Vapor Tight Screw Presses
February 18, 2002 ISSUE #125
Recently a very successful start-up of two Model VP-22 screw presses was accomplished. These machines are unusual in that they were made in vapor tight construction. The presses are being used to separate aqueous alcohol solution from pectin.
The customer is CP Kelco, formerly Copenhagen Pectin. Their factory in Denmark is the world's largest producer of pectin, a food ingredient which is extracted from dried citrus peel. The raw material, dried lime, lemon, grapefruit, and orange peel, is purchased from citrus processors around the world.
The pectin is extracted from the peel with acid followed by isopropyl alcohol (IPA) precipitation. The product goes through various wash stages before final pressing ahead of drying. Vapor tight covers contain the IPA fumes, which can be explosive.
Currently Vincent has another vapor tight press under construction. It is a VP-16 that will be used in the production of Soybean Protein Concentrate (SPC). This is a traditional application for Vincent screw presses. In the process aqueous ethanol is pressed from the soybean protein ahead of a steam dryer. The installation will be in Haifa, Israel, with start-up scheduled for later this year. (See Pressing News #24, Solvent Extraction.)
Another machine, a CP-6, is being designed for Crown Iron Works of Minneapolis. This press is proposed to be used to separate methanol solution from a material similar to pine needles. This installation will be on Prince Eduard Island, Canada.
The machines reflect safety concerns because of the alcohols that are present. Explosion proof motors are supplied. Another feature is the use of bronze fasteners to prevent sparking. Because of the potential for fire, V-belt drives cannot be used, so in-line drives are necessary. Bolted vapor tight covers are used throughout, usually with Pyrex portholes that include manually operated wipers. These design features assure compliance with safety codes.