, and power costs, it is questionable whether it is commercially viable, and there is also the possibility of unevenness of the product due to variations in raw materials.
The evidence for this is that press molding is rarely seen as a solution, and is rarely seen or heard of these days.

[Means for Solving the Problems] and [Operations] Namely, 1. In treating paper sludge, the present invention uses 200 parts by weight or less of a self-hardening inorganic material such as cement for 100 parts by weight of the solid, This papermaking sludge granular composition is characterized in that at least 350 parts by weight of at least one kind of oxide, water oxide, carbonate, or sulfide of an alkaline earth metal is used in combination.

When solidifying papermaking raw sludge, the present invention is characterized by promoting solidification from both hardening and drying by improving physical properties, rather than relying on evaporation drying length as in the past, with hardening taking priority. I can think of it as something. That is, self-curing inorganic substances,
If necessary, add a curing accelerator to prioritize curing as much as possible, but on the other hand, in order to balance the factor of evaporation drying, the surface area should be made as large as possible, and since it is a granule, the surface area is large and the surface is moderately rough. Although it is sufficiently effective, I think that the alkaline earth metal compound mentioned above also contributes to this evaporative drying in addition to the reasons described below. In terms of physical properties, the process progresses in drying 4 to 3.

I think this is ideal from a processing perspective. As a result, granulation is possible without heat treatment, but in the case of continuous large-scale processing, a small final heat source is sufficient, and the energy-saving effect required can be confidently expected.

Self-hardening inorganic materials include various cements, layered acid clay derivatives (with catalysts), water glass, quicklime, etc., but the most suitable for this purpose is cement, and ordinary Portland cement is sufficient. Solids of papermaking raw sludge 1
00 parts by weight, the amount of cement is 200 parts by weight or less, preferably 10 to 80 parts by weight. If it exceeds 200 parts by weight, the amount of cement i will increase, and the contribution to the effect of the present invention will be small and will be meaningless. As shown in FIG. 1, the layered acid clay derivative is a normal acid clay when Me is aluminum, but in the present invention, this aluminum is replaced with sodium or potassium, and the catalyst is also the same. There are those with the structure phosphoric acid and other Estes formed. This product is 120 parts per part of papermaking raw sludge solids.
It is not more than 15 to 50 parts by weight, preferably 15 to 50 parts by weight. Alkaline earth metal compounds include oxides, hydroxides, carbonates, and sulfates, all of which exhibit effects that meet the purpose of wood, but calcium hydroxides, sulfates, and magnesium carbonates are particularly preferred. may be used alone or in combination. The effects of using these materials include reducing the degree of water dispersion due to high water content, assisting in curing acceleration, improving compatibility with self-curing inorganic substances, and improving wettability with water, and the accompanying wetting friction making it suitable for granulation. Certain things are the main reason for its use. The amount of the alkaline stop metal compound is 350 parts by weight or less, preferably 50 to 250 parts by weight, based on 100 parts by weight of the papermaking sludge solids,
If more than 350 parts by weight is added, not only will it be difficult to adjust the water resistance, but the bulk will only increase, and no significance will be recognized.

When cement is used as a self-hardening inorganic substance, hardening accelerators include water glass, sodium aluminate, potassium carbonate, soda carbonate, water-soluble alkali metal salts such as salt, and alum, which forms cement and ettringite during the hardening process. There are many types of ettringite, such as those made by adding calcium sulfate, alumina, etc. to stone activated by smoking, or those made by adding low sulfuric acid type ettringite double salt containing 14 to 18 molecules of crystal water and calcium sulfate.

Any of these can be used for the purpose of the present invention, but alumite activated by smoking and to which calcium sulfate, alumina, etc. are added is most suitable for the purpose of the present invention, and the amount used should be determined based on the usage. ) It is 0.5 to 30 parts by weight, preferably 3 to 15 parts by weight, per 100 parts by weight. This is because less than 0.5 parts by weight is of no value in accelerating curing, and when it exceeds 30 parts by weight, the increase in the degree of accelerating curing is not necessarily parallel to the amount added. Heat insulation, flame resistance, and sound absorption.

Inorganic filler to further enhance the effects of fertilizers and other fertilizers.

It is also more convenient for the purpose of the present invention to add hollow insulation materials such as perlite and other inorganic or organic fertilizers such as urea. Organic polymer compounds used to improve water retention, air permeability, and other physical properties of granules include water-based latex of synthetic resins and synthetic rubber.

There are aqueous solutions of polyvinyl alcohol, polyacrylic acid, polyacrylamide, hydroxyethyl cellulose, methyl cellulose, etc., but any solution may be used as long as it does not have a negative effect on the effects of the present invention and can improve the physical properties. It is best to add high-performance organic polymer water absorbing agents in powder or liquid form during granulation. When mixing and solidifying carbon, waste carbon, end of carbon, etc. to make granular fuel, it is mainly used in waste carbon, coal, charcoal, coke, etc. , wood powder, etc., but in this case, the amount of the self-hardening inorganic substance and alkaline earth metal compound should be adjusted in relation to the combustion effect and calorific value. In addition, other similar wastes such as cellulose-based materials, wood paper, cotton, other granules, powders, cut materials, etc. that may be mixed with papermaking raw sludge may be used as long as they do not impair the effects of the present invention. Naturally, it should fall within the range of unreleased IJJ.

