CN107451731A

CN107451731A - The quick method for determining cement ball mill ceramic grinding body optimum gradation

Info

Publication number: CN107451731A
Application number: CN201710637460.9A
Authority: CN
Inventors: 张晓峰; 钱有贵; 李慧冬; 薛鲁阳; 张亮; 姬文勇; 白永刚; 郝巧趁; 孙青�; 陈磊章
Original assignee: Cheng'an Jinyu In India Cements Ltd
Current assignee: Cheng'an Jinyu In India Cements Ltd
Priority date: 2017-07-31
Filing date: 2017-07-31
Publication date: 2017-12-08
Anticipated expiration: 2037-07-31
Also published as: CN107451731B

Abstract

The present invention relates to a kind of quick method for determining cement ball mill ceramic grinding body optimum gradation, comprise the following steps：(1) cement grinding system is demarcated before using ceramic grinding body；(2) measure is by the relative grindability of grinding material；(3) mill feed material of small mill experiment is selected：(4) ceramic grinding body grading distribution scheme is designed；(5) small milling mill test operation；(6) big mill yield is calculated with small mill result of the test；(7) judgement of grading distribution scheme feasibility；(8) ceramic grinding body operational version is adjusted according to process capability；(9) two storehouse grinding body gradations of big mill are calculated according to small mill grinding body gradation.The method of the present invention can quickly determine to grind grinding body gradation preferred plan greatly.

Description

The quick method for determining cement ball mill ceramic grinding body optimum gradation

Technical field

The invention belongs to manufacture of cement grinding field, is related to cement grinding system technique calibration technique, material grindability is surveyed Fixed, cement fineness and distribution of particles determination techniques, mathematical statistics method for optimizing technical ability.Specifically, the present invention relates to a kind of fast The method that speed determines cement ball mill ceramic grinding body optimum gradation.

Background technology

At present, manufacture of cement grinding pow consumption accounts for the 60%~70% of whole energy consumption in production process in cement industry.In cement Under the situation that production capacity surplus market competition is growing more intense, save grinding energy, reduce cost as cement production enterprise raising competitiveness There is an urgent need to.Still occupy leading position in cement industry is to use " roll squeezer+the V of its flow as shown in Figure 1 Type powder concentrator+ball mill+high-efficient powder concentrator " Joint grinding system carries out cement grinding.With the development of grinding technology progress, Cement grinding equipment is more and more large-scale, and metal grinding body (steel ball, steel forging) useful load is typically left in 200t wherein in ball mill It is right.Therefore, the power consumption of ball mill grinding system is mainly influenceed by abrasive body deadweight.And grind in abrasive body rational gradation composition (i.e.：Different size abrasive body is arranged in pairs or groups by different proportion), to improving mill output, reducing unit product power consumption and ensureing product Quality (fineness for reaching requirement) plays vital effect.Two storehouses are generally divided into ball mill, wherein a storehouse is corase grind Storehouse, two storehouses are fine grinding storehouse, and broken due to material is completed by roll squeezer, and ball mill mainly plays levigate, therefore abrasive body Size is small and specification between difference it is few, the number of abrasive body is various.Body Gradation Optimization is ground with big mill to test, that is, is poured out Whole abrasive bodies, are sorted, and are reloaded into by design proportion collocation of weighing in mill；Actual production experiment, work is so repeated Measure too greatly, labor intensity is high, and time-consuming very long, this is impossible in actual production.

It is only its half or so, it is possible to significantly because ceramic grinding volume density is more small than metal grinding body Degree reduces the Weight Loaded of abrasive body in mill, possesses the possibility for reducing grinding energy, more and more extensive in the industry so as to cause Concern.But because the application of ceramic grinding body is in the starting stage at initial stage, also failed in industry according to grinding flow, material The difference such as grindability and cement type, sum up the use experience for different concrete conditions；Particular without a kind of simple easy The method that row rapid Optimum grinds grading, after causing many enterprises to use ceramic grinding body, it is impossible to be quickly found out itself suitable spy The preferred plan of point, and midway of having to terminates, and counts out, causes huge waste.

For it is above-mentioned existing the problem of, determine the optimal level of cement ball mill ceramic grinding body the invention provides a kind of quick The method matched somebody with somebody, enter by using small-scale test grinding machine (the indispensable ф 500mm × 500mm code tests ball mill of cement production enterprise) Row grinding body gradation Optimum Experiment, and according to being docked first using ceramic grinding body creation data with big mill, can be quick It is determined that grinding grinding body gradation preferred plan greatly, energy-saving purpose is realized, and alleviates labor intensity, time saving material-saving.

The content of the invention

It is an object of the invention to provide a kind of quick method for determining cement ball mill ceramic grinding body optimum gradation, its Comprise the following steps：

(1) before using ceramic grinding body, i.e.,：During with metal grinding body, cement grinding system is demarcated

The Joint grinding system refers to that material grinding process is made up of two subsystems, one is pregrinding system, In this subsystem, roll squeezer and V-type powder concentrator are by large granular materials attrition crushing into little particle；The second is by ball mill and height The closed-circuit grinding system of powder concentrator composition is imitated, small particles material is ground into fine powder in the subsystem, reaching finish fineness will Ask.

Enough pre- milling capacities are the prerequisites that ball mill uses ceramic grinding body.

In order to using being contrasted before and after ceramic grinding body, and it is the parameter that small mill experiment provides reference, uses it It is preceding to (demarcate) is determined as follows and analyzed during metal grinding body：

A) match ratio of grinding material is determined, determines manufacture of cement kind and its quality requirement；

B) the fineness situation of change of each position material in process is determined, analyzes the pre- milling capacity of roll squeezer system； It is supplied to 45 μm of the material into ball mill to tail over content after roll squeezer extruding (described to tail over a kind of table that content is fineness of materials Show mode, coarse granule content on the sieve of screening materials carrying sieved with different pore size, is expressed as a percentage) 35-45% is should be less than, if Tail over then needs to take measures to improve pre- milling capacity higher than this requirement；

C) grinding system yield (hourly output is referred to as unit-hour output) is demarcated, counts ball mill and other equipment such as respectively The power consumption of roll squeezer, powder concentrator, blower fan and conveying equipment etc., calculate ton cement output power consumption (abbreviation unit power consumption, ball milling Machine and other equipment unit power consumption sum are referred to as comprehensive unit power consumption)；

Wherein due to the Weight Loaded that abrasive body in ball mill is alleviated using ceramic grinding body, simply ball grinder motor drops Low power consumption；Other equipment operating load does not change, so not power saving.Using ceramic grinding body, the latter two are comprehensive to cement The influence for closing unit power consumption is different, is counted so to separate.

(2) measure is by the relative grindability of grinding material

The complexity of material grinding used is one of important referential data of grinding body gradation design：By various desire grindings Material and cement test with normal sand (middle sand), with test mill separate compiling same time and measurement the specific area, each thing The ratio for expecting specific surface area and normal sand specific surface area is referred to as " material relative grindability ", and ratio is bigger to represent material grindability Better；On the contrary then difficult mill.

