An apparatus for refractory organics conversion into biogas includes an anaerobic digester configured to be fed with organic material comprising refractory organics and to generate biogas and a digestate comprising at least a part of the refractory organics, wherein the apparatus comprises a device for a controlled partial oxidation of the refractory organics comprising an inlet configured to be fed with refractory organics and means configured to control the residence time of the refractory organics within the device for a controlled partial oxidation, so as to partially degrade refractory organics. A method for refractory organics conversion into biogas carried out using such an apparatus is also provided.

The present invention relates to a method for cleaning process water circulated in a paper recycling system, comprising a process water treatment step, which comprises at least one pre-acidification step and at least one anaerobic cleaning step, wherein at least some of the process water to be cleaned is subjected to hydrolysis and acidification in the at least one pre-acidification step and the process water thus treated is then brought into contact with anaerobic microorganisms in the at least one anaerobic cleaning step in order to break down impurities in the process water, wherein at least one saccharide-splitting enzyme is added to the process water before or during the pre-acidification step, and the pH of the process water is set to 8.0 or lower at least during the at least one pre-acidification step and during the at least one anaerobic cleaning step.

According to an example aspect of the present invention, there is provided a method of removing dissolved contaminants from an aqueous liquid. The aqueous liquid is contacted with an adsorbent which comprises a finely divided lignocellulosic material, which has been subjected to extraction to remove hemicellulose and/or other components therefrom, to bind at least a portion of the organic compounds to the adsorbent. Furthermore, the invention relates to a method for removing or separating dissolved contaminants from a liquid and to a method for producing a liquid containing hemicellulose and/or an adsorbent containing lignin and/or other components. In particular the invention concerns the use of an adsorbent lignocellulosic material for removing dissolved contaminants from a liquid.

A system and method for evaporative treatment or wastewater which minimizes scaling and system maintenance is disclosed. The apparatus can include an evaporation vessel with a heating source to evaporate water from a solution under treatment and a drain valve for draining the solution after treatment. The apparatus can also include one or more sensors configured to measure parameters of a solution under treatment and a user programmable controller to control the treatment process based on such measurements. A user can configure the controller to define the detection of a solution's critical state where contaminant concentrations are maximized yet scaling is minimized. When a critical state of the solution is reached a portion of the treated solution can be removed and the vessel refill with new wastewater thereby lowering the concentration of the remaining solution the repealing the evaporation and drain cycle until all wastewater has been treated.

A built-in micro-interface papermaking wastewater treatment system and a treatment method are provided in the present invention. The treatment system includes a papermaking wastewater tank, a grid cleaner, an adjustment tank, a centrifugal filter and a sedimentation tank which are connected in sequence, and further includes a heat exchanger, a preheater, a wet oxidation reactor, a gas-liquid separator and a biodegradation tank. A micro-interface unit for dispersing and crushing gas into gas bubbles is disposed inside the wet oxidation reactor. The micro-interface unit includes a pneumatic micro-interface generator, a gas inlet is disposed at a side wall of the wet oxidation reactor, and the gas inlet extends to an interior of the pneumatic micro-interface generator through a pipeline. By arranging the micro-interface unit inside the wet oxidation reactor of the treatment system, the consumption of air or oxygen can be reduced, which realizes low energy consumption and high treatment efficiency.

A built-in micro-interface papermaking wastewater treatment system and a treatment method are provided in the present invention. The treatment system includes a papermaking wastewater tank, a grid cleaner, an adjustment tank, a centrifugal filter and a sedimentation tank which are connected in sequence, and further includes a heat exchanger, a preheater, a wet oxidation reactor, a gas-liquid separator and a biodegradation tank. A micro-interface unit for dispersing and crushing gas into gas bubbles is disposed inside the wet oxidation reactor. The micro-interface unit includes a pneumatic micro-interface generator, a gas inlet is disposed at a side wall of the wet oxidation reactor, and the gas inlet extends to an interior of the pneumatic micro-interface generator through a pipeline. By arranging the micro-interface unit inside the wet oxidation reactor of the treatment system, the consumption of air or oxygen can be reduced, which realizes low energy consumption and high treatment efficiency.

The invention relates to 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, 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.

Provided herein are compositions and methods useful for the treatment of wastewater comprising colloidal impurities. In certain aspects and embodiments, the compositions and methods include a natural deep eutectic solvent (NADES) coagulant including a hydrogen bond acceptor and a hydrogen bond donor, wherein the NADES is a liquid at room temperature.

Water discharged from a circulating cooling water system is treated by a water recovery system including a clarification equipment and an RO membrane, and treated water is returned to the circulating cooling water system. A dispersant is added to the circulating cooling water system for dispersing scale components. The dispersant includes a polymer having a carboxyl group and having a weight average molecular weight of 5,000 or less, and permeates through the clarification equipment. The polymer having a carboxyl group and having a weight average molecular weight of 5,000 or less permeates through the clarification equipment, and performs as a scale dispersing agent for the RO membrane, preventing precipitation of scale. Since the polymer intrinsically has an anticorrosion effect, it becomes unnecessary to add a phosphoric acid compound to the cooling water system as an anticorrosion agent, or the required amount of the compound to be added can be reduced.

A membrane-free electrochemical reactor and fuel-cell having a collection chamber between a first and second chamber, a mesoporous carbon paper cathode between the first chamber and the collection chamber, a mesoporous carbon paper anode between the second chamber and the collection chamber, the cathode is coated with an oxygen reduction reaction catalyst that imparts a two-electron partial reduction reaction to hydrogen peroxide, the anode is coated with an oxygen evolution reaction coating or a hydrogen oxidation reaction coating, oxygen/air input and output ports connected to the first chamber, KOH/water input and output ports connected to the second chamber that are in an open state under an electrolyzer mode, H.sub.2/water input and output ports connected to the second chamber that are in an open state under a fuel-cell mode, a second KOH/water input port connected to the collection chamber, and a hydrogen peroxide/KOH/water output port connected to the collection chamber.