A method treats an aqueous system to inhibit growth of one or more micro-organisms therein and/or to reduce the number of live micro-organisms therein. The method includes adding treatment agents to an aqueous system wherein said treatment agents include (a) a phosphonium compound; and (b) a compound having formula: M(XO.sub.2).sub.n wherein: M is a Group I or Group II metal; X is a halogen; and n is 1 or 2.

A membrane sorbent is described, which comprises 1-6 wt % silicon carbide nanoparticles dispersed in a polymer matrix. The polymer matrix may comprise polysulfone and polyvinylpyrrolidone. The membrane sorbent is used for separating oil from a contaminated water mixture. The silicon carbide nanoparticles of the membrane sorbent may be made from rice husk ash.

The Fischer-Tropsch (FT) process creates significant amounts of water. The invention provides an aqueous composition comprising specified amounts of dissolved and suspended solids, low chemical oxygen demand and low chlorine demand, pH in the range of 6.5 to 8.0, where the aqueous composition comprises organic carbon derived from fossil sources.

Some implementations of the present disclosure prevent, reduce or at least slow equipment fouling using passivation as a treatment prior to contacting metallic components with hydrocarbon containing fluid, that is, an environment where fouling occurs. For example, one implementation includes a method of passivating heat exchangers in a SAGD process or system using the compositions and compounds of the present disclosure. The composition may be applied to a component prior to its first inclusion in an online system or following placing the system offline for maintenance. The composition may be used to treat metallic equipment surface(s), for example, via contacting them with a suspension or solution of the composition described herein, prior placing the system online. The method may further include treatment of the process fluid, for example, via injection or batch treatment of the composition with the compositions described herein into the process fluid.

The invention provides a process for treating waste water from an industrial process for producing propylene oxide, which comprises subjecting the waste water to a catalytic wet oxidation treatment comprising: feeding a stream comprising the waste water to a reactor; subjecting the stream comprising the waste water to an oxidation treatment in the presence of oxygen and a catalyst resulting in a treated stream; sending at least part of the treated stream to a separator wherein the treated stream is separated into a gas stream and a liquid stream; and recycling part of the liquid stream to the reactor.

A method for the oxidation of ethylene to form ethylene oxide which comprises treating an aqueous stream in a cycle water treatment unit containing an anion exchange resin to reduce the content of the impurities.

The present disclosure generally relates to compositions and uses of sulfidogenesis inhibitor compounds of Formulae 1 and 2 for preventing sulfidogenesis, i.e., the reduction reaction of a sulfur-containing compound by sulfur-utilizing prokaryotes that produce sulfide species such as hydrogen sulfide, during enhanced oil recovery processes. A method for inhibiting or decreasing microbial sulfide production by sulfur-utilizing prokaryotes includes addition of an effective amount of sulfidogenesis inhibitor compounds of Formulae 1 and 2 to the fluid that is injected into a sulfidogenic reservoir system during enhanced oil recovery. For example, the compounds can be used as sulfidogenesis inhibitors in a water injection system for use in a hydrocarbon extraction system or a hydrocarbon production system. Thus, these compositions can be effectively used as inhibitors of biogenic hydrogen sulfide generation in oilfield fluids.

A method for treating wastewater is disclosed. The method is useful in particular for treating wastewater that is generated from the process of drilling, hydraulic fracturing and/or cleaning a bore of an oil or natural gas well bore. The method may include performing cold lime softening of the wastewater to form waste salt flocs, filtration of waste salt flocs, ozonation of the filtrate from the filtration, and reverse osmosis of the filtrate to produce a purified permeate.

In a process for treating wastewater from a combined gasification and Fischer-Tropsch (F-T) process, feedstock derived from Municipal Solid Waste or the like is gasified in a reactor (R) and treated in a cleanup unit (C) which generates a first wastewater stream (1st WWT STREAM) containing salts and inorganic pollutants. The first wastewater stream is treated in a treatment unit (T1) to remove inorganic pollutants derived from the syngas. The treatment comprises a) degassing, and subsequently b) neutralising the first wastewater stream before treatment in a Dissolved Air Flotation unit (72c) and filtering in a moving sand bed or similar (72d) to remove solids, and a stripping process to remove ammonia. A second wastewater stream (2.sup.nd WWT Stream) containing organic pollutants but being low in salts arises from the F-T process and is treated separately to allow recycling within the F-T process.

Methods for clarifying water, reducing turbidity of water, and removing phosphate from water include adding a water treatment composition having an aluminum-containing coagulant, and a natural non-charged polysaccharide, such as guar. The aluminum-containing compound can include polyaluminum chloride, aluminum chlorohydrate, polyaluminum chlorohydrate, aluminum sulfate, sodium aluminate, polyaluminum sulfate, polyaluminum silicate chloride, polyaluminum silicate sulfate, or a combination thereof.