초록 ▼

The present invention provides a system and method for collecting fumes from an arc furnace of the type typically used in metal foundries. The system provides an electrode hood with extended sides for improved collection of fumes from the vicinity of the electrodes. It also provides a movable spout

The present invention provides a system and method for collecting fumes from an arc furnace of the type typically used in metal foundries. The system provides an electrode hood with extended sides for improved collection of fumes from the vicinity of the electrodes. It also provides a movable spout hood for collection of fumes when metal is tapped. A combination of a tilting manifold and stationary duct are used to maintain a path for collecting fumes throughout the entire range of motion of the furnace. The stationary duct has a group of dampers that open and close as the furnace tilts. Variable position dampers may be provided at the electrode hood and furnace door. In the bag house, there is a dust containment assembly to limit the movement of the collected dust. A variable speed fan may be used with the system. One method of the invention involves determining the pressure differential upstream and downstream of the filter bag, determining the fan speed, and closing a damper downstream of the filter to clean the filter bag when the determined values for the pressure differential and fan speed match previously set values. The entire system may be controlled by a programmable logic element to maximize efficiency. Another method involves the steps of adjusting the electrode hood damper, spout hood damper and door hood damper in response to furnace conditions.

대표청구항 ▼

[ We claim:] [1.] In an electric arc furnace of the type having a spout for tapping metal and a crucible body for heating metal, the metal being tapped into a ladle by tilting the furnace so that metal flows through the spout, a system for collecting emissions during tapping comprising:a spout hood

[ We claim:] [1.] In an electric arc furnace of the type having a spout for tapping metal and a crucible body for heating metal, the metal being tapped into a ladle by tilting the furnace so that metal flows through the spout, a system for collecting emissions during tapping comprising:a spout hood including:a main spout hood having an edge around a main opening; anda support for supporting the main spout hood for movement with tilting movement of the furnace and for movement between a first collecting position whereinthe main spout hood overlies the spout and a second non-collecting position wherein the area above the spout is substantially free from obstruction;the system further including a tilting duct supported for movement with tilting movement of the furnace and the main spout hood, a stationary duct supported to be independent of tilting movement of the furnace and main spout hood and an exhaust for drawing emissions through the spout hood main opening when the main spout hood is in the first collecting position;wherein in the first collecting position the system provides a flow path for drawing emissions from the main spout hood to the tilting duct and to the stationary duct and wherein in the non-collecting position the main spout hood is disconnected from at least a part of the tilting duct.