A sludge dehydration method includes a recovery process of recovering specific material as a dewatering aid from sludge generated in a sewage treatment process and a dewatering process of performing solid-liquid separation on sludge in which the dewatering aid recovered in the recovery process and dewatering target sludge are mixed.

A biofilter irrigation system comprises a cylindrical vessel having a central axis, a media bed positioned within the vessel, a spray head system positioned above the media bed, the spray head system comprising a central hub positioned at the central axis of the vessel, at least one arm extending distally from the central hub toward a wall of the vessel and configured to rotate about the central axis, and a plurality of nozzles connected to the at least one arm. The biofilter irrigation system further comprises a fluid outlet positioned below the media bed.

Metal working fluid decontamination apparatus (10) includes: an intake arrangement (40) for metal working fluid (42); a pump (16) for providing, in use, flow pressure to the metal working fluid (42); a decontaminator (50) for reducing contamination in the metal working fluid (42); and an outlet arrangement (34) for the metal working fluid. The metal working fluid (42) is a fully synthetic metal working fluid, which comprises water and a water soluble synthetic concentrate which does not comprise oil.

A water purification apparatus (1) comprising a Reverse Osmosis, RO, device (26). The RO device (26) comprises a RO membrane (26a) and a feed pump (23). The apparatus (1) also comprises a recirculation mechanism (33) arranged to recirculate a portion of the reject water to the feed water, a temperature sensor device arranged to measure a temperature indicative of the temperature of the RO membrane (26a), and a flow rate sensor device arranged to measure a flow rate indicative of the permeate flow rate of the permeate water. The apparatus (1) further comprises a control arrangement (50) configured to control recirculation to achieve a predetermined recovery ratio. The control arrangement (50) is also configured to control the rate of the feed pump (23), based on the measured temperature indicative of the temperature of the RO membrane (26a) and a desired permeate conductivity, to make the permeate flow rate equal to, or within a predetermined margin of, an energy efficient permeate flow rate determined based on a predetermined relation between RO membrane temperature, permeate flow rate and permeate conductivity. The disclosure also related to a corresponding method.

Materials for binding per- and polyfluoroalkyl substances (PFAS) are disclosed. A fluidic device comprising the materials for detection and quantification of PFAS in a sample is disclosed. The fluidic device may be configured for multiplexed analyses. Also disclosed are methods for sorbing and remediating PFAS in a sample. The sample may be groundwater containing, or suspected of containing, one or more PFAS.

Provided is a method for predicting particulate breakthrough time for a non-regenerative ion exchange resin device, in which a portion of water to be treated by a non-regenerative ion exchange resin device passes through each of the following that are disposed in parallel with the non-regenerative ion exchange resin device: a first path that includes a first particle counter; a second path that includes a first compact resin column, a second particle counter, a flow rate regulating valve, and a first flow meter; and a third path that includes a second compact resin column, a third particle counter, a flow rate regulating valve, and a second flow meter.

According to one or more embodiments, sulfate ions may be removed from seawater to form an injection fluid by a method including passing the seawater and formation water to a mixing tank. The seawater may comprise sulfate ions. The formation water may comprise barium ions. The seawater and formation water may be passed to the mixing tank in a ratio determined by a computerized geochemical model. The method may further include mixing the seawater and formation water to form a mixed fluid and passing the mixed fluid to a clarifier, where a barium sulfate precipitate may be formed and at least a portion of the barium sulfate precipitate may be separated from the mixed fluid. The method may further include passing the mixed fluid to a microfiltration system, where at least a portion of the barium sulfate precipitate may be removed from the mixed fluid to form an injection fluid.

Systems and methods include a computer-implemented method for predicting pH of seawater. A model is generated that is configured to predict a power of hydrogen (pH) of treated seawater. Generating the model includes correlating process parameter values and historical data of seawater processing plants of oil and gas reservoirs. Upstream parameters of the seawater plant are received by a soft sensor pH predictor installed at a seawater plant. A pH of seawater being processed by the seawater plant is predicted using the model and neural network software of the soft sensor pH predictor.

A wastewater treatment apparatus includes a treatment mechanism that treats a wastewater containing an organic chromaticity component with an enzyme produced by Bacillus proteolyticus.

Infiltration system management and operation is provided using leading indicators. These leading indicators may be sensed at various locations and compared to a target value or range or other criteria when making adjustments to blower, vacuum, pump, or valve operation of an infiltration system. Other operational components or parameters may also be adjusted when considering one or more leading indicator. For instance, sacrificial carbon sources may also be added or replaced based on the status of a leading indicator and its comparison to a target value or range.