Water quality – Wastewater treatment standards in different countries
In most developed countries, standards for wastewater treatment are continuously improving. Compared to the 1970s the effluent requirements for the most important pollutant indicators BOD, Nitrates and Phosphorus have steadily increased. For example, in the United states the clean water act from 1972 demands that all Municipal sewage treatment plants (POTW) are required to meet […]
COD (Chemical Oxygen Demand) – Indicator for water pollution
Chemical Oxygen Demand, also known as COD, accounts for the amount of oxygen consumed in a solution by chemical reactions in order to consume organic contaminants present, typically measured in milligrams per liter (mg/L). As oxygen is a fundamental element for degradation of any product, the amount of oxygen that is present and consumed in […]
Trickling filter process – Advantages in comparison to activated sludge
Trickling filters, also known as bio filters, are normally a fixed-bed, biological reactor operating in aerobic conditions. In the filter, microorganisms are attached to the inter packing material which was composed of rocks or gravel in the past and is nowadays a wide range of plastic fill media. Fill media support is placed on the […]