Disclosed are apparatus and methods for treating wastewater. In one example a system for treating wastewater treatment is provided. The system comprises a biological reactor having an inlet in fluid communication with a source of wastewater and an outlet, the biological reactor configured to treat wastewater from the source of wastewater and output a biologically treated wastewater from the outlet, a solids-liquid separation system having an inlet in fluid communication with the outlet of the biological reactor and configured to separate the biologically treated wastewater into a solids-lean effluent and a solids-rich waste activated sludge (WAS), a treatment subsystem comprising a digester, an inlet in fluid communication with a WAS outlet of the solids-liquid separation system, and an outlet for providing ballasted and digested WAS, and a ballast feed system configured to deliver ballast to one of the biological reactor and the treatment subsystem.

A method of treating produced water, such as frac flowback, that includes pre-treating the produced water which is followed by a crystallization process that produces a condensate that typically includes ammonia and benzene. The ammonia and benzene concentration is reduced by biologically nitrifying and denitrifying the condensate. This produces an effluent that is directed to a solids-liquid separation process that removes suspended solids. The solids-liquid separation process produces another effluent that is subjected to a benzene polishing process that further reduces the benzene concentration of the effluent produced by the solids-liquid separation process.

The present invention concerns a process for treating waters containing at least two different dissolved inorganic salts which do not precipitate and/or crystallize in the same conditions by precipitation and ballasted flocculation, in which the ballast is produced in situ.

A high-solids wastewater treatment system is disclosed. The wastewater treatment system includes a ballasted reactor, a solids-liquid separation subsystem, a pre-treatment subsystem, a ballast feed subsystem, and a ballast recovery subsystem. The high-solids wastewater treatment system can include a reaction tank, a thickener, and a filter press. A method of treating high-solids wastewater is also disclosed. The method includes contacting a wastewater feed with a coagulant or flocculant, thickening the dosed wastewater, treating the effluent with a ballast, settling the treated wastewater, and conveying the ballasted sludge to the wastewater feed, dosed wastewater, or treated wastewater. The wastewater feed may have more than 500 mg/L of total suspended solids. The wastewater feed may contain inorganic solids.

The present invention generally relates to a novel process in which thin stillage is processed to produce algae oil and protein rich biomass as well as other energy rich byproducts. In accordance with a preferred embodiment, thin stillage is removed from an evaporator during the evaporation process to produce mid-stillage. This mid-stillage is preferably routed to a new process where it is directed to a pre-treatment centrifuge to remove suspended solids, sludge and corn oil. Thereafter, the mid-stillage is preferably cooled and then directed to a fermentation tank where the mid-stillage is subject to a batch fermentation process with algae seed fed from an algae inoculation system. Once the batch is harvested, the oil-rich algae/mid-stillage is then preferably heated to rupture the cells and liberate the oil. Thereafter, the oil-rich algae/mid-stillage is preferably processed by a centrifuge which produces solids, a light phase oil and a clean mid-stillage stream that can be evaporated to a very high level of solids.

A system and method of treating wastewater. In one embodiment, the system comprises a biological reactor fluidly connected to a source of wastewater and having a treated wastewater outlet, a fixed film biological reactor connected to the source of wastewater and having a fixed film effluent outlet, and a ballasted system fluidly connected to the fixed film effluent outlet. The ballasted system may comprise a ballast reactor tank configured to provide a ballasted effluent, and a source of ballast material fluidly connected to an inlet of the ballast reactor tank. The system may further comprise a bypass line having an inlet fluidly connected to the source of wastewater, a first outlet fluidly connected to the ballasted system, and a second outlet fluidly connected to the fixed film biological reactor, the bypass line configured to bypass the fixed film biological reactor.

The invention relates to a water treatment plant which comprises means (38) for supplying the water to be treated, means (31) for supplying coagulant reagent (21), a flocculation-decantation device (1) which has means (32) for dispensing the flocculant reagent, means (33) for distributing ballast, means (39d) for extracting decantation sludge and means (9) for discharging water that has been treated, a line (8) for supplying coagulated water to the flocculation-decantation device (1), means (24) for separating the ballast contained in the ballasted sludge followed by means (36) for recycling the ballast back into said flocculation-decantation device (1), characterised in that said device (1) comprises an outer tank (2) that has a first hopper (4), and at least one inner tank (3) that has a second hopper (5) and is arranged inside said outer tank (2); the inner tank (3) receiving the flocculant and the ballast and comprising stirring means (10), wherein a peripheral space is disposed between the inner tank (3) and the outer tank (2); the second hopper (5) having an opening (6) which opens into the first hopper (4); and said first hopper (4) having an outlet that communicates with the means (34) for discharging ballasted sludge, wherein the means (9) for discharging water that has been treated are disposed in the upper portion of said outer tank (2). The invention also relates to a method for implementing a plant of this types.

The invention relates to a water treatment plant comprising: means (1) for supplying water for treatment, wherein said water has been coagulated previously, a flocculation-decantation device (11) having means (5) for dispensing at least one flocculant reagent, means (6) for dispensing at least one ballast, means (20d) for extracting decantation sludge, means (9) for discharging the treated water, means (14) for separating said ballast contained in the ballasted sludge, and means (8) for recycling the ballast that has been cleaned in this manner back into the flocculation-decantation device (11), characterised in that: said flocculation-decantation device (11) has a single tank (12) in the lower portion of which a stirring mechanism (13) is arranged; wherein said single tank (2) comprises slats (10) in its upper portion; and said slats are separated from the stirring mechanism (13) by a distance d which is between approximately 0.5 metres and approximately 3 metres. The invention also relates to a method using said plant.

The present invention generally relates to a novel process in which thin stillage is processed to produce algae oil and protein rich biomass as well as other energy rich byproducts. In accordance with a preferred embodiment, thin stillage is removed from an evaporator during the evaporation process to produce mid-stillage. This mid-stillage is preferably routed to a new process where it is directed to a pre-treatment centrifuge to remove suspended solids, sludge and corn oil. Thereafter, the mid-stillage is preferably cooled and then directed to a fermentation tank where the mid-stillage is subject to a batch fermentation process with algae seed fed from an algae inoculation system. Once the batch is harvested, the oil-rich algae/mid-stillage is then preferably heated to rupture the cells and liberate the oil. Thereafter, the oil-rich algae/mid-stillage is preferably processed by a centrifuge which produces solids, a light phase oil and a clean mid-stillage stream that can be evaporated to a very high level of solids.

Disclosed herein are systems for removing particulate matter from a fluid, comprising a particle functionalized by attachment of at least one activating group or amine functional group, wherein the modified particle complexes with the particulate matter within the fluid to form a removable complex therein. The particulate matter has preferably been contacted, complexed or reacted with a tethering agent. The system is particularly advantageous to removing particulate matter from a tailing solution.