Rice Wine

November 12, 1996

Two Vincent CP-10 presses are being commissioned in Taichung, the third largest city in Taiwan. These units are at the new rice winery of the Taiwan Tobacco & Wine Monopoly Bureau.

The Bureau had previously purchased two VP-12's in 1988. They were selected to dewater rice dregs prior to delivery to local farmers for animal feed. One of the machines is in the old downtown Taichung winery that is being phased out. The second unit is lost somewhere in the group's eight wineries.

The rice dregs are a waste product resulting from the fermentation of rice. The liquor produced is called rice wine, and it is sold at 37 proof. It is used for cooking purposes, especially with chicken. The taste is bitter, and only the island's aborigine people are known to drink it.

Another product to be made at the new brewery is yellow wine. It too is made from rice, but by a process that makes it more drinkable.

Popepack Contrashear rotating drum style screens from New Zealand will be used on the rice mash ahead of the Vincent presses. These are expected to concentrate the mash inbound at 5% - 10% solids into the 10% to 20% range. A 2.8 meter headbox will be mounted at the inlet of the press. This will improve throughput and dewatering.

The 1988 presses were sold with a guarantee of 60% press cake moisture. A supervisor at the brewery told us that his has tested at 55%. For reasons that are not clear, 68% moisture was specified for the new presses.

A Ponndorf steam dryer will be used to dry the press cake from the Vincent presses. It has a rotating drum about 30' long, of stainless steel construction. The end product will have approximately 12% moisture content.

The new plant has an anaerobic digester installed in which the press liquor will be processed to produce methane. In the United States Anheuser-Busch has six breweries with this system. They report that the methane is capable of supplying 10% to 15% of the brewery's fuel needs. In Taiwan the intent is to flare the methane.

Anaerobic digestion is ideal for the press liquor because of the nature of the organic material it contains. BOD (Biological Oxygen Demand) concentrations of 1,000 milligrams per liter (mg/l) to 5,000 are common, compared with 150 to 200 in normal municipal wastewater.

The press liquor digestion system came into usage in the 1970's. Currently more than two hundred plants around the world, thirty-five of which are breweries, use the process. The six at Anheuser-Busch cost $150,000,000 and save about $30,000,000 per year in fuel and wastewater treatment costs.

A filter press will be used to dewater the sludge from the press liquor digester.

Issue 52