Agronomy journal, Vol. 73 No. 6, 2011.
Preliminary communication
ECOLOGICAL CARE OF ACTIVE SLUDGE FROM THE FOOD INDUSTRY WASTE WATER TREATMENT
Daniela Nekić Dvorski
; Starogradska 20/1, Koprivnica, Hrvatska
Abstract
Active sludge evolves as a by-product of biological treatment of waste water in the scrubber and it demands special technology of treatment and stabilization. With all technological treatments, active sludge can be turned into a form that is accepted by the environment, but the treatments are financially demanding. With the help of advanced technologies waste sludge is composted and can be used in agriculture. Before using sludge on agricultural land extended laboratory analyses are done. The analyses determine the number of harmful substances and microorganisms strictly according to regulations. The stabilization of sludge is necessary for destroying pathogen microorganisms which can be found in sludge. By that the nutrients in composted sludge are preserved. The composted sludge can be used in agriculture as a useful material for increasing the fertility of soil. With that aim the research was carried out with three kinds of sludge. Samples of sludge from the scrubbers of waste waters from "Danica", brew eries "Carlsberg" and "Kvasac d.o.o. Zagreb" were used as the main raw material for the experiment. The samples of sludge were mixed with straw and zeolite, which are known for their positive characteristics and effect on soil. The values of temperature, pH and dry matter were analysed in the laboratory to determine the activity of microorganisms in sludge and
suitability of sludge as a material for composting. The first experiment was carried out in the beginning of February from the scrubbers of "Danica". The results show a considerable activity of microogranisms in sludge. The experiment was repeated with samples from the brew eries "Carlsberg" and "Kvasac" during the summer. The activity of microorganisms was bigger than in the first experiment.
Keywords
active sludge; waste water; composting; ecology
Hrčak ID:
82658
URI
Publication date:
25.5.2012.
Visits: 4.158 *