JPS6227007B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing spherical sludge formed from fibrous sludge, and more specifically, by adding β-type hemihydrate sludge or soluble anhydrous sludge to the reaction system at a temperature higher than the temperature at which hemihydrate sludge does not become hydrated. The present invention relates to a method for producing a spherical snail. Traditionally, Nisui Setsukou's water slurry is 100 to 150
It is known that an α-type hemihydrate having needle-like crystal fibers can be obtained by heat treatment at
30626). In addition, since the needle-like crystal fibers obtained by this method have a large diameter of 3μ or more, in order to improve this and obtain fine fibers of 2μ or less, yakisekou is hydrated while stirring in water to form fine dihydric fibers. A method has also been developed in which the slurry is made into a slurry in which phlegm is dispersed, and if necessary, dihydrate phlegm is added, followed by stirring and heating under pressure (Japanese Patent Application Laid-open No. 40494-1983). On the other hand, the applicant of the present invention has already succeeded in developing a method for heat-treating snails in an organic acidic medium to carry out a hydrothermal reaction (Japanese Patent Laid-Open No. 109295/1983). However, the above-mentioned conventional methods were not satisfactory in terms of reaction rate or quality of the obtained slag. In particular, the above-mentioned JP-A-52-
Method No. 40494 had drawbacks such as the need to hydrate the roasted rice cake, making the process complicated. The object of the present invention is to solve the above-mentioned drawbacks, to shorten the reaction time, and to provide a new production method that can also produce spherical slag by improving the conventional method that could only produce fibrous slag. That is, in the present invention, raw material sludge consisting of dihydrate sludge, semi-hydrate sludge, or a mixture thereof is made into a slurry in an acidic aqueous solution or an organic solvent-containing aqueous solution, and the slurry is stirred at a temperature of 100 to 170°C to form fibers. To provide a method for producing spherical sludge, which comprises adding β-type hemihydrate sludge or soluble anhydrous sludge at a temperature higher than the temperature at which the semi-hydrated sludge becomes hydrated during the hydrothermal reaction until the spherical sludge is produced. It is something. The raw material used in the present invention is dihydrated, half-hydrated or a mixture thereof. Both α-type and β-type can be used for half-water snails. In addition, as these raw materials,
Naturally produced materials, chemically synthesized materials, or by-products during desulfurization of crude oil or the like may be used. Next, the solvent that can be used in the present invention is an acidic aqueous solution or an organic solvent-containing aqueous solution. The acid component used in the acidic aqueous solution may be either an organic acid or anhydrous acid; for example, organic acids include acetic acid, tartaric acid, formic acid, malic acid, etc., and inorganic acids include sulfuric acid, nitric acid, boric acid, etc. The acid component concentration in this acidic aqueous solution is not particularly limited, but is usually 0.1 to 20% by weight. On the other hand, as the organic solvent in the organic solvent-containing aqueous solution, water-soluble ones such as ethylene glycol, diethylene glycol, and glycerin are used. The content of organic solvent here varies depending on various conditions, but generally water
The amount of organic solvent is 0.1 to 20 parts by weight per 100 parts by weight. When an acid component or an organic solvent is added to water in this way, the solubility of the snail is reduced, and the precipitation of the snail is facilitated in the process described below. In the method of the present invention, the raw material is first added to the above solvent and stirred to form a slurry. The proportion of raw material to be added may be determined as appropriate depending on the type of solvent used, but should generally be kept at 2/3 or less, preferably 1/4 or less, of the weight of the solvent. Further, this slurry is stirred at a temperature of 100 to 170°C to perform a hydrothermal reaction. In the method of the present invention, β-type hemihydrate or soluble anhydrous slag is added to the reaction system during the above-mentioned operation at a temperature higher than the temperature at which hemihydrate slag becomes hydrated. The β-type hemihydrate or soluble anhydrous can be added at any time as long as the temperature of the reaction system is above the temperature at which the hemihydrate is no longer hydrated. For example, by adding the raw material to the above-mentioned solvent to prepare a slurry, This may be added after heating with stirring, or may be added together with the raw material into a solvent that has been heated to a predetermined temperature in advance. In place of the β-type semi-hydrated settsukou added here, α
When using a semi-hydrated mold, fibrous grains are formed, but spherical grains are hardly formed. Anhydrous needle-like crystal fibers can also be used as the soluble anhydrous fiber. In this case, the acicular crystal fibers can also be used as a ground product. The amount of these sludge added is usually 0.2 to 50 parts by weight, preferably 1 to 20 parts by weight, based on 100 parts by weight of the raw sludge. In the method of the present invention, after the above-mentioned addition, a hydrothermal reaction is carried out under heating at 100 to 170°C, preferably 110 to 140°C while stirring. Note that the temperature of the hydrothermal reaction is
