Abstract: In an apparatus and process described, an organic fraction of solid waste is separated from light contaminants such as plastics and heavy contaminants such as grit. The organic fraction is subsequently processed by anaerobic digestion, which converts volatile solids to gas. In a first stage of the process, the waste is processed through a separator such as a vertical mill, which removes light fraction contamination, reduces organics particle size and dilutes the waste to thereby produce a slurry. In a second stage of the process, the slurry passes through a grit removal system, which removes heavy and settleable material, for example by way of a hydrocyclone. The light and heavy fraction contaminants are not carried through to the digestion process. The particle size of the organics is also reduced to facilitate digestion and the slurry has a dry solids concentration suitable for anaerobic digestion.

Abstract: In an apparatus and process described, an organic fraction of solid waste is separated from light contaminants such as plastics and heavy contaminants such as grit. The organic fraction is subsequently processed by anaerobic digestion, which converts volatile solids to gas. In a first stage of the process, the waste is processed through a separator such as a vertical mill, which removes light fraction contamination, reduces organics particle size and dilutes the waste to thereby produce a slurry. In a second stage of the process, the slurry passes through a grit removal system, which removes heavy and settleable material, for example by way of a hydrocyclone. The light and heavy fraction contaminants are not carried through to the digestion process. The particle size of the organics is also reduced to facilitate digestion and the slurry has a dry solids concentration suitable for anaerobic digestion.

Abstract: A biofilm carrier screen is adapted for use with a moving bed bioreactor (MBBR). The screen has a screening body connected to an effluent pipe. The effluent pipe optionally has two parts separated by a union, preferably a pitless adapter. The screening body can be lifted from a bioreactor tank for maintenance after disconnecting the union. The screening body may have an aerator to provide bubbles to disperse biofilm carriers from the screening body. The screening bod may extend downwards from a mount near the top of the tank. In the case of an anaerobic MBBR, the screening body may extend downwards from a service box through a cover over the tank.

Abstract: A biofilm carrier screen is adapted for use with a moving bed bioreactor (MBBR). The screen has a screening body connected to an effluent pipe. The effluent pipe optionally has two parts separated by a union, preferably a pitless adapter. The screening body can be lifted from a bioreactor tank for maintenance after disconnecting the union. The screening body may have an aerator to provide bubbles to disperse biofilm carriers from the screening body. The screening bod may extend downwards from a mount near the top of the tank. In the case of an anaerobic MBBR, the screening body may extend downwards from a service box through a cover over the tank.

Abstract: A device for providing an RF signal burst to an external load includes a voltage-controlled oscillator to generate a drive signal having a frequency f.sub.VCO fixed by an oscillator control signal. An RF driver stage coupled to the external load receives the drive signal and generates an RF signal burst in response to the drive signal. A current transformer coupled between the RF driver stage and the external load senses the current in the RF driver stage and generates a reference current having the same phase as the sensed current. A phase detector receives the reference current along with the drive signal and generates a phase detection signal that provides a measure of the phase of the current in the RF driver stage with respect to the drive signal. The phase detection signal can be used to adjust the oscillator control signal to drive the oscillator frequency to a desired value.