The present invention is directed to an electrochemical device for at least partially removing or reducing a target ionic species from an aqueous solution using faradic immobilization, the electrochemical device including at least one first electrode and at least one second electrode with different void fraction and surface area properties, due to differences in void fraction (also referred to as void ratio) of the at least one first and the at least one second electrode, water flows through an electrode with a high porosity, while the aqueous solution does not flow through an electrode with a low porosity. The asymmetry of the electrodes provides a desired voltage distribution across the device, which equates to a different voltage at each electrode, to control the speciation of the target ionic species at the anode and the cathode.

The present disclosure relates to processes for treating wastewater such as acid rock drainage. The processes may, for example, comprise subjecting the wastewater to a microbial fuel cell process, neutralizing the acid with a base comprising calcium to produce an aqueous composition comprising calcium ions and subjecting the aqueous composition comprising calcium ions to a biological precipitation process to precipitate the calcium ions as calcium carbonate.

The present disclosure provides a method of preparing a carbonaceous material capable of fixing arsenic and an application thereof. Through biomass pretreatment, biomass pyrolysis and arsenite fixation, a biochar activated by potassium carbonate and an arsenic-containing wastewater containing sulfur-containing substances are mixed and deoxidized, and an anaerobic culture is carried out, to fix arsenic by the biochar activated by potassium carbonate. The present disclosure solves the problems that arsenic is released from the soil and groundwater under anaerobic conditions, the ability of conventional passivatingagents to fix arsenic under anaerobic conditions is weakened, and the conventional carbonaceous materials not only cannot fix arsenic, but also accelerate the release of anaerobic arsenic.

A stabilized, gas-infused liquids containing ultra high concentrations of infused gas, produced by: generating a gas-infused liquid in a sealed vessel under a high pressure of at least 20 psi; stabilizing the gas-infused liquid by passing the liquid while still under the high pressure through a tubular flow path arrangement which compresses the infused gas into nano bubbles in the liquid; infusing an additional amount of the gas into the stabilized liquid by injecting the same, while still under high pressure, back into the sealed pressure vessel along with more of the gas; and again stabilizing the liquid by again passing liquid, while still under the high pressure, through the tubular flow path arrangement to thereby form the additional amount of infused gas into nano bubbles in the liquid.

The present disclosure provides for a method of filtering pollutants from a contaminated fluid stream. The method includes disposing unprepared humic shale in a container, contacting the unprepared humic shale with an aqueous solution, maintaining the aqueous composition in contact with the unprepared humic shale for a period of time, drying the humic shale, and then placing polluted water in contact with the humic shale until pollutants have been removed from the fluid.

A method of treating a waste liquid: an aluminum dissolution step of dissolving aluminum in an acidic waste liquid and performing separation into a first treated water and a reduced heavy metal precipitate; a gypsum recovery step of adding a calcium compound to the first treated water at a pH of 4 or less, and performing separation into a second treated water and gypsum; a heavy metal coprecipitation step of adding a ferric compound to the second treated water and performing separation into a third treated water and a heavy metal coprecipitate; an aluminum and fluorine removal step of adding an alkali to the third treated water and performing separation into a fourth treated water and a precipitate containing aluminum and fluorine; and a neutralization step of adding an alkali to the fourth treated water and performing separation into an alkali neutralization treated water and a neutralized heavy metal hydroxide.

The instant invention, in one aspect, provides a process for decontaminating water to remove contaminants, said process comprising passing contaminated water through a filter comprising a plurality of filtering elements capable of lowering the contaminants by at least 70%. In another aspect is provides a filtering unit comprising a plurality of filtering elements arranged in individual layers, said individual layers independently selected from brick chips, hemp fibers, mixture of hemp fibers and charcoal, agave, jute fibers, sand, filter paper, and gravel.

Provided are electrodialysis systems comprising a plurality of electrodialysis devices, wherein each electrodialysis device of the plurality of electrodialysis devices has a product inlet stream, a product outlet stream, a brine inlet stream, and a brine outlet stream. The product inlet stream for a first electrodialysis device comprises the brine outlet stream of a second electrodialysis device. Further, a first portion of a feed stream is the brine inlet stream for the first electrodialysis device and a second portion of the feed stream is the brine inlet stream for the second electrodialysis device or a third electrodialysis device.

A filter for a water purifier includes a filter housing that defines an inlet and an outlet, and a filter module disposed inside the filter housing and configured to purify water received through the inlet and supply purified water to the outlet. The filter module includes a carbon block that includes a mixture of: activated carbon having a weight corresponding to 40 to 50% of a weight of the mixture, a binder having a weight corresponding to 5 to 15% of the weight of the mixture, iron hydroxide having a weight corresponding to 10 to 20% of the weight of the mixture, and titanium oxide having a weight corresponding to 30 to 40% of the weight of the mixture.

A method for processing a metallurgical waste acid, includes the following steps. First, a certain amount of a metallurgical waste acid is added into a reaction kettle. Then, the metallurgical waste acid and magnesium slag are added into the reaction kettle in a weight ratio ranging from 5:1 to 15:1 and are stirred into a mixed waste water. The reaction temperature is the room temperature. Then, a certain amount of sulfuric acid is added into the reaction kettle to control the mixed waste water within a pH range. At last, the mixed waste water is filtered.