Rotary bed-type electric furnace

Patent metadata

Field	Value
Publication number	US-2020158434-A1
Application number	US-202016743387-A
Country	US
Kind code	A1
Filing date	Jan 15, 2020
Priority date	Jul 21, 2017
Publication date	May 21, 2020
Grant date	—

Abstract

A rotary bed-type electric furnace includes a rotary bed configured to carry material, and a rotator configured to rotate the rotary bed so that material carried on the rotary bed passes through peripheral zones of the rotary bed-type electric furnace. The peripheral zones include a feeding zone configured to receive material on the rotary bed, a drying zone configured to dry and heat material by means of electrical energy, a heating zone configured to heat material by means of electrical energy, a cooling zone configured to lower the temperature of the material and configured to release gases from the material, and a discharging zone configured to discharge material from the rotary bed of the furnace.

First claim

1 .- 19 . (canceled)

20 . A rotary bed-type electric furnace, comprising:
a rotary bed configured to carry material, and a rotator configured to rotate the rotary bed so that material carried on the rotary bed passes through peripheral zones of the rotary bed-type electric furnace, wherein the peripheral zones comprise: a feeding zone configured to receive material on the rotary bed of the rotary bed-type electric furnace, a drying zone configured to receive material from the feeding zone and configured to dry and heat material by means of electrical energy to a temperature between 50 and 300° C., a heating zone configured to receive material from the drying zone and configured to heat material by means of electrical energy to a temperature between 300 and 700° C., a cooling zone configured to receive material from the heating zone and configured lower the temperature of the material and configured to release gases from the material, and a discharging zone configured to receive material from the cooling zone and configured to discharge material from the rotary bed of the furnace, the drying zone being covered by a first section hood configured to prevent gases from escaping from the drying zone, the heating zone being covered by a second hood section configured to prevent gases from escaping from the heating zone, the cooling zone being covered by a fourth hood section configured to prevent gases from escaping from the cooling zone, a first curtain arrangement between the feeding zone and the drying zone to prevent exhaust gases from escaping from the furnace between the feeding zone and the drying zone, and a second curtain arrangement between the cooling zone and the discharging zone to prevent exhaust gases from escaping from the furnace between the cooling zone and the discharging zone.

21 . The rotary bed-type electric furnace according to claim 20 , wherein the rotator is configured to rotate the rotary bed at a rotating speed that is steplessly adjustable.

22 . The rotary bed-type electric furnace according to claim 20 , wherein the drying zone is thermally insulated with insulation.

23 . The rotary bed-type electric furnace according to claim 20 , wherein the heating zone is thermally insulated with insulation.

24 . The rotary bed-type electric furnace according to claim 20 , wherein the drying zone is provided with first exhaust ducts configured to lead vaporized matter formed in connection with the drying of the material carried on the rotary bed from the drying zone.

25 . The rotary bed-type electric furnace according claim 20 , wherein the heating zone is provided with an oxygen containing gas feeding system configured to feed oxygen containing gas into the heating zone.

26 . The rotary bed-type electric furnace according to claim 20 , wherein the heating zone is provided with second exhaust gas ducts configured to lead exhaust gas formed in connection with the heating of the material carried on the rotary bed from the heating zone.

27 . The rotary bed-type electric furnace according claim 20 , wherein the cooling zone is provided with third exhaust gas ducts configured to lead exhaust gas formed in connection with the cooling of the material carried on the rotary bed from the cooling zone.

28 . The rotary bed-type electric furnace according to claim 20 , wherein the discharging zone comprises discharging means comprising a knife, a brush or a scraper configured to remove material from the rotary bed.

29 . The rotary bed-type electric furnace according to claim 20 , wherein the discharging zone comprises discharging means comprising a vacuum arrangement configured to remove material from the rotary bed.

30 . The rotary bed-type electric furnace according to claim 20 , wherein the feeding zone comprises a feeding arrangement provided with an elongated material feeding aperture extending transversely above the rotary bed.

31 . The rotary bed-type electric furnace according to claim 20 , wherein:
the heating zone comprises a combustion section at a downstream end of the heating zone, and the combustion section of the heating zone being configured to combust material in the presence of oxygen containing gas.

32 . The rotary bed-type electric furnace according to claim 20 , further comprising treating carbonaceous material.

33 . A method of employing a rotary bed-type electric furnace according to claim 20 , comprising the steps of:
utilizing the rotary bed-type electric furnace to treat anode slime.

Assignees

• Outotec Finland Oy

Inventors

• Halkola Jari
• Kurki Seija
• Lillkung Kristian

Classifications

• C22B5/10

  by solid carbonaceous reducing agents · CPC title

• C21B13/105

  Rotary hearth-type furnaces · CPC title

• C21B13/12

  in electric furnaces · CPC title

• F27B9/16 Primary

  the charge moving in a circular or arcuate path · CPC title

• F27B9/062 Primary

  electrically heated · CPC title