Improved methods for the removal of heavy metals, in particular cadmium, from an aqueous phosphoric acid containing composition, wherein an organothiophosphorous heavy metal precipitating agent and an ionic polymeric surfactant, particularly a cationic polyacrylamide copolymer surfactant, are both added to a phosphoric acid containing composition, particularly under vigorous mixing conditions, such as between 500 and 700 rpm. The ionic polymeric surfactant promotes the precipitation of the heavy metals. More in particular, the phosphoric acid containing composition is obtained by the acid digestion of phosphate rock, preferably by nitric acid, sulfuric acid, or a combination thereof.

Methods and systems for treating oil sands tailings streams using multiple dosages of lime are disclosed herein. In some embodiments, the method comprises providing a tailings stream including 3-40% solids by total weight, combining the tailings stream with a first dosage of lime to produce a first mixture having a pH of less than 12.0, and then combining the first mixture with a polymer to produce a second mixture. In some embodiments, the method can further include combining the second mixture with a second dosage of lime to produce a third mixture having a pH greater than 12.0, and dewatering the third mixture in a centrifuge unit and/or a pressure filtration unit to produce a product stream having 55% or more solids by weight.

Disclosed is a method for recovering phosphorus from sludge rich in chemical phosphorus precipitates using a high-protein biomass waste, comprising introducing the sludge rich in chemical phosphorus precipitates into an anaerobic fermenter, adding a certain amount of a high-protein biomass by-product, sealing the fermenter and fermenting for 4-7 days. The method can effectively increase the phosphorus release efficiency from the sludge, and also generate volatile short-chain fatty acids and ammonia nitrogen in high concentrations. After dewatering, phosphorus and part of ammonia nitrogen can be recovered in a form of high-purity struvite crystals only by addition of a magnesium salt and adjustment of pH to 7.5-9.0. The volatile short-chain fatty acids can be used as an economical carbon source. The method allows simultaneous utilization of two solid wastes to recover carbon, nitrogen and phosphorus resources, and can reduce the usage of chemical reagents, saving the treatment cost.

Disclosed is a method for recovering phosphorus from sludge rich in chemical phosphorus precipitates using a high-protein biomass waste, comprising introducing the sludge rich in chemical phosphorus precipitates into an anaerobic fermenter, adding a certain amount of a high-protein biomass by-product, sealing the fermenter and fermenting for 4-7 days. The method can effectively increase the phosphorus release efficiency from the sludge, and also generate volatile short-chain fatty acids and ammonia nitrogen in high concentrations. After dewatering, phosphorus and part of ammonia nitrogen can be recovered in a form of high-purity struvite crystals only by addition of a magnesium salt and adjustment of pH to 7.5-9.0. The volatile short-chain fatty acids can be used as an economical carbon source. The method allows simultaneous utilization of two solid wastes to recover carbon, nitrogen and phosphorus resources, and can reduce the usage of chemical reagents, saving the treatment cost.

The present invention relates to a method for enhancing deep degradation of proteins in sludge. The method includes the following steps: an anaerobic digestion product of excess sludge as a substrate is treated by Van Soest's washing method to obtain the sludge free of easily degradable organics and containing degradation-resistant proteins; then, with the anaerobic digestion product of excess sludge as an inoculum and the sludge free of easily degradable organics and containing degradation-resistant proteins as a substrate, a first-stage microbial electrolytic cell coupled anaerobic digestion system is started for treatment to obtain a microbial mixture related to targeted degradation of the degradation-resistant proteins; with the microbial mixture related to targeted degradation of the degradation-resistant proteins as an inoculum and the anaerobic digestion product of excess sludge as a substrate, a second-stage microbial electrolytic cell coupled anaerobic digestion system is started to obtain the sludge with deeply degraded proteins.

A system for dewatering a material comprising a slitter, wherein the slitter receives the material, separates the material into a plurality of clumps, and deposits the plurality of clumps of material substantially evenly on a conveyor belt. The conveyor belt is partially porous to allow water to pass through but preventing material from passing through. The conveyor belt is operable to convey the material from the slitter to a compression zone; the compression zone comprises at least one high pressure press. The compression plates engages the material positioned on the conveyor belt. At least one knife positioned proximate the at least one compression plate operable to remove material from the bottom surface of the at least one compression plate after a compression cycle; and at least one drain positioned under the conveyor belt to carry water removed from the material away from the conveyor belt.

A method for quickly converting organic waste into energy, including the following steps of S1, performing anaerobic fermentation on organic waste to convert macromolecular organic matter in the organic waste into soluble small molecular organic matter to obtain fermentation liquid; S2, performing solid-liquid separation on the fermentation liquid to obtain a solid-phase part and a liquid-phase part, respectively; and S3, disposing or reusing the solid-phase part as residues, and enabling the liquid-phase part to enter a flow-catalyzed fuel cell to convert organic matter in the liquid-phase part into electrical energy. The present application can quickly and efficiently convert the organic waste into electrical energy.

The invention relates to a new biological fluidized bed process with high concentration powder carriers used for the treatment of municipal wastewater, which is a fluidized bed system based on the principle of sewage biochemical treatment, by adding a compound powder carrier to the biochemical tank, and forming a high concentration mixture after mixing and microbial attachment; the sludge mixture after the reaction is concentrated and separated, and then enters the compound powder carrier cyclone separation and recovery system, which can separate most of the compound powder carrier from the discharged excess sludge, and then return to the biochemical tank for recycling. The highly integrated municipal wastewater treatment process proposed in the invention has high treatment efficiency, small occupation area, low operation energy consumption, and can realize the doubling of sewage treatment capacity and the improvement of effluent water quality without adding additional occupancy.

A food processing system includes at least one receptacle containing a composition of water and insoluble solids, a centripetal force-based solid/liquid separator having an inlet, a solids outlet, and a liquid outlet, and a pump able to direct the composition from the receptacle to the inlet of the separator. The separator is configured to separate the composition into a solids stream including the insoluble solids and a liquid stream including water and to direct the solids stream through the solids outlet and the liquid stream through the liquid outlet.

A food processing system includes at least one receptacle containing a composition of water and insoluble solids, a centripetal force-based solid/liquid separator having an inlet, a solids outlet, and a liquid outlet, and a pump able to direct the composition from the receptacle to the inlet of the separator. The separator is configured to separate the composition into a solids stream including the insoluble solids and a liquid stream including water and to direct the solids stream through the solids outlet and the liquid stream through the liquid outlet.