The year 2002 was remarkable in terms of working with sweet corn canneries. Corn canners operate on a huge scale, but only for a short ten-week harvest season. Of the corn delivered to the plant, fully two thirds is waste in the form of husk and cob.

The waste, commonly called corn silage, is sold to nearby farmers as animal feed. Heaped in relatively airtight piles, the entrained oxygen is consumed. This process, a limited fermentation, is called ensilage. The result is a palatable animal feed with many months of shelf life.

The need of the corn canners is to separate free water from their waste stream. Traditionally, reciprocating baling machines have performed this function. High maintenance, constant operator attention, along with limited capacity, have been drawbacks to the equipment.

This last season the Series KP “soft squeeze” screw press proved itself well suited for the dewatering task. Seabrook in New Jersey had good results with a Model KP-16, with press cake moisture of 80% being typical.

At the same time our first Model KP-24 was being used at Lakeside’s Plainview plant. It processed a steady 70 tons per hour of waste, but dewatering was not adequate. Switching to a 50-hp drive permitted operators to increase the air pressure on the discharge door. The result was the desired dewatering.

This KP-24 has been purchased for Lakeside’s Brooten, MN plant. At the same time a 75 hp Model KP-30 has been ordered for the Plainview, MN cannery. This new machine will dewater 100 tons per hour of corncob and husk.

It is noteworthy that all of these installations involve replacement of baling machinery that is but five years old.

Three other sweet corn cannery projects took place in 2002. (a) Agriglink used a Model FF-12 Fiber Filter to remove suspended solids from their wastewater stream, addressing a pond odor problem at the Waseca, MN cannery. (b) Seneca Foods installed a Model KP-16 press to dewater sludge from their silage digester in Montgomery, MN. Biogas from this digester makes Seneca the largest gas producer in Minnesota. And (c) Del Monte ran tests in their Mendota, IL cannery where the goal was to maximize moisture removal. To our surprise, press cake moisture of 66% was achieved. The possibility of using this cake as gasifier fuel is under consideration.