JPH02298367A - Grinding adjuvant - Google Patents

Abstract

PURPOSE:To obtain a grinding adjuvant enhancing grinding effect in a hydraulic mineral grinding process and preventing flocculation by using the residual liquid obtained after 60wt.% or more of three kinds of ethanolamine obtained by reacting ethylene oxide and ammonia is distilled off. CONSTITUTION:Monoethanolamine, diethanolamine and triethanolamine are obtained by reacting ethylene oxide with ammonia. Subsequently, 60wt.% or more of three kinds of ethanolamines are distilled off and the obtained residual liquid is used to obtain a grinding adjuvant. This grinding adjuvant can be used in a small addition amount and shows sufficient grinding effect. Further, the pack set index thereof is also good. The residual liquid near to waste can be utilized and this grinding adjuvant is inexpensive and useful for the effective utilization of resources. This adjuvant is useful in a grinding process of hydraulic mineral such as Portland cement, shaft furnace slag, alumina cement, fly ash, limestone, gypsum or the like.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention improves the pulverization efficiency in the pulverization process of hydraulic minerals such as Portland cement, blast furnace slag, alumina cement, fly ash, limestone, and gypsum. This invention relates to a grinding aid for preventing agglomeration during transportation and storage of powder.

[Conventional technology]

Traditionally, mineral materials, especially Portland cement clinker-1
When grinding blast furnace slag and the like, grinding aids such as diethylene glycol and triethanolamine are used to increase grinding efficiency.

In the grinding process, it is desirable to reduce the mineral material to the desired particle size as efficiently as possible and at a relatively fast rate.

Generally, crushing mineral material causes the mineral particles to disintegrate, exposing fresh active surfaces. This surface probably has high energy due to the breaking of ionic bonds. The surface force of the pulverized particles is maintained for a certain period of time after pulverization, and if it is not reduced or eliminated, the powder may become compacted or bank cent, resulting in poor flowability.

A pack set is a "powder agglomeration" in which, for example, when powder is stored or transported in bags, the powder particles cause agglomeration and stick to each other due to their surface forces.
means. In the present invention, the ease with which agglomerated powder particles start reflowing is indicated by a relative value called the badge set index j. In such cases, the powder particles often form a solid agglomerate, and this agglomerated powder will not survive unless subjected to a significant mechanical shock that disrupts this state.
It becomes particulate and does not flow.

Recently, various grinding aids have been actively used in the grinding of Portland cement clinker and blast furnace slag. Traditionally, triethanolamine, diethylene glycol,
Aniline, p-toluidine, m-phenylenediamine,
Dimethylaniline, diphenylaniline, 2,4.6-
Dolibromoaniline, N-phenylhydroxyamine,
β-phenethylamine, morpholine, pyridine, piperidine, pyrrole, pyrrolidine, pyrroline, pyridazine,
Known examples include pyrimidine, N-methylmorpholine, dimethylpyridine, dimethylethylvirol, piperazine, pinzole resin, resorcin, lignin sulfonate, and oxycarboxylate.

[Problem to be solved by the invention] However, the grinding aids that have been researched and used in the past have limitations in improving the grinding efficiency, and if the amount of grinding aids used is increased to improve the grinding effect, However, there was a problem in that the grinding cost increased. Therefore, there has been a need for a grinding aid that is more easily available and has significant effects in small amounts.

[Means to solve the problem]

The present inventors have conducted repeated research to solve the above-mentioned problems, and synthesized monoethanolamine, jetanolamine, and triethanolamine by reacting ethylene oxide and ammonia. The present inventors have discovered that components in the residual liquid after distilling off more than % of the mineral content, particularly ethanolamine-based substances with relatively large molecular weights, are effective as grinding aids for mineral materials, and have completed the present invention.

The grinding aid of the present invention is added dropwise or by spraying to the material to be ground before or during the grinding of the mineral material. Further, it is added in an amount of 0.002 to 0.1% by weight, preferably 0.005 to 0.05% by weight, based on the material to be crushed.

[Effect]

Since the active ingredients of the grinding aid of the present invention are the residual liquid after distilling off monoethanolamine, jetanolamine, and triethanolamine, the compound group cannot yet be identified. However, it is thought that it is a composite of an amine compound or a condensate thereof, which has a larger molecular weight than conventional grinding aids. Moreover, it has a high effect of preventing agglomeration of powder, and even though the amount added to the material to be crushed is small, a sufficient pack set index can be obtained, and it is also excellent in economical efficiency.

〔Example〕

Fat 1 Till crushed in a porcelain ball mill with a capacity of 6.81!
2.5 kg of Boltland Cement Talinker and 75 g of gypsum trihydrate were added, and the various grinding aids shown in Table 1 were added at the addition rates shown in Table 1, and the grinding process was carried out for 6 hours. . The obtained samples were divided into "Sample 1" to "F Sample 3" respectively.
And so.

Grinding experiments were conducted in the same manner as in the above examples, except that conventional ethylene glycol and water were used as grinding aids. The obtained samples were designated as "Sample A" and "Sample B."

The samples obtained in the above Examples and Comparative Examples were subjected to a fineness test, a flow test, and a compressive strength test according to JIS-
It was carried out in accordance with the regulations of R5201. Furthermore, the pack cent index was measured and these results are also listed in Table 1.

In addition, the backset index was measured by the following method.

100 g of the powder sample was placed in an Erlenmeyer flask (capacity 250 rnff) mounted on a variable vibrator, and after vibrating it for 15 seconds, the Erlenmeyer flask was removed from the vibrator.
It was gently tilted so that its center (the central axis of the opening) was horizontal and then mounted on the jig. Then, in this state (while keeping the center horizontal), rotate the flask at an angle of 180 degrees around its center at a rate of 100 revolutions per minute, and calculate the number of 180 degree rotations required to collapse the sample inside. It is a backset index. Therefore, the smaller the value of the pack set index is, the easier the powder is to handle with less agglomeration.

From the test results for each sample listed in Table 1, it was found that the grinding aid according to the present invention exhibits better performance in small amounts.

〔Effect of the invention〕

According to the present invention, sufficient pulverization effect can be obtained with a small addition rate, the puncture set index is also good, and the residual liquid is a low-cost substance that is close to conventional waste, so it is extremely useful for effective use of resources. It is an invention.

(Margin below)

Claims (1)

[Claims] A grinding aid consisting of a residual liquid obtained by reacting ethylene oxide and ammonia to synthesize monoethanolamine, diethanolamine, and triethanolamine, and distilling off 60% by weight or more of the three types of ethanolamine produced.