French chalk exceeds grinding process of physico-chemical property change

  • Exceeding grinding is the important step of stock deep treatment, its are main the purpose is to be modern industry, especially industry of new and high technology offers high-powered powdery system product. A lot of research make clear. The author ever exceeded the structural change of grinding process to undertake an analysis to French chalk. This job basically considers to exceed grinding to wait for content to change the effect of property to potential of French chalk Z, whiteness, fuel factor and embellish damp and hot.

    1 experiment is ground with agitate exceed grinding French chalk (one 325 eye 100% ) medium grinds mine chroma for the zirconia ball Mm for 55% , ball makings is compared for 4 fine grind to the sampling after proper time, via smoking filter, drying, can use at detecting. Potential of powdery body Z is detected by Zetaplus ― ZetaPotentialAnalyser. Check the whiteness of powdery body with ZBD whiteness appearance.

    1 difference of ― heats up analyzer (warm up 10C/min) into foundation project: Fund of paper of outstanding doctor's degree aids financially Hunan Province project (number 2 ⑴ 114) .

    The analysis differring heat of travel pink body (DTA) embellish damp and hot by French SETRAMC80 minim heat plan determines. With SKC ― 2000 model the average bead diameter of body of pink of test of analyzer of the smooth granuality that show pattern (D50) .

    Closely related 2 results and the physico-chemical property that analyse the Z potential of 2.1 pink body to exceed fine pink system and its application, it affects the adsorption that exceeds fine pink system, profit directly wet, surface can reach other surface action. French chalk classics exceeds fine the granuality after grinding is refined ceaselessly, the area that compare a list increases ceaselessly (see a table 1) besides granuality decrescent, through checking the Z of powdery body potential can see, french chalk granuality is finer, its surface moves potential (Z potential) negative watch is big, the specification is worth a condition to fall in same PH, fine character of surface of the French chalk after grinding is more active, exterior active is stronger.

    Be like / / justice the whiteness whiteness of body of M 2.2 pink is to exceed fine pink system especially industry is mineral exceed fine pink system a very main character, it matters to its to reach the applied result in composite material in coating of papermaking, paint directly. After the course exceeds grinding, the whiteness of steatitic Fen body increased nearly 3 percent than raw ore (see) . Because,this may be as fine grind undertake, granuality is reduced, the area that compare a list increases, exterior active increases, the reflectivity of powdery body greatens, and the hole of surface of powdery body grain decreases, make whiteness rises. The DTA analysis of 2.3 pink body can see from which, after French chalk course exceeds grinding, its feature peak moves to microtherm direction, fall respectively by the C of 815 904 ° of raw ore to 791, the 877 fuel factor that improved powdery put oneself in another's position, this explained the reason that exceeds fine pink physical ability to drop material firing temperature adequately also.

    The degree that powdery body melting point drops can express with next type: Exceed fine pink body to basically be used at the preparation of contemporary new material, melting point is reduced, exterior active rises, can simplify manufacturing technology, improve material performance. Exceed fine French chalk to be in pottery and porcelain of steatitic porcelain, answer photograph, steatitic base iron ore of exceedingly good characteristic Ceng Yonghuang, calcite and magnesite already were shown to make raw material in functional pottery and porcelain and treatment of polymer composite material, in " quantity heat is ground machine " inside fine grind, determined before mill, hind stock dissolve antifebrile changes, do not have the report of this respect all the time later. In fact, damp and hot of profit of research pink system is followed super- fine the change that grind is active to understanding its have important sense.

    The experiment inspected water to grind the exceeds fine French chalk embellish damp and hot after exceeding grinding 2h to change to raw ore French chalk and agitate (see) , can see fine the water after grinding is more intense to the embellish wet process of powdery body, and raw ore is relatively slow. From inside the metabolic value that expresses 2 embellish damp and hot apparently, exceeded grinding to raise the active of powdery body greatly.

    Express the curve of dynamic thermal current that 2 exceed grinding to exceed fine French chalk to the influence of damp and hot of powdery system profit the area comparing a list that 3 exceed what the thermodynamic agitate of grinding process grinds to exceeded grinding to increase powdery put oneself in another's position, the internal energy of the grain of new student of one part translate into in inputting energy and surface can. Powdery body gets the action of outside force, arise above all be out of shape, internal energy increases, if at this moment the bulk of powdery body is changeless, criterion if the volume of powdery body happened metabolic AV to have AU=TAS=PAy+AA in the process here,the change of internal energy is (3) among them: For freedom can; U is entropy for internal energy; T is temperature; S is be out of shape stress; P is the pressure that grain place gets; Al is the change of grain linear dimension; AA is the mechanical result that generation is out of shape place needs.

    When stock exceeds grinding, its are free can change is the biggest among them: For the average specific heat capacity inside At of temperature change interval; Ef expresses the energy that area place requires newly to produce an unit; AF is the new face that arises because of exceeding grinding place to accumulate.

    As a result of internal energy and surface can increase, add the effect such as mechanical activation, the property of body of the pink after the course exceeds grinding all can have the change of different level.

    French chalk classics exceeds 4 conclusion after grinding, powdery body is reduced except granuality, outside increasing than expressing an area, its active and exterior report also produce change, whiteness increased 3 percent, z potential is lost more greatly, reduced the DTA feature peak value of powdery body at the same time, make the temperature of OH+ reduced 20 ° C, powdery body active rises apparently.

    (2) exceed system of grinding process pink closely related thermodynamic character and its character change.