(3) mill feed material of small mill experiment is selected

Because ceramic grinding body applies in general to two storehouses of grinding machine, small mill carries out the grinding work that experiment is two storehouses of the big mill of simulation Make situation, thus from small mill test materials fineness should with via the material that two storehouses are initially entered after one storehouse grinding of big mill It is close.

In the case of the fineness data for entering two storehouse materials are obtained in step (1), according to each position thing of system calibrating Expect fineness situation, determine small mill experiment materials feeding place.

(4) ceramic grinding body grading distribution scheme designs

Grinding body gradation designs：According to grinding material feature and product fineness requirement, it is determined that abrasive body filling rate in mill (i.e.：Abrasive body volume accounts for the percentage of mill internal volume), the species of abrasive body, such as ball, section, and specification are selected, and really Determine the ratio of different size abrasive body.

Material acts on of both being needed in grinding process：The larger crushing material of granularity is then needed into during little particle More percussion, it is desirable to which abrasive body has enough weight, (can be ground in storehouse and ground with averagely single ball (section) weight of abrasive body The number of mill body gross weight divided by abrasive body) represent；Small particles material is worn into fine powder then needs more abrasive action (abrasive body rolling friction and shear action), now require that abrasive body has enough total surface areas.

The gross area of abrasive body and average single ball (section) are two key factors for determining mill efficiency again.But the two is again Two of contradiction aspects, its smaller number of the constant abrasive body size of gross weight is more, and surface area is also bigger, but single ball again under Drop.And the two keeps higher numerical value to be nearly impossible simultaneously.But according to the difference of grinding material property, the two it Between certainly exist an optimal equalization point, in the method for the invention, pass through small mill experiment and determine the optimal balance Point.

The rule of ceramic grinding body gradation design：

The density of ceramic grinding body is only half of metal grinding body or so, therefore the specification (ball of abrasive body Being represented with diameter, section is represented with diameter × length) bigger than a metal grinding body grade is averagely heavy to make up single abrasive body Deficiency；In order to make up the deficiency of the abrasive body gross area, filling rate need to reach 1.2-1.4 times or former gold of metal grinding body Belong to more than the 60% of abrasive body Weight Loaded.

The step of grinding body gradation conceptual design：

A) conversion relation of gradation design is carried out with the small big mill of mill simulation

Gradation design should be based on big grind, it is first determined the filling rate of abrasive body and the Burden of different size abrasive body Example, described two parameters are identicals for size mill；Dischargeable capacity according to large and small mill calculates abrasive body general assembly respectively The weight of carrying capacity and each specification abrasive body, simulated test is then carried out with the result of calculation of small mill.Calculation formula is as follows：

The total useful load of abrasive body=grinding machine dischargeable capacity × filling rate × abrasive body unit weight (weight of unit volume)

The mass ratio of the total useful load of each specification grinding body weight=abrasive body × each specification abrasive body

B) fixed abrasive body useful load (i.e. filling rate is constant), primarily determines that preferred grinding body gradation

Preferred scheme can be primarily determined that in relation from average single ball weight (or gross area) with mill efficiency, it is therefore desirable to A series of grinding body gradation schemes are designed according to the following steps.

1. each group grading distribution scheme designed should meet claimed below

1) ceramic grinding body filling rate is determined with 1.2-1.4 times of big mill metal grinding body filling rate originally, i.e., it is fixed small The useful load of mill；Described 1.2 times are using the minimum filling rate requirement in the case of ceramic grinding body.

2) 2-4 kinds, referred to as graduation two, four gradings typically can be selected in abrasive body specification；But should be many for spherical grinding body In 3 kinds, to ensure less accumulation porosity.

3) select the averagely single ball of abrasive body to weigh about in the range of 5-12g, suitable weight interval can be determined as the case may be Such as every 1.5g be a test group, design a series of grinding body gradation schemes.

4) under conditions of the averagely single ball weight of setting abrasive body, the grading distribution scheme of design should keep the maximum total face of abrasive body Product.

2. the design method of each group grading distribution scheme

In each preferred embodiment is designed, utilize in " Excel " software that " programming evaluation " computational methods can be with The scheme for meeting above-mentioned requirements quickly is tried to achieve, concrete operations are as follows：

" programming evaluation " computation model is established, it is necessary to set the content of three parts in " Excel " worksheet：

1) Set cell：The abrasive body gross area is set as optimal objective, it is desirable to which it reaches maximum；

2) Changing Cells：The ratio of different size abrasive body is set as Changing Cells, is calculated and asked automatically by software The abrasive body match ratio of (such as average single ball is equal to required value again) is obtained under constraints；

3) constrain：Average single ball of calculating is important to be equal to setting value, and the abrasive body useful load obtained is equal to set-point etc..

3. carrying out small mill experiment respectively to the grading distribution scheme of design, sample specific surface area after grinding is determined；

The averagely single ball weight of abrasive body or the relation of the gross area and mill efficiency are found out with regression analysis in " Excel " software (with grinding material specific surface area height or reach time length used in finish fineness requirement and represents), therefrom primarily determine that preferred Scheme.

C) with the preferred scheme primarily determined that improve the experiment of abrasive body filling rate, chosen and filled according to power savings Rate.

Filling rate is typically no more than 40% to avoid influenceing big mill inner ventilation.

D) suitably adjusted compared with abrasive body specification ratio in the preliminary preferred scheme of high fill-ratio to selected, form several groups The grading distribution scheme that average single ball fluctuates again, tested with small mill, wherein mill efficiency highest is optimal abrasive body Grading distribution scheme；It is also most reasonably to arrange in pairs or groups that the program abrasive body gross area and average single ball, which weigh two parameters, i.e. optimum balance Point.Wherein, as single ball weight changes, there is respective change therewith in the gross area, i.e.,：Single ball weight increase, the gross area reduce； Single ball weight reduces, gross area increase.

(5) small milling mill test operation

A) body weight is respectively ground according to the abrasive body useful load and different size proportion requirement, precise of design, Such as 0.01kg is accurate to, and load test mill；Mill feed material used in each mill should be with a collection of taken material, to ensure to try The comparativity tested.

B) doses for often grinding loading is fixed as 6kg, can be according to the different controls of grindability in 5-10kg.

C) in order to calculate fineness rate of change, each mill will a point some time be sampled, it is general to be spaced 5-10 points Clock, each sampling amount control is in 150-200g.Sampling starting and time general control is terminated in or so 15-40 minutes, can basis Material grindability suitably adjusts.

D) after every group of material grinding, abrasive body and material are poured out in the lump, are sieved with different pore size abrasive body pressing different rule Lattice separate.

E) after being cleaned up in mill with material on abrasive body, lower battery of tests is carried out.

F) material tails over fineness and specific surface area after determining grinding.

(6) big mill yield is calculated with small mill result of the test

According to actual production data, big mill yield is calculated with small mill result of the test, realizes that small mill docks with what is ground greatly.

