Abstract: A process is provided for the removal of heavy metals from wastewater prior to being fed to a wastewater treatment installation, with anaerobic sludge to cause the anaerobic sludge to absorb heavy metals in the wastewater. Thus, the heavy metals depleted wastewaters can then be treated in a conventional treatment plant and thereafter, the resultant sludge can be directly employed for agricultural purposes without requiring further treatment to remove heavy metals therein. To effect the process a preferred reactor is made up of two parts, a cylindrical mixing tank and a superposed funnel-shaped sedimentation zone.

Abstract: A process and apparatus are provided for the biological purification of phosphate-containing wastewater, wherein the wastewater is treated, in the presence of activated sludge at least a portion of which is fixed on a carrier material. The process is conducted in at least one aerobic, an anaerobic, and optionally an anoxic zone, to thereby discharge a substantially phosphate-free wastewater stream. In order to attain a high purifying effect with low cost expenditure, the activated sludge is carried on a movable carrier. The carrier material is conveyed from the anaerobic zone, optionally through the anoxic zone, to the aerobic zone, and simultaneously a like amount of carrier material is returned from the aerobic zone, optionally through the anoxic zone, to the anaerobic zone. In this process, the activated sludge is enriched with phosphates, and a portion of the phosphate-enriched activated sludge is separated from the discharged effluent.

Abstract: For the biological purification of wastewater in a reactor in the presence of open-pore and compressible carrier material for biomass, the carrier material, prior to its use in the reactor, is loaded with bacteria, finely divided, inorganic and/or organic compounds, selected for wastewater purification, and is then either stored or used in the process, the loaded carrier being especially useful for decreasing the start-up time of a wastewater treatment plant.

Abstract: For the biological purification of wastewater in a reactor in the presence of open-pore and compressible carrier material for biomass, the carrier material, prior to its use in the reactor, is loaded with bacteria, finely divided, inorganic and/or organic compounds, selected for wastewater purification, and is then either stored or used in the process, the loaded carrier being especially useful for decreasing the start-up time of a wastewater treatment plant.