Deactivation of sewage sludge by wet oxidation (WO) using the LOPROX process: A complete wastewater plant WO system with an analysis of wet oxidation products

The LOPROX process is a well-known and established wet oxidation process well suited for the treatment of industrial wastewater. Several plants are now in operation for processing the high levels of organic contaminants found in the wastewater which is produced by the chemical and pharmaceutical industries. This process was developed by Bayer AG and patented in 1977 with Bertrams AG acquiring the exclusive marketing rights in 1992. The LOPROX process operates catalytically in an acidic environment using oxygen fed into it. The conditions for the reaction (φ<225°C, pH<4, p<6 MPa) ensure that low-cost materials can be used and also allow the material to have a lower consistency than other thermal wet oxidation processes. This can significantly reduce investment and running costs. Although the moderate reaction conditions cannot bring about full oxidation of the material in the wastewater, they do allow the material to be broken down into smaller molecules. These can then be quickly and easily treated biologically at a later stage. The process is therefore normally used for partial stream treatment of wastewater containing high levels of organic contaminants and other material that can only be broken down biologically with difficulty. The process is an attractive alternative to other methods of organic sludge disposal. Initial laboratory trials on decomposition by wet oxidation were very encouraging. They indicated that the process might also be used in the decomposition of sludge (sewage sludge).; The LOPROX process is an established wet oxidation process well suited for the treatment of industrial wastewater. It operates catalytically in an acidic environment using oxygen fed into the system. The reaction conditions ensure low investment and running costs. The LOPROX process is an attractive alternative to other methods of organic sludge disposal. It can also be used in the decomposition of sewage sludge.