Method and apparatus for reducing volatile content of sewage sludge and other feed materials

US5263267A · kind A · utility

Assignee

• JUDCO MANUFACTURING, INC. · US

Inventors

• Thomas E. Buttner · Rancho Palos Verdes, US
• Christopher A. Mc.Clure · Los Angeles, US
• H. Judson Buttner, deceased · Beaverton, US
• James G. McCain · Lomita, US
• Arnold B. Nordstrom · Fallbrook, US
• R. Leon Williams · Eugene, US

Key dates

• Filing date: Mar 20, 1989
• Grant date: Nov 23, 1993
• Expiry date: Mar 20, 2009

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F26B17/20
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Apparatus for the drying of sludges and other fouling feed materials. A rotary screw type indirect heat exchanger is provided having at least one screw member. The screw member includes a helical-shaped flight having a helix angle of about 10 degrees or less and a surface roughness of about 63 micro-inches or less. Means are provided for rotating and heating the screw member and for spreading feed material onto the screw member. The apparatus operates at heat transfer rates and for a time period sufficient to reduce the moisture content of the feed material without requiring mechanical cleaning of feed material foulants from the screw member.