Sewage Pretreatment

Refusals to accept certain contaminations, additional fees on highly loaded wastewaters and specific storm water fees are tools that have been set towards a sustainable water management. The big number of complicated water regulations by state and the federal government cause effects disturbing each other. A selected deregulation seems necessary. Expand…

In the course of the extension of the waste water treatment plant of Cloppenburg/Germany to 190,000 PE a 2-stage biofiltraton plant was integrated in the treatment process. By the analytical program carried out in the course of the demonstration Project on biofiltration sponsored by the German Umweltbundesamt, it could be proved that the 2-stage biofiltration plant effects additional COD-removal of about 60% (effluent concentration 35 mg/l) and an average final total phosphorus concentration of about 0.5 mg/l. With respect to nitrification, biofiltration proved to be a powerful process. Effluent concentrations of ammonia below 1.0 mg/l could be achieved but were not stable. Expand…

With the help of an anaerobic pre-treatment plant, the process wastewater of Lindavia Fruchtsaft AG could be purified to concentration levels of municipal wastewater in an economical and stable operation. Important factors were the reduction of COD-charge and the reduction in quantities of sludge passed on to the purification plant. The selected design of the equipment has a methane reactor designed as an UASB-reactor with a separate acidification stage. Expand…

Analysis of wastewater discharge samples from the preliminary and secondary treatment stages of a number of sewage treatment plants, and of rainwater samples, has revealed a clear correlation between solid particles in suspension and adsorbed pollutants. Purification processes have been substantially influenced by the solid particle size distribution. Expand…

On the basis of investigations using three different leachates, a process technology using a combination of chemical oxidation and secondary biological purification has been optimised to the point where energy consumption has been reduced by up to 30%, in comparison with oxidation alone. Expand…

The DESAR Concept, “Decentralised Sanitation and Reuse” is regarded as an alternative to classical water supply systems. It is based on decentralised and inexpensive system solutions which work with low specific water consumption. The focus hereby is a treatment of the material flows close to the source of origin and water re-use. Expand…

Trials conducted on an industrial scale have proceeded on a reliable and trouble-free basis, and have clearly confirmed the suitability of covered rotating biological contactor (RBC) as an option for upstream denitrification. Through the retrofitting of RBCs to existing sewage treatment plants, compliance with more stringent statutory requirements for overall nitrogen discharge concentrations can be achieved. Expand…

Wastewater storage reservoirs in Israel are frequently affected by the unwanted accumulation of high quantities of nitrites. This is caused by various factors, such as insolation, increased concentrations of ammonia and the bioavailability of iron. Investigations have shown that this problem can be solved by an increase in the active mass of nitrifying bacteria associated with the provision of darkened cultivation zones. Expand…

Bacteria contained in biologically purified wastewater will need to be removed before this water can be discharged into bathing waters with no adverse impact upon health. In the course of laboratory investigations, a process for this purpose has been tested which combines extensive disinfection, associated with the abrupt alteration of the treatment medium, and ultrasonic treatment. Expand…