Abstract: Methods and apparatus for desolvating flowing liquid streams while retaining temporal resolution of dissolved substrates are disclosed. A novel small-scale self-regulating spray dryer preserves temporal resolution while desolvating a liquid chromatography eluent stream and depositing the solute onto an optical surface for infrared spectrographic analysis. The liquid eluent is pumped through a heated nebulizer to create a high-speed jet of solute containing liquid and solvent vapor. This jet is directed circumferentially inside a hot cylindrical cavity. Centrifugal force causes the larger liquid droplets to travel along the outer diameter of the cavity. The cavity surface is heated to cause the droplets to film boil. Film boiling reduces droplet contact with the cavity surface thereby retaining the solute in the droplets. The solute temperature is limited by controlling the pressure into which the solvent evaporates from the droplets.

Abstract: Some embodiments of the invention relate to an electrodeionization device that includes comprising a generally cylindrical housing. The cylindrical housing includes a cylindrical inner core and an inner electrode that extends around the inner core. The cylindrical housing includes a leaf arranged as a spiral winding about the inner electrode and an outer electrode that extends about the spiral winding. Active treatment cells are defined by spaces within the spiral winding and by interleaf spaces thereof. One or more sealing bands extend between membranes of the spiral winding to define fluid flow.

Abstract: A cross flow filtration apparatus for nanofiltration or reverse osmosis has pressure vessels with a plurality of filter cartridges in each vessel. A feed port is provided at an intermediate position on the side of the vessel, and two permeate flows or branches exit opposite ends of the vessel, and the first branch has a characteristically high “upstream” flux and quality, while the second is of lesser flux and/or quality. The system provides a high degree of moduarity, enhancing flux or yield at a reduced driving pressure or overall pressure drop. Centered or off-center port, and a stop or valve in the permeate stream may apportion flows between the two outlets. Staged systems may employ a first stage bypass to achieve a target quality with increased yield. A flow divider or adaptor permits the cartridges to fit and seal in the vessel and an installation tool or sleeve may facilitate installation or replacement of cartridges having a directional perimeter seal.

Abstract: EDI apparatus for demineralizing a liquid flow is assembled in a housing having a cylindrical shape, and includes two metal electrodes, and one or more leafs, each leaf comprising a pair of selectively ion-permeable membranes arranged parallel to each other and spaced apart by spacing elements that allow liquid to flow in the interstitial space between membranes, thus forming an arrangement of dilute and concentrate cells in a desired flow configuration. Spacing elements between membranes, as well as between leaves, can be formed of inert polymer material, ion exchange beads, ion exchange fibers, a combination of two or more these elements, or a porous media incorporating one or more of such elements as an intrinsic part. An inner or central electrode and an outer or perimeter electrode establish a generally uniform and radially-oriented electrical or ionic current between the inner and the outer electrodes, across the helical flow spaces defined by the membrane/spacer windings.

Abstract: A water treatment system and method including a membrane-based boron removal unit includes a boron analyzer for detecting the concentration of boron in a treatment stream. The boron removal unit can be a reverse osmosis (RO) or electrodeionization (EDI) treatment unit. A controller responds to the detected boron concentration to control an operation of the RO or EDI units. In an EDI system, the controller may adjust current or voltage supplied to match current to changes in ionic load and maintain a portion of the dilute cell in a substantially regenerated state. In an RO system, the controller may control the high pressure side flow rate, the brine blowdown rate, the product water permeation rate, pH, or feed rate of chemicals in response to the detected boron concentration value.

Abstract: Apparatus and method are disclosed for introducing ion exchange or other particulates into compartments of an already-assembled electrodeionization or comparable stack by modulating a flow of slurry into the compartments with slugs of gas such as air. The air propels liquid through the cells, scavenging ponded liquid so that the particulates (which are retained, e.g., by a strainer or obstruction, in compartment of the apparatus) are deposited as well-packed beds to fill the compartments. Pressurized air filling protocols may deliver discrete slugs of slurry between bursts of air, and the direction of filling may be periodically reversed to diminish particle bed non-homogeneities or settling gradients that arise during transport. The slugs of air may be applied in the direction of slurry flow, in the reverse direction, or both. Different slurries may be transported in a sequence to form layered and packed beds of enhanced utility.