[Example J Example 1 Fresh paper sludge with a water content of 73% 1000 parts by weight Portland cement 100 parts by weight Ettringite-forming hardening accelerator 6 parts by weight Calcium hydroxide 350 parts by weight Water
More than 200 parts by weight of the composition was thoroughly stirred, and the water content was set at around 54%, and the mixture was heated at 2 m/m.
It is easily granulated by spinning at the end of a sieve, with a diameter of 2 tons.
Spherical granules with uniform s/m were obtained. This was left at room temperature for 5 hours, and 880 parts by weight of complete granules with a moisture content of 10% were obtained.
It was obtained with a yield of 97%. This results in the following:

However, for water resistance, after immersing in water at 20±1℃ for 8 hours to check for swelling or disintegration, after drying at room temperature, compare the particle size and appearance with the untreated material.

Flame resistance is tested with a flame length of 3 cm for 20 seconds to check for combustion, flame generation, presence of smoke, etc. Hold the flame at about 2.5cm within the flame length of 3cm.
Spread 0.5 cm over the sample.

When this granule is passed through a hot plate at 70 to 80℃, 10%
It is possible to create granules of moisture before and after.

Example 2 Water content: 80% papermaking raw sludge 700 parts by weight Water content: 80%
% urine urinary sediment aggregate 300 parts by weight Magnesium carbonate 100 parts by weight Calcium sulfate
When 50 parts by weight of the above composition was homogeneously mixed and rotated and rubbed with a metal plate, granules were easily formed.The mixture was left at room temperature for 6 hours, and then passed over a hot plate at 70 to 80 DEG C. for 2 to 3 seconds.

Average diameter: 15mm (a+ax 4.8a+m,
akin 2.1mm) Approximately spherical granules, moisture content 8
．． 7%, the yield was 86.0%. A water resistance test was conducted and there was almost no change, with a slight swell.

[Effects of the Invention] The advantages of the present invention are (1) Since the granulation process can be performed continuously at the place where raw paper sludge is generated, transportation costs, which account for the most important part of waste treatment costs, are significantly reduced. It can be ignored or can be processed continuously in large quantities. (2) Since granules have a significantly large surface area, both curing and drying can be performed in a short time. (3) The water resistance and physical properties can be adjusted freely by changing the quantity of the self-hardening inorganic material and, as an auxiliary, alkaline earth metal compound, making it versatile in use. Therefore, for example, as a soil fertility enhancer or fertilizer, it is possible to have both slow-acting and quick-acting effects due to moisture and bacteria in the soil, and in this case, inorganic fertilizer chemicals and organic fertilizers can also be used together, and they can also be dumped into landfills. However, since the amount of solution can be minimized, the problems that have been caused by large amounts of moisture can be solved at once. (4) As is clear from the composition, the granules of the present invention are fire-resistant, flame-resistant, and water-resistant, and have a large heat-insulating effect due to the organic matter they contain, and have a rough surface, so it is naturally assumed that they have a sound-absorbing effect. Of particular interest is that the specific gravity of the granules according to the invention is approximately 0.2-0.5, compared to other flame-resistant, fire-resistant, and heat-insulating fillers: 2.6 on bentonite, 2.6 on silica. 1-2.3, asbestos 2.8-2.7
As is clear from the above, the characteristic of low specific gravity is considered to be of great significance as a main ingredient or filler, for example, in reducing the weight of building materials.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the layered structure of the layered acid clay derivative used in the present invention.

Claims (1)

[Scope of Claims] 1) In treating papermaking sludge, 200 parts by weight or less of a self-hardening inorganic substance such as cement is used per 100 parts by weight of the solid, and in this case, 350 parts by weight or less of at least one kind is used. A papermaking sludge granular composition whose water resistance can be adjusted, characterized by the combined use of alkaline earth metal oxides, hydroxides, carbonates, and sulfates. 2) When using cement as a self-hardening inorganic substance,
The composition according to claim 1, which uses a cement hardening accelerator such as a water-soluble alkali metal salt, ettringite produced during cement hardening, or a low sulfate type ettringite double salt to which calcium sulfate is added. 3) The composition according to claim 1, wherein appropriate inorganic and organic substances are added at the time of mixing for heat insulation, heat resistance, flame resistance, sound absorption, fertilizer effect, and other purposes depending on the purpose. 4) The composition according to claim 1, wherein an organic polymer compound is added at the time of mixing in the form of an aqueous solution, powder, or emulsion to improve water retention and other physical properties of the granular material. 5) The composition according to claim 1, wherein combustible substances such as carbon, waste carbon, and charcoal powder are added at the time of mixing for the purpose of fuel use. 6) The composition according to claim 1, which is treated by mixing papermaking sludge with other similar wastes. 7) Claim 1 in which water-soluble cellulose derivatives such as bentonite, carboxymethyl cellulose, and hydroxyethyl cellulose, and water-soluble organic polymer compounds such as polyvinyl alcohol are added to further facilitate granulation.
Compositions as described in Section.