EFFECT OF IONIC EXCHANGER ADDITION ON THE ANAEROBIC-DIGESTION OF COW MANURE

The long retention time required for cow manure digestion could be att ributed to the presence of complex organic compounds but also, to the high concentration of ammonia (NH4 + Plus free NH3) that affects the a naerobic digestion. Both problems could be ameliorated by the utilizat ion of ionic exchanger supports. The subject of the present work was t he evaluation of the natural zeolite as ionic exchanger. It was observ ed that the digester with zeolite addition had the best behaviour duri ng the experiments while inhibition of anaerobic degradation was obtai ned in a control digester with suspended biomass.