Abstract: A counter top water filter unit intended for domestic use to be placed adjacent to a sink and having an inlet at its lower end which is coupled to the sink faucet through a swivelly mounted 90 degree elbow capable of 360 degree rotation so as to facilitate the coupling of the filter to the faucet from either side. The filter unit includes a cylindrical-shaped carbon particle filter cartridge which has a longitudinal passage extending from one end to the other, and a removable pre-filter screen coaxial with the cartridge and surrounding the cartridge, both elements being removably mounted within a cylindrical filter housing, the housing being closed at its upper end and open at its lower end.

Abstract: A fish-excluding, self cleaning screen forming at least part of the boundary between a body of water such as a stream, and a bay from which water is to be withdrawn. On the bay side of the screen is a hub with a plurality of rotating wands that discharge water against the bay side of the screen to flush screen apertures and provide a periodic variation in flow through the screen to discourage passage of fish. Optional brushes may periodically brush the bay side of the screen to assist in cleaning the apertures.

Abstract: Anaerobic digestion of wastewaters can be made more effective by introducing propane gas from an external source therein in order that the propane gas strips gas produced by the anaerobic digestion (e.g., methane, carbon dioxide, etc.) from the biomass system.

Abstract: Grating module for peripheral gutter for discharging overflow water from a swimming pool, which comprises a bendable, central longitudinal rib acting as a link for at least one transverse central rib arranged as a ridge on either side of this central rib, the said transverse rib being provided on its upper part with perpendicular slats projecting outwards and constituting the plantar span of the grating.

Abstract: A process for biologically removing nitrogen and other nutrients from wastewater using recycled activated sludge. A mixed liquor is formed from influent wastewater and recycled activated sludge and then treated in two successive nitrogen removal stages, each stage having an anoxic denitrification zone and an aerobic nitrification zone. The first nitrogen removal stage entails circulating the mixed liquor back and forth between the anoxic zone and the aerobic zone. The mixed liquor is then transferred to a final clarifier where activated sludge is separated from purified supernatant. To increase the NO.sub.x.sup.- reducing enzymatic activity of denitrification microorganisms, the activated sludge is retained in the final clarifier for a time period sufficient to permit adaptation of these microorganisms to a nitrate/nitrite-respiring metabolic pathway.

Abstract: A process and a device for biologically treating an organic waste mixture containing organically polluted waste water and solid components. The process and the device involve exposing the organic waste mixture to a first decomposition stage where the solid components and the waste water are separated from one another and where the solid components are decomposed under predominantly aerobic conditions. The waste water is then passed to a second decomposition stage where the waste water is decomposed under anoxic conditions. Thereafter, the waste water is passed to a third decomposition stage where the waste water is decomposed again under aerobic conditions thereby creating recirculation water. At least a portion of the recirculation water is returned from the third decomposition stage to the first decomposition stage for continuously recirculating water through and between respective decomposition stages.

Abstract: Process for the treatment of liquid effluents, such as waste water, for the purpose of removal of carbon, nitrogen and phosphorus pollution using an activated sludge, according to which the effluent, after having been subjected to mechanical pretreatments, is brought into contact with the activated sludge. The effluent/activated sludge mixture is the subjected to clarification/settling in order to separate the treated water from the thickened sludge, the latter then being recycled at the head of the aeration treatment and the excess sludge being continuously discharged. An inert material of inorganic origin is injected into the activated sludge, this material being immediately and homogeneously dispersed in the activated sludge, in order to create a mixed culture containing both, and in a single bacterial floc, free heterotrophic species and autotrophic species partially fixed on the particles of the said material within the floc.

Abstract: A process for treating a waste sludge of biological solids including the steps of mixing the sludge with an oxide-containing chemical and sulfamic acid so as to elevate a temperature of the sludge, pressurizing the mixed sludge to a pressure of greater than 14.7 p.s.i.a., and discharging the pressurized mixed sludge. The oxide-containing chemical can be either calcium oxide, potassium oxide, or potassium hydroxide. The sludge has a water content of between 5 and 85 percent. The oxide-containing chemical and the acid are reacted with the sludge so as to elevate the temperature of the sludge to between 50.degree. C. and 450.degree. C. The pressurized mixed sludge is flashed across a restricting orifice or passed into a chamber having a lower pressure. The evaporated liquid component can be condensed and used as part of the process. The oxide-containing chemical is mixed with the sludge in an amount between 5 and 50 weight percent of the sludge.

Abstract: An aquarium filter for removing chemical and physical waste from an aquarium. The filter includes a fluidized bed of particles, such as sand, for removing ammonia from the water. The filter can also include a physical trap for solid material and activated charcoal for removing organic material from the aquarium water. The filter can be constructed in an aesthetically desirable manner and can be convenient to maintain.

Abstract: A filter for removing particulate matter from water flowing into an inlet, such as a catch basin is disclosed. The filter may comprise an envelope of filter material adapted to receive an inlet cover device, such as a catch basin grate. The inlet device may be inserted within the envelope and placed in an opening of the inlet. Water, for example, may then be double filtered before entering the inlet. A roll filter comprising porous material is also disclosed that may be used in combination or alone when filtering runoff entering a curb drain or other inlet.

