A digital twin model based operation and optimization of a reverse osmosis plant uses a data processing system to receive data for a reverse osmosis membrane in a plant that with a plurality of assets. The data processing system can determine a level of performance of the membrane based on the data for the membrane input into a model generated with sa topology indicative of one or more relationships and a flow path between the plurality of assets, predict, based on the model and responsive to the level of performance input into an optimization function for the plant, a time at which the level of performance degrades below a threshold, and provide an indication of the time at which the level of performance degrades below the threshold predicted using the optimization function to cause servicing of the membrane used to process the fluid at the plant.

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.

A method of removing organic carbon in biological wastewater treatment includes the steps of: (a) oxidizing organic carbon to carbon dioxide with elemental sulfur as an electron carrier, and reducing the elemental sulfur to sulfide; (b) oxidizing the sulfide to elemental sulfur by recycled nitrate through controlling one or more of a recycling ratio to maintain an oxidation reduction potential (ORP) within the range of −360 my to −420 mv, using an auto ORP controller; (c) recycling the elemental sulfur formed during oxidation of the sulfide back to the oxidation of the organic carbon; and (d) oxidizing ammonium to nitrate then partially recycled back for sulfide oxidation.

Low strength wastewater such as municipal sewage is treated using an anaerobic digester. In some examples, a wastewater stream is separated into a solids rich portion and a solids lean portion. The solids lean portion is treated, for example to remove nitrogen. The solids rich portion is treated in an anaerobic digester, preferably with influent or recuperative thickening. In another example, the wastewater stream is fed to an anaerobic digester and solid-liquid separation stages downstream of the digester return active bacteria and undigested organics to the digester. Both cases may use a process train comprising treatment in an anoxic tank followed by a nitritation tank with a portion of the effluent from the nitritation tank recirculated to the anoxic tank to provide nitritation and denitritation.

The present invention is a composting bioreactor system that continually receives biodegradable solid wastes, waste waters and exhaust gases, automatically recycles the biodegradable wastes into nutrients and heat energy, and automatically supplies the nutrients and heat into an integrated hydroponic or aquaponic system. This invention together with integrated food growing system may be installed onsite such as balconies, backyards and premises of restaurants and food factories etc. therefore may lead to zero mileage targets both for recycling wastes and for supplying foods. This invention integrates composting process and aquaponic technology together and may establish a closed-loop recirculation of both water and gases therefore upgrades aquaponics into compoponics. A compoponic system has both soil and soilless growing beds and mimics nature recirculating nutrients, carbon and energy among human being, animals, microorganisms and plants by way of photosynthesis, slow burning by cellular respiration and burning by combustion.

Disclosed are methods of treating wastewater using a membrane bioreactor and achieving a target phosphorus concentration for the membrane permeate stream. These methods include the steps of dosing a wastewater stream with a rare earth clarifying agent and passing the dosed wastewater stream through the membrane to obtain a membrane permeate stream with a permeate concentration that is less than the phosphorus concentration of the influent stream. This permeate concentration also can be equal to or less than a target phosphorus concentration. In the methods as disclosed herein, the rare earth clarifying agent can be chloride salts of one or more rare earth elements and in certain embodiments, the rare earth clarifying agent can be CeCl.sub.3 and LaCl.sub.3.

A method for treating wastewater includes passing wastewater through a pretreatment component to remove at least portions of one or more contaminants from the wastewater and generate a permeate and passing the permeate through an electro-chemical cell component to remove at least remaining portions of the one or more contaminants and generate an exudate.

Disclosed is a split type continuous operation micro-grid dynamic membrane bioreactor. The split type continuous operation micro-grid dynamic membrane bioreactor comprises a biological treatment unit and a drum type dynamic membrane filtration unit, wherein the biological treatment unit comprises a microbiological treatment tank, and a water inlet pipe is arranged on the microbiological treatment tank; the drum type dynamic membrane filtration unit comprises a filter tank, and a drum micro-grid dynamic membrane mechanism is arranged in the filter tank; the drum micro-grid dynamic membrane mechanism comprises a filter drum, a backwashing device is arranged above the filter drum, and a sludge collecting bank is arranged in the filter drum; a water outlet is formed in the bottom of the filter tank; a mixed liquid pipe is arranged between the microbiological treatment tank and the filter drum; and a sludge discharge header pipe is arranged on the sludge collecting tank.

Treating distilled water with bacteria and other micro-organisms to remove nitrogen compounds from the distilled water. The distilled water may be produced from pretreating and distilling wastewater, such as wastewater from oil and natural gas production. The treatment steps of the distilled water include subjecting the water to microbial action under both anoxic and aerobic conditions and employing a membrane bioreactor to further purify the water. The purified water is still further purified by either reverse osmosis or ion exchange systems.

Some embodiments comprise membranes comprising a first layer comprising a porous graphene-based material; a second layer comprising a porous graphene-based material; a channel positioned between the first layer and the second layer, wherein the channel has a tunable channel diameter; and at least one spacer substance positioned in the channel, wherein the spacer substance is responsive to the environmental stimulus. In some cases, the membranes have more than two layers of porous graphene-based material. Permeability of a membrane can be altered by exposing the membrane to an environmental stimulus. Membranes can be used in methods of water filtration, immune-isolation, timed drug release (e.g., sustained or delayed release), hemodialysis, or hemofiltration.