JPH03183732A - Manufacture of quicklime by sintering machine - Google Patents

Abstract

PURPOSE:To exceedingly reduce the unsintering and oversintering of limestone, at the time of charging coke breeze and limestone powder to the topmost layer of a pallet in a sintering machine and executing sintering, by using a drum shoot and reducing the particle size from the upper layer part to the lower layer part. CONSTITUTION:A mixture of limestone powder and coke breeze is charged to the topmost layer of a pallet 1 in a Dwight-Lloyd sintering machine to form quicklime by heat in an ignition furnace. At this time, a drum shoot 21 is used, and the limestone in a hopper 19 is subjected to particle size segregating to regulate the particle size distribution in the height direction of a limestone layer in such a manner that the upper part has coarse one and the lower part has fine one. Then, coarse limestone is charged to the range having the most heat and fine limestone to the range having small heat.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for producing quicklime in the uppermost layer of a sintering machine pallet in a sintering process of raw material for a blast furnace using a Dwight Lloyd sintering machine. The present invention relates to a method for improving the quality and productivity of quicklime.

<Prior art> Figure 2 shows a schematic diagram of a sintering operation for blast furnace raw materials using a Dwight Lloyd sintering machine. The sintering raw material 2 cut out from the feed hopper 4 is stacked and supplied on top of the sintered material 2. The raw material 2 is ignited by the igniter f15, and the coke powder in the sintering raw material is combusted by ventilation from the main blower 14, and the sintering raw material is fired to become sintered ore. The sintered ore is crushed in a crusher 415, cooled in a cooler 6, and then classified in a sieve 117.

The product on the sieve with a particle size of 8 to 16 m is returned to the bedding hopper 3 as bedding ore 1O, and the remainder is transported to the blast furnace as product 13. On the other hand, the classified particles with a particle size of -5 am or less are returned to the mixer 8 as tlE 11 and are then transferred to the new raw material 12.
After being mixed with ore, it is returned to the feed hopper 4.

Generally, as a means to improve the air permeability of the raw material 2 on the pallet, a binder may be mixed into the raw material.
Quicklime (CaO) is commonly used as a binder.

As a method for producing this CaO at low cost, JP-A-58-
Publication No. 133331 discloses that lime (CaCOs) powder 9 is cut out from a lime hopper 19, layered on the bottommost part of the raw material 2, and caused to undergo a reaction according to the following formula (1) with the heat in the igniter 15, to form CaCO3. →CaO+ Cog+ΔH−−−−−−−
-(1) (ΔH: enthalpy difference) A method for producing quicklime powder from limestone powder has been proposed.

However, the dissociation of COl progresses gradually from the surface to the inside of limestone, so when firing limestone with a wide range of grain sizes, if you aim for firing at small grain sizes, the larger grains are often unfired, and the larger grains If tB is combined with tB, the small particle size will result in over-bottoming, which poses problems in terms of production efficiency and quality.

<Problems to be Solved by the Invention> An object of the present invention is to provide a method for producing quicklime using a sintering process with higher efficiency and higher quality than before.

<Means for Solving the Problems> In other words, the present invention provides a sintering process using a Dwight Lloyd sintering machine, in which a mixture of limestone powder and coke powder is charged into the top layer of a sintering machine pallet. When producing quicklime powder from limestone powder using heat in a furnace, the particle size distribution in the height direction of the limestone layer is controlled by a drum shade, which is used to charge coarse limestone at the top and finely at the bottom. This is the manufacturing method.

Effect> In the present invention, when charging coke powder and limestone powder to the uppermost layer on the sintering machine pallet, particle size segregation occurs in the height direction of the limestone layer by the drum shade, and the particles are separated from the upper layer to the lower layer. Since it was charged so that the particle size decreased,
Coarse-grained limestone can be charged in the 9m area where the most heat is generated, and fine-grained limestone can be charged in the area with the least amount of heat, and as a result, uncalcined limestone and excessive bottom of the mine can be significantly reduced.

A concrete configuration for performing the above charging is shown in FIG. 1. A mixture 9 of coke and limestone powder is cut out by a drum feeder 20 of a hopper 19 for limestone, and is dropped into a drum shade 21.

The coke powder and limestone powder were emulsified in a rotating drum shoe and subjected to neutralization titration with 4N hydrochloric acid for 1 hour.The amount of 4N hydrochloric acid used after 5 minutes was (d).

<Effects of the invention> In the process of charging coke powder and limestone powder to the top layer of the sintering machine pallet to form the bottom of the pit, and generating quicklime powder from the limestone powder using heat in the ignition furnace, the height of the limestone layer was reduced. Grain size distribution of limestone in direction ffi by drum shade
'J m was able to improve the productivity and quality of quicklime.

Therefore, when compared with the conventional method, it has become possible to significantly reduce costs in producing quicklime.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an apparatus for implementing the present invention, and FIG. 2 is an explanatory diagram of a sintering operation process. l...Pallet, 3...Hopper for bedding ore 4...Sintering raw material feeding hopper 5...Crusher, 7...Sieving machine, 2...Sintering raw material, 6 ...Cooler 8...Mixer 9...Mixture of limestone powder and coke powder, lO...
Bed ore, 11... Return ore, 12... New raw material, 13... Product, 14... Blower, 15... Ignition device, 19... Limestone hopper 20... Drum Feeder 21...Drum shade.

Claims (1)

[Claims] In the sintering process using a Dwight Lloyd sintering machine,
When charging a mixture of limestone powder and coke powder to the top layer of the sintering machine pallet and generating quicklime powder from the limestone powder using the heat in the ignition furnace, the particle size distribution in the height direction of the limestone layer is measured using a drum shade. A method for producing quicklime using a sintering machine, which is characterized by charging coarsely at the top and finely at the bottom.