CN1035310C - Method for raising mill efficiency by changing rotational speed - Google Patents

Abstract

The present invention belongs to a milling technical process. The present invention overcomes the disadvantages of traditional methods which use permanent speed to adjust and enhance milling efficiency, and provides a method for enhancing milling efficiency by changing rotational speed. The corresponding relationship of rotating speed ratio and time ratio is used for expressing sectional rotating speed changing regularity. A starting section, a mixing homogenizing section, an impact crushing section, an impact grinding section and a grinding section respectively have the speed ratios of 0.16 to 0.87, 0.67 to 1.10, 0.90 to 1.35, 0.67 to 1.21 and 0.54 to 1.00; time ratios are respectively 0.10 to 0.50%, 0.50 to 8.30%, 8.30 to 21.88%, 14.70% to 29.17% and 50.00 to 67.60%. The scheme can be widely used in the industry of ceramic, porcelain enamel, paper making, metallurgy, chemical industry, ore dressing, etc.

Description

Variable speed improves the method for mill efficiency

The present invention relates to the grinding process technology, specifically, it relates to a kind of bulk or the granular material size degradation is the powder milling process of fine powder.

At present, in the batch (-type) grinding process that is widely used in industry such as pottery, enamel, papermaking, metallurgy, chemical industry and ore dressing,, all raise the efficiency with methods such as the adjustment of constant rotational speed or interpolation grinding aids to the research of mill efficiency.For many years, the many scientific workers of ceramic field, in order to seek the factor that influences mill efficiency, performance of announcement grinding operating condition and grinding machine etc. and the mutual relation of mill efficiency are done a lot of work.Be entitled as in " discussion of wet ball mill optimum speed " literary composition the 21st～28 page of " pottery " second phase in 1992, proposed to improving the effect that abrasive body impacts grinding to material, and improved the working speed of grinding machine.This measure is for working speed grinding machine on the low side, when the single hard material of incipient stage of grinding or grinding or grinding contain the more compound of poor material, can receive certain effect, but improve rotating speed and correspondingly can increase power consumption, and do not fit into the variation of different all kinds of materials of grinding rerum natura and whole cycle grinding environment, the i.e. variation of material particles degree, particle surface performance and slip flowability etc.

The objective of the invention is to fundamentally overcome the weak point in the above-mentioned background technology and propose the method that a kind of variable speed improves mill efficiency.It is according to the variation of grinding environment and by the difference of grinding material rerum natura and the different methods that adopt segmentation to change the working speed of grinding mill barrel that ground prod is required, and replaces traditional constant rotational speed method.Thereby reach and improve mill efficiency, increase output and promptly save power consumption, shorten the purpose of grinding time.

Purpose of the present invention can reach by following measure;

A kind of method that improves the ball mill mill efficiency, it is used for the batch (-type) grinding process based on homogenizing, impact and grinding, it is characterized in that, in the transmission system of grinding machine, the adding slewing range is 1～1: 100 arrangements for speed regulation, and its segmentation variable speed rule rate is:

(1) start section: slowly start, its rotating ratio is 0.16～0.87, and time ratio is 0.10%～0.50%;

(2) mixing, homogenizing zone: low-speed running, its rotating ratio are 0.67～1.10, and time ratio is 0.50%～8.30%;

(3) impact comminution section: run up, its rotating ratio is 0. 0～1.35, and time ratio is 8.30%～21.88%;

(4) impact the ground section of holding concurrently: the middling speed running, its rotating ratio is 0.67～1.21, time ratio is 14.70%～29.17%;

(5) ground section: low-speed running, its rotating ratio are 0.54～1.00, and time ratio is 50.00%～67.60%;

(6) shut down section: shut down at a slow speed.

Invention is gone on the basis of the relation of research variable speed and material properties and variable speed and ground prod granularity and size distribution, proposed according to the grinding environment variation, by the difference of grinding material rerum natura and difference that ground prod is required, take the method for sectional-regulated mill speed, the power that abrasive body is put on the material helps grinding most.The course of work: start back slowly starts cylindrical shell, after transfer low-speed running to, help the dispersion homogenizing of material, working media in the cylindrical shell like this, and can reduce before the homogenizing and the power consumption in the homogenization process and reduce adverse effect electrical network.Adopt after the homogenizing to run up, enter that to impact be main pulverizing section, purpose be to make working media to the work of material in order to impact for leading and strengthen its impulsive force, accelerate grinding rate.Along with the refinement of the most of particle of material, rotating speed gradually reduces, and makes working media have impact concurrently and grind the mode of action of material, is the middling speed running.Later stage is adjusted to low-speed running, even make the mode of action obtain further grinding based on the grinding fine, shuts down discharging after the assay determination at last at a slow speed.So, keep grinding among the whole cycle is in efficient operation all the time.

Because running speed of each section and time distribute, according to the variation characteristic of grinding environment and look the hardness, mill feed size of grinding charge material and to requirement of ground prod etc. and select, of a great variety because of the grinding machine specification again, the rerum natura of material etc. also varies, and the inventor adopts the corresponding relation of rotating ratio and time ratio to express segmentation variable speed rule.Rotating ratio (q) is meant the working speed rev/min (r/m) of grinding mill barrel and the ratio of the theoretical critical fire area rotating speed rev/min (r/m) of cylindrical shell; Time ratio (%) be meant each section period and each section period and ratio.

