JPS59128209A - Method and apparatus for manufacturing calcium carbide - Google Patents

Abstract

PURPOSE:To obtain industrially CaC2 without extreme local overheating, melting loss of furnace wall and attachments nor oxidation decomposition of produced CaC2, by carrying out the heating of a mixture of quick lime and carbonaceous substance by combustion flame of CO and O2 in the manufacture of CaC2 by an oxygen process. CONSTITUTION:A mixture of starting materials such as pulverized quick lime, coal or cokes having uniform grain sizes is charged to the upper part of a furnace 3 from a storage tank 1 and to a preheating chamber 4 by a definite quantity portionwise by a conveyer 2 and piled up on a perforated partition board 5. The mixture is preheated by heated gas of a combustion chamber 6, sent to a furnace bottom by a definite quantity portionwise in accordance with the opening degree of a horizontal door 7, and pushed out to the chamber 6 by keeping an inclined surface 9 having an angle of repose. On the other hand, CO compressed by a compressor 10 is mixed with pure O2 from a supply pipe 12 in a mixer 11 to be burnt by a burner 13, and the starting material is sintered by a combustion flame and slid down to a melting crucible 14. The melting mixture consisting essentially of CaC2 and a slag are respectively taken out from outlets 15, 16. The combustion gas and a reaction gas generated from the surface 9 and the crucible 14 are sent to the chamber 4, brought into reaction with carbon, and CO2 is reduced to CO. Thus, the control of heating temp. of the starting material is carried out accurately.

Description

[Detailed Description of the Invention] This invention produces calcium carbide using the combustion heat of carbon and pure oxygen (meaning oxygen that is not oxygen in the air, the same applies hereinafter) without relying on electricity! ! ! This paper relates to improvements in the method for producing calcium carbide (hereinafter referred to as the oxygen method for producing calcium carbide) and equipment.

The oxygen method calcium carbide production method is extremely advantageous compared to the electric power method, as the carbon and pure oxygen consumed in the process of fervor are recovered in their entirety as pure anti-oxidized carbon, which is important as a raw material for the chemical industry. Although many studies and proposals have been made in the past, it has not yet been implemented industrially. The reason for this is that conventional equipment of this type injects pure oxygen directly into a mixture of quicklime and carbonaceous material, causing the carbonaceous material in the mixture to be directly combusted by the oxygen. Complete combustion of carbon with pure oxygen occurs, locally reaching r = several thousand degrees Celsius, evaporation of oxidizing power, thermal decomposition, oxidative decomposition, etc. occur, the formation of calcium carbide is hindered, and the furnace The walls and oxygen blowing pipes are melted and damaged, and the accumulated raw materials reach the bottom of the furnace, which has become a cavity due to combustion and reaction.
This was because crystal disturbances such as collapse occurred, making stable operation almost impossible. The present invention aims to improve the above-mentioned deficiencies. The method and apparatus of the present invention will be explained in detail below.

The gist of the method of the present invention is to project a combustion flame of carbon monoxide and pure oxygen generated by a reaction onto a slope where a mixture of particulate quicklime and coal or coke is piled up while maintaining a natural angle of repose. The surface layer of the slope is heated and sintered to partially cause the calcium carbide-upper solidification reaction, and the back pressure of the continuously supplied raw material causes the surface layer to slide down into the crucible.・Put it into a eutectic mixture consisting of carbide and calcium oxide, complete the reaction as a solid-liquid reaction, and obtain it as molten calcium carbide with a purity of about 80%.The combustion gas is regenerated by reaction with carbon. In this method, the raw material is preheated together with a reaction gas that turns into carbon monoxide and produces calcium carbide, and then a portion of the raw material is burned with oxygen again to be subjected to a reaction.

According to the method of the present invention, since the heat source is a combustion flame of carbon monoxide and pure oxygen, the temperature of the flame can be precisely adjusted by adjusting the amount of oxygen by adjusting the burner. This method does not cause evaporation or sublimation of the raw calcium oxide or carbon or thermal decomposition of the produced calcium carbide due to extreme local overheating, and will not melt or damage the furnace walls or accessories. do not have. or,
Oxidative decomposition of calcium carbide produced by oxygen can also be prevented. In addition, in the method of the present invention, since the reaction section and the raw material preheating section are clearly separated, unlike the conventional method, the pressure of the raw material accumulated in the upper part for the purpose of preheating prevents the reaction in the lower part. There will be no confusion such as parts being crushed and collapsing.

In addition, the reaction rate of calcium carbide production at around 2000°C is extremely slow due to the in-phase reaction, but in the method of the present invention, the charcoal and quicklime are heated to form a solid 4I4 state with Hyε 1-hat? 'After the carbonaceous material that is easy to dM on the J melt is hardened into quicklime, a back H- is added to the slope,
The surface layer is slid down into a crucible in which a eutectic mixture of calcium oxide and lucium carbide is melted at 1900-2000'C, and the remaining calcium oxide is converted into a eutectic mixture with calcium carbide at a relatively low temperature. By melting and increasing the reaction rate by making the reaction with carbon a solid-liquid reaction, and by releasing the generated carbon monoxide out of the reaction system as bubbles in the liquid, the equilibrium of calcium carbide production is balanced. There is. The combustion generated gas is a mixed gas of carbon dioxide gas and carbon monoxide.
20 (contact with carbon at a high temperature of 100C, all becomes carbon monoxide powder, and the raw material is heated (/heated to reduce θ, jX,
A part of it is used for combustion with oxygen as IJ fuel, and the rest is collected as a by-product. Next, the method and apparatus of the present invention will be specifically explained with reference to figures and examples.

