Abstract:
An improved method for maintaining a granular medium filter in a clean, operable condition is disclosed. The time interval required for the level of liquid above the filter bed to drain from a backwash outlet level to the upper bed surface level following a backwash cycle is monitored. Upon this measured draindown time exceeding a predetermined interval of time, a chemical cleaning cycle is initiated for the granular medium bed filter.
Abstract:
Filter pads, which are made inherently stable by binders and by removal of the binders can be converted in packings to be maintained under substantially constant surface pressure between rigid filter brackets, are produced first as molded bodies from a suspension of filter aids in liquid by depositing granular, fibrous, or fiber-containing filter aids or mixtures of those filter aids in a casting mold, there being used high rates of flow while avoiding turbulences, and adding binders to the suspension so that the molded body can be stabilized by activation of the binder while drying. It is possible in this process also to manufacture multi-layered filter pads, it having been surprisingly found in those multi-layered filter pads that the layer assembly is kept intact during the filtration even in the filter packing that no longer contains binders. The filter pads or the filter packings produced therefrom according to the invention can, when used, and after reflushing and regeneration operations, finally be utilized, after being replaced, as filter aids in the deposit filtration process.
Abstract:
A process and apparatus for protecting a media bed filter with underlying support screen from solids contained in a liquid, such as filtrate from the filter, used to regenerate or backwash the media bed filter. Filtrate enters a first collection chamber containing a screen assembly covering one outlet, the chamber also containing a second outlet. Filtrate traverses the screen assembly and is transferred to a second collection chamber with addition of a predetermined amount of bactericide to prevent solids growth therein. Upon bactericide-treated filtrate reaching a predetermined level within the second chamber, filtrate in the first chamber bypasses the screen assembly and flows out the second output to further biological treatment or use. Bactericide-treated filtrate from the second collection chamber is used to regenerate or backwash the media bed filter with addition of optional surfactant to assist in cleaning the filter media and underlying support screen. The first collection chamber has an alarm system which detects resistance of filtrate flow traversing the screen assembly and warns that the screen assembly requires cleaning or replacement, thus fully protecting the support screen from solids.
Abstract:
Gas bubbles, and in particular nitrogen gas bubbles, generated during the denitrification of treated wastewater in a deep-bed filter are removed by venting them from a level below the surface of the filter bed. Gas removal may be enhanced by introducing pressurized air or water into the lower portion of the filter bed to dislodge the gas bubbles from the filter media and drive them upward where they can be vented to the atmosphere. Alternatively, pressurized air or water may be introduced into a vent pipe located below the surface of the filter bed to drive the gas bubbles up through the surface of the filter bed.
Abstract:
A system and a method for filtering a predetermined molecule entrained as a 3D-complex in a liquid comprising a filter forming solid all forming a filter forming suspension, the system having a filter chamber into which the filter forming suspension is fed and drained to form a filter with inclusions of the 3D-complex, where after a cleansing liquid is fed to a neighbouring liquid chamber and fed evenly through the filter to cleanse the filter and subsequently dissolve the complex to retrieve the product or target molecule.
Abstract:
A filtration apparatus is provided. The filtration apparatus includes a housing and a plurality of filtering sheets. The housing is enclosed by a first end cap and a second end cap. The first end cap includes a liquid inlet, and the second end cap includes a liquid outlet. The plurality of filtering sheets is disposed on an internal sidewall of the housing. A portion of the filtering sheets interlaces with another portion of the filtering sheets to form a winding flow path in the housing.
Abstract:
A milking device for milking a dairy animal is provided with milking mechanism, a control system, a milk pipeline for transporting the milk from the milking mechanism to a milk tank, a milk filter and a cleaning device. The cleaning device includes at least one cleaning fluid holder, a heating device for heating cleaning fluid in the cleaning fluid holder, an additive storage holder for additive, an additive adding device for controlled addition of the additive to cleaning fluid, and a valve system for regulating flows of cleaning fluid and additive through the milking device. The cleaning device is configured for carrying out a cleaning cycle of the milking device with a prerinse with cold or tepid water, a hot rinse with heated water and an acidic or basic additive, a postrinse, and at least between the hot rinse and the postrinse, a counterflow cleaning step by passing cleaning fluid in counterflow through the milk filter. Thus, a milking device is provided that can be cleaned automatically as a whole including the milk filter. In particular, because the counterflow cleansing takes place after the hot rinse step, there is better removal of dirt and milk residues that are softened thereby, in particular from the milk filter.
Abstract:
Systems and methods for processing produced water containing organic compounds include a processing vessel; a filtration layer including a filtration material; and a cleaning system that provides a washing solution to the filtration material during a cleaning cycle. The filtration layer is configured such that at least a portion of produced water that enters the processing vessel during a processing cycle of the processing system passes through the filtration layer before leaving the processing vessel. The filtration material is a metal compound such as a metal hydroxide or a metal oxohydroxide that is substantially insoluble in aqueous solution. The washing solution includes a reagent capable of reducing the metal compound to a reduced compound soluble in aqueous solution while not decomposing the organic compounds. The organic compounds such as crude oil may be recovered from the filtration layer material after the cleaning cycle, and the filtration layer may be regenerated.
Abstract:
Methods of combined sterilization and integrity testing of dialyzers such as hollow fiber dialyzers are disclosed. Sterilization and integrity testing may be performed by treating the dialyzer with a sterilization fluid for sterilizing at least the blood-side compartment of the dialyzer and for wetting the dialysis membrane of the dialyzer with the sterilization fluid, and carrying out an integrity testing of the dialysis membrane wetted with the sterilization fluid, wherein the sterilization fluid is selected from aqueous solutions containing peroxide and/or ozone, the peroxide being selected from peroxides which disintegrate into water, oxygen and/or volatile organic compounds, and from aqueous solutions containing chlorine, bromine and/or iodine.
Abstract:
A rotary disc filter is provided with an integrated backwash and chemical cleaning system. In one mode of operation, backwash is directed through a control valve to one or more nozzles for spraying the backwash onto the filter media forming a part of a rotary disc filter. In a second mode, a chemical cleaning mode, the pump directs backwash through an eductor that induces a chemical into the inductor which is mixed with the backwash to form a backwash-chemical mixture that is sprayed onto the filter media. A control system is used in conjunction with the backwash and cleaning systems to monitor process information and/or filter media properties and to determine when to perform backwashes and regenerative cleanings in order to optimize the performance of the filter system.