Page 259 - Industrial Wastewater Treatment, Recycling and Reuse

Novel Technologies for the Elimination of Pollutants 233

Figure 5.15 Tower Biology at a site in Mexico City.

conventional biological treatment plants or adversely affect the degradation
of other substances.
The LOPROX process is a method of chemical oxidation. Using cata-
lysts, organic substances in effluents are partially oxidized with pure oxygen
under pressure and at elevated temperatures. Under relatively mild reaction

conditions at temperatures below 200 C (390 F) and pressure from 5 to

20 bar (70 to 280 psi), a large number of chemical compounds that other-
wise biodegrade very slowly can be oxidized to such an extent that the resid-
ual substances generated can be more easily degraded by subsequent aerobic
biological treatment.
The new process has proved itself time and again in Bayer’s waste man-
agement system.
Eight plants are in operation pretreating an effluent stream of up to
3
60 m /h. Since 1982 Bayer has gathered considerable expertise in the use
of this process.
In the chemical industry, effluent is disposed of in an integrated wastewa-
ter management system. The central biological treatment plant is comple-
mented and supported by a series of decentralized measures, including
LOPROX. Bayer Tower Biology has been used successfully for more than
10 years for the biological treatment of industrial effluents. This technology
represents a new generation of biological waste water treatment plants.
Bio-oxidation is carried out in closed tanks holding a water column between
10 and 25 m high rather than in conventional open basins. To date, 14 Tower
3
Biology units have processed between 299 and 90,000 m /day of effluent.