A system and a method for producing biomass from a mixed community of algal species. The method comprises the steps of culturing the mixed community of at least two algal species as biofilms on transparent surfaces having structural features and an optical filter, providing a continuous supply of a culture medium comprising at least 0.5 mol/L aqueous (bi)carbonate and having a pH greater than 9. The method disclosed herein facilitates online monitoring of mixed community productivity by the quantification of oxygen production.

A bioreactor is provided that includes a main reactor having a configuration selected from the group consisting of stirred and unstirred tank reactor, trickle bed reactor (TBR), cocurrent contactor (CCC), moving bed bioreactor (MBBR), and a bubble column reactor. The bioreactor also includes a growth reactor continuous with the main reactor and having a configuration selected from the group consisting of stirred and unstirred tank reactor, trickle bed reactor (TBR), cocurrent contactor (CCC), moving bed bioreactor (MBBR), and a bubble column reactor. A method is also provided where acetogenic bacteria are contacted with syngas in a growth fermentor section of a reactor vessel that is continuous with a main fermentor section of a reactor vessel.

A methane fermentation system which can efficiently generate methane gas is provided. The methane fermentation system decomposes an organic waste with an anaerobic microorganism to cause methane fermentation so as to generate the methane gas. The methane fermentation system includes a wet bead mill which finely pulverizes the organic waste. The methane fermentation system also includes a methane fermentation chamber in which the organic waste finely pulverized in the wet bead mill is decomposed with the anaerobic microorganism to cause the methane fermentation so as to generate the methane gas.

A method for producing a fuel includes transporting one or more pressure vessels containing pressurized biogas from a first location to a second location, and removing biogas from the one or more pressure vessels at the second location. The fuel production process is improved by controlling the decanting flow rate to provide a total decant time greater than 30-40 minutes, by actively heating biogas contained within the one or more pressure vessels, or some combination thereof.

A multi-stage anaerobic digester is designed to treat a high solids, stackable feedstock. The system may also receive a pumpable feedstock such as a slurry or sludge. In a first stage, the digestate circulates in one direction around a raceway such that the digestate may pass a feed inlet multiple times before leaving the first tank. An optional side stream loop withdraws fibrous material from near the top of the reaceway and return digestate with chopped fibers, preferably lower and further along the raceway. An outlet from the raceway located near, but upstream of the feed inlet discharges partially digested substrate to a second stage, which is operated as a stirred tank reactor. The two stages may be provided in a single tank with an internal wall separating a ring shaped outer portion from a cylindrical inner portion. The digester may be operated in a thermophilic temperature range.

Disclosed is a bioreactor, especially a plug flow bioreactor, including an agitator running along a longitudinal axis for thoroughly mixing a dry solid biomass that is to be outgassed in a fermentation chamber. In said bioreactor, an agitator shaft is mounted exclusively in two opposite end walls of the fermentation chamber while at least one free end of the agitator is connected to a drive unit outside the fermentation chamber.

A process and system for producing a synthetic hydrocarbon having a desired H/C ratio is disclosed. Organic material is biochemically digested in a two stage biodigester for separately producing a hydrogen containing biogas substantially free of methane in a first stage and a methane containing biogas in a second stage. The methane containing biogas is reformed in a first reformer to generate hydrogen gas and carbon monoxide gas, which are then combined in a mixer with the hydrogen containing biogas into a syngas in amounts to achieve in the syngas an overall H/C ratio substantially equal to the desired H/C ratio. The syngas is reacted with a catalyst in a second reformer, a Fischer-Tropsch (FT) reactor, to produce the hydrocarbon. Using a two stage biodigester allows for the generation of separate hydrogen and methane streams, a more economical generation of the FT syngas and reduced fouling of the FT catalyst.

A facility for the recycling of biomaterial with a fermentation stage, whereby the fermentation stage has a fermentation chamber for the production of biogas through anaerobic fermentation of the biomaterial, and with a hygiene stage that is positioned downstream from the fermentation stage, whereby the hygiene stage has a hygienization chamber for the reception and the thermal hygienization of biomaterial discharged from the fermentation stage. A process for the recycling of biomaterial by zymosis is also provided, whereby biogas is produced in a fermentation stage through anaerobic fermentation of the biomaterial, whereby the biomaterial is, after flowing through the fermentation stage, conveyed to a hygiene stage in which the biomaterial thermal is hygienized, and whereby the biomaterial is, after flowing through the hygiene stage, made available as recyclable agricultural, hygienized fermentation residue.

A mixing device for an application in a container including a rotatable shaft; a drive device through which the rotatable shaft is drivable; and at least one mixing element arranged at the shaft, wherein the mixing element is rotatable together with the shaft, wherein the shaft includes a support device connected with the shaft, wherein the support device is arranged in an end portion of the shaft that is oriented away from the drive device, wherein the shaft is rotatable about its longitudinal axis relative to the support device, wherein the mixing device is supportable through the support device in a receiving device connected with the container, wherein the support device is moveable by a straight bearing or a rolling element bearing along a guide device into the receiving device, wherein the straight bearing includes at least one sliding surface that is moveable on a corresponding sliding surface.

A process for reducing the production of sludge by municipal or industrial wastewater purification plants, comprising a step of mesophilic or thermophilic anaerobic digestion (20), or anaerobic digestion combining these two operating modes, of a stream of sludge to be treated (1), and at least one biological solubilization anaerobic treatment step (30); the process comprises, upstream of the anaerobic digestion step, a step of dehydration (10) of the sludge to be treated, followed by a step of mixing (15) the dehydrated sludge with a recirculated fraction of sludge that is more liquid, originating from recycling of the digestion (20), and/or from the anaerobic treatment step (30), and/or centrates originating from a final dehydration (50) of the treated sludge, wherein the recirculation rate is chosen such that the mixture has a dryness suitable for digestion, this mixture then being directed towards the digestion.