At temperatures below 100°C, the rate of formation of spherical snails is extremely slow, or they do not form at all. On the other hand, if the temperature exceeds 170°C, spherical particles will not be obtained and will become powdery. Further, it is necessary to carry out this hydrothermal reaction until spherical shells made of fibers are produced. If the product obtained by the above hydrothermal reaction is subjected to solid-liquid separation if necessary and then dried at about 60°C, a spherical slag formed from α-type hemihydrous fibrous sludge can be obtained. If this semi-hydrated clay is heated and dried at about 200°C, it will become a mold anhydrous clay, and if it is further fired at 500 to 800°C, it will become a mold anhydrous clay. All of these are spherical shells formed by intertwining fibrous materials. As described above, according to the method of the present invention, β-type hemihydrate etc. are added to the reaction system at a temperature higher than the temperature at which hemihydrate is no longer hydrated, and this partially acts like a seed crystal, so that fibrous crystals are formed. reaction time is shortened. Furthermore, the fibrous material forming the obtained spherical fibers has a small diameter and an extremely long fiber length. Furthermore, by changing the type of slag to be added, the shape of the sludge obtained can be arbitrarily selected, such as a spherical shape or a mixture of these and fibrous shapes. Moreover, since hydration of these β-type hemihydrate or soluble anhydrous is unnecessary, the high-temperature solvent can be reused, which is economically advantageous. The spherical clay obtained by the method of the present invention can be used as building materials such as panels, insulation materials, core materials, plastic fillers, filter materials, adsorbents, catalysts, etc., and can also be used as soil conditioners, seedling materials, etc. It can also be effectively used in the agricultural field. Next, the method of the present invention will be explained in more detail with reference to Examples. Examples 1 to 7 and Comparative Examples 1 to 3 Into a 300 ml glass autoclave, 210 ml of solvent and a specified amount of dihydric acid was charged as a raw material, and while stirring at 200 rpm, the temperature was raised at a rate of about 6°C/min. The temperature was raised to 90°C, and various types of ashes were added. After raising the temperature to 120°C, a hydrothermal reaction was further carried out for 10 minutes, and the reaction product was filtered while hot and further washed with methanol to obtain a product. The results are shown in the table. Comparative Examples 4 to 7 Comparative Examples 4 to 7 were carried out in accordance with the above-mentioned examples except that dihydrate sludge was used as the raw material and sludge was not added afterwards. The results are shown in the table. Comparative Examples 8 to 9 The procedure was carried out according to the above example except that β-hemihydrate slag was used as a raw material in an amount of 10% by weight of the raw material dihydrate sludge, and was sufficiently hydrated at 25°C for 1 hour, and no sludge was added afterwards. Ta. The results are shown in the table. Examples 8 to 11 A 300 ml glass autoclave was charged with 210 ml of solvent and a specified amount of raw material dihydrate, and while stirring at 200 rpm, the temperature was raised at a rate of about 6°C/min, and the temperature was raised to 110°C by half. Added water droplets. After raising the temperature to 120°C, a hydrothermal reaction was further carried out for 10 minutes, and the reaction product was filtered while hot and further washed with methanol to obtain a product. The results are shown in the table. Examples 12, 13 210 ml of solvent was placed in a 300 ml glass autoclave, and while stirring at 200 rpm, the temperature was raised to 125°C at a rate of about 6°C/min. At this temperature, a specified amount of raw material was added. Prepare half-watered rice at 120℃.
A hydrothermal reaction was carried out for 10 minutes. The reaction product was filtered while hot and further washed with methanol to obtain a product. The results are shown in the table.

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Claims (1)

[Claims] 1. A raw material made of dihydrated slag, half-hydrated sludge, or a mixture thereof is made into a slurry in an acidic aqueous solution or an organic solvent-containing aqueous solution, and stirred at a temperature of 100 to 170°C to form fibers. A method for producing a spherical sludge, which comprises adding β-type hemihydrate sludge or soluble anhydrous sludge at a temperature higher than the temperature at which the hemihydrate sludge ceases to be hydrated during the hydrothermal reaction until the spherical sludge formed in the above process is produced. 2 The amount of β-type hemihydrous slag or soluble anhydrous sludge added is 0.2 parts by weight per 100 parts by weight of raw material sludge.
50 parts by weight. 3. Addition amount of β-type hemihydrate or soluble anhydrous is 1 part by weight per 100 parts by weight of raw material.
20. The method of claim 1, wherein the amount is 20 parts by weight.