Abstract: A system is disclosed for retrieving a mist of sulfurous acid and creating sulfurous acid from residual sulfur dioxide gas originating from an exhaust of a sulfurous acid generator. In one embodiment, such a system includes a sulfurous acid generator to output sulfurous acid, in a primary stream, and exhaust comprising a mist of sulfurous acid and sulfur dioxide gas. A recovery system is connected to the sulfurous acid generator to receive the exhaust and substantially remove the mist and the sulfur dioxide gas. The recovery system is further structured to pass the exhaust to apertures therein sized to separate the mist from the exhaust, wet itself with the liquid of the mist, and capture the sulfur dioxide gas with the liquid to substantially remove them both from the exhaust.

Abstract: A generator to provide sulfurous acid on demand and fail-safe operation includes a hopper to provide a supply of sulfur, and a burner connected to the hopper to receive the sulfur and combust it to produce sulfur dioxide gas. An inlet passes air from the environment into the burner. A channel is connected to the sulfur burner to receive the sulfur dioxide. An eductor, connected to a water supply, draws the sulfur dioxide through the channel. The generator includes a safety system to substantially inhibit discharge to the environment products of combustion that are deemed objectionable, in the event of an interruption of the water supply or shut down of the sulfurous acid generator.

Abstract: The invention relates to a method for making a dimensionally stable wood-thermoplastic composite material composed of a wood component and a thermoplastic component comprising the steps of forming a wood-thermoplastic mass at a temperature above the melting temperature of the thermoplastic component. The mass is then passed through a converging die to form a shaped extrudate profile having a cross sectional shape wherein at least a part of the converging die is maintained at a substantially higher temperature than that of the mass. The profile is then fed through a low friction thermally insulating land section, the land section having the substantially the same cross sectional shape as the exit end of the converging die. The profile is then quenched in a non-oxidizing environment to form a substantially dimensionally stable outer shell around the profile, the shell having a temperature below the melting temperature of the thermoplastic component.

Abstract: The invention relates to a method for making a dimensionally stable wood-thermoplastic composite material composed of a wood component and a thermoplastic component comprising the steps of forming a wood-thermoplastic mass at a temperature above the melting temperature of the thermoplastic component. The mass is then passed through a converging die to form a shaped extrudate profile having a cross sectional shape wherein at least a part of the converging die is maintained at a substantially higher temperature than that of the mass. The profile is then fed through a low friction thermally insulating land section, the land section having the substantially the same cross sectional shape as the exit end of the converging die. The profile is then quenched in a non-oxidizing environment to form a substantially dimensionally stable outer shell around the profile, the shell having a temperature below the melting temperature of the thermoplastic component.

Abstract: The invention relates to a method for making a dimensionally stable wood-thermoplastic composite material composed of a wood component and a thermoplastic component comprising the steps of forming a wood-thermoplastic mass at a temperature above the melting temperature of the thermoplastic component. The mass is then passed through a converging die to form a shaped extrudate profile having a cross sectional shape wherein at least a part of the converging die is maintained at a substantially higher temperature than that of the mass. The profile is then fed through a low friction thermally insulating land section, the land section having the substantially the same cross sectional shape as the exit end of the converging die. The profile is then quenched in a non-oxidizing environment to form a substantially dimensionally stable outer shell around the profile, the shell having a temperature below the melting temperature of the thermoplastic component.

Abstract: A method is disclosed for producing a wood-thermoplastic composite material using a high bulk density feedstock. The feedstock is formed by feeding a wood-thermoplastic mixture to a pellet mill where the bulk density thereof is increased by a significant amount. The pelletized feedstock may be stored for later formation into a finished product and may be blended as necessary to maintain product quality. The feedstock is easy to handle and transport and provides a manufacturer with a large degree of flexibility and control over the manufacturing process.