Heinrich Ebner, Anton Enenkel: Ultrafiltration process and apparatus using low hydrostatic pressure to prevent concentration polarization. Firma Heinrich Frings, Jerry Cohen, Charles Hieken, August 10, 1976: US03974068 (26 worldwide citation)

Liquids containing microorganisms, macromolecules or finely-divided solid matter in a liquid are filtration-concentrated by movement of the liquid containing such particles through an elongated tubular channel having membrane filters, as walls thereof, with flat surfaces and pore diameters between 1 ...

Heinrich Ebner, Anton Enenkel: Two stage process for the production of vinegar with high acetic acid concentration. Firma Heinrich Frings, Norbert P Holler, February 28, 1978: US04076844 (12 worldwide citation)

A novel two-stage submerged fermentation process for producing vinegar with an acetic acid concentration of more than 15% is disclosed. In the first fermentation stage, the total concentration (i.e. the sum of the alcohol and acetic acid concentrations) increases from a starting level between 12 and ...

Anton Enenkel: Control arrangement for a vinegar fermentation process. Heinrich Frings & Co KG, Norbert P Holler, September 27, 1988: US04773315 (2 worldwide citation)

A control arrangement for a two-stage submerged vinegar fermentation process for producing vinegar with a high acetic acid concentration of more than 15% is disclosed. The fermentation system includes a main fermentation tank and a secondary fermentation tank, a connecting line with a shut-off valve ...