Beschreibung:
<jats:p>The costs of different types of aerobic, anaerobic and combined wastewater treatment systems are compared in this study. The assumed BOD or COD-loads from typical forest industry processes form the basis of comparison. General cost curves for various waste treatment processes and some case examples are also presented.</jats:p>
<jats:p>In the calculations it is assumed that the wastewater is treated to the same effluent quality by using activated sludge, modified activated sludge and combination of anaerobic-aerobic treatment process. In anaerobic-aerobic systems different types of combinations are analyzed. Investment, running and annual costs have been evaluated for each system.</jats:p>
<jats:p>The study shows that selection of the method or combination of methods must always be made case by case. It has been found out that in some cases the anaerobic-aerobic process combination is economically competitive. Competitiveness will increase if biogas can be utilized and a moderate price could be calculated for it. In some cases activated sludge, and especially aerated lagoon processes, has a disadvantage of requiring larger treatment spaces. Poor soil conditions and long distances to lead effluent may significantly increase the cost of these aerobic treatment methods.</jats:p>