According to use instead before ceramic grinding body (when i.e. using metal grinding body, hereinafter referred to as " before changing ") with first using pottery The actual production (for the first time using the optimum gradation for not being optimization, hereinafter referred to as " changed rear ") during porcelain abrasive body, and each group are small The specific surface area value of different grinding times, calculates the big mill yield that each design can reach according to the following steps in mill experiment：

A) change rear different abrasive body species and grading before being changed with the small big mill of mill simulation and carry out grinding experiment, calculating is milled to finished product Grinding time used in fineness requirement, with the time difference of the two, calculate ceramic grinding body and often extend 1 minute than metal grinding body To the influence value a of big mill yield.

A=(changes preceding yield W_Q- change rear yield W_H) ÷ (ceramic grinding body grinding time Ti- metal grinding body grinding times Tj)

B) various kinds group certain time interval Δ t is calculated (when selection is up to two grindings before and after specific surface area of finished products M Between, general interval 10 minutes, i.e. time started t1 and end time t2) in specific surface area rate of change Si per minute：

Si=(t1 specific surfaces product value during end time t2 specific surface product value-beginning) ÷ Δs t

C) the time Ti that various kinds group grinding requires specific surface area M needs to finished product is calculated：

Ti=t1+ [(M-t1 specific surfaces product value) ÷ Si]

D) various kinds group grinding time Ti and virgin metal grading grinding time Tj difference Δ Ti is calculated：

Δ Ti=Ti-Tj

E) influence value Δ Wi of the various kinds group relative to the big mill yield of grinding body gradation before changing is calculated：

Δ Wi=Δs Ti × a

F) various kinds group is asked to grind yield Wi greatly accordingly：

Wi=W_Q-ΔWi

Reach the grinding time length of product fineness requirement it may determine that the quality of grading distribution scheme, conversion with small mill experiment It could judge whether scheme is feasible into big mill yield.

(7) judgement of grading distribution scheme feasibility

According to before changing, change rear abrasive body useful load and yield, ball grinder motor (hereinafter referred to as ball milling motor) and other set The parameters such as standby power consumption, the judgement of grading distribution scheme feasibility can be carried out.

A) derivation of formula is judged：

The synthesis power consumption of grinding system is made up of ball milling motor power consumption and other equipment power consumption two parts, system synthesis before changing Unit power consumption is shown below：

For ceramic grinding body due to its density half about low compared with metal grinding body, it is inevitable that mill efficiency, which reduces, therefore It is also inevitable that yield, which declines,.Above speak of, the loading weight of abrasive body in ball mill is alleviated using ceramic grinding body Amount, simply ball milling motor reduces power consumption；Other equipment operating load does not change, and this part power consumption total amount is basically unchanged.Change System synthesis unit power consumption is then changed into following formula afterwards：

From above-mentioned (1) (2) relational expression, the effect for reducing power consumption could be realized when (2) formula is less than (1) formula.

If it is a to change the electromechanical consumption of forecourt electric mill, other equipment power consumption is b, and yield is c before changing, using ball after ceramic grinding body It is m that electric mill machine, which saves power consumption, and yield reduction amount is n, makes formula (2)≤(1), obtains inequality (3).

Derive to obtain formula (4)：

WhereinTo change the inverse of preceding comprehensive unit power consumption.

Ball milling motor reduced when saving power consumption m only with ceramic grinding body than original metal grinding body weight number it is relevant； And reflect and then determined using the yield reduction amount n of yield height after ceramic grinding body by the quality of grinding body gradation.

From relational expression (4), when yield reduction amount is more than or equal to comprehensive unit before ball milling motor is saved power consumption and changed During the ratio of power consumption, grinding system can not realize the effect of economize on electricity, then grading distribution scheme is infeasible.

B) to the calculating of gradation design scheme power savings

With before the changing of above-mentioned offer, change rear creation data, design synthesis unit power consumption is calculated, with virgin metal abrasive body When be compared.Calculation procedure is as follows：

①

2. design ball milling motor power consumption=virgin metal abrasive body ball milling motor power consumption-design ball milling motor Amount of electricity saving

3. design ball milling motor unit power consumption=design ball milling motor power consumption ÷ designs calculate big mill Yield

4. other equipment unit power consumption=virgin metal abrasive body other equipment power consumption ÷ designs calculate big mill yield

5. design integrates unit power consumption=design ball milling motor unit power consumption+other equipment unit power consumption

6. unit power consumption-design synthesis is integrated during design synthesis unit power consumption reduction amount=virgin metal abrasive body Unit power consumption

7. the economic benefit economized on electricity every year can be calculated according to cement grinding mill annual production and electricity price.

By ball milling motor power saving amount that gradation design scheme calculates, before changing compared to yield reduction amount substitution formula (4), you can Judge the feasibility of design.

(8) ceramic grinding body operational version is adjusted according to process capability

Material grindability and pre- milling capacity the two key factors are must take into consideration using ceramic grinding body.Such as it is both straight Footpath 4.2m ball mill configuration roll squeezer has the differences such as 1800 × 1600mm of ф, 1600 × 1400mm of ф, 1400 × 1200mm of ф Specification, its installed power differ greatly, and pre- milling capacity is different, this be process inherently ability the problem of.

When the warehouse receipt of grinding machine two is pure can not meet economize on electricity target call using ceramic grinding body, it can increase by a storehouse metal and grind Mill body useful load, or even the storehouse length of proper extension one (accordingly shortening in two storehouses), increase more abrasive bodies.Purpose is material Grind thinner, mitigate two storehouse grinding burdens, this is also to put forward one of effective measures of production.

After above-mentioned measure is taken, when still can not meet to require, then ceramic grinding body and metal grinding body are taken in two storehouses Load in mixture.Two warehouse receipts are pure not to reach power savings using ceramic grinding body, be typically due to fineness of materials into two storehouses it is relatively thick or Grindability is poor, it is therefore desirable to more impulsive force.Weight identical metal grinding body (body bigger than ceramic grinding body percussion The small person's impulsive force of product is big), the deficiency of ceramic grinding body impact capacity can be made up by being incorporated a certain amount of metal grinding body.Also by Volume density difference is ground in two kinds, movement locus is also different, and two kinds of movement locus intersect, and is more beneficial for strengthening grinding cutting work With.Take ceramic grinding body to be loaded in mixture with metal grinding body, be to further improve the mill efficiency in two storehouses.

Abrasive body loads in mixture small mill experiment and scheme optimization is carried out according to the following steps：

A) selection of ceramic grinding body specification

Strengthen due to adding metal grinding body rear impact, the less ceramic grinding body of two kinds of specifications should be selected to protect Demonstrate,prove the gross area of abrasive body.

B) selection of metal grinding body species and specification

With reference to the preferable scheme tested entirely with ceramic grinding body, the total useful load of abrasive body is selected, is separately added into equivalent metal Ball or metal segments carry out grinding experiment, and the species of metal grinding body is determined with the high person of specific surface area rate of change.Then from single Ball weight and the metal grinding body of two kinds of specifications similar in larger ceramic grinding body, then grinding comparison is carried out respectively, selected metal is ground The specification of mill body.