Table 1 is a segmentation speed change rule

Table 1

The inventor will be described in further detail invention in conjunction with following embodiment:

Embodiment 1

One, primary condition

(1) in the transmission system of 1.5 tonnes of batch (-type) ball mill by wet process, adds frequency converter, carry out stepless speed regulation, to realize the grinding machine variable speed;

(2) actual charge is 1.3 tons;

(3) material: ball: water=1: 1.8～2.2: 0.63～0.72;

(4) glazed tile glaze composition is:

Frit 85%～95%,

Kaolin 5%,

Colorant etc. 5%～10%,

(5) material mill feed size≤3 millimeter.

Two,, adopt manually-operated or automatic speed regulation to realize the speed change grinding according to grinding machine working speed in the following form and the corresponding relation of time.

Table 2 is grinding cycle each section running speed and the allocation table of time

Table 2

Three, go through 16～18 hours grinding process, the assay determination glaze slip, 250 orders accumulative total tails over≤and 0.02%.Particle is spherical shape more, and corner angle are slick and sly.

Embodiment 2,3

One, primary condition

(1) 50 feather weight batch (-type) ball mill by wet process;

(2) transmission system adds electromagnetism slippage stepless time adjustment motor, and speed adjustable range is 1～1: 100;

(3) actual charge is 35 kilograms;

(4) glazed tile glaze (A) is embodiment 2, and color glazed brick stock (B) is embodiment 3.The material of embodiment 2,3: ball: water, material basic composition and mill feed size see Table 3.

Table 3

Two,, adopt manually-operated or control realization variable speed grinding automatically according to grinding machine working speed in the following form and the corresponding relation of time.

Table 4 is a glazed tile glaze (A), each section running speed and the allocation table of time when color glazed brick stock (B) is made the grinding object:

Table 4

Three, glazed tile glaze (A) is gone through 16 hours grinding process, the assay determination glaze slip, and 250 orders accumulative total tails over 0.015%～0.006%, and particle is spherical shape more.

Color glazed brick stock (B) is gone through 6 hours grinding process, the assay determination slurry, and 250 orders accumulative total tails over 0.08%～0.017%, and the powder abrasive grain is slick and sly.

The present invention compares with background technology has following good effect:

1, be preceding topic with the every index of ground prod that reaches or super background skill is asked, the constant rotational speed grinding that the present invention is more traditional can be saved power consumption more than 20%, shortens the grinding time more than 20%.

Desired value that the segmentation variable speed method of employing embodiment reaches and the contrast of constant rotational speed grinding desired value see Table 5, as an example explanation.

Table 5

2, the present invention adopts slow startup cylindrical shell, after transfer low-speed running to and can reduce peak point current when starting, reduced adverse effect to electrical network, also help material in the cylindrical shell, the dispersion of working media, homogenizing.

3, can utilize existing grinding machine, transmission system is transformed a little, can realize the solution of the present invention, and available manually-operated, also can control automatically and realize the variable speed grinding, the speed change grinding can be adapted to the grinding operation sequence and the process conditions of existing constant rotational speed, and is easy to use.

Claims (2)

1, a kind of method that improves the ball mill mill efficiency, it is used for the batch (-type) grinding process based on homogenizing, impact and grinding, it is characterized in that, in the transmission system of grinding machine, add the arrangements for speed regulation of slewing range 1～1: 100, its segmentation variable speed rule is:

(1) start section: slowly start, its rotating ratio is 0.16～0.87, and time ratio is 0.10%～0.50%;

(2) mixing, homogenizing zone: low-speed running, its rotating ratio are 0.67～1.10.Time ratio is 0.50%～8.30%;

(3) impact comminution section: high this running, its rotating ratio is 0.90～1.35, time ratio is 8.30%～21.88%;

(4) impact the ground section of holding concurrently: the middling speed running, its rotating ratio is 0.67～1.21, time ratio is 14.70%～29.17%;

(5) ground section: low-speed running, its rotating ratio are 0.54～1.00, and time ratio is 50.00%～67.60%;

(6) shut down section: shut down at a slow speed.

2, variable speed according to claim 1 improves the method for mill efficiency, it is characterized in that the preferred value of each section speed change rule is:

(1) start section: slowly start, its rotating ratio is 0.16～0.80, and time ratio is 0.10%～0.20%;

(2) mixing, homogenizing zone; Low-speed running, its rotating ratio are 0.67～1.00, and time ratio is 0.90%～5.60%;

(3) impact comminution section: run up, its rotating ratio is 0.90～1.20, and time ratio is 9.50%～20.30%;

(4) impact the ground section of holding concurrently: the middling speed running, its rotating ratio is 0.70～1.15, time ratio is 17.60%～25.00%;

(5) ground section: low-speed running, its rotating ratio are 0.55～0.90, and time ratio is 53.13%～66.67%;

(6) shut down section: shut down at a slow speed.