METHOD OF CONTROLLING AN ANAEROBIC TREATMENT PROCESS

摘要

The invention relates to a method of controlling a hydrolysis step in an anaerobic treatment process for treating wastewater from the manufacture of peroxide bleached mechanical or chemi-mechanical pulp. The method involves continuously measuring the redox potential of outgoing water from the hydrolysis step and controlling the ingoing water to the hydrolysis step at demand, so that some ingoing water is directed past the hydrolysis step to a subsequent aerobic step. The method ensures that anaerobic bacteria in a methane fermentation step which is subsequent to the hydrolysis step is not killed by hydroperoxide in the wastewater emanating from the hydrolysis step, the hydroperoxide being effectively removed or reduced by the present invention.