A system and method using a subterranean biological reactor can include a pre-reactor storage unit configured to receive a feedstock including a slurry of biologically derived material and at least one pump configured to pump the effluent from the pre-reactor storage unit. The system may include at least one wellbore containing a subterranean biological reactor configured to receive the effluent from the pre-reactor storage unit. At least a portion of the subterranean biological reactor may be configured to perform anaerobic digestion upon the effluent to generate a biogas.

A method for treating wastewater comprising subjecting a sulfate containing wastewater to Fe(III) iron dosing in an anaerobic bioreactor containing one or more of an iron reducing bacteria and one or more of a sulfate reducing bacteria, and one or more of a fermentative bacteria, and adjusting a dosage of the Fe(III) iron in the anaerobic bioreactor to achieve a Fe/Sulfate molar ratio that is equal to or greater than 0.50, and removing an effluent from the anaerobic bioreactor that is a treated wastewater. A wastewater treatment system is provided having a wastewater reservoir, a ferric iron solution reservoir, an anaerobic bioreactor, and an effluent reservoir.

A method for treating wastewater comprising subjecting a sulfate containing wastewater to Fe(III) iron dosing in an anaerobic bioreactor containing one or more of an iron reducing bacteria and one or more of a sulfate reducing bacteria, and one or more of a fermentative bacteria, and adjusting a dosage of the Fe(III) iron in the anaerobic bioreactor to achieve a Fe/Sulfate molar ratio that is equal to or greater than 0.50, and removing an effluent from the anaerobic bioreactor that is a treated wastewater. A wastewater treatment system is provided having a wastewater reservoir, a ferric iron solution reservoir, an anaerobic bioreactor, and an effluent reservoir.

A system of controllable separation between recyclable organic waste and graywater sewage is described; a respective method for controllable separating recyclable organic waste from graywater sewage is further described; the system includes: a garbage disposal unit, and a separation module; the method includes: draining both the graywater sewage and the recyclable organic waste; processing the organic waste into a semiliquid mixture or slurry of round organic matter and fluid; discharging the semiliquid mixture or slurry of ground organic matter and fluid and the graywater sewage; and releasing the semiliquid mixture or slurry of ground organic matter and fluid; releasing the graywater sewage; and separating the semiliquid mixture or slurry of ground organic matter and fluid from the graywater sewage.

A system of controllable separation between recyclable organic waste and graywater sewage is described; a respective method for controllable separating recyclable organic waste from graywater sewage is further described; the system includes: a garbage disposal unit, and a separation module; the method includes: draining both the graywater sewage and the recyclable organic waste; processing the organic waste into a semiliquid mixture or slurry of round organic matter and fluid; discharging the semiliquid mixture or slurry of ground organic matter and fluid and the graywater sewage; and releasing the semiliquid mixture or slurry of ground organic matter and fluid; releasing the graywater sewage; and separating the semiliquid mixture or slurry of ground organic matter and fluid from the graywater sewage.

A method for treating an aqueous fluid comprising a biodegradable organic substance in an installation comprising an upflow bioreactor containing a sludge bed, said sludge bed comprising biomass, an external separator, and a conditioning tank, the method comprising: treating the fluid in the conditioning tank; feeding the treated fluid into a lower part of the bioreactor and forming biogas; withdrawing the fluid from an upper part of the bioreactor, which withdrawn fluid comprises biomass; feeding the aqueous fluid withdrawn from the upper part of the bioreactor into the external separator wherein the aqueous fluid comprising the biomass is separated into a liquid phase, and a fluid phase enriched in biomass; returning said fluid phase enriched in biomass from the external separator to the bioreactor; and returning a part of said liquid phase to the conditioning tank.

Methods for generating methane from animal waste by anaerobic digestion using bacteria. A screen separator removes suspended solids greater in size than a predetermined size ranging from about 50μ to about 150μ. An electrocoagulation unit electrochemically hydrolyses the waste, causing particles to settle out. A dissolved carbon air flotation has a CO.sub.2 bubbler for separating large particles from small particles by flotation. An anaerobic digester produces biogas. The digester has a biocurtain for growing the bacteria and a heat exchanger for heating the bacteria. The biocurtain surface is convoluted to retain the bacteria. A membrane module removes CO.sub.2. A knock out pot for removes droplets of water. A scrubber removes water vapor, particulates, and contaminant gas. A compressor boosts pressure. A gas chromatograph monitors the biogas composition. A flare skid lowers excess pressure for safety. Biogas is injected into a local pipeline system. A process control is used for controlling the anaerobic waste digestion system.

Systems and methods for wastewater treatment are described. In some embodiments, a wastewater treatment system may include a container configured to receive and store at least a portion of incoming wastewater during a digestion process that generates biogas and a biogas burner. The biogas burner may be arranged to receive and burn at least a portion of the biogas generated by the digestion process. The system may be configured to heat solids separated from the wastewater such that: (i) the solids separated from the wastewater are maintained at a temperature of at least 70° C. for at least 30 minutes; and/or (ii) a water content of the solids separated from the wastewater is less than 15% by mass.

Systems and methods for wastewater treatment are described. In some embodiments, a wastewater treatment system may include a container configured to receive and store at least a portion of incoming wastewater during a digestion process that generates biogas and a biogas burner. The biogas burner may be arranged to receive and burn at least a portion of the biogas generated by the digestion process. The system may be configured to heat solids separated from the wastewater such that: (i) the solids separated from the wastewater are maintained at a temperature of at least 70° C. for at least 30 minutes; and/or (ii) a water content of the solids separated from the wastewater is less than 15% by mass.

Disclosed are methods of dewatering solid byproduct. In some embodiments, the solid byproduct contains particles and is produced from a fermentation process for making an oxygenated compound such as ethanol. The method comprises a chemical sequence for conditioning (pre-treating) the solid byproduct to be dewatered. The solid byproduct (in water) is treated with alkaline material to increase its pH to about 7-8.5. Coagulant is added to the alkaline-treated solid byproduct to reduce charge on the solid byproduct. An agglomerating polymer is then added to increase the average size of the solid byproduct particles to a desired size (e.g., at least about 1 mm). Dewatering can further use known technologies such as screw press, belt press, filter press, centrifuge, and/or a dryer to separate the conditioned or pre-treated byproduct from water. Also disclosed are methods of producing oxygenated product, as well as methods of producing animal feed and/or fertilizer, respectively.