CN103755167B

CN103755167B - A kind of preparation method of pozzolana mixed material in cement

Info

Publication number: CN103755167B
Application number: CN201410020717.2A
Authority: CN
Inventors: 彭美勋; 叶真男; 邹高增
Original assignee: Hunan University of Science and Technology
Current assignee: Hunan University of Science and Technology
Priority date: 2014-01-17
Filing date: 2014-01-17
Publication date: 2018-05-22
Anticipated expiration: 2034-01-17
Also published as: CN103755167A

Abstract

A kind of preparation method of pozzolana mixed material in cement, one is fills 0~8.6% sodium carbonate or sodium hydroxide that alkalinity is dry tufa stone in weathering tuff-powder, in a manner of grinding after mixing when 300~750 DEG C of calcinings 2~3 are small.Secondly be added in weathering tufa stone 0.5~3% soda ash, add Forced Dispersion 20~60 minutes after aqueous, continue to be diluted with water and laitance is thrown aside after sufficient standing, so repeat plus water is repeatedly washed, until water is gone to dry precipitation after laitance clarification.This method process is simple, of low cost, and gained mixing material activity is high, for prepare cement be conducive to it is energy-saving.

Description

A kind of preparation method of pozzolana mixed material in cement

Technical field

The invention belongs to building material field, the preparation sides of particularly a kind of pozzolana mixed material in cement Method.

Background technology

Tufa stone is the rock that the volcanic ash migration accumulation after mainly being erupted by volcanic rock is formed, and primary chemical composition is Based on silica and aluminium oxide, secondly oxide also containing alkali metal oxide and a small amount of iron；Chemical composition is except possible altogether Landwaste and brilliant bits it is outer, usually also contain vitroclastic.The volcanic glass of vitroclastic in tufa stone, that is, usually said, is that tufa stone has The main reason for pozzolanic activity.Therefore, tufa stone is most often applied and mixed in cement as a kind of raw material with pozzolanic activity Solidifying soil field（CN102007085A）, can also be directly used as construction material（CN1087071A）.But the tufa stone through Weathering And Leaching The complicated clay mineral such as normal kaolinite containing montmorillonite, and often in loose light fine powder output.Clay pit therein Object is difficult to be separated from Pozzolanic feature substance, therefore is difficult to directly utilize.

The content of the invention

Pozzolana mixed material of the present invention in cement refers to by GB/T 2847-2005 (for cement Pozzolana mixed material) defined in the natural or artificial mineral material with Pozzolanic feature.

It is prepared it is an object of the invention to provide a kind of using weathering tufa stone for the calcareous addition of volcano in cement The method of material can handle weathering tufa stone raw material at low cost, as the activity mixing for preparing cement according to the characteristic of raw material Material.

Embodiment of the present invention is the preparation method of a kind of pozzolana mixed material in cement, including right Weathering tufa stone carries out two methods of dry and wet processing, can independently obtain calcareous addition of volcano of the present invention Material.

The dry method comprises the following steps：

（1）Sodium carbonate or sodium hydroxide are filled in the tufa stone of weathering, is ground in any way together with 200 targets During quasi- sieving, the quality of oversize less than 10%, wherein the incorporation of sodium carbonate or sodium hydroxide according to contained Na2O quality meter It calculates, to dry the 0~8.6% of tufa stone.

（2）After levigate burning native powder calcined in the range of 300~750 DEG C 2~3 it is small when.

This method adds raw material alkali calcining to have method easy, and technological parameter adjustable extent is big, easily operated, adaptable The features such as.Can pretreating process be adjusted flexibly according to specific raw material and appointed condition.Its calcining heat is low and calcining heat and plus The equal adjustable extent of alkali number is wide：Both can low temperature burn till to 300 degree, also can low alkali and alkali-free burn till, therefore both may be selected to be not added with alkali The low equipment investment method of low temperature calcination also may be selected in cost effective method.

The wet method comprises the following steps：

（1）The soda ash for accounting for tufa stone quality 0.5~3% is added in weathering tufa stone, then adds water, passes through high speed shear Mashing or wet ball-milling 20~60 minutes make most of particles in slurry cross 200 mesh wet screenings, and wherein amount of water is meets slurry Minimum amount needed for mobility.Appropriate dispersant or grinding aid can be also added in before mashing or wet-milling as needed.

（2）Underflow is diluted in sedimentation basin according to the definite amount of water for the first time of experiment first, slurry is stirred evenly rear quiet It puts, often the time removal depth l of standing >=t₂Then above slurry supplements the water isometric with removing slurries into container, It repeats above-mentioned standing, shifting slurry and water-refilling operation repeatedly to rinse tufa stone, when the top slurry that last time removes reaches After clarification, no longer moisturizing.

（3）Lower part precipitation obtains pozzolana mixed material powder by filtering water removal and after drying.

Step（2）In, determining the test method of amount of water for the first time is：By the even slurry sample after arbitrary water is added to dilute flat Stand in foundation shape glass container, demarcate the apparent beds of precipitation with top suspension if lower vessel portion can be observed and have, show plus Water reaches requirement, otherwise, it is necessary to whether continuing to be diluted with water and determine amount of water suitably in the same way.

Step（2）In, the time t and depth l₂It is determined by following methods：Even slurry after diluting for the first time is sampled Sufficient standing stablizes constant, record precipitation layer depth l to layer depth is precipitated in flat column glass container₁, slurry total depth L, if slurry total depth is L, then l in sedimentation basin₂It is determined respectively by two following formula with t：

The unit of all length is rice in formula, and the unit of time is hour.

The characteristics of this wet method is need not to add alkali calcining, escapable cost and energy consumption, but production efficiency is suitable for not as good as dry method Situation about being comprehensively utilized simultaneously to the clay selected.