C) additional proportion of two kinds of abrasive bodies and total useful load are determined

The effect of two kinds of abrasive bodies when loading in mixture：Ceramic grinding volume density small size is advantageous to increase greatly total face of abrasive body Product；Metal grinding volume density large volume is small to be advantageous to strengthen percussion.The Optimum Experiment purpose loaded in mixture is to seek abrasive body The optimal balance point of abrasive action and percussion.But due to the difference of density, two kinds of abrasive body additional proportion changes, can also Cause the change of total filling rate；Therefore there is also one with total filling rate for the ratio (weight ratio or volume ratio) of two kinds of abrasive bodies Optimal equalization point.

The additional proportion (ceramic grinding body ratio accordingly diminishes) of metal grinding body is stepped up during experiment, and is gradually increased Useful load (filling rate is consequently increased) is added up, designs a series of small mill testing programs.To small result of the test of grinding with step (6) Method extrapolate big mill yield, and carry out regression analysis (utilize Excel software for calculation), drafting graph of relation, find out most Good metal grinding body additional proportion and total useful load, as optimal grading distribution scheme.

Grading distribution scheme feasibility is judged with the method for step (7) and performance analysis, select optimum gradation scheme.

(9) two storehouse grinding body gradations of big mill are calculated according to small mill grinding body gradation

A) filling rate of ceramic grinding body and metal grinding body in small mill is obtained respectively

Abrasive body filling rate=[(abrasive body useful load/abrasive body unit weight)/small mill volume] × 100

B) volume shared by ceramic grinding body and metal grinding body in two storehouses of big mill is obtained respectively

Volume shared by abrasive body=big mill two storehouse dischargeable capacitys × abrasive body filling rate/100 in big mill

C) ceramic grinding body and metal grinding body Weight Loaded in two storehouses of big mill are obtained respectively

Volume × abrasive body unit weight shared by abrasive body in abrasive body Weight Loaded=big mill

D) respective Weight Loaded is obtained according to the ratio of different size abrasive body, draws big barreling mill body grading distribution scheme.

Equally big mill grinding body gradation can be calculated into small mill grading in aforementioned manners, to use small mill verification experimental verification level The quality matched somebody with somebody.

The method of the present invention is adapted in the double closed circuit of " roll squeezer+V-type powder concentrator+ball mill+high-efficient powder concentrator " composition It is used to obtain optimal grinding body gradation scheme in the case of closing two storehouses of grinding system.

The beneficial effects of the method for the present invention is：The difference of the two, which is ground, for size provides small mill and the big mill side of docking Method, accomplish quantitatively to instruct big mill practice；Derive that the economize on electricity of ball milling main frame is dropped with yield using after ceramic grinding body The mathematical modeling of relation between low, it can be determined that the different embodiment party that the intrinsic process capability of grinding system and determination should be taken Case, avoid enterprise from blindly following the wind and start and cause the risk of failure；With mathematical statistics technology, such as programming evaluation, recurrence point The methods of analysis, carries out preferably, obtaining optimal grinding body gradation scheme to small mill result of the test, improves mill efficiency and economize on electricity is imitated Fruit.

Brief description of the drawings

Fig. 1 is that " roll squeezer+V-type powder concentrator+ball mill+high-efficient powder concentrator " Joint grinding system flow is shown in the prior art It is intended to.

Fig. 2 is the relation the time required to being milled to finished product using the ceramic grinding body gross area and material in the embodiment of the present invention 1.

Fig. 3 is the time required to being milled to finished product with material using the averagely single ball weight of ceramic grinding body in the embodiment of the present invention 1 Relation.

Fig. 4 be when being loaded in mixture in the embodiment of the present invention 1 metal grinding body weight than the relation with grinding material specific surface area.

Fig. 5 be when being loaded in mixture in the embodiment of the present invention 1 metal grinding body weight than the relation with mill output.

Fig. 6 is the relation of the abrasive body gross area and mill output when being loaded in mixture in the embodiment of the present invention 1.

Fig. 7 is " programming evaluation " dialog box schematic diagram during the step 4.2 (b) of the embodiment of the present invention 1 " programming evaluation " is set.

Embodiment

Embodiment 1

Below with certain company " roll squeezer+V-type powder concentrator+ф 4.2m × 13m ball mills+high-efficient powder concentrator " cement grinding system Exemplified by system carries out ceramic grinding body Optimum Experiment (see Fig. 1), illustrate implementing procedure.

1 before ceramic grinding body to cement grinding system using demarcating

A) grinding system equipment overview

The grinding system performance of main equipment of table 1

B) cement type and material proportion

The cement type of table 2 and material proportion

Small mill experiment will be with specific surface area 330m²/ kg requires to reach product quality.

C) grinding process fineness of materials situation of change

The process fineness of materials situation of change of table 3

Note：①D50、X₀The aperture size that 50%, 63.2% material is sieved by certain is represented respectively, and it is whole that it characterizes powder material Body fineness, its value is higher, and powder is thicker.

2. distribution of particles, by laser particle analysis-e/or determining, its content is percentage by volume；Tail over as weight percentage, It is so different with 80 μm of granule content numerical value are greater than.

The change of different-grain diameter inventory in the process of table 4

From table 3,4, roll squeezer disposes the 70% coarse granule material for being more than 80 μm, and 3-32 μm of particle in product Leading material 50% by roll squeezer output；Illustrate that the pre- milling capacity of the system is stronger.45 μm of material for entering ball mill tails over (42.1%) it is less than 45%, possesses the condition using ceramic grinding body.

D) yield and grinding pow consumption

The grinding system yield of table 5 and power consumption

Note：Two storehouse abrasive bodies use the metal segments of two kinds of specifications, and ф 10 × 10mm sections account for 75%, ф, 12 × 12mm sections 25%.

2 measure are by the grindability of grinding material

The material of table 6 is with respect to grindability measurement result

Material	Grinding time/min	Density/(g/cm³)	Specific surface area/(m²/kg)	With respect to grindability
					Lime stone	30	2.71	663	1.87
Clinker	30	3.16	330	0.93
					Flyash	30	2.33	499	1.41
Slag	30	2.90	291	0.82
					Normal sand	30	2.64	355

Note：The ratio of each material specific surface area and normal sand specific surface area is referred to as " material relative grindability ", and ratio is bigger Represent material grindability better；It is on the contrary then poor.

As shown in Table 2, the main clinker grinding of the system and slag, it is the material of more difficult mill.

3 choose small mill experiment mill feed material

As seen from Table 3, D50 (meso-position radius), the X of powder concentrator coarse powder are gone out₀(characteristic diameter) and enter two storehouses material very close to saying It is bright the two overall fineness it is essentially identical, therefore choose this material as it is small mill experiment mill feed material.

4 ceramic grinding body gradation designs are tested with small mill

(1) selection of abrasive body specification and the determination of useful load

This example is former from tetra- kinds of diameter ф 13mm, ф 15mm, ф 17mm, ф 20mm size ceramic balls, substitution grinding machine two storehouse Come 10 × 10mm of ф, ф 12 × 12mm steel sections.Useful load 90t suggests in ceramic grinding body producer, filling rate 34.8%, approaches 1.2 times of metal grinding body.

