Device and method of iron powder cold-pressing reduction

Abstract

The invention discloses a device and method of an iron powder cold-pressing reduction, and relates to the technical field of reduction iron production. A batching system is used for proportioning iron powder and a binding agent according to a ratio for the batching, a forced mixing system is used for uniformly mixing the batched iron powder with the binding agent, a double-roller ball press is used for pressing the uniformly mixed iron powder and the binding agent into cold-pressed pellets, a chain plate drying machine is used for carrying out drying and preheating on the cold-pressed pellets, a heating rotary kiln is used for carrying out heating sintering on the cold-pressed pellets which are dried and preheated, a swing screen is used for screening the cold-pressed pellets which are heated and sintered, a reducing agent injection system is used for spraying a reducing agent into a reduction rotary kiln, the reduction rotary kiln is used for reducing the cold-pressed pellets, a heat source of the heating rotary kiln comes from the high-temperature tail gas of the reduction rotary kiln, a heating burner is installed at a kiln head of the heating rotary kiln, and when the heat provided by the high-temperature tail gas is insufficient, the heating burner can heat the cold-pressed pellets. The method and the method have the advantages that the productivity can be improved, the normal operation of production can be ensured, and the investment cost is low.

Description

Technical field [0001] The invention relates to the technical field of reduced iron production, in particular to an iron powder cold-pressing reduction device and method. Background technique [0002] The existing reduced iron production process is a one-step chain grate rotary kiln reduction process, using such as image 3 The one-step chain grate rotary kiln reduction device shown is the process of directly producing reduced iron with iron powder. First, the iron powder and the binder are mixed in a certain proportion through the batching system 1, and the iron powder and the binder are mixed through the forced mixing system 2. After the binder is evenly stirred, it is granulated with the ball-forming plate 9 (also known as the disc granulator), and the iron powder is continuously sprayed with water in the ball-forming plate 9, and the iron powder is rolled in the ball-forming plate 9 to form 10mm-15mm Round ball. The formed balls are screened by the screening system 10, and th...

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Problems solved by technology

[0003] The existing one-step grate machine rotary kiln reduction process uses a ball-forming disc (also known as a disc granulator) to granulate. Iron powder balls have no strength after drying, and an expensive chain grate machine must be used to dry and roast the pellets. , the sintering temperature is required to be above 1150°C, and the grate plate of the grate requires heat-resistant steel that can withstand high temperatures of 1000°C, which requires a large investment. The pellets directly enter the reduction rotary kiln for reduction. If the hot air entering the grate machine cannot reach the high temperature (1150°C) required by the process, or the amount of hot air is insufficient, the pellets sintered by the chain grate machine will have no strength. After entering the reduction rotary kiln It will turn into powder, which will cause ring formation in the reduction rotary kiln, affecting production capacity and increasing equipment load

Due to the series operation of the grate machine and the reduction rotary kiln air circuit, the mutual influence, the grate machine has no means of temperature adjustment, and the heat balance is difficult to establish. A production line often takes more than one year from the start of production to normal production, which wastes time, manpower and financial resources.

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