METHOD OF RECOVERING ENERGY FROM AN ELECTRIC INDUCTION FURNACE EXHAUST GAS IN THE GASIFICATION OF FEED FUEL TO EXHAUST GAS

摘要

A method of recovering energy from an electric induction furnace exhaust gas in the gasification of feed fuel to exhaust gas. Melt of an electrically conductive material, which is disposed within electric induction furnace, is pressurized while substantially sealing the electric induction furnace to enable the build-up of a superatmospheric pressure in said furnace. A feed fuel is injected into contact with at least a portion of the melt of electrically conductive material. Exhaust gas generated at a superatmospheric pressure is withdrawn from said furnace and scrubbed and stored for subsequent use in a gas accumulator. The total calorific value of the exhaust gas from the gas accumulator that is available for use by a gas consumer device is measured and estimated. An input of feed fuel, of auxiliary gases and of heating power to the electric induction furnace is adjusted such that the estimated total calorific value of exhaust gas is kept between a pre-determined upper and a pre-determined lower threshold by using an adjustable controller unit that comprises a PD controller. A gas consumer device is fed with the exhaust gas from the accumulator independently of the blowing periods. The electric induction furnace exhaust gas is maintained under superatmospheric pressure during the blowing, withdrawing, scrubbing and storing steps without recompression.

主权项

1. A method of recovering energy from an electric induction furnace exhaust gas in the gasification of feed fuel to exhaust gas, comprising the steps of:
blowing onto a melt (1c) of an electrically conductive material disposed within the electric induction furnace (1) while substantially sealing the electric induction furnace (1) to enable the build-up of a superatmospheric pressure in the furnace (1); injecting feed fuel pre-sized to a proximate sieve size of between 0.5 and 1.5 mesh into contact with at least a portion of the melt (1c) of electrically conductive material; withdrawing exhaust gas generated at a superatmospheric pressure from said furnace (1); scrubbing the withdrawn electric induction furnace exhaust gas to a proximate temperature range above 90 degrees C. with water in an annular-gap washer (13) having a control member (12) for varying the pressure differential across a scrubbing gap and thereby controlling the pressure in said furnace (1); and piping used scrubbing water to a multiplicity of filters (4g) for cleaning used scrubbing water to derive cleaned scrubbing water wherein cleaned scrubbing water is re-circulated for re-use; storing the scrubbed electric induction furnace exhaust gas for subsequent use in a gas accumulator (11); measuring and estimating the total calorific value of exhaust gas available for use by a gas consumer device from the accumulator (11); adjusting an input of feed fuel, of auxiliary gases and of heating power to the electric induction furnace (1) such that the estimated total calorific value of exhaust gas is kept between a pre-determined upper and a pre-determined lower threshold, wherein the adjusting of feed fuel, of auxiliary gases and of heating power to the electric induction furnace (1) is provided by an adjustable controller unit (100), the adjustable controller unit (100) comprising a PD controller; feeding a gas consumer device (20, 21) with the exhaust gas from the accumulator (11) independently of the blowing periods; and maintaining the electric induction furnace exhaust gas under superatmospheric pressure during the blowing, withdrawing, scrubbing and storing steps without recompression.