CN1041080C - Processing method for high-purity calcium oxide refractory material - Google Patents

Abstract

The present invention provides a method for preparing a high-purity calcium oxide refractory material. The present invention is characterized in that lime is used as raw materials, organic glass and acetone, or gasoline and paraffin wax, or anhydrous alcohol and calcium oxide slurry are used as binding agents, and the gasoline and the paraffin wax or asphalt are used as moisture prevention agents; the components are treated by the steps of proportioning, mixing, pressing into blocks, shaping, calcining twice and hydration prevention, and the high-purity calcium oxide refractory material with CaO content of 98% can be produced. The present invention has the advantages of cheap and easily-obtained raw materials, and simple process and equipment. The made material has high hydration resisting capability and is an ideal refractory material for smelting steel.

Description

Processing method for high-purity calcium oxide refractory material

The invention belongs to fire resisting material field.Mainly be applicable to and make highly purified calcium oxide refractory materials.

The fusing point of calcium oxide is a kind of ideal refractory materials that is used to smelt the high-quality steel up to 2750 ± 10 ℃, ought to and water in the steel system at the steel-making furnace lining to be widely used.But because calcium oxide has the characteristics of the moisture absorption (easily aquation), give production, accumulating, use this refractory materials and bring great difficulty.Fail widely to use always.

In the prior art, the 32nd page of the 3rd phase of " refractory materials " nineteen eighty-two and the 13rd page of development of having reported lime crucible once of 1989 the 2nd phases.They are to be raw material with chemical pure or analytical pure CaO or CaCO3, and moulding process manufacturings such as static pressure such as employing form, and its goods only are crucible.The starting material source is difficult for, cost is high, required producing apparatus complexity, and its goods limitation is big.

In 886 pages of " silicate dictionary " book, introduced a kind of lime refractory materials.The manufacture method of this refractory materials is to be raw material with Wingdale (or calcium hydroxide), through light-burned and pressure ball, again through the high-temperature calcination ripe material.Allocate grog particle, fine powder into a small amount of dehydration organism (as paraffin wax, pitch etc.), make goods through mixing, be shaped, burning till.The enforcement of this method is complicated and difficult, and is well-known, and dehydration organism paraffin or pitch are solid-state at normal temperatures, this goods and materials, and viscosity is big, can not grind to form fine powder, therefore, at normal temperatures, can not mix with grog, and subsequent processing is difficult to carry out.Common way is with the heating of paraffin or pitch, just can be used for spice after reaching certain flow state, and correspondingly, grog and agitator all must heat.So equipment, complex process, and certain danger.This also is that the calcium oxide refractory materials is failed industrial major reason always.

The object of the present invention is to provide a kind of manufacture method of new high-purity calcium oxide refractory materials, its raw material sources are wide, and cheap, and manufacture craft and equipment are simple, the calcium oxide fire resistive material product of made aquation not in half a year, and can make the refractory materials of all size and shape.

At above-mentioned purpose, processing method for high-purity calcium oxide refractory material of the present invention comprises the steps (operation):

Raw material is equipped with, removes surface inclusion, lime slaking becomes lime white and filtration, oven dry briquetting (die mould), calcining, pulverizing, batch mixing, moulding, sintering (burning till), preventing hydration processing, encapsulates.

Now that each step (operation) division is as follows:

(1) raw material is equipped with

Raw material of the present invention adopts lime and anhydrous binder, and its proportioning raw materials (weight %) is: lime 80-95%, anhydrous binder 5-20%.

Anhydrous binder be in synthetic glass acetone, gasoline paraffin or the dehydrated alcohol calcium oxide mud any.

(2) remove surface inclusion

Adopt physical method (as sieve etc.) to remove the inclusion in the lime.

(3) lime slaking becomes lime white, and filters

Water becomes lime white with the lime slaking through removing inclusion, and filters, and removes the inclusion in the lime white, improves the purity of lime white.

(4) oven dry, briquetting

Lime white is dried after filtering, is pressed into waste base after the oven dry again.

(5) calcining

The waste base of compacting is put into calcining furnace calcine, so as mature calcined material, its calcining

Temperature is 1450-1750 ℃, and calcination time is 10-36 hour.

(6) pulverize

Chamotte powder after the calcining is broken into fine powder.