Abstract: A water treatment system and method including a membrane-based boron removal unit includes a boron analyzer for detecting the concentration of boron in a treatment stream. The boron removal unit can be a reverse osmosis (RO) or electrodeionization (EDI) treatment unit. A controller responds to the detected boron concentration to control an operation of the RO or EDI units. In an EDI system, the controller may adjust current or voltage supplied to match current to changes in ionic load and maintain a portion of the dilute cell in a substantially regenerated state. In an RO system, the controller may control the high pressure side flow rate, the brine blowdown rate, the product water permeation rate, pH, or feed rate of chemicals in response to the detected boron concentration value.

Abstract: Water treatment systems or assemblies are normally tested after construction, at least for leaks, prior to shipping or storage. Pressure testing with a gas is hazardous, so testing with water is a standard method. After testing, the water is displaced from the system by draining or gas phase flushing. It is nearly impossible to remove all of the water from the system or assembly. This remaining water provides an environment for biological growth which contaminates the system or assembly over time. The purpose of this invention is to eliminate or minimize this biological contamination by adding a biocidal agent to the system or assembly before sealing it for shipment or storage.

Abstract: An improved apparatus and operating method related thereto for deionizing water to produce substantially pure water using electric field and ion exchange materials are disclosed, including embodiments incorporating one or more of the novel features of brine and electrode streams flowing in a direction counter-current to the stream being deionized, a filling of the brine stream with stratified ion exchange materials, a stream mixing feature for mixing the stream being deionized, a gas removal feature for removal of gases, a spiral-wound embodiment of an electrodialysis device according to the invention, and a method for determining the preferred operating current for electrodialysis systems according to this invention.

Abstract: An electrolytic process and apparatus are disclosed for continuously producing the cation conductivity, anion conductivity, and temperature data required for continuous monitoring of the pH of high-purity aqueous solution flows. The cation exchange material and the anion exchange material used for conditioning water samples for conductivity measurements are continuously regenerated by applying a DC electric voltage between an anode and a cathode either across the cation exchange material, whereby hydrogen ions generated at the anode move through the cation exchange material displacing cations previously absorbed and these displaced cations under the influence of the electric field migrate to the cathode, or across the anion exchange material, whereby hydroxyl ions generated at the cathode regenerate the anion exchange material.

Abstract: Apparatus and methods have been developed to deliver automatically a sample to a reaction vessel, an analytical device or any location where sample introduction or deposition is desired. A sample delivery system of the invention generally includes a housing defining a channel, e.g., a capillary, and a volume controller, which is a temperature control device, in thermal communication with the channel. The channel preferably is closed at one end, and contains an opening for introduction of a sample. The closed end of the channel is associated thermally with the temperature control device. The temperature control device heats and cools a thermally expandable fluid in the channel which controls movement of a sample into, within and out of the channel.

Abstract: Apparatus and method are disclosed for introducing ion exchange or other particulates into compartments of an already-assembled electrodeionization or comparable stack by modulating a flow of slurry into the compartments with slugs of gas such as air. The air propels liquid through the cells, scavenging ponded liquid so that the particulates (which are retained, e.g., by a strainer or obstruction, in compartment of the apparatus) are deposited as well-packed beds to fill the compartments. Pressurized air filling protocols may deliver discrete slugs of slurry between bursts of air, and the direction of filling may be periodically reversed to diminish particle bed non-homogeneities or settling gradients that arise during transport. The slugs of air may be applied in the direction of slurry flow, in the reverse direction, or both. Different slurries may be transported in a sequence to form layered and packed beds of enhanced utility.