A) to the multistage collocation of different size abrasive body accumulate the measurement of porosity first, measurement result (being shown in Table 7) can Know, the porosity of graduation two is larger, reduces the chance hit between abrasive body, it is thus determined that taking four gradings or graduation three.

Influence of the abrasive body specification of the table 7 collocation quantity to accumulation porosity

B) small barreling mill body useful load

The small total useful load of barreling mill body=small mill dischargeable capacity × filling rate × abrasive body unit weight

=0.0982 × 34.8/100 × 2.2 × 1000=75.16 (kg)

(2) grinding body gradation scheme is quickly designed with " programming evaluation " method

" programming evaluation " computation model is established in " Excel " worksheet

A) " Excel " worksheet design grinding body gradation computational chart (such as table 8) is opened.

Table 8 " programming evaluation " method quickly designs grinding body gradation computational chart

The row of worksheet represent that row is represented with digital number with English alphabet, and the lattice in table are referred to as " cell ", its position Represented with " row number+line number ", such as " M11 " cell is the abrasive body gross area value tried to achieve.

1. abrasive body specification, diameter, material density and total useful load are known, insert in corresponding cell；

2. the single area of abrasive body, volume and single quality, insert the formula such as sphere area, sphere volume；

3. the ratio of different size abrasive body is obtained automatically by " programming evaluation "；

4. having total useful load and different size abrasive body ratio, then the useful load, number, total face of each abrasive body can be obtained Product and total ball weight, calculation formula is inputted to corresponding cell.

5. then summation or average value, then obtain the abrasive body gross area and average single ball weight, the interior input of corresponding cell Summation or Mean Value Formulas.

B) " programming evaluation " is set

Point opens " instrument " column of worksheet, chooses " programming evaluation ", " programming evaluation " dialog box (accompanying drawing 7) occurs.

1. Set cell is set：" M11 " cell of table 8 is arranged to Set cell, and selectes " maximum ", The abrasive body gross area for requiring to try to achieve in the case where this imposes a condition is maximum；

2. Changing Cells：Tetra- cells of J5-J8 of table 8 are set as Changing Cells, i.e., obtained by programming evaluation The ratio of four kinds of specification abrasive bodies；

3. " constraint " condition of setting：

Average single ball weight that average single ball of setup algorithm is weighed=given, i.e. " N11=N12 " in table 8；

Total useful load of the total useful load of abrasive body of setup algorithm=given, i.e. " K11=I5 " in table 8

In order to realize the grading of abrasive body 4, tetra- Changing Cellses of setting J5-J8 are greatly or equal to some value (if setting Some cell is then 3 gradings equal to " 0 ").

This example, which refer to theory of high packing fowler (Fuller) grading formula, tries to achieve the ratio of each specification abrasive body and (is shown in Table 10)。

The fowler grading different size abrasive body ratio of table 10

Ceramic Balls specification/mm	Ф13	Ф15	Ф17	Ф20
					Grading ratio/%	24.65	23.06	32.17	20.12

The ball ratios of Ф 13：J5 >=(24.65*0.2)-[(24.65*0.2) * N12 (single ball weight of setting)/100]

The ball ratios of Ф 15：J6≥(23.06*0.2)

The ball ratios of Ф 17：J7≥(32.17*0.2)

The ball ratios of Ф 20：J8 >=(20.12*0.3)+[(20.12*0.3) * N12 (single ball weight of setting)/100]

The change that Ф 20 and the balls of Ф 13 weigh with the single ball of setting is suitably added and subtracted, and is to adapt to the requirement that single ball changes again. If Changing Cells does not set big or equal to one value (setting is big or equal to 0), only there are 2 gradings (other specification ratios 0), to there is also the scheme that almost single-stage is matched somebody with somebody, the abrasive body gross area is big, but porosity is also big.Why fowler is selected The 20% of grading is used as " guaranteeing the minimum " ratioA large amount of tentative calculations were done, do not have adjustment effect very little, then at most make the abrasive body gross area It is greatly lowered.

After 4. computation model is set, known terms are inputted, given average single ball weight values, point are inserted in N12 cells " instrument → programming evaluation → solution (in dialog box) " is hit, then can quickly obtain the grading distribution scheme of requirement.

(3) the averagely single ball weight (or gross area) of grinding body gradation and the relation of mill efficiency are inquired into

The averagely single ball of selected abrasive body is weighed about in the range of 5-12g, is a test group every 1.5g, is designed a series of abrasive bodies Grading distribution scheme, carry out small mill experiment.Result of the test is shown in Table 11.

The small mill result of the test of grading distribution scheme of the different abrasive body list ball weights (gross area) of table 11

As seen from Table 11, with the increase of single ball weight or the reduction of the abrasive body gross area, material is by grinding to finished product Time is extending, i.e., mill efficiency is declining；Extraordinary linear relationship between them be present, see accompanying drawing 2 and accompanying drawing 3.Explanation Grinding body gradation design is it should be noted that keep the higher abrasive body gross area.

(4) improve abrasive body filling rate and grading is suitably adjusted

As shown in Table 11, best TC-1 grading distribution schemes, only than using ceramic grinding body output increased 4.74t/h first, The expectation of economize on electricity is not reached much.Therefore need to increase abrasive body useful load, and it is relatively low for the averagely single ball weight of abrasive body, enter Row increases the trial of single ball weight.Because yield with require differ too big, abrasive body filling rate is disposably added to 40% and (exceeded 40% pair of mill ventilation has an impact).Adjusted Option and result of the test are shown in Table 12.

Table 12 increases the small mill experiment of abrasive body useful load and the average single ball weight of increase

Scheme TC-7 is TC-1 abrasive body constant rates, and filling rate brings up to 40% by 34.8%, and big useful load of grinding is from 90t Increase to 103.5t, ball milling motor power saving can reduce, but output increased 7.28t/h.

Scheme TC-9 is that TC-1 increases to 40% on the basis of filling rate 34.8%, but increases ball weight part and use ф entirely 20mm balls, add average single ball weight, and output increased 9.45t/h, is this group tests best scheme.

Scheme TC-8 is to be added two groups of TC-1 and TC-5 abrasive body proportioning to average；Scheme TC-10 is by TC-9 The middle ball ratios of ф 13 reduce 15%, and 10% is added to the balls of ф 17, and 5% is added to the balls of ф 20.The purpose of two groups of adjustment is intended to improve grinding The averagely single ball weight of body, effect are all bad.

From experiment, the toatl proportion of two kinds of small dimension ceramic grinding bodies can not be less than 70% (and based on minimum ball), Ensureing the higher gross area (95000cm²More than) in the case of, the appropriate ratio for increasing the balls of ф 20, improve average single ball Weight, is best scheme.

5 calculate big mill yield with small mill result of the test

Need and use metal grinding body and the support about creation data when using ceramic grinding body first.