(7) according to proportioning raw materials, the lime powder grog added in the batch mixing in the lump with anhydrous binder mix, make compound.

(8) moulding

As required, compound is made the parison of different shapes and specification.

(9) sintering (burning till)

Final parison is put into moistureproof calcining furnace carry out sintering, sintering temperature is 1400-1700 ℃; Sintering time is 13-25 hour.

(10) preventing hydration is handled

The calcium oxide fire resistive material product that sinters, after coming out of the stove, immerse gasoline--in any non-blushing thinner in-paraffin or the pitch, carry out preventing hydration and handle, treatment time 4-25 minute, after treatment, promptly become the final calcium oxide fire resistive material product of the present invention.Goods encapsulate through plastics bag, so that accumulating.

Adopt the made calcium oxide refractory materials of the present invention, its purity can reach CaO＞98%, and aquation not in half a year can be made into different shape and specification refractory materials, is widely used in making steel furnace lining and watering in the steel system, is the ideal refractory materials of smelting the high-quality steel.

Compared with prior art, the present invention has following advantage:

(1) can make CaO＞98%, different shape and specification, the high-purity calcium oxide refractory materials of preventing hydration again.

(2) raw material sources are easy, cost is low.

(3) manufacture craft and equipment are simple.Particularly lime white and anhydrous binder batch mixing only need can carry out at normal temperatures, need not heat.

Embodiment

Adopt manufacture method of the present invention, made five batches of high-purity calcium oxide refractory materialss.The raw material that is adopted and the proportioning of anhydrous binder are as shown in table 1.Twice incinerating processing parameter before and after table 2 has been enumerated, it is as shown in table 3 that preventing hydration is handled used non-blushing thinner and treatment time.

Goods specification, ultimate compression strength and the high-temperature oxidation resistance of five batches of high-purity calcium oxide refractory materialss of made are listed table 4 in.Five batches of goods place under the normal temperature atmosphere, after six months, do not find hydration phenomena yet.

Table 1 embodiment raw material and anhydrous binder proportioning (weight %)

Lot number	Lime	Anhydrous binder
					Synthetic glass acetone	Gasoline paraffin	Dehydrated alcohol calcium chloride mud
		1	82	18				/	/
2	80				20	/	/
		3	85	/				/	15
4	94				/	6	/
		5	93	/				7	/

Twice incinerating processing parameter of table 2 embodiment

Lot number	Calcining for the first time		Calcining for the second time
					Calcining temperature ℃	Calcination time hour	Calcining temperature ℃	Calcination time hour
	1	1750	10	1580					25
2					1450	14	1580	15
	3	1680	36	1400					25
4					1680	36	1700	13
	5	1580	13	1570					18

Used non-blushing thinner of table 3 embodiment WATER REPELLENT and treatment time

Lot number	1	2	3	4	5
						Non-blushing thinner	Pitch	Pitch	Pitch	The gasoline paraffin wax	The gasoline paraffin wax
Treatment time	10 minutes	15 minutes	20 minutes	5 minutes	5 minutes

Table 4 embodiment goods specification and physicals

Lot number	Product size mm	Compressive strength MPa	CaO content %
				1	50×50×70	18	99.2
2	φ70×70	18	99.2
				3	φ70×70	18	99.2
4	120×130×260	20	98.97
				5	120×130×260	20	98.97

Claims (1)

1, a kind of manufacture method of high-purity calcium oxide refractory materials comprises the steps: that raw material outfit, lime slaking become lime white, pulverizing, batch mixing, moulding, sintering, preventing hydration to handle, and is characterized in that:

(1) proportion of raw materials (weight %) is: lime 80-95%, anhydrous binder 5-20%;

(2) anhydrous binder be in synthetic glass acetone, gasoline paraffin or the dehydrated alcohol calcium oxide mud any;

(3) raw material lime is removed surface inclusion with physical method, and after being digested to lime white, filters;

(4) waste base is dried, is pressed into to lime white after filtering again;

(5) waste base is at calcining kiln roasting grog, and calcining temperature is 1450-1750 ℃, calcination time 10-36 hour;

(6) grog after the calcining adds in the mixer in the lump with anhydrous binder and to mix after crushed, makes compound, and as required, compound is made the parison of different shapes and specification;

(7) parison carries out sintering in moistureproof calcining furnace, and sintering temperature is 1400-1700 ℃, time 3-25 hour;