Abstract: Water treatment systems or assemblies are normally tested after construction, at least for leaks, prior to shipping or storage. Pressure testing with a gas is hazardous, so testing with water is a standard method. After testing, the water is displaced from the system by draining or gas phase flushing. It is nearly impossible to remove all of the water from the system or assembly. This remaining water provides an environment for biological growth which contaminates the system or assembly over time. The purpose of this invention is to eliminate or minimize this biological contamination by adding a biocidal agent to the system or assembly before sealing it for shipment or storage.

Abstract: The present invention is directed to apparatus and methods for rapid, automated, microscale sample analysis using pressure differentials. The invention includes an apparatus having intersecting channels for introduction of a sample and separation of that sample into its components. The sample introduction and separation channels preferably are etched in a microfabricated device, such as a microchip, to form a junction. Pressure gradients are applied to the channels to form a sample plug in the separation channel. The separation channel may have disposed within it a medium for separation of the components suspected to be contained in the sample. For example, with the proper medium, a voltage gradient may be applied along the separation channel to separate the components of the sample electrophoretically. The apparatus also may include means for detecting the components of the sample subsequent to separation.

Abstract: An interface apparatus for introducing a sample for analysis from a liquid flow into a mass spectrometer as a plurality of charged droplets is disclosed. The interface apparatus includes interface body which defines a spray chamber and an orifice, a spray means defining a liquid-flow inlet channel and an excess-sample-flow exit channel and having an open end disposed inside the spray chamber, and a voltage device for applying a voltage to the sample to form a plurality of charged droplets. The charged droplets pass through the orifice in the interface body and are introduced into a mass spectrometer for analysis. The interface includes a valve for regulating the flow of sample into the sample inlet channel and a device for imposing a pressure gradient on the sample at the open end which induces the sample to flow from the sample inlet channel through the excess sample outlet channel.

Abstract: An apparatus to effect multiple simultaneous separations to measure absorbance, comprising a photodetector array comprising a plurality of photosensitive elements connected to provide a serial output. The elements are typically pixels of a photodiode array (PDA). The elements are illuminated by a light source positioned to illuminate at least a portion of the photodetector array. The light source may be a an AC or DC mercury lamp or other useable light source for chromatography. An array of separation channels is disposed between the light source and the photodetector array, each of the separation channels having a lumen, a sample introduction end and a detection region disposed opposite the sample introduction end. Typically and as disclosed herein the array is a multiple parallel capillary electrophoresis system.

Abstract: An improved gradient proportioning valve compensates for hydraulic inertia in a compact, reliably sealed valve assembly that is less susceptible to unswept volumes and gas permeation. A flat diaphragm is located within an accumulator volume integral to a valve manifold block. The compliance and damping of the diaphragm are optimized for the application's flow characteristics. Sealing of the diaphragm is provided by a sealing plug installed in the manifold block. The diaphragm has only one sealing joint. The sealing plug configuration allows for a more reliable clamping and sealing of the diaphragm which reduces and substantially eliminates the potential for leaks. Potential for unswept volumes is substantially eliminated by including the accumulator volume as a unitary part of the valve manifold. Air permeation into the fluid stream is substantially reduced by a reduction in surface area and exposed liquid volume in the accumulator, effected by including the accumulator volume as part of the valve manifold.

Abstract: A gear pump is used for the primary flow source for a low pressure, high performance separation system. The pump is controlled such that its flow and leakage characteristics are compensated by an electronic controller which results in controlled output flow rates to a variety of loads. The pump is particularly suited for use in liquid chromatography (LC) systems, especially LC systems which use membrane based separation media. A modification to the gear pump results in an efficient mixer, further enhancing its use in LC systems which involve gradient operational modes. Also disclosed are embodiments which allow the gear pump to be used in high pressure separation systems, e.g., high performance liquid chromatography (HPLC) systems.

Abstract: A flow cell for optically analyzing a liquid sample is coated with a fluoropolymer having a refractive index less than the refractive index of water.

Abstract: A sample is injected into a capillary tube of a capillary electrophoresis apparatus. A sample solute on a porous layer is positioned in contact with an entrance end of the capillary tube and electrodes are positioned at the entrance end and exit end of the tube. The separated sample is collected at the exit end of the tube.