An apparatus for facilitating particle separation by density includes a separator having an inner surface surrounding a rotation axis and defining a particle path from an input end to an axially spaced output end. The inner surface includes a plurality of axially spaced dividers having respective inner positions, defining at least in part respective axially spaced retainers for collecting particles during rotation of the separator. The retainers each include at least one fluid inlet for fluidizing particles in the retainer during operation. The dividers include a first pair of adjacent dividers and a second pair of adjacent dividers, the first pair nearer the input end than the second pair, wherein a first divider slope of the first pair is greater than a second divider slope of the second pair and wherein each of the first and second divider slopes is zero or positive. Other systems, apparatuses and methods are disclosed.

A drilling mud treatment unit (100) comprises a primary duct (10) for feeding coagulated drilling mud, an in-line flocculation system (20) for flocculating the coagulated drilling mud flowing in the primary duct (10), and at least one hydrocyclone (30) fed by the primary duct (10) and arranged downstream from the flocculation system (20). The hydrocyclone (30) has an overflow orifice (32) for receiving a liquid product resulting from treatment of the drilling mud and an underflow orifice (34) for receiving a solid product resulting from treatment of the drilling mud. The overflow orifice (32) presents an overflow diameter (Do) and the underflow orifice presents an underflow diameter (Du), and the underflow diameter (Du) is greater than 1.1 times the overflow diameter (Do).

A drilling mud treatment unit (100) comprises a primary duct (10) for feeding coagulated drilling mud, an in-line flocculation system (20) for flocculating the coagulated drilling mud flowing in the primary duct (10), and at least one hydrocyclone (30) fed by the primary duct (10) and arranged downstream from the flocculation system (20). The hydrocyclone (30) has an overflow orifice (32) for receiving a liquid product resulting from treatment of the drilling mud and an underflow orifice (34) for receiving a solid product resulting from treatment of the drilling mud. The overflow orifice (32) presents an overflow diameter (Do) and the underflow orifice presents an underflow diameter (Du), and the underflow diameter (Du) is greater than 1.1 times the overflow diameter (Do).

A method of treating and grading contaminated particulate material includes i. physically breaking up the particulate material to separate the particles thereof; ii. rinsing and grading the particulate material to separate the particulate material into an oversize fraction and an undersize fraction; iii. washing and grading the oversize fraction to produce one or more treated aggregate products; iv. passing the undersize fraction through a high shear washing process to separate contaminants therefrom; v. fluidising and cleaning the undersize fraction in a classification tank to produce one or more treated sand products at an underflow thereof by passing clean water upwardly into the classification tank. Optionally, waste water resulting from stages (ii), (iii) and (iv) is treated to form process water, a portion of which is used in stage (ii), a portion of the process water undergoing one or more further treatment processes to produce clean water used in stage (v).

Methods and systems for treating oil sands tailings streams using multiple dosages of lime are disclosed herein. In some embodiments, the method comprises providing a tailings stream including 3-40% solids by total weight, combining the tailings stream with a first dosage of lime to produce a first mixture having a pH of less than 12.0, and then combining the first mixture with a polymer to produce a second mixture. In some embodiments, the method can further include combining the second mixture with a second dosage of lime to produce a third mixture having a pH greater than 12.0, and dewatering the third mixture in a centrifuge unit and/or a pressure filtration unit to produce a product stream having 55% or more solids by weight.

In a process for treating wastewater from a combined gasification and Fischer-Tropsch (F-T) process, feedstock derived from Municipal Solid Waste or the like is gasified in a reactor (R) and treated in a cleanup unit (C) which generates a first wastewater stream (1st WWT STREAM) containing salts and inorganic pollutants. The first wastewater stream is treated in a treatment unit (T1) to remove inorganic pollutants derived from the syngas The treatment comprises a) degassing, and subsequently b) neutralising the first wastewater stream before treatment in a Dissolved Air Flotation unit (72c) and filtering in a moving sand bed or similar (72d) to remove solids, and a stripping process to remove ammonia. A second wastewater stream (2.sup.nd WWT Stream) containing organic pollutants but being low in salts arises from the F-T process and is treated separately to allow recycling within the F-T process.

The invention generally relates to osmotically driven membrane systems and processes and more particularly to increased brine concentration for zero liquid discharge using osmotically driven membrane systems and processes and the related draw solute recovery techniques for the osmotically driven membrane systems and processes.

The current process relates to the treatment of a primary sludge that is produced from waste water treatment facilities such as a pulp mill or a pulp and paper mills. It further relates to a process of using the primary sludge in the production of cellulosic ethanol. It further relates to the use of the treated primary sludge in the manufacture of recycled linerboard.

An extraction manifold for extracting digestate from a covered lagoon digester includes a digester vessel being shaped generally as a rectangular prism lacking an upward facing face and having a floor sloping generally downward from an intake face to an extraction face of the digester vessel. The intake face and extraction face are oriented vertically, situated in opposed relation on a longer horizontal axis. Each effluent pipe terminates in an extraction nozzle on one end and an independently addressable actuatable valve on the opposite end. Each actuatable valve communicates with a manifold plenum such that actuation of the valve draws digestate from the floor in a region of the floor adjacent to the extraction face and in proximity to the extraction nozzle. A valve controller actuates valves to remove digestate from the region of the floor adjacent to the extraction face. The valve controller includes sensors to monitor biogas production.

An apparatus for filtration has a feed of sludge, containing liquid, solids and gases fed into a tank, the tank containing at least one spinning separation filter comprising a filter cone set having a filter screen, and a barrier cone, arranged roughly in parallel, and defining a conical workspace between them, the conical workspace having a peripheral opening to the tank and a central opening communicating with the interiors of one or more hollow shafts supporting the barrier cone and the filter cone, the upper shaft supporting the barrier cone having an upper axial channel for the exit of gases, the lower shaft supporting the center of the filter cone having a lower axial channel for the exit of liquid or oil, motor means for producing rotation in said at least one spinning separation filter, and a filtrate liquid reservoir located underneath the filter cone for capturing the filtrate passing through the filter screen.