CN1055526A

CN1055526A - Refined kaolin calcined from kaolinite

Info

Publication number: CN1055526A
Application number: CN 90101929
Authority: CN
Inventors: 王自耕; 赵立建
Original assignee: ZHONGKE INST OF MATERIALS ENGINEERING BEIJING CITY
Current assignee: ZHONGKE INST OF MATERIALS ENGINEERING BEIJING CITY
Priority date: 1990-04-12
Filing date: 1990-04-12
Publication date: 1991-10-23

Abstract

The characteristics of refined kaolin calcined from kaolinite of the present invention are: kaolinite is ground to 10～160 orders through comminuted powder, stirs after adding water then, is pressed into the vesicular object, carries out roasting then.Below 400 ℃, last 4 hours and dry, last 3 hours at 600 ℃ and slough crystal water; Constant temperature calcining is 12 hours under 800～925 ℃ temperature, makes organic oxidation abundant.Carry out grinding after the cooling again, reach requirement of strength, handle, become refining kaolin through deironing.

The present invention can be chemical industry, papermaking, electronic ceramics etc. material is provided.

Description

Refined kaolin calcined from kaolinite

Kaolin is more purified kaolin families from chemical ingredients, and impurity is few, can be used as the compound and the batching of a lot of products: as, rubber, plastics, chemical industry, papermaking, electronic ceramics, paint etc.Use it to improve the quality of products, reduce cost.But good like this starting material do not obtain good development and application so far.Kaolinic application China is mainly used in ceramic industry, mixes in ceramic batch, both do not purify, also not calcining, reduced its use value as the hard clay.Also useful it calcine mullite, its production technique is very backward.Calcine blocky kaolinite, utilize down-draft kiln to need just can burn till a kiln, and be not kaolin with the time of two weeks, but mullite.Calcined powder shape material also needs several days time, and output is very low, the extremely difficult control of production technique.Purpose of the present invention is exactly in order to produce the needs that large batch of smart matter kaolin satisfies every profession and trade, to give full play to its effect.

Characteristics of the present invention, the characteristics of its production technique just, that is: kaolinite through fragmentation, grinding, add water and stir moulding, grinding again after the roasting becomes refining kaolin after the purification.Kaolinite adds 13～16% moisture content through crushing and grinding to 10～160 orders, stirs, and utilizes shaper to be pressed into the vesicular object.Intensity should not be too high, can not be too low.Could will add water evaporation oven dry like this, temperature can not be higher than 400 ℃, about about 4 hours, moisture content is fully evaporated totally.If the high poroid thing of temperature can be cracked, cause roasting bad.If temperature is too low, drying time is long, influences the raising of output.After the oven dry, temperature is brought up to 600 ℃, the crystal water in the kaolinite is deviate from, need three hours time.After most of crystal water is deviate from, temperature is brought up to 925 ℃.Carry out constant temperature calcining, last 12 hours, make the abundant oxidation of organism in the kaolinite.Pulverize again through cooling, reach the required fineness of every profession and trade, generally at 325 orders.Then the iron powder in the thin process of powder is removed, become purified kaolin.

After the crushing and grinding moulding, roasting is grinding more again for elite of the present invention and key.Kaolinite is after the crushing and grinding moulding, and density reduces greatly than former stone, and organic matter obtains homogenizing.Help the organic oxidation in the starting material, organic matter becomes CO ₂Expel from kiln.The forming composition outside surface has formed countless fine apertures like this.Under middle mild oxidation atmosphere, organic aperture is progressively deepened along aperture continuation oxidation, till the organic fully oxidation of forming composition inside is intact.Former stone becomes the condition that poroid thing has not only possessed abundant oxidation, and helps heat exchange, the thermal radiation of kiln wall, the thermal conduction of storeroom, and the hot gas flow in the kiln, make the very fast rising of temperature of forming composition, accelerated rate of roasting, the block and not available condition of powder of roasting at this moment.The roasting lumpy material is because the density height lacks oxygen, so roasting is very slow.The roasting pulverulent material owing to cannot form fine aperture, lacks oxygen, organic oxidation also very slow.So this is to produce the kaolinic best approach of smart matter for the grinding shaping and roasting.

Embodiment: utilize the annealing furnace type, the kaolinite in somewhere is carried out roasting.At first with kaolinite crushing and grinding to 10～160 orders, add 13～16% water and stir, utilize shaper to be pressed into the object of honeycomb coaly, advance the kiln roasting.At first dry with 4 hours time, temperature is below 400 ℃.Slough crystal water then, in the time of with 3 hours, temperature is below 600 ℃.Temperature is mentioned 925 ℃, and constant temperature 12 hours carries out roasting.Grinding again after the cooling, the iron of removing in the grinding process becomes refining kaolin.After testing and chemical analysis: material becomes white by original grey, and whiteness is not less than 85 degree, and lattice shape is the sheet lattice.Chemical ingredients is: SiO ₂53.5～53.75%,

Al ₂O ₃45.25～45.5%，

Fe ₂O ₃0.1～0.3%，

CaO 0.03～0.1%，

NaO 0.06～0.08%，

K ₂O 0.05～0.07%，

TiO ₂0.038～0.1%，

MgO 0.04～0.10%，

P ₂O ₅0.32～0.5%

Such whiteness, lattice, chemical ingredients just determined it be various products dose material and good chemical raw material.

Effect of the present invention can make kaolinite become ideal kaolin, and result of use is good, applied range.In the use of high-voltage cable, other compound resistance values of replacement 25% can improve 5～6 times.And can play half strengthening action.In plastics, use in the resin building-up process, to produce good thixotropy, improve the insulativity of cable foreskin.Use in paint that not only suspension is good, and replace the part titanium dioxide.In electroceramics, use and to improve its insulativity.The processing molecular sieve can reduce cost.

Remarkable in economical benefits of the present invention is estimated to produce 5000 tons factory per year, invests 2,500,000 yuan, and product cost is 400 yuan/ton, and 800 yuan/ton of prices, profits tax are 400 yuan/ton, and annual return is 2,000,000 yuan.

The refined kaolin calcined from kaolinite technological process of production.

Kaolinite → grinding → add water, stirring → moulding → roasting → grinding → purification → finished product

Claims

1, kaolinite adds the moisture of water 13～16% through crushing and grinding to 10～160 orders, stir, and compression moulding, grinding again after the roasting, deironing is purified to purified kaolin.

2, according to power " one's " requirement, the kaolinite behind the grinding must add water and stir compression moulding.

3, according to power " one's " requirement, the kaolinite after the moulding will be at 800～925 ℃ of roasting temperatures.