JPH0549331B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for transporting a slurry containing at least one aluminum salt selected from the group consisting of satin white slurry, polyaluminum chloride slurry, and sulfuric acid band slurry.

In recent years, as a method of transporting solid particles such as paper clays such as calcium carbonate and Sachin White without the need for human intervention, a method has been used to suspend them in a liquid such as water to form a slurry and transport it through pipes. There is. However, when solid-liquid often separates during transportation or transportation is interrupted, the solid particles may settle immediately because the specific gravity of the solid particles is generally higher than that of the liquid, or depending on the properties of the solid particle surface. Sometimes it settled and solidified, and when we tried to transport it again, it wouldn't flow or the pipes would get clogged.

There has been a desire for an additive that can be uniformly dispersed in a liquid contained in a slurry and at the same time prevent solid particles from settling or caking when the slurry is being transported. A surfactant called Pumpade is known as such an additive, and bentonite is often used, but if the slurry contains divalent cations such as calcium ions or Fe ³⁺ or Al ³⁺ If trivalent cations such as cations are included, they may react with surfactants or bentonite, resulting in a significant decrease in surfactant action or resulting in bentonite with low swelling properties, making it impossible to put it to practical use. I understood.

The present inventors have been researching mountain bark for many years, and found that when this mountain bark is added to a slurry containing at least one kind of aluminum salt selected from the group consisting of sachin white slurry, polyaluminum chloride slurry, and sulfuric acid band slurry, slurry It was discovered that solid-liquid separation during transportation can be completely prevented, and the present invention was completed based on this knowledge.

That is, the present invention provides a method for transporting a slurry, which comprises adding mountain bark to at least one kind of aluminum salt-containing slurry selected from the group consisting of sachin white slurry, polyaluminum chloride slurry, and sulfuric acid band slurry, and transporting the slurry. It is.

The mountain bark used in the present invention is a clay mineral that has many hydroxyl groups on its surface, and contains hydrous magnesium and silicate.
Sepiolite (silicate), hydrated magnesium aluminum silicate (hydrous
Attapulgite (also known as palygorskite) is a mineral derived from magnesium aluminum silicate. It is a general term for minerals commonly known as mountain cork, mountain leather, and mountain wood. Synthetic magnesium trisilicate is also one of these.

The slurry in the present invention refers to a fluid slurry mixture in which fine solid particles are suspended in a liquid, and specifically, slurry is selected from satin white slurry, polyaluminum chloride slurry, and sulfuric acid band slurry. A slurry containing at least one aluminum salt. The sachin white slurry as used in the present invention means a slurry in which fine solid particles suspended in a liquid are mainly sachin white. That is, in the case of Sachin White alone or in addition to Sachin White, clay, calcium carbonate, barium sulfate,
Slurries containing basic lead carbonate, titanium oxide, etc. are included.

The proportion of solid particles in the slurry is approximately 5 to 80
It is about % by weight.

Examples of liquids contained in the slurry include water, aliphatic saturated alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, and butyl alcohol, ethylene glycol, propylene glycol, trimethylene glycol,
Examples include 1,4-butanediol, 1,5-pentanediol, glycols such as polyethylene glycol having a molecular weight of about 400 to 600, polyhydric alcohols such as glycerin, or mixtures thereof.

The slurry may contain particles such as sand, stone, clay, resin, pulp, fibers, and the like.

The amount of mountain bark added to the slurry is about 0.01 to 10% by weight based on the slurry, and about 0.01 to 20% by weight based on the solid content in the slurry.

When adding mountain bark, the solid particles contained in the slurry and mountain bark are mixed in powder form,
A means of adding liquid to this to make a slurry, adding mountain bark powder or paste-like mountain bark to the slurry,
This can be done by uniformly mixing and stirring using a stirrer or screw mixer, or by preparing an aqueous dispersion of mountain bark in advance and mixing it with solid particles to make a slurry.

