A biodegradable iron-crosslinked alginate is useful as a remediation agent for environmental contaminants such as phosphate. When charged with phosphate, or other nutrients, the iron-functionalized alginate can be used as an agricultural fertilizer.

Methods for removing particulates from an aqueous suspension are provided. In at least one specific embodiment, the method can include mixing a polyamidoamine-epihalohydrin resin with an aqueous suspension comprising one or more first particulates to produce a treated mixture. An amount of the polyamidoamine-epihalohydrin resin in the treated mixture can be less than 500 g/tonne of the one or more first particulates. The method can also include recovering from the treated mixture a purified water having a reduced concentration of the one or more first particulates relative to the aqueous suspension, a purified first particulate product having a reduced concentration of water relative to the aqueous suspension, or both.

Known phosphorus recovery methods from liquid phases proceed from the presence of ammonia or nitrate, and phosphate, in the liquid phase. Wastewater that is supposed to be freed of nitrate and phosphate pollution in sewage treatment facilities can be used as the liquid phase. In electrochemical methods, a magnesium electrode is used as a sacrificial anode, and ammonium and phosphate together are bound to the magnesium to form struvite, which in turn can be used in agriculture as a fertilizer, in useful manner. In an alternative method of procedure, first, only phosphates are removed from a liquid phase that occurs from the filtration of products of hydrothermal carbonization. A magnesium electrode is used as the cathode, so that the resulting magnesium phosphate does not go into solution and first must be precipitated, but rather is removed from the electrolysis cell directly with the cathode, after the reaction occurs.

Various methods and systems are provided for electrokinetic dewatering of suspensions such as, e.g., phosphatic clay. In one example, among others, a system for continuous dewatering includes a cake formation zone including a first anode and a first cathode each extending across a first portion of a separation chamber; a cake dewatering zone including a second anode and a second cathode; an inlet configured to supply a dilute feed suspension comprising solids suspended in water to the cake formation zone; and a conveying belt extending between the first anode and the first cathode and between the second anode and the second cathode. A first electric field between the first anode and the first cathode forms a cake on the conveying belt by consolidating the solids, and a second electric field between the second anode and the second cathode dewaters the cake on the conveying belt.

Embodiments of the present disclosure are directed towards methods for preparing mixed-metal oxide particles by heating adamantane-intercalated layered double-hydroxide (LDH) particles at a reaction temperature of from 400° C. to 800° C. to form mixed-metal oxide particles. The adamantane-intercalated LDH particles have a general formula [M.sub.1-xAl.sub.x(OH).sub.2](A).sub.x.mH.sub.2O, where x is from 0.14 to 0.33, m is from 0.33 to 0.50, M is chosen from Mg, Ca, Co, Ni, Cu, or Zn, and A is adamantane carboxylate, and an aspect ratio greater than 100. The aspect ratio is defined by the width of an adamantane-intercalated LDH particle divided by the thickness of the adamantane-intercalated LDH particle. The mixed-metal oxide particles comprise a mixed-metal oxide phase containing M, Al or Fe, and carbon.

The present invention relates to a calcined diatomite aggregate coated with metal oxides, more specifically to a diatomite aggregate having a diameter larger than 2 mm.

A method for removing phosphorus by gasification, the method including: a) providing a membrane bioreactor including a reaction tank and a membrane separation system; b) aerating the reaction tank to control a redox potential in the reaction tank to be higher than −200 mV; and c) controlling the dissolved oxygen concentration around the membrane separation system to be greater than 0 and smaller than 2 mg/L and the dissolved oxygen concentration in the reaction tank excluding the membrane separation system to be greater than 0 and smaller than 1 mg/L, and allowing the dissolved oxygen concentration around the membrane separation system to be higher than the dissolved oxygen concentration in the rest zones of the reaction tank. A phosphorus removal system by gasification includes: a reaction tank, a membrane separation system, a water production system, an aeration system.

A method of wastewater treatment using a membrane bioreactor, including: controlling aeration to enable a dissolved oxygen concentration to be 0 to 1.5 mg/L, and keeping the integrated reaction vessel under a facultative environment. A wastewater treatment system by the membrane bioreactor without physical area division includes a reaction vessel, a membrane separation system, a water production system, and an aeration system. The membrane separation system is disposed inside the reaction vessel. The water production system communicates with the membrane separation system to pump filtrate out of the membrane separation system. The aeration system is employed to aerate the reaction vessel and the membrane separation system.

The present invention relates to a method for sludge safe disposal and resource recovery through sludge liquefaction and stratification. The method is to completely liquefy the organic matters in the sludge into soluble organic matters through a thermal-alkaline synergistic treatment. After the treatment, the sludge is stratified, and an anaerobic digestion is performed on a high-concentration soluble liquid of an upper layer to convert organic carbon, nitrogen and phosphorus into biogas, ammonia nitrogen and phosphate, a crude protein recovery is performed on a sludge protein of a middle layer, and a dewatering and a landfill on a sludge inorganic solid of a lower layer.

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.