The figure is a schematic diagram for explaining the method and apparatus of the present invention. A homogeneous mixture of quicklime and anthracite or coke in a fixed proportion, which has been crushed in advance and has a uniform particle size, is supplied from the raw material storage 1 to the preheating section 4 from the upper part of the furnace body 3 via a screw conveyor 2. is piled up above the perforated partition plate 5, preheated by hot gas from the combustion chamber 6, and fed into the hearth bottom 8 in portions according to the opening degree of the horizontal opening/closing corridor 7.
It is pushed out into the combustion chamber 6 while maintaining the angle of repose inclined surface 9. On the other hand, the dredged carbon silica fed under pressure by the gas feeder 10 is mixed with pure oxygen fed from the oxygen supply pipe 12 in the mixer 11, and is combusted in the combustor 13, so that the combustion flame is spread over the slope of the raw material. Projected to 9. The quicklime and anthracite coal or coke particles on the inclined surface 9 are heated, and the quicklime particles and the anthracite coal or coke particles are sintered by a solid reaction, and pushed by the pressure of the raw material, they slide down into the molten collar 14. The reaction is completed by a solid elutriation phase reaction, and the resulting molten mixture of about 80% calcium carbide and about 20% quicklime is calcium carbide.
Slap that flows out from the carbide outlet 15 and floats to the liquid surface is discharged from the slap outlet 16. combustion gas and 1
The reaction gas generated from the 1a'I diagonal iMi 9 and the bath melting collar 14 enters the preheated ¥4 through the 1'' hole of the cutting plate 5, and the carbon dioxide in the gas is absorbed into the raw material under marrow temperature. It comes into contact with carbon and becomes carbon monoxide, which preheats the raw material and releases upper gas
7, the -gli is sent to a mixer 11 by a pressure feeder 0, mixed with oxygen, combusted in a combustor 3, and again provided to the heat gap for the calcium carbide production reaction. 1900'C or higher in the furnace,
In places where strength is required, RIJ perforated partition plate 5, combustion chamber 6, horizontal opening/closing base 7, furnace bottom 8, bath melting chamber 14, calcium carbide outlet O 15, and slag outlet 16, the particulate matter is calcium oxide. Stabilized zirconia is used, and the rest is made of AA material with a hole size of 1ljJ depending on the temperature. Next, an example will be described.

An example of the method of the present invention using an experimental apparatus for preparing approximately 80% pure +W calcium carbide is as follows. 1 piece of quicklime with average particle size 1 piece of anthracite with the same particle size
．． Uniform mixture of 94 weight per hour 9 to 114.5 #
] and operated as described above to form the raw material inclined surface 9, while the hourly s5. The carbon monoxide xN,,z is combusted in the fuel standard 6 using 42.5Ni per hour of pure acid pumped through the pipe 12, and the flame generated is projected onto the slope. As a result of operating as described, 41.7 kg of calcium carbide with 82% purity was obtained from the calcium carbide outlet 15, and 98% pure calcium carbide was obtained from the upper gas outlet 17 at 200°C with carbon monoxide. 182.3 Nm3 was emitted per hour, and 85.3 Nm3 per hour was emitted. ．． 77% of lN is used for combustion with oxygen as reaction heat, remaining 97.2N/hour, IF
98% pure carbon monoxide was obtained as a by-product.

Converting the above to the consumption per ton of calcium carbide with 82% purity, 935.3 to 9 of quicklime, 9 to 1810.51' of anthracite, 5 Ni of acid] are consumed, and monoxide of 2332.1N of Carbon is produced as a by-product, and this is compared to the IQ of the conventional method, per 1 ton of 82% calcium carbide, 1000 kg of quicklime, and 2 Q of anthracite.
OOK9, oxygen 1100N771! consumes 230o
It was recognized that the efficiency was much higher than that of generating Nm3 carbon monoxide, and in addition, stable operation for a long period of time was obtained in this experiment without the above-mentioned disturbance due to local overheating.

It goes without saying that coke can be used instead of anthracite as the carbon material.

[Brief explanation of drawings]

The figure is a schematic diagram for explaining the method and apparatus of the present invention, where l is a raw material storage tank, 2 is a screw conveyor, 3 is a furnace body, 4 is a preheating section, 5 is a hole partition plate, and 6 is a combustion chamber. , 7 is a horizontal opening/closing valve, 8 is a furnace bottom, 9 is a slope of the angle of repose of the raw material, 10 is a gas pumper, 11 is a tempering vessel, 12 is an oxygen supply pipe, 13 is a combustor, 14 is a bath melting unit, 15 indicates a calcium carbide outlet, 6 indicates a slug outlet, and 17 indicates a gas outlet. Procedural Amendment (Voluntary) qkori Wl'lf J*Kankokesugi Kazuo 1.41 Table of 74< 1981 Patent Application No. 000
595 No. 2, Benefits of the invention, Method and apparatus for producing nocolsium carbide 3. Name and address to be amended: 15 Koganemachi, Niigata City Specification 5, Contents of amendment

Claims (3)

[Claims] (1) A method of producing lucium carbide and carbon monoxide by heating a mixture of quicklime and coal or coke with a combustion flame of carbon monoxide and oxygen. (2) heating a mixture of quicklime and coal or coke with a combustion flame of carbon monoxide and oxygen to produce calcium carbide and carbon monoxide, after the carbon oxide preheats the quicklime and coal or coke; An apparatus for producing calcium carbide, characterized in that a part of it is burned again with oxygen to heat a mixture of quicklime and coal or coke. (3) The apparatus according to claim (2), characterized in that a mixture of particulate quicklime and coal or coke is naturally deposited, formed while maintaining an angle of repose, and melted in a bath.