First 13 are shown in Table using mill yield and small mill analog reslt greatly before and after ceramic grinding body.

Table 13 uses big mill yield and small mill analog reslt before and after ceramic grinding body first

By taking TC-9 grading distribution schemes as an example, calculate that process is as follows with step of the present invention (6)：

(1) calculate ceramic grinding body and often extend 1 minute influence value a to big mill yield than metal grinding body.

A=(changes preceding yield W_Q- change rear yield W_H)/(ceramic grinding body grinding time T_i- metal grinding body grinding time

T_j)=(210-170)/(42.29-15.41)=1.4880 (t/min)

(2) specific surface area rate of change per minute in certain time interval Δ t (this example chooses 30min-40min) is calculated Si：

=(- 30 minutes specific surface product value of 40 minutes specific surface product value) ÷ 10=(351-322)/10=2.90 (m²/kg.min)

(3) Calculation grinding requires the time Ti of specific surface area M (this example 330) needs to finished product：

Ti=t1+ [(M-t1 specific surfaces product value) ÷ Si]

=30+ [(330-30 minute specific surfaces product value) ÷ S_i]=30+ [(330-322)/2.90]=32.76 (min)

(4) Calculation grinding time T_iWith virgin metal grading grinding time T_jDifference Δ T_i：

ΔT_i=T_i-T_j=32.76-15.41=17.35 (min)

(5) the influence value Δ W of big mill yield during relative to metal grinding body is calculated_i：

ΔW_i=Δ T_i× a=17.35 × 1.488=25.82 (t/h)

(6) corresponding big mill yield W is sought_i：

W_i=W_Q-ΔW_i=210-25.82=184.18 (t/h)

The judgement of 6 ceramic grinding body grading distribution scheme feasibilities

Need to provide and change preceding and have related parameter (being shown in Table 14) using what grinding during ceramic grinding body was run first.

Table 14 has related parameter calculating using grinding operational factor before and after ceramic grinding body and design first

(1) grading distribution scheme feasibility judges

Judged with the judgement formula in step of the present invention (7)

In formula：N-use yield reduction value after ceramic grinding body.

Ceramic grinding body scheme is used first：40≤1100/31.45=34.98 schemes are infeasible

TC-9 designs：25.82 ＜ 888/31.45=28.24 realize economize on electricity, but seldom

(2) TC-9 grading distribution scheme power savings are calculated

①

2. ball milling motor power consumption=virgin metal abrasive body ball milling motor power consumption-design ball milling motor saves electricity

=3200-888=2312 (KWh/h)

3. ball milling motor unit power consumption=design ball milling motor power consumption ÷ designs calculate big mill yield

=2312/184.18=12.55 (KWh/t)

=3405/184.18=18.49 (KWh/t)

5. comprehensive unit power consumption=design ball milling motor unit power consumption+other equipment unit power consumption

=12.55+18.49=31.04 (KWh/t)

6. unit power consumption-design synthesis unit power consumption is integrated during comprehensive unit power consumption reduction amount=virgin metal abrasive body

=31.45-31.04=0.41 (KWh/t)

7. the economic benefit of year economize on electricity

Mill hourly output 184.18t/h, running rate calculate by 80%, produce 129.07 ten thousand tons of cement, economize on electricity 52.92 ten thousand per year KWh, 0.58 yuan/KWh of electricity price, annual 30.69 ten thousand yuan of saving expense.But the expense of reduction is very little, it is possible to by the underproduction (18.1 ten thousand Ton) and reduce profit on sales and offset, therefore consider that load in mixture scheme with metal grinding body (does not have to demonstrate the scheme this example of loading in mixture Take storehouse increase useful load measure), the further effect for improving economize on electricity cost declining.

The Optimum Experiment that 7 ceramic grinding bodies load in mixture with metal grinding body

(1) abrasive body loads in mixture test procedure

A) abrasive body loads in mixture gradation design, should be using the ceramic grinding body of two kinds of minimum gauges as the main body of grading, to protect Card abrasive body has larger total surface area；The ceramic grinding body of original big specification is replaced with metal grinding body.With reference to original complete Experiment is proceeded by with 1.2 times of ceramic grinding body Weight Loaded of metal grinding body filling rate, this example still selects small mill useful load 75.16kg。

B) fixed ceramic grinding body specification and ratio, are incorporated metal ball respectively or metal segments carry out small mill experiment, with selection The species of metal grinding body.Numbering HZ-1 and HZ-2, experiment show that metal segments load in mixture with Ceramic Balls during result of the test is shown in Table 15 Metal ball is substantially better than, it is thus determined that being loaded in mixture using metal segments.

15 two kinds of abrasive bodies of table load in mixture abrasive body specification Selection experiment

C) ratio of different size Ceramic Balls is determined

The species and additional proportion of metal grinding body are constant, and the ratio of conversion ceramic grinding body is tested.By in table 15 Two groups of result of the tests of HZ-3 and HZ-4 can be seen that the high person's yield of ф 13mm ball ratios is higher, determine that ceramic grinding body should be with bead Based on.

D) specification of metal segments is determined

The constant rate of useful load and each abrasive body, carried out respectively with ф 10 × 10mm of 12 × 12mm and ф steel forgings to having a competition Test；Found out by HZ-4 and HZ-5 result of the tests, it is obvious to improve output results using the small steel forgings of 10 × 10mm of ф.

E) total useful load and metal grinding body additional proportion are determined

By above-mentioned grinding body gradation Optimum Experiment, best scheme mill output using ceramic grinding body only than being carried first High 7.47t/h, far can not reach the requirement of economize on electricity.Therefore need to carry out increasing abrasive body useful load, and be stepped up gold Belong to the experiment of abrasive body ratio.Result of the test is shown in Table 16.

Table 16 increases total useful load and metal grinding body ratio test result

Regression analysis is carried out to above-mentioned test data, find metal grinding body additional proportion and grinding sample specific surface area and Calculate that mill output has extraordinary dependency relation (see accompanying drawing 4 and accompanying drawing 5)；But not linear relation, but an arc Line, it is then the optimal mixed ratio of metal grinding body in the peak of camber line.The HZ-12 groups of table 16 are then optimal abrasive bodies Grading distribution scheme.

By experiment, two kinds of abrasive bodies load in mixture and following characteristics be present：1. total useful load is constant, abrasive body is filled in mill Rate changes and changed with two kinds of abrasive body additional proportions, and increase ceramic grinding body ratio filling rate increases, and increases metal grinding body Then filling rate declines ratio.2. the weight ratio (or volume ratio) between two kinds of abrasive bodies has one most with total filling rate in mill Good equalization point, now mill efficiency is best；Rather than filling rate or metal grinding body ratio it is the higher the better.3. metal grinding body Addition enhance percussion, the correlation of grinding effect and abrasive body list ball weight is no longer close；But with the abrasive body gross area In the presence of stronger dependency relation (see the relation of the abrasive body gross area of accompanying drawing 6 and mill output), the big person's mill efficiency of the gross area It is high.

