Abstract: An operating method for a batch process, the batch process comprising a plurality of operating phases and within each phase there is provided at least one operating mode, one of the modes of each phase being a standby mode or its equivalent, wherein a transition from a first phase to a second phase requires that the first phase be initialised to its standby mode or equivalent and upon completion of the phase change the second phase enters its standby mode or equivalent.

Abstract: An apparatus (10) for the pressurized recirculation of organic material comprising a reactor vessel (12) capable of being pressurized and in which both anaerobic digestion and aerobic composting of organic material may occur, the reactor vessel (12) having both an inlet (14) and an outlet (16) for organic material, together with a conveyor means (18, 20, 22, 28, 29, 30, 32, 34 and 36) to convey organic material to the inlet (14) and from the outlet (16), whereby organic material may be transferred between the outlet (16) and the inlet (14) to achieve recirculation and rearrangement thereof while maintaining a pressurized state. A method for the pressurized recirculation of organic material is also described.

Abstract: A dewatering method comprising the method steps of: (i) Conveying a material to be dewatered part way along the length of a housing (14) by way of a screw (12) that is driven by a motor (22); (ii) Monitoring the rate of change of power demand on the motor (22); (iii) Adjusting the level of backpressure to which the material to be dewatered is exposed based on the rate of change of power demand on the motor (22) as obtained under step (ii); and (iv) Forming a residual plug of dewatered material at an open end (20) of the housing (14). A dewatering apparatus (10) is also described.

Abstract: An apparatus (10) for the pressurised recirculation of organic material comprising a reactor vessel (12) capable of being pressurised and in which both anaerobic digestion and aerobic composting of organic material may occur, the reactor vessel (12) having both an inlet (14) and an outlet (16) for organic material, together with a conveyor means (18, 20, 22, 28, 29, 30, 32, 34 and 36) to convey organic material to the inlet (14) and from the outlet (16), whereby organic material may be transferred between the outlet (16) and the inlet (14) to achieve recirculation and rearrangement thereof whilst maintaining a pressurised state. A method for the pressurised recirculation of organic material is also described.

Abstract: A process control method, the method comprising the steps of: (i) Passing a portion of a biomass containing liquid from a first reactor (12) in which a batch anaerobic digestion of organic material is being or has been conducted to a liquid storage vessel (14), methane being produced in both the first reactor (12) and the liquid storage vessel (14); (ii) Passing a portion of the liquid from the liquid storage vessel (14) back to a first reactor (12) that may or may not be the same reactor (12) of step (i); (iii) Passing a portion of the liquid from either or both of the first reactor (12) and the liquid storage vessel (14) to a second reactor (16); and (iv) Passing a portion of the liquid from the second reactor (16) to either the liquid storage vessel (14) or to the first reactor (12), wherein the direction of liquid to the second reactor (16) allows control of the level of volatile fatty acids (VFA) in the liquid to be returned to the first reactor (12) by way of exposure to additional anaerobic methanogeni