The paste of mountain bark or aqueous dispersion of mountain bark used in the above-mentioned operation is preferably a dispersion having a mountain bark concentration of about 0.05 to 50% by weight, particularly about 0.01 to 10% by weight. This aqueous dispersion, like other clays, can be obtained by simply placing the mountain bark in water and stirring and mixing by appropriate means. When making this aqueous dispersion, for example, hydrogen peroxide, glycols, etc.
Dispersion can be made easier if a polyhydric alcohol such as glycerin or sugar is applied to the mountain bark in advance. Furthermore, alcohols such as methanol and ethanol, ketones such as acetone, and esters such as ethyl acetate may be added to water in advance. Dispersion of mountain bark can also be promoted by using hot water instead of water. Any dispersion method may be used for the dispersion, but a dispersion having a mountain bark concentration of about 1% by weight or less can be dispersed, for example, using a high-speed mixer. For highly concentrated dispersions or pastes,
For example, a method such as a three-roll method can be used. For dispersions of 1 to 5% by weight, a dispersion method in which stirring and kneading are carried out simultaneously, such as using a paper clay dispersion machine, is preferred. When obtaining a paste-like mountain bark, a well-dispersed aqueous mountain bark dispersion may be prepared in advance at a low concentration, and this may be concentrated using a filter press, an Oliver filter, or the like.

In the present invention, dispersion aids such as sodium polyphosphate, sodium polymethacrylate, polyethylene glycol, sodium dodecylbenzenesulfonate, metal salts of fatty acids, surfactants, or lubricants are added to the slurry containing mountain bark. may be added.

The method of the present invention is an extremely useful method industrially because no phenomena such as solid-liquid separation or cake formation are observed during slurry transportation.

Next, the present invention will be specifically explained with reference to Examples. In the examples, parts indicate parts by weight.

Example 1 Sachin White is CaO−Al ₂ O ₃ −H ₂ SO ₄ −H ₂
It is a needle-shaped crystal that exists in an equilibrium system of O, and is a coating filler to increase the whiteness of the paper surface, but it must be stored in phase equilibrium, and it is usually
It is sold in paste form at 25% by weight. but,
It is easy to make a cake by clumping it on the bottom, and when adjusting the paper coating composition (clay, satin white, adhesive, dispersant, etc.), the cake must be scraped off with a shovel or trowel. It takes a lot of effort to mix the cake uniformly.

Make Sachin White slurry by uniformly mixing 2 kg of Sachin White, 180 g of paper clay, 20 g of Sepiolite, and 800 g of water.

After standing for a day and night, the slurry did not have a layer of water on top, could be easily stirred with a stirring rod, and could be freely transferred with a sand pump. During the transfer of the slurry, I took 100ml samples several times and measured their solid content, which was 23.3±0.4% by weight.
It was uniform.

Comparative Example 1 Among the slurry formulations of Example 1, those without the addition of mountain bark were uniformly mixed in the same manner as in Example 1 to prepare sachin white slurry without the addition of mountain bark.

If you leave it for a day and night, it will have a layer of transparent water on the top.
A white cake formed at the bottom and was not easily dispersed with a stirrer, and when I used a sand pump to transfer it, at first it only pumped water, and when the cake began to flow out, the pump became clogged and I could not transfer it.

Comparative Example 2 A bentonite-added sachin white slurry is prepared in the same manner as in Example 1, except that bentonite is used instead of mountain bark in Example 1.

After standing for a day and night, the slurry has a layer of water on top, but it has become extremely thick. Although it was possible to stir with a stirring bar, the viscosity was too high to be transferred using a sand pump.

Example 2 Sachin white 1.2Kg, calcium carbonate 800g,
Make Sachin White Slurry by uniformly mixing 180g of titanium oxide, 20g of mountain bark, and 800g of water.

After standing for a day and night, no water layer formed on the top, and it was easy to stir with a stirring rod, and it could be freely transferred with a sand pump. During the transfer, I took 100ml samples several times and measured their solid content, but none of them showed any results.
The content was uniform at 23.3±0.4% by weight.

Claims (1)

[Claims] 1. A method for transporting a slurry, which comprises adding mountain bark to a slurry containing at least one kind of aluminum salt selected from the group consisting of sachin white slurry, polyaluminum chloride slurry, and sulfuric acid band slurry, and transporting the slurry.