A method for enhancing in situ bioremediation of a volume containing groundwater and a quantity of contaminant, the method comprising the steps of: quantifying the mass of the contaminant; and amending the volume by adding thereto a compound that provides a source of NO.sub.3.sup.−. The method is characterized in that the compound is added such that the mass of the NO.sub.3.sup.− source is provided at the ratio of about 1 mg NO.sub.3.sup.− per 0.21 mg contaminant. The contaminant can be BTEX or petroleum-related VOC.

The inventive subject matter disclosed herein includes multiple novel filter media made of activated rice husks, as well as filtration systems and methods for removing contaminants from an aqueous solution, such as wastewater produced as a byproduct of various industrial processes, including mining, oil and gas exploration and extraction, farming, manufacturing, and the like.

The present invention provides a process for working up alkaline waste water which is formed during washing of crude nitrobenzene obtained by nitration of benzene, wherein (i) the alkaline waste water is heated to a temperature of from 150° C. to 500° C. under an increased pressure with respect to atmospheric pressure with exclusion of oxygen; (ii) a base is added to the waste water obtained in (i); and (iii) the waste water obtained in (ii) is purified further by stripping with a stripping gas and the stripping gas stream loaded with impurities is then cooled to a temperature of from 10° C. to 60° C.

The invention relates to a process for working up alkaline waste water which is formed during washing of crude nitrobenzene obtained by nitration of benzene, wherein (i) the alkaline waste water is heated under an increased pressure with respect to atmospheric pressure with exclusion of oxygen and is then cooled and expanded; (ii) the waste water obtained in (i) is purified further by stripping with a stripping gas and the stripping gas stream loaded with impurities is then cooled to a temperature of from 10° C. to 60° C.; and (iii) the liquid process product obtained in (ii) by cooling the stripping gas stream loaded with impurities is separated into an aqueous and an organic phase and the organic phase is used further in an aniline production process.

Apparatus for removing suspended impurities from a liquid (e.g., wastewater), methods of use, and systems including such apparatus. In an embodiment, an apparatus may include a vessel defining a chamber for receiving gas induced liquid influent through an inlet, the influent including suspended impurities. A riser tube may be provided within the vessel, in fluid communication with the inlet so that liquid influent introduced into the vessel through the inlet is introduced into the riser tube. One or more coalescing members may be disposed within the riser tube. The coalescing members may be sufficiently small to be easily removable by hand, without requiring a crane. The coalescing members may be freely disposed within the riser tube, rotatable within the flow of the liquid influent, aiding the coalescing members in exhibiting some degree of “self-cleaning”, so as to be less prone to fouling and clogging.

The present invention discloses a process and a composition for the treatment of wastewater. The composition comprises of microbes, enzymes and cofactors along with the nutrients. The composition is a synergistic composition and wastewater can be treated effectively for the removal of pollutants by using the synergistic composition.

A produced water evaporation system for spray evaporating water comprising a geothermal heat retainment system and an evaporation system is disclosed. The geothermal heat retainment system comprises a first feed inlet, an optional solar collection system or a heat exchanger, and a first discharge outlet. The evaporation system comprises a second feed inlet, a pump, a drip manifold comprising a drip orifice or a manifold comprising a nozzle, a container, wherein a first portion of a ceiling of the container is constituted by a demister element such that the first portion of the ceiling is entirely configured as an outlet for evaporated water and wherein a second portion of the ceiling is adjacent to an upper edge of a wall of the container, a second discharge outlet, and an air system comprising an air blower and an optional air preheater, wherein the air system is disposed through the wall of the container and wherein the air system discharges air flow counter to the produced water and/or water droplets from the drip orifice. A method of using the produced water evaporation system is also disclosed.

The invention is a high-salt waste water air powered low temperature evaporating device and method of use. A tray is mounted on a lifting platform; an air inlet and a water inlet are on the tray. Air distributing pipes are arranged at the center of the nested column tubes (33). A groove (4) is installed at the top of the tray, and mounting points are accompanied by multiple nested column tubes (33). The nested column tubes (33) are connected with the air inlet. An atomizer is arranged inside the air distributing pipes; and the atomizer is connected with the water distributing pipes. Using air power evaporates concentrated waste water multiple times so that the salt in the wastewater reaches saturated concentration, and therefore, the wastewater temperature is reduced, salt is crystallized and separated out, liquid is continuously evaporated, and the wastewater can be completely treated.

Described herein is a method for purging paint circuits coated with a non-cured paint with improved cleaning efficiency and a reduced COD (Chemical Oxygen Demand) in the wastewater, where a paint circuit is brought into contact with a waterborne purge cleaner solution including at least one glycolether and which additionally includes at least one water-soluble amine having at least 7 carbon atoms. Also described herein is a waterborne purge cleaner solution with improved cleaning efficiency and reduced VOC (Volatile Organic Compound) content as well as a concentrate for producing the purge cleaner solution.

Processes and systems for treating Kraft pulping foul condensate are provided. The processes comprise removing volatile compounds from the foul condensate to produce a resulting condensate and removing methanol from the resulting condensate. The systems comprise a volatile compound removal stage and a methanol removal stage downstream of and in fluid communication with the volatile removal stage.