(2) judgement of HZ-12 grading distribution schemes feasibility and power savings

A) feasibility judges

Table 17 has related parameter calculating using grinding operational factor before and after ceramic grinding body and design first

Judged with the judgement formula in step of the present invention (7)

HZ-12 designs：18.61 ＜ 820/31.45=26.07 concept feasibles

B) HZ-12 grading distribution schemes power savings

①

=3200-820=2380 (KWh/h)

=2380/191.39=12.44 (KWh/t)

=3405/191.39=17.79 (KWh/t)

=12.44+17.79=30.23 (KWh/t)

=31.45-30.23=1.22 (KWh/t)

7. the economic benefit of year economize on electricity

Mill hourly output 191.39t/h, running rate calculate by 80%, produce 134.13 ten thousand tons of cement, economize on electricity 163.64 per year Ten thousand KWh, 0.58 yuan/KWh of electricity price, annual 94.91 ten thousand yuan of saving expense.This programme year economic benefit is created to be far longer than because of the underproduction The profit on sales of (130,000 tons) reductions.

With the progress of grinding technology, the big multi-configuration large-scale roller press of cement grinding system at present, if the system is equipped with ф 180 × 140 large-scale roller press effects can be more preferable.For the grinding system of this example, the appropriate storehouse metal grinding body dress of increase by one Carrying capacity, further enhance pre- milling capacity；Or grind the cement of the good grind materials such as incorporation flyash, lime stone, it will obtain more Big economic benefit.

(3) calculating of small barreling mill body grit level parameter is ground greatly

The small mill useful load of HZ-12 grading distribution schemes design is 90kg, and wherein 10 × 10mm of ф metal segments 35kg is remaining 55kg75% is ф 13mm Ceramic Balls, 25% ф 15mm Ceramic Balls.

A) small mill grit level parameter calculates

1. metal grinding body filling rate=[(abrasive body mass ÷ abrasive bodies unit weight) ÷ grinds dischargeable capacity] × 100

=[(0.035 ÷ 4.7) ÷ 0.098] × 100=7.59 (%)

2. ceramic grinding body filling rate=[(abrasive body mass ÷ abrasive bodies unit weight) ÷ grinds dischargeable capacity] × 100

=[(0.055 ÷ 2.2) ÷ 0.098] × 100=25.46 (%)

3. ф 10 × 10mm metal segments useful load=35 × 100%=35 (kg)

4. ф 13mm Ceramic Balls useful load=55 × 75%=41.2 (kg)

5. ф 15mm Ceramic Balls useful load=55 × 25%=13.8 (kg)

6. the total useful load=55+35=90 (kg) of abrasive body

7. the total filling rate=7.59+25.46=33.05 (%) of abrasive body

B) mill grit level parameter greatly calculates

1. metal grinding body useful load=grinding machine dischargeable capacity × filling rate × abrasive body unit weight

=117.57 × 7.59% × 4.7=41.9 (t)

2. ф 10 × 10mm metal segments useful load=41.9 × 100%=41.9 (t)

3. ceramic grinding body useful load=grinding machine dischargeable capacity × filling rate × abrasive body unit weight

=117.57 × 25.46% × 2.2=65.9 (t)

4. ф 13mm Ceramic Balls useful load=65.9 × 75%=49.4 (t)

5. ф 15mm Ceramic Balls useful load=65.9 × 25%=16.5 (t)

6. the total useful load=41.9+65.9=107.8 (t) of abrasive body

7. the total filling rate=7.59+25.46=33.05 (%) of abrasive body.

Claims

1. a kind of quick method for determining cement ball mill ceramic grinding body optimum gradation, comprises the following steps：

(1) before using ceramic grinding body, i.e.,：During with metal grinding body, cement grinding system is demarcated；

(2) measure is by the relative grindability of grinding material：

The material of various desire grindings and cement test normal sand are compared into table by test mill separate compiling same time, measure Area, the ratio of each material specific surface area and normal sand specific surface area is calculated, obtained by the relative grindability of grinding material；

(3) mill feed material of small mill experiment is selected：

The fineness of small mill experiment materials should approach with initially entering the material in two storehouses after one storehouse grinding of excessive mill；

It is thin according to each position material of system calibrating in the case of the fineness data for entering two storehouse materials are obtained in step (1) Degree situation, determine small mill experiment materials feeding place；

(4) ceramic grinding body grading distribution scheme designs：

First on the basis of 1.2-1.4 times of original metal grinding body filling rate, fixed abrasive body useful load, it is averaged in abrasive body In the range of single ball weight 5-12g, it is a test group every 1.5g, designs a series of grinding body gradation schemes；Looked for by small mill experiment Go out the averagely single ball weight of abrasive body and the relation of mill efficiency, therefrom primarily determine that preferred scheme；Raising abrasive body is carried out to it to fill out The experiment of rate is filled, filling rate is chosen according to power savings；To selected compared with abrasive body specification in the preliminary preferred scheme of high fill-ratio Ratio is suitably adjusted, and forms the grading distribution scheme that several groups of averagely single balls fluctuate again, and grinding experiment is carried out with small mill, wherein Mill efficiency highest is optimal grinding body gradation scheme；

(5) small milling mill test operation；

(6) big mill yield is calculated with small mill result of the test：The ratio surface of different grinding times from the small mill experiment of each grading distribution scheme In product value, the specific surface area value for reaching two grinding times before and after specific surface area of finished products is chosen, tries to achieve specific surface area per minute Rate of change, calculate the time required for various kinds group grinding to finished product requirement specific surface area.According to use instead ceramic grinding body it Actual production preceding and when using ceramic grinding body first, and their small mill simulated test grindings are to finished product requirement specific surface area Time difference, calculate ceramic grinding body and often extend 1 minute influence value to big mill yield than metal grinding body, and then calculate and respectively set The big mill yield that meter scheme can reach；

(7) judgement of grading distribution scheme feasibility：According to before changing, change rear abrasive body useful load and yield, ball milling motor and other set Standby power consumption, carry out the judgement of grading distribution scheme feasibility；

(8) ceramic grinding body operational version is adjusted according to process capability：

When the warehouse receipt of grinding machine two is pure can not meet economize on electricity target call using ceramic grinding body, based on material grindability and pre- grinding Ability, extend a storehouse length, correspondingly shorten two storehouses, increase by a storehouse metal grinding body useful load；It can not still meet to require When, then two storehouses take ceramic grinding body to be loaded in mixture with metal grinding body；

(9) two storehouse grinding body gradations of big mill are calculated according to small mill grinding body gradation.

2. according to the method for claim 1, wherein step (1) further comprises：

B) the fineness situation of change of each position material in process is determined, analyzes the pre- milling capacity of roll squeezer system；Roll-in It is supplied to 45 μm of the material into ball mill to tail over content after machine extruding and should be less than 35%-45%；

C) grinding system yield is demarcated, counts ball milling motor and the power consumption of other equipment respectively, calculates ton cement output power consumption.

