Processes and apparatus are provided for recovery of dissolved species from wastewater streams, in the form of precipitates sized by elutriation. The processes may for example be controlled so that the recovered sized solids are in the form of relatively insoluble plant nutrients, such as struvite. The extracted nutrients may for example include solid species of phosphorus, and/or nitrogen, and/or potassium.

The invention relates to a method and an assembly for recovering magnesium ammonium phosphate from slurry supplied to a reaction container (10) in which an aerobic milieu that is alkaline as a result of CO.sub.2-stripping is present and in which the slurry is guided in a circuit with the aid of ventilation. Cationic magnesium, such as magnesium chloride, is added to the slurry, and magnesium ammonium phosphate crystals which are crystallized out of the slurry are removed via a removal device (30) provided in the base region of the reaction container. The slurry is supplied from the first reaction container (10) to a second reaction container (12) via a first line (14), wherein an anaerobic milieu is set in the second reaction container in order to redissolve the phosphate, and MAP crystals crystallized in the second reaction container are supplied to the first reaction container.

Various embodiments relate to methods and systems for removing phosphorus and/or nitrogen from water. A method of removing phosphorus and nitrogen from water includes passing starting material water including nitrogen and phosphorus through an elevated pH phosphorus removal stage. The method includes passing the water through an electrolytic nitrogen removal stage. The method includes passing the water through a galvanic phosphorus removal stage. The water produced by the method has a lower phosphorus concentration and a lower nitrogen concentration than the starting material water.

Various embodiments relate to an electrochemical cell for removal of materials from water and methods of using the same. A method of removing phosphorus from water includes immersing an electrochemical cell in water including phosphorus to form treated water including a salt that includes the phosphorus. The electrochemical cell includes an anode including Mg, Al, Fe, Zn, or a combination thereof, a cathode including Cu, Ni, Fe, or a combination thereof. The method includes separating the salt including the phosphorus from the treated water, to form separated water having a lower phosphorus concentration than the water including phosphorus.

Methods for removing polymers from treatment fluids for use in subterranean formations are provided. In one or more embodiments, the methods include providing a treatment fluid comprising an aqueous base fluid and a polymer comprising polyvinylpyrrolidone or a derivative thereof; and adding a precipitant to the treatment fluid to form a precipitate with at least a portion of the polymer.

The present invention relates to a method for recovering N, K, and P from liquid waste stream, preferably from a stream of urine, or from a stream comprising excreta (e.g. faeces, manure, digestate, fertilizer), or from (concentrated) wastewater, for example, municipal (e.g. sewage, septic) and/or industrial wastewater (e.g. food and feed industry, agriculture, mining, etc.); more preferably from urine, such as human or animal urine; most preferably from human urine.

Methods and systems are disclosed for optimization of coagulation and/or flocculation in a water treatment process. According to exemplary embodiments, samples are taken from an aqueous liquid and the samples are monitored with an imaging device to capture visual data of particles dispersed or suspended in the liquid. The particles are classified into particle types based on the visual data and a particle size distribution indication is computed for each classified particle type. The particle size distribution indication is then compared to a predetermined particle size distribution value, and in response to a difference detected, dosage of at least one coagulation and/or flocculation agent in the water treatment process can be adjusted.

The invention relates to a method for providing at least one input parameter of a sludge dewatering process of a wastewater treatment plant. The method comprises: obtaining data representing process and/or plant configuration data of said wastewater treatment plant; feeding at least part of the obtained data to at least one model formed at least by historical process and plant configuration data gathered from a plurality of wastewater treatment plants combined with properties of applied chemicals in said wastewater treatment plants; and predicting at least one input parameter and/or at least one output parameter of the sludge dewatering process by means of the at least one model for adjusting sludge dewatering process of said wastewater treatment plant. The invention relates also to a computing unit for performing at least partly the method.

The invention relates to a method and an assembly for recovering magnesium ammonium phosphate from slurry that is supplied to a reaction container (10) in which an aerobic milieu is present and in which the slurry is guided in a circuit with the aid of ventilation. Cationic magnesium, such as magnesium chloride, is added to the slurry, and magnesium ammonium phosphate crystals which are precipitated from the slurry are removed via a removal device (30) provided in the base region of the reaction container. Substances which contain magnesium ammonium phosphate crystals collected in the removal device (30) are loosened and/or rinsed.

According to present disclosure, there is disclosed an algae growth and cultivation system that provides a cost-efficient means of producing algae biomass as feedstock for algae-based products, such as, fertilizer, feed, biofuel manufacture, and desirably impacts, nutrient recovery from waste streams for valued byproducts production, recycle water, and alternative/renewable energy production. The system as discussed herein is an integrated systems approach to wastewater treatment, algal strains selection for byproducts production, and recycle of algal biomass-processing waste or additional algae harvested as feedstock for products such as fertilizer production. Embodiments of a system as discussed herein present an economically viable algae production system and process that allows algae-derived products such as fertilizer, feed, biofuels, etc. to compete with non-organic or petroleum products in the marketplace.