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.

A method for removing soluble and/or colloidal Si-compounds from an aqueous stream of a minerals processing plant is provided. The method includes adding coagulant(s) and/or flocculant(s) and/or flotation chemical(s) to the aqueous stream in order to facilitate formation of flocs comprising at least some of the Si-compounds, and in order to form a treated aqueous stream, subjecting the treated aqueous stream to cleaning flotation in order to separate at least some of the Si-compounds as a cleaning flotation overflow, and removing the cleaning flotation overflow. The cleaning flotation comprises gas bubbles, at least 90% of the gas bubbles having a diameter of from 0.2 to 250 μm.

A method includes supplying a supersaturated brine stream having a plurality of minerals and anti-scalant from a water treatment system to a gypsum removal system disposed within a mineral removal system. The gypsum removal system includes a gypsum reactor that may receive the supersaturated brine, may deactivate the anti-scalant such that gypsum precipitates from the supersaturated brine, and may generate a gypsum slurry having a mixture of desupersaturated brine, precipitated gypsum, and the anti-scalant in solution with the desupersaturated brine. The method also includes supplying gypsum seed crystals to the gypsum reactor. The gypsum seed crystals may precipitate the gypsum from the supersaturated brine to generate the gypsum slurry. The method also includes directing a first portion of the gypsum slurry from the gypsum reactor to a gypsum settler. The gypsum settler may reactivate the anti-scalant such that the anti-scalant absorbs onto the precipitated gypsum to remove the anti-scalant from the desupersaturated brine and may generate anti-scalant-gypsum crystals and a desupersaturated overflow having at least a portion of the plurality of minerals. The method further includes generating the gypsum seed crystals supplied to the gypsum reactor using the anti-scalant-gypsum crystals.

An extrusion system for separating particulates entrained in wash water, e.g. from harvesting tuberous produce, includes a settling tank configured to receive a flow of particulated water. A diffuser suspended within the tank converts the flow of particulated water into multiple transverse flows to avoid churning settled particulates. A particulate filter fixed within the tank includes a central channel surrounded by a cylindrical array of cantilevered parallel vertical blades. The channel directs the flows below the blades, causing dynamic movement of the blades as the particulated water rises therebetween to trap particulates along boundary layers, promote particulate settling by gravity, and allow clarified water to rise to the top of the tank. A sensor detects settled particulate reaching a predetermined setpoint, and in response the system actuates an auger and opens a pinch valve to force concentrated particulate from the bottom of the tank.

The present invention is directed to a clarifier for water treatment including a module. The module includes a planar inclined sheet; a plurality of vertically-oriented supports; and a tensioner. The at least one planar inclined sheet is tensioned between the plurality of vertically-oriented supports and the tensioner is configured to bring the planar inclined sheet to an even centerline.

Methods and systems for removing pollutants from water include one or more filter systems and a hybrid wetland system. Hybrid wetland systems may include a first pipe transporting water from a body of water to a settling tank, a first constructed wetland connected to the settling tank via a second pipe, and a first filter system removing pollutants from water passing through the second pipe. A second filter system is positioned within the first wetland to further remove pollutants. The system also includes a second constructed wetland connected to the first constructed wetland via a third pipe and a water control chamber. Filtered water exiting the first constructed wetland flows through the water control chamber, through the third pipe, and into the second constructed wetland. A fourth pipe extends between the second constructed wetland and the body of water, returning filtered water to the body of water.

Methods for removing a soluble heavy metal-sulfur complex from a process solution comprise contacting the process solution with an oxidant to oxidize the heavy metal-sulfur complex and form an oxidized complex precipitate, or with an acid to acidify the heavy metal-sulfur complex and form an acidified complex precipitate, and removing the precipitate from the process solution to provide a heavy metal-reduced solution. The method is advantageous for removing heavy metals such as mercury, cadmium, barium, iron, vanadium and/or manganese from process solutions, for example originating from natural gas production, petroleum production, water treatment or mining.

A passive filter cell having a basin with a floor and two or more vertical or upright sidewalls forming chute or container having first or left sidewall, second or right sidewall, and third or back sidewall, and fourth or front downwardly curved sidewall, an inlet positioned proximate a top of the fourth or front sidewall and an outlet positioned proximate the top of the third or back sidewall, wherein the floor is configured angled from the fourth or front sidewall to the third or back sidewall, discharge pipe positioned proximate junction between the floor and the third or back sidewall, and lip configured to extend from the top of the third or back sidewall into an interior of the basin.

Settling devices for separating particles from a bulk fluid with applications in numerous fields. The particle settling devices include a stack of cones with a small opening oriented upwardly or downwardly. The cones have an interior surface that is convex. These devices are useful for separating small (millimeter or micron sized) particles from a bulk fluid with applications in numerous fields, such as biological (microbial, mammalian, plant, insect or algal) cell cultures, solid catalyst particle separation from a liquid or gas and waste-water treatment.

A separation device configured to separate light and heavy components of an effluent mixture. The separation device includes a separation tank, an inlet discharge, an outlet diffuser, and a baffle. The separation tank includes a tank reservoir for containing the effluent mixture during separation, with light components configured to migrate upwardly toward a static water line and heavy components configured to sink adjacent the bottom. The inlet discharge is located within the tank reservoir to supply effluent mixture to the separation tank. The outlet diffuser is spaced from the inlet discharge and located within the tank reservoir to receive a heavy component of the effluent mixture after separation. The baffle is located within the tank reservoir to separate the inlet discharge from the outlet diffuser. The baffle presents a baffle opening adjacent the static water line.