3. according to the method for claim 1, wherein step (4) further comprises：

Gradation design is based on big grind, it is first determined the filling rate of abrasive body and the blend proportion of different size abrasive body, institute It is identical for size mill to state two parameters；Dischargeable capacity according to large and small mill calculate respectively the total useful load of abrasive body and The weight of each specification abrasive body, then carries out simulated test with the result of calculation of small mill, and calculation formula is as follows：

The total useful load of abrasive body=grinding machine dischargeable capacity × filling rate × abrasive body unit weight

B) fixed abrasive body useful load, primarily determines that preferred grinding body gradation

Preferred scheme is primarily determined that, it is necessary to design according to the following steps from average single ball weight or the relation of the gross area and mill efficiency A series of grinding body gradation schemes：

1. each group grading distribution scheme designed should meet claimed below

1) ceramic grinding body filling rate is determined with 1.2-1.4 times of big mill metal grinding body filling rate originally；

2) 2-4 kinds typically can be selected in abrasive body specification；It should be greater than for spherical grinding body or equal to 3 kinds；

3) select in the range of the averagely single ball weight 5-12g of abrasive body, be a test group every 1.5g, design a series of grinding body gradations Scheme；

4) under conditions of the averagely single ball weight of setting abrasive body, the maximum abrasive body gross area should be kept；

2. the design method of each group grading distribution scheme

" programming evaluation " computational methods in " Excel " software are utilized quickly to try to achieve the scheme for meeting above-mentioned requirements；

C) carry out improving the experiment of abrasive body filling rate, filling rate is chosen according to power savings；

D) the selected preliminary preferred scheme compared with high fill-ratio is suitably adjusted, forms what several groups of averagely single balls fluctuated again Grading distribution scheme, grinding experiment is carried out with small mill, wherein mill efficiency highest is optimal grinding body gradation scheme.

4. according to the method for claim 1, wherein step (5) further comprises：

A) body weight is respectively ground according to the abrasive body useful load and different size proportion requirement of design, precise, loaded Test mill；

B) doses for often grinding loading is controlled in 5-10kg according to grindability is different；

C) each mill point some time is sampled to calculate fineness rate of change；

D) after every group of material grinding, abrasive body and material are poured out in the lump, with different pore size sieve by abrasive body by different size point Open；

E) after being cleaned up in mill with material on abrasive body, lower battery of tests is carried out；

F) determine the material after grinding tails over fineness and specific surface area.

5. according to the method for claim 4, wherein in the step c), the period is typically at intervals of 5-10 points Clock, each sampling amount control is in 150-200g；Sampling starting and time general control is terminated in 15-40 minutes, can be according to material Grindability suitably adjusts.

6. according to the method for claim 1, wherein step (6) further comprises：

A) change rear different abrasive body species and grading before being changed with the small big mill of mill simulation and carry out grinding experiment, calculating is milled to finish fineness Grinding time used in it is required that, with the time difference of the two, calculate ceramic grinding body and often extend 1 minute than metal grinding body to big mill The influence value a of yield：

A=(changes preceding yield W_Q- change rear yield W_H) ÷ (ceramic grinding body grinding time Ti- metal grinding bodies grinding time Tj)；

B) specific surface area rate of change Si per minute in various kinds group certain time interval Δ t is calculated：

Ti=t1+ [(M-t1 specific surfaces product value) ÷ Si]

D) various kinds group grinding time Ti and virgin metal grinding body gradation grinding time Tj difference Δ Ti is calculated：

Δ Ti=Ti-Tj

Δ Wi=Δs Ti × a

F) various kinds group is asked to grind yield Wi greatly accordingly：

Wi=W_Q–ΔWi。

7. according to the method for claim 1, wherein step (7) further comprises following judgment step：

A) derivation of formula is judged：

The synthesis power consumption of grinding system is made up of ball milling motor power consumption and other equipment power consumption two parts, system synthesis unit before changing Shown in power consumption such as following formula (1)：

Change rear system synthesis unit power consumption and be then changed into following formula (2)：

From above-mentioned (1) (2) relational expression, reduction power consumption could be realized when formula (2) is less than formula (1)；

If it is a to change the electromechanical consumption of forecourt electric mill, other equipment power consumption is b, and yield is c before changing, using ball milling electricity after ceramic grinding body It is m that machine, which saves power consumption, and yield reduction amount is n, makes formula (2)≤(1), obtains inequality (3)：

Derive to obtain formula (4)：

WhereinTo change the inverse of preceding comprehensive unit power consumption；

From relational expression (4), when yield reduction amount is more than or equal to comprehensive unit power consumption before ball milling motor is saved power consumption and changed Ratio when, grinding system can not realize the effect of economize on electricity, then grading distribution scheme is infeasible；

B) gradation design scheme power savings are calculated：Using before changing, change rear creation data, calculate design synthesis unit electricity Consumption, when virgin metal abrasive body compared with；By ball milling motor power saving amount that gradation design scheme calculates, the yield compared with before changing Reduction amount substitutes into formula (4), you can judges the feasibility of design.

8. according to the method for claim 7, wherein in step b), calculation procedure is as follows：

①

2. design ball milling motor power consumption=virgin metal abrasive body ball milling motor power consumption-design ball milling motor power saving Amount

6. unit power consumption-design synthesis unit is integrated during design synthesis unit power consumption reduction amount=virgin metal abrasive body Power consumption

9. according to the method for claim 1, wherein in step (8), the small mill experiment that two kinds of abrasive bodies load in mixture is included such as Lower step：

A) selection of ceramic grinding body specification

Strengthen due to adding metal grinding body rear impact, thus selected the less ceramic grinding body of two kinds of specifications to ensure The gross area of abrasive body；

B) selection of metal grinding body species and specification

With reference to the preferable scheme tested entirely with ceramic grinding body, select abrasive body total useful load, be separately added into equivalent metal ball or Metal segments carry out grinding experiment, and the species of metal grinding body is determined with the high person of specific surface area rate of change.Then single ball weight is selected With larger ceramic grinding body similar in two kinds of specifications metal grinding body, then respectively carry out grinding comparison, select metal grinding body Specification；

In the case where two kinds of abrasive bodies load in mixture, the additional proportion of metal grinding body is stepped up, ceramic grinding body ratio is corresponding Diminish, and gradually increase total useful load, filling rate increases therewith, designs a series of small mill testing programs；To small mill result of the test Big mill yield is extrapolated with the method for step (6), and carries out regression analysis, graph of relation is drawn, finds out optimal metal and grind Mill body additional proportion and total useful load, as optimal grading distribution scheme；

Grading distribution scheme feasibility is judged with the method for step (7) and performance analysis, carry out actual production checking, so as to really Surely it is applied to the optimal grading distribution scheme of actual production.

10. according to the method for claim 1, wherein the step (9) comprises the following steps：

A) filling rate of ceramic grinding body and metal grinding body in small mill is obtained respectively：

B) volume shared by ceramic grinding body and metal grinding body in two storehouses of big mill is obtained respectively：

C) ceramic grinding body and metal grinding body Weight Loaded in two storehouses of big mill are obtained respectively：