JPH073268Y2 - Circulation flow control valve of circulating fluidized bed type pre-reduction furnace - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a circulation amount control valve of a circulating fluidized bed type preliminary reduction furnace for smelting and reducing ferrous or non-ferrous metals.

[Conventional technology]

As seen in Japanese Patent Laid-Open No. 58-217615, a fluidized bed type pre-reduction furnace for iron or non-ferrous metal powder ores is currently being subjected to elemental research with equipment of about 10 T / D scale. FIG. 2 shows the overall structure of such a fluidized bed preliminary reduction furnace, which comprises a fluidized bed type preliminary reduction furnace reaction tower 6, a cyclone 13, a downcomer 12 and a regulating valve 1.

The powdery ore is reduced while flowing and circulating in a preliminary reduction furnace composed of these elements. To control the circulation amount of the powdery ore, a gas type regulating valve 1 having a cylindrical shape as shown in FIG. 3 is conventionally used, and gas supplied by a gas supply pipe 3 is blown from a gas blowing port 2 at the bottom, The ore circulation rate is controlled by adjusting the blow rate.

The operation is as follows. The ore that entered the adjusting valve 1 from the ore introducing pipe 4 on the inlet side of the adjusting valve 1 for adjusting the ore circulation amount is
Stop near entry point 7. The gas blown from the gas inlet 2 (for example, N ₂ gas raises the level of the ore in the regulating valve in a fluidized (bubbling) state, overflows the ore discharge point 8 and overflows the ore conduit 5 on the regulating valve outlet side).
It is supplied to the pre-reduction furnace reaction tower 6 by gravity flow due to gravity.

The problem with this device is that the level difference (dimension a) between the introduction point 7 and the discharge point 8 of the regulating valve 1 is constant, and the supply amount of the granular ore is changed only by the gas injection amount. That is.

[Problems to be solved by the device]

With the conventional gas regulating valve as shown in Fig. 3, it is possible to control the circulation amount of ore of a certain limited brand or particle size, but if the brand or particle size of the ore changes during operation, the gas blown in will change. There is a problem that it may not be possible to control the circulation amount of ore only by adjusting the flow rate.

The present invention solves the above problems by using all kinds of ores,
It is an object of the present invention to provide a regulating valve capable of changing the circulating amount depending on the particle size.

[Means for Solving the Problems]

The present invention is a regulating valve for regulating the circulating amount of powdered ore in a circulating fluidized bed type preliminary reduction furnace, which comprises an inlet and an outlet on the body of a standing cylinder, and the inlet In the powdery material circulation amount control valve which is installed at a position higher than the side port and has a gas flow rate control gas inlet at the bottom, this outlet port is made into a vertically long long hole, and it is inside this standing cylinder. A circulating fluidized bed type pre-reduction furnace in which a vertically movable inner cylinder is fitted and has a small-diameter opening facing the elongated hole and a vertically long opening facing the inlet port. This is a circulation amount control valve.

[Action]

In order to be able to change the level (dimension a) of the introduction point 7 and the discharge point 8 in FIG. 3, an apparatus as shown in FIG. 1 was devised.

The structure and operation of the regulating valve of the present invention will be described below with reference to FIG. The outlet of the powdery ore conduit 10 on the outlet side of the regulating valve 1 is connected to the conduit 10 by forming a long hole 21 that is vertically long. On the other hand, an inner cylinder 9 having an open bottom is provided on the inner circumference of the adjusting valve 1 so that it can be vertically moved up and down by a cylinder or the like via an elevating shaft 11. The inner cylinder 9 is provided with an opening 22 facing the elongated hole 21 of the outlet side and having a predetermined diameter smaller than this elongated hole. In the example of FIG. 1, an internal conduit 15 is connected to the opening 22 on the outlet side of the cylinder, and the internal conduit 15 projects into the conduit 10. This internal conduit 15 may optionally be omitted. Further, the opening on the inlet side of the powdery ore, which the inner cylinder 9 communicates with the conduit 4, is an opening 23 vertically longer than the opening of the conduit 4. As described above, the adjusting valve of the present invention has a double structure.

The inner cylinder 9 is moved up and down by an elevating device 11 and fixed at an appropriate position (level) to set an appropriate drop size a. The fixed position is determined by the ore brand and grain size. The ore circulation amount during the operation with the dimension a properly fixed is controlled by the gas injection amount from the gas injection port 2.

〔Example〕

 An embodiment is shown in FIGS. 1 and 2.

The powdery ore supplied to the pre-reduction furnace reaction tower 6 is fluidized and raised by the reducing gas supplied from the gas supply port 14 and is guided to the cyclone 13 together with the reducing gas, and the ore and the reducing gas are separated by the cyclone 13. . The ore is once stopped in the downcomer 12 and enters the regulating valve 1 via the conduit 4. The regulating valve 1 of the present invention is adjusted according to the brand and grain size of the ore, fixed at the optimum position, and the gas injection amount is adjusted to control the ore circulation amount.

In this way, a variety of ore brands with different properties, such as Carol Lake, MBR-PF, MBR-B, Mount Newman, ore brands with a wide variety of particle sizes and other characteristics, can be switched during continuous operation. .

[Effect of device]

According to the present invention, different ores can be continuously pre-reduced, and the operation rate of the pre-reduction furnace can be increased.
In addition, the range of operation can be widened, and this device can be effectively used in searching for the point of stable operation.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the structure of a regulating valve according to an embodiment of the present invention, FIG. 2 is a skeleton diagram of the entire preliminary reduction device, and FIG.
The figure is a vertical cross-sectional view showing the structure of a conventional ore regulating valve for regulating the ore circulation amount. 1 ... Adjusting valve, 2 ... Gas injection port 3 ... Gas supply pipe 4 ... Ore conduit (adjusting valve inlet side) 5 ... Ore conduit (adjusting valve outlet side) 6 ... Preliminary reduction reactor reaction tower 7 ... … Ore introduction point to the adjustment valve 8 …… Ore discharge point from the adjustment valve 9 …… Inner cylinder, 10 …… Adjustment valve outlet side conduit 11 …… Inner cylinder lifting device, 12 …… Downcomer 13 …… Cyclone, 14 ...... Gas supply port 15 …… Internal conduit, 21 …… Long hole 22 …… Opening, 23 …… Opening

Claims (1)

[Scope of utility model registration request] 1. A regulating valve for regulating the circulation amount of powdery ore in a circulating fluidized bed type preliminary reduction furnace, comprising an inlet side port and an outlet side port in the body of a standing cylinder, and the outlet side port. In a circulating control valve for powdered raw material, which is provided at a position higher than the inlet port and has a gas inlet port for adjusting the flow rate at the bottom, the outlet port has a vertically long elongated hole and the inside of the standing cylinder. A circulating fluidized bed type pre-reduction is characterized in that a vertically movable inner cylinder is fitted and inserted, and the inner cylinder has a small-diameter opening facing the long hole and a vertically long opening facing the inlet side opening. Recirculation amount control valve for the furnace.