Specific embodiment

With reference to embodiment, the present invention is described in further detail.Device therefor is conventional in the embodiment of the present invention Equipment, raw materials used is convenient source.

The main object of certain typical weathering tufa stone is mutually micron-sized volcanic glass chip, is secondly a small amount of quartz-crystal Bits, due to weathering, there are considerable a variety of containing constitution water and intermediary water including kaolinite, illite and montmorillonite Clay mineral；Strong Weathering And Leaching causes fine lithology to be broken into superfine canescence bulky powder shape, and 0.8mm standard screens pass through Rate is more than 95%.The chemical composition of the tufa stone is as shown in table 1.

The preparation of dry method pozzolana mixed material：By the way that representative sample analysis is taken to determine that it adsorbs water content, then Suitable sodium carbonate or sodium hydroxide are uniformly mixed on request and is fully mixed and stirred, and temperature is adjusted in the range of 300~700 DEG C and is carried out Calcining, when the maximum temperature heat preservation 2 of setting is small.The working process parameter of each embodiment is shown in Table 2.In table 2, sodium carbonate or hydrogen-oxygen The incorporation for changing sodium is its actual mass.

The preparation of wet method pozzolana mixed material：Add a small amount of water and appropriate soda ash in weathering tufa stone powder, in glue Different time is ground in bucket with the mashing of high-speed shearing machine high speed or in ball mill.Slurries are crossed into 200 mesh wet screenings, are discarded on sieve Object.Then the different ratio of muds is diluted with water in thick slurry（The mass ratio of water and tufa stone dry powder）.Slurry sample is taken to be statically placed in In graduated cylinder, treat that boundary line to the beds of precipitation and slurries is clear and steady Timing measurement depth of precipitation l₁With the ratio of slurry total depth l.Glue The depth L of bucketful slurries is 0.30m in bucket, will have been diluted in glue bucket and has removed upper layer depth with siphon pipe after slurry time of repose t l₂Then above slurries add water to the depth before removing again, stand after slightly stirring and removed together with after previous identical time t Sample depth l₂Above slurries.Siphon nozzle is kept close to slurry surface when removing slurries.The top slurry that last time removes Reach clarification and no longer add washing slurry.110 DEG C of drying pozzolana mixed materials are deposited in after pulp washing.Each embodiment Working process parameter is shown in Table 3.

By GB/T2847-2005（For the pozzolana mixed material of cement）Requirement detection pozzolana mixed material Main performance, testing result is shown in Table 4.As shown in Table 4, the main performance for the pozzolana mixed material that each example obtains is bright The aobvious requirement more than GB/T2847-2005 illustrates Pozzolanic feature of the mixing material with height that this method obtains, can be used as and live Property mixing material and clinker mix grinding produce cement.

Claims

A kind of 1. preparation method of pozzolana mixed material in cement, which is characterized in that the step including order below Suddenly：

(1) admixture contains Na in weathering tufa stone₂The quality of O is 3.875~8.6% sodium hydroxide of dry tufa stone, together When being ground to sieving quasi- with 200 targets in any way, less than 10%, the weathering tufa stone limits the quality of oversize For：Its main object is mutually micron-sized volcanic glass chip, is secondly a small amount of quartz crystal, due to weathering, there are considerable A variety of clay minerals containing constitution water and intermediary water including kaolinite, illite and montmorillonite；Strong Weathering And Leaching causes Fine lithology is made to be broken into superfine canescence bulky powder shape, 0.8mm standard screens percent of pass is more than 95%；

(2) levigate powder calcined in the range of 300~500 DEG C 2~3 it is small when.
A kind of 2. preparation method of pozzolana mixed material in cement, which is characterized in that the step including order below Suddenly：

(1) soda ash for accounting for tufa stone quality 0.5~3% is added in weathering tufa stone, then adds water, is beaten by high speed shear Or wet ball-milling 20~60 minutes, most of particles in slurry is made to cross 200 mesh wet screenings, throw aside oversize, wherein amount of water is Meet the minimum amount needed for fluidity of slurry, the weathering tufa stone is defined to：Its main object is mutually micron-sized volcano Secondly glass chip is a small amount of quartz crystal, is existed due to weathering there are considerable including kaolinite, illite and montmorillonite Interior a variety of clay minerals containing constitution water and intermediary water；It is loose that strong Weathering And Leaching causes fine lithology to be broken into superfine canescence Powdered, 0.8mm standard screens percent of pass is more than 95%；

(2) underflow is diluted in sedimentation basin according to the definite amount of water for the first time of experiment first, is stood after slurry is stirred evenly, often The time of standing >=t removes depth l₂Then above slurry supplements the water isometric with removing slurries into container；Repeat this Standing, shifting slurry and water-refilling operation repeatedly rinse precipitation, after the top slurry of last time removal reaches clarification, no longer Moisturizing；Wherein it is determined that the method for amount of water is for the first time：Even slurry sample after arbitrary water is added to dilute is held in flat column glass It stands in device, demarcates the apparent beds of precipitation with top suspension if lower vessel portion can be observed and have, show that amount of water reaches requirement, Otherwise, it is necessary to whether continuing to be diluted with water and determine amount of water suitably in the same way；The time t and depth l₂By with lower section Method determines：Even slurry after diluting for the first time is sampled to flat column glass container, sufficient standing is steady to layer depth is precipitated It is fixed it is constant after, record precipitation layer depth l₁With slurry total depth l, if slurry total depth is L, then l in sedimentation basin₂With t by following Two formula determine respectively：

T=50 (L-l₂)

The unit of all length is rice in formula, and the unit of time is hour；

(3) lower part precipitation obtained by step poly- (2) passes through dry after filtering water removal.