Abstract: The present invention provides a method for the removal of biofilms composed of microorganisms from submerged surfaces in an aqueous medium comprising contacting said biofilm with an aqueous stabilized chlorine dioxide and at least one nutrient source, wherein said nutrient source is provided in an amount effective to result in the generation of one or more acidic compounds by said biofilm, and the aqueous stabilized chlorine dioxide is provided in an amount sufficient, when activated by said one or more acidic compounds generated by said microorganisms, to kill a sufficient number of microorganisms in the biofilm to result in the biofilm's removal. Optionally a second biocide may be provided with or after the nutrient source to kill any microorganisms released from the biofilm during its removal and thereby inhibit the reformation of the biofilm.
Abstract: Methods for controlling the formation of proteinaceous fouling deposits in high temperature evaporators and concentrators as employed in processing steepwater in the wet milling of corn. The methods comprise adding a surfactant, preferably a nonionic surfactant to the steepwater. Particularly effective surfactants are oxyalkylated sorbitan R surfactants where R is monooleate, trioleate, monostearate, tristearate, monopalmitate and monolaurate.
Abstract: A three or optionally four stage process for the continuous removal of a gum phase from triglyceride oil is described in which in a first stage the oil containing a separate gum phase is subjected to centrifugal separation in a first centrifugal separator to yield gums with low oil content and an oil that still contains a fraction of the gums originally present in the feed, in a second stage the oil obtained from the first stage is subjected to centrifugal separation in a second centrifugal separator to yield oil with a further reduced residual gum content and a gum phase with a higher oil content than the gums obtained in the first stage, in a third stage the gum phase obtained in the second stage is recycled into the oil stream fed to the first centrifugal separator and optionally in a fourth stage the oil obtained in the second stage is washed one or more times with water.
Type:
Grant
Filed:
March 14, 1989
Date of Patent:
May 22, 1990
Assignee:
N.V. Vandemoortele International
Inventors:
Martin van Opstal, Frans Dewulf, Bernard Cleenewerck, Ernst Weber
Abstract: The present invention solves the problem of managing resin-containing waste liquors within the cellulose pulp industry. The invention relates to a method for purifying resin-containing waste liquor in the manufacture of cellulose pulp, in which method a pH-adjusting chemical is, when necessary, added to resin-containing waste liquor removed from the cellulose pulps, so that the pH of the waste liquor will lie within the pH range 1-7, and in which a water-soluble organic polymer is added to the waste liquor in the form of a forwardly moving liquid stream. The method is characterized by dividing up the requisite amount of polymer into part quantities which are introduced into the liquid stream on at least two occasions, by subjecting the liquid stream to a pronounced shearing and/or turbulent treatment process, and by subsequently separating agglomerated resin from the waste liquor.
Type:
Grant
Filed:
December 23, 1988
Date of Patent:
May 1, 1990
Assignee:
Boliden Aktiebolag
Inventors:
Cecilia M. Nordberg, Thomas B. Engstrom, Thomas Pinzke, Owe Sanneskog, Jan hlund
Abstract: An aquarium filtering apparatus having a spiral prefilter connected between a siphon input line and a return water line for removing floating debris wherein the return line cycles a portion of the return water through a "dry" biological filter for decomposing biological waste and through a chemical stage filter for eliminating undesirable chemical waste from the aquarium water, the filtering apparatus further including a concentric tube arrangement having an outer inlet tube for receiving water from the spiral prefilter and an inner inlet tube for receiving water from the chemical stage filter, the prefilter operating in paralle with the biological and chemical stage filters permitting the concentric tube arrangement to maintain a pair of water levels within the aquarium filter by utilizing a single submersible pump, the pair of water levels ensuring that the pump remains submersible and the biological filter remains non-submersible which minimizes filter recycling time and improves filter efficiency while be
Abstract: A process for clarifying and reclaiming industrial working fluids and/or outdoor working locations such as oil and gas well working fluids and pits. A treating agent is added to the fluid in an amount exceeding its solubility therein to precipitate soluble contaminants and to form a layer of treating agent over a lower layer of sludge at the pit bottom comprising insoluble contaminants and the precipitates. The layer of treating agent compresses the sludge and serves as a filter/barrier to increase the amount of overlying clarified fluid which can be collected. Following separation of the clarified fluid for disposal or reuse, the sludge is solidified by adding a further treating agent. The process is particularly suited for use in oil and gas well exploration wherein the treating agent is a particulate material including lime.
Type:
Grant
Filed:
April 26, 1989
Date of Patent:
January 23, 1990
Assignees:
George D. Smith, John J. Smith, Gregory New, Cam C. Colelli, David I. Mansberry
Abstract: The present invention provides a method and apparatus for collecting and liquefying off-gases, particularly carbon dioxide, generated by a wet oxidation of organic matter and for the on sight gasification of liquid oxygen for use as an oxidant in the wet oxidation reaction. Through a series of separation and pressurization operations, high pressure off-gases are introduced into a heat exchanger at substantially the same time as liquid oxygen. The liquid oxygen and compressed off-gases are in heat exchange relation in the heat exchanger but are isolated from one another. Heat is transferred from the compressed off-gases to the liquid oxygen whereby the off-gases are liquified and the liquid oxygen is gasified. The liquified off-gases may then be stored in appropriate storage units. The gaseous oxygen is used as the oxidant for the wet oxidation reaction.
Type:
Grant
Filed:
January 17, 1989
Date of Patent:
January 2, 1990
Inventors:
Joseph E. Zeigler, Hermann W. Peterscheck