Abstract: The filter device (10), provided for the filtration of fluids, comprises two interconnected material structures (14,16) forming a filter unit (12). The two material structures (14,16) are mechanically stable, at least one of the two material structures (14,16) being elastically deformable. The two material structures (14,16) are connected to each other at opposite connecting sites, with one (16) of the material structures forming an arch between the connecting sites. This arch has been generated by elastic deformation of the respective material structure (16) so that this material structure (16) is mechanically biased. A stretching movement of this material structure (16) is prevented by the connection of this material structure (16) to the other material structure (14) which in turn is of substantially plane configuration and is tensioned.

Abstract: A device for filtering and refining oil being cycled through an engine includes a container, a cover having an evaporator plate incorporated therein, and a filter cartridge. The evaporator plate is dimensioned to conform to a predetermined inner shape of the container to sealably fit therein inhibiting the purified oil to cycle back through the filter. The configuration is such that a predetermined amount of oil is directed into the device and first passes through the filter cartridge and then passes over the evaporator plate. The contaminants evaporated from the oil pass through a vent in the cover. The filtered and refined oil is then directed back into the engine.

Abstract: A method for filtering edible oils utilizing a backwashable filter assembly. A filter system having at least two filter assemblies may be utilized to remove bleaching clay and/or nickel catalyst from oil being processed for human consumption. The filter assemblies may be connected in a series and tandem manner to provide continuous and uninterrupted filtering of the edible oil. Each filter assembly preferably comprises multiple, substantially cylindrical filter elements having a porous filter medium which may be formed from polyaramid fibers. The filter elements are designed to withstand the elevated temperatures used in edible oil processing and for ease of cleaning during backwashing.

Abstract: Methods and apparatus for treating waste streams utilize controlled introduction of microscopic gaseous bubbles to create, in a single vessel, as many as three separate biological environments in discrete, stratified zones. In preferred embodiments, bubbles of air are introduced at the bottom of the vessel, creating an aerobic zone in this vicinity. Depletion of oxygen by microorganisms resident in this layer creates an anoxic zone that drifts upward, establishing itself above the aerobic layer. The two layers remain segregated due to the intolerance of aerobic microorganisms for the overlying anoxic environment, the sharpness of the interface depending on the degree of intolerance.

Abstract: Waste water is reclaimed for reuse by combined use of settling tanks, ozonation and filtration. The settling tanks remove substantial solid matter from the waste water. The waste water from the last settling tank is treated with ozone to remove contaminants and purify the water. This ozonated water is then returned to the last settling tank to mix with the waste water. This ozonated water in the last tank is then subjected to a plurality of filtering actions before being stored in a clean water holding tank. Partially treated water or discharge from filters is returned to a different holding tank to mix with waste water and dilute the waste water.

Abstract: An activated sludge treatment process and apparatus are provided for denitrification of a trickling filter plant effluent in which the nitrate nitrogen to BOD5 ratio can be maintained at less than or equal to 0.18 without the use of a nitrate monitor to control supplemental dosing with carbonaceous organic compounds or their salts. The apparatus is equipped with a turbidity meter, a phosphate monitor, and with a substrate storage tank for the addition of carbonaceous organic substrate. The substrate is added immediately at the end of the oxic phase and is continued until phosphate release is detected. Accordingly, the phosphate monitor functions as an indicator of nitrate respiration in the anoxic phase.

Abstract: A process for use in the final stages of purification of sewage water in which the effluent is placed under pressure by a pump and forced through a filter. Part of the effluent is sampled and chlorinated by a chlorine gas injector and then reintroduced into the lager body of effluent. The entire mixture is held within a detention chamber in order to allow the chlorine to dissipate, and then pumped out into a natural stream through a pipe in which air bubbles are injected in order to replenish the oxygen level.

Abstract: An apparatus is disclosed for the disinfection of a liquid medium having a transmission of <75%/cm with the help of UV radiation. The apparatus comprises a plurality of UV radiators combined to a modular UV irradiation battery around which flows the liquid medium to be disinfected. Each UV radiator is oriented in parallel relationship to the flow direction of the liquid medium to be disinfected. The UV radiators are arranged in a matrix like array, particularly in a plurality of rows, each second row of said plurality of rows of UV radiators being offset with reference to the two adjacent rows by an amount corresponding essentially to half the center distance between two adjacent UV radiators located in the same row. The UV irradiation battery is enclosed by an essentially tube shaped housing, the inner contour of the housing essentially corresponding to the outer contour of the UV radiator battery.

Abstract: A method of regulating aeration in biological treatment of wastewater by implementing a step of eliminating carbon in aerobiosis, a step of nitrification in aerobiosis, and a step of denitrification in an anoxia, in which method the oxidation-reduction potential is continuously measured in a treatment system, a curve is established of variation in oxidation-reduction potential as a function of time, and the derivative thereof is calculated, wherein, when the derivative tends towards zero, the derivative and the value of the oxidation-reduction potential are correlated to determine whether aeration should be started, continued, or stopped.

Abstract: An in-well system for simultaneously treating and extracting groundwater by injecting compressed gas through the groundwater in multiple successive stages as it is pumped out of a well. The process is usable for in-well aeration stripping of Volatile Organic Compounds from groundwater or for other applications in which it is desirable to pass compressed gas through groundwater to alter the physical, chemical, or radiological properties of the groundwater prior to its discharge from the well.