Provided is a microbial fuel cell including a cathode and an anode, wherein the cathode includes a waterproof gas diffusion layer including a siloxane and a catalyst layer including a binder, wherein a surface of the gas diffusion layer opposite the catalyst layer contacts air, and the anode includes electrogenic bacteria. Also provided is a method for making a microbial fuel cell, including fabricating a cathode, wherein fabricating includes disposing a siloxane solution onto a surface of a substrate, wherein the siloxane solution includes a siloxane and a solvent, drying the siloxane solution to form a waterproof gas diffusion layer, and placing the gas diffusion layer on a catalyst layer including a binder, and facing an anode with the cathode whereby the gas diffusion layer faces away from the anode and contacts air.

The invention concerns an online method and system for monitoring properties of an aqueous stream of an industrial process. The method comprises providing an initial aqueous stream originating from said process, the aqueous stream containing solid matter exhibiting a first settling behavior; adding modifying agent to the initial aqueous stream at an addition rate sufficient to provide a modified aqueous stream containing solid matter exhibiting a second settling behavior different from the first settling behavior; conducting a sample of the initial aqueous stream or modified aqueous stream, any combination stream comprising the modified aqueous stream or any substream of the modified aqueous stream batchwise from a sampling point to a settling vessel having a volume; and measuring the settling behavior of the solid matter in the sample locally in the settling vessel as a function of time. The invention can be used for efficient monitoring and, optionally, controlling the degree of agglomeration of pulp and paper or board manufacturing processes.

A method for removing biologically recalcitrant soluble organic compounds from wastewater simultaneously in an activated sludge process comprising an aeration tank and a solid-liquid separation unit, in which method at least one Al and/or Fe based inorganic metal coagulant is added to the wastewater in the activated sludge process and/or prior to conveying wastewater to an activated sludge process.

The present disclosure relates to methods and systems for treating a fluid produced from a biorefinery to remove contaminants, such as metals and sulfur therefrom. Biomass is pyrolysed and activated to form activated carbon used to remove such contaminants. The fluid produced from the biorefinery may be one or more of a biofuel, a biogas, and wastewater.

Provided is a microbial fuel cell including a cathode and an anode, wherein the cathode includes a waterproof gas diffusion layer including a siloxane and a catalyst layer including a binder, wherein a surface of the gas diffusion layer opposite the catalyst layer contacts air, and the anode includes electrogenic bacteria. Also provided is a method for making a microbial fuel cell, including fabricating a cathode, wherein fabricating includes disposing a siloxane solution onto a surface of a substrate, wherein the siloxane solution includes a siloxane and a solvent, drying the siloxane solution to form a waterproof gas diffusion layer, and placing the gas diffusion layer on a catalyst layer including a binder, and facing an anode with the cathode whereby the gas diffusion layer faces away from the anode and contacts air.

Methods are provided for dewatering a water stream containing entrained particles. The water stream may be a wastewater stream from a papermaking process. Separation of the entrained particles from the water is achieved using a clarifying composition that contains a vinylamine-containing polymer or precursor(s) thereof. The vinylamine-containing polymer acts as a flocculant to effectuate separation. Then, the mixture is separated in a clarifier unit to produce a clarified water stream and clarifier bottoms.

Described herein is a process for upgrading effluent treatment plants for pulp and paper production processes, where salts are removed from the effluent for water reuse and chemical recovery. The process comprises a first dialysis system for salt removal, a second treatment system for recovery or re-concentration, and optionally a post-treatment of the re-concentrate preventing liquid discharges to the environment. In the first system, a reversible electrodialysis or reversible pulsed step is carried out, separating the salts from the effluent, which are sent to the second treatment system to concentrate the salts (re-concentrate) or transform them into useful chemicals for the same process (recovery). Chemical recovery is achieved by electrodialysis with bipolar membranes or metathesis, to reduce the re-concentrate stream, which cannot be reused in the same plant. Lastly, this stream may be treated by spray drying, crystallization or evaporation.

Disclosed are filter aids for use in industrial processes such as metal ore beneficiation dewatering and filtering processes, paper and pulp dewatering processes and sludge dewatering in municipal waste treatment. The filter aid provides increased filtering efficiency, and reduced filter cake moisture levels.

A process of extracting metals from a wet mass includes a step A of concentrating the metals in a carbonaceous solid with a thermochemical treatment of the wet mass, with the ancillary production of a treatment gas; a step B of thermochemical decomposition of the carbonaceous solid in an atmosphere constituted by an operating gas which contains oxygen in substoichiometric quantity to carry out the thermochemical decomposition in order to promote a combination of the metals with substances present in the carbonaceous solid to form salts and others solid compounds and to concentrate the latter in residual ashes of the carbonaceous solid at the same time providing for the formation of a combustible synthesis gas comprising hydrocarbons from the carbonaceous solid; and a step C of extraction of the metals from the ashes produced.

A method for processing a bark press water from sawmills and/or pulp mills is disclosed. According to the disclosure, the method comprises a) filtration of the bark press water to provide a bark press water filtrate having a particle size of less than 100 m, and b) concentrating the bark press water filtrate to a level of at least 10% dry weight and thereby providing a first fraction of concentrated bark press water, comprising tannic compounds; and a second fraction of purified bark press water.