A system for treating metal-contaminated wastewater includes a primary treatment sub-system, a secondary treatment sub-system, and a tertiary treatment sub-system. The tertiary treatment sub-system includes a reactor tank, a source of ballast material, a source of coagulant, a solids-liquid separator, and a controller configured to recycle ballasted solids from the solids-liquid separator to the reactor tank an amount sufficient to generate metal hydroxide floc in the reactor tank to reduce a concentration of dissolved metal in the reactor tank.

The application belongs to the technical field of water treatment, and relates to a biofilm electrochemical reactor for simultaneously removing nitrate nitrogen and trace organic matters in water. According to the principles of electrochemical reaction and products completely different under different cathode and anode material conditions, the reactor is divided into three functional regions, wherein first, an electrochemical reaction of producing hydrogen at a cathode and decomposing carbon at an anode is realized in a first functional region so as to provide a condition for reduction of nitrate nitrogen by a hydrogen autotrophic denitrifying bacteria of a particle electrode layer in a second functional region, after products generated by means of the electrochemical reaction and a biochemical reaction in the previous two functional regions enter a third functional region, pollutants such as trace organic components and residual ammonia nitrogen in water are oxidized and decomposed by using anodic oxidation function.

[Problem] A carrier for retaining anammox bacteria, an anammox bacteria-adhered particle, and a wastewater treatment apparatus are provided that can remarkably reduce the start-up period for obtaining a nitrogen removal speed of 1 kg-N/m.sup.3/day. [Solution] A carrier for retaining anammox bacteria includes carbon particles. The carbon particles are desirably graphite particles, particularly isotropic graphite particles. The carbon particles desirably have a zeta potential of −35 mV to 0 mV and an average particle size of 2 μm to 1000 μm.

A method for enhancing biochemical water treatment by a powder carrier includes: (i) screening the powder carrier by removing impurities to obtain a screened powder carrier; (ii) dissolving the screened powder carrier by stirring to prepare a slurry, enabling the screened powder carrier to completely absorb moisture to obtain a soaked powder carrier slurry; (iii) adjusting the pH value and adding the soaked powder carrier slurry into a bioreactor or a biological reaction structure; (iv) distributing the soaked powder carrier slurry uniformly through a hydraulic agitation; (v) loading a microorganism on the inner pore and wrapping on the surface of the soaked powder carrier slurry to obtain powder-loaded biological floccules; (vi) settling the powder-loaded biological floccules in a sedimentation zone and separating the powder carrier from the microorganism for reuse.

The present inventors have developed systems and processes for reducing the overall carbon consumption needed for the generation of low COD treated water. In certain aspects, the systems and processes described herein include an oxidation stage (e.g., one that utilizes ozone, hydrogen peroxide, ultraviolet, or a combination thereof for oxidation) between a first activated carbon stage and a second activated carbon stage to reduce a total carbon consumption within the associated system or process.

A system for treating metal-contaminated wastewater includes a primary treatment sub-system, a secondary treatment sub-system, and a tertiary treatment sub-system. The tertiary treatment sub-system includes a reactor tank, a source of ballast material, a source of coagulant, a solids-liquid separator, and a controller configured to recycle ballasted solids from the solids-liquid separator to the reactor tank an amount sufficient to generate metal hydroxide floc in the reactor tank to reduce a concentration of dissolved metal in the reactor tank.

The present invention relates to a composite treatment and recovery technique of polluted water body and soil. Iron-rich straw biomass, after being crushed, is mixed and granulated with sludge, and is pyrolytic charred by programmed heating, to obtain bulk loaded zero-valent iron biochar and sludge biochar composite particles, which are packed as fillers in a filled bed or as filters in filter cells of a fixed bed, for effective recovery of complex polluted water, polluted by heavy metals, organics, nitrogen, phosphorus, and the like.

The present disclosure provides an urban river channel direct purification device. The device includes a support wall panel arranged vertically, an upper tray and a lower tray arranged horizontally, an upper end of the support wall panel is connected with the upper tray, a lower end of the support wall panel is connected with the lower tray, the upper tray and the lower tray are respectively semi-circular, several filler biological walls are disposed between the upper tray and the lower tray, a top end of each filler biological wall is fixedly connected with the bottom of the upper tray, a bottom end of each filler biological wall is fixedly connected with the lower tray, and the filler biological wall is arranged along a radial direction of the upper tray/lower tray. The device can purify the water of the river channel through the adsorption material in the device.

In some implementations, a method may include introducing into a contaminated media a suspension of a bioremediation composition. In addition, the method may include where the bioremediation composition may include a first bioremediation composition having a first blend of one or more electrolyte solutions capable of ionic conduction and a second bioremediation composition having a second blend of one or more active materials and being capable of electric conduction.

A system for treating metal-contaminated wastewater includes a primary treatment sub-system, a secondary treatment sub-system, and a tertiary treatment sub-system. The tertiary treatment sub-system includes a reactor tank, a source of ballast material, a source of coagulant, a solids-liquid separator, and a controller configured to recycle ballasted solids from the solids-liquid separator to the reactor tank an amount sufficient to generate metal hydroxide floc in the reactor tank to reduce a concentration of dissolved metal in the reactor tank.