Comparison and evaluation of current and innovative technologies for industrial wastewater treatment

Industrial wastewater discharges and their treatment processes are of great interest for environmental pollution control and management. During the last decade innovative technologies and techniques have been assessed and applied due to the enforcement of discharge regulations. The increasing pressure to comply with the wastewater discharge permits has led to the construction of new and upgrading treatment works and to cost-effective and application-specific treatment processes. Existing biotreatment processes have proven in many cases inappropriate for degrading and removing organic matter in high concentrations. The main difficulties that usually appear in conventional processing can be overcome by changes in the microbial community during treatment. One of the most problematic areas in biotreatment processes is the biodegradation of fats, oils and grease. These components in wastewater streams require specific technology in order to produce a low-organic loading effluent. The problem increases because of the fact that industrial units and operators are reluctant of altering the already installed processes. Industries are more likely to construct typical treatment works despite the fact that they might have essential differences in their production procedures and consequently in their discharges. In the Prefecture of Thessaloniki, a research took place concerning the industrial units which operate during the last five years, according to official data provided by local authorities. This data was processed, analyzed and categorized in order to get information on treatment works operated, their influents and effluents, organic loadings, specialized wastewaters, discharge limits, effluent receivers, e.t.c. The results and conclusions are of great importance because they provide analytical information on environmental pollution, indicate the areas that industrial operations increase, group these industries according to their installations and wastewaters. Food processing industry showed the greater increase in terms of operating units in comparison to other industrial applications. By taking into account the fact that food industries produce high-strength industrial wastewater because of their concentration in fats and oils, the study was focused on the area of biotreatment which involves the use of specific microorganisms and bacteria. Samples were collected from specific industries and laboratory and pilot work took place. The study showed that improvement in conventional biotreatment processes may be accomplished by the use of bioadditives such as enzymes and specific microorganisms.