Abstract: The present disclosure relates to a method for preparing an oil-in-water mixture having a predeterminable oil concentration which can be used as a reference mixture in the determination of oil concentrations of oil-in-water mixtures, comprising the steps of arranging at least one oil storage element in a container, feeding a predeterminable amount of a water-containing fluid into the container; and introducing ultrasonic waves into the fluid that are emitted in the direction of the oil storage element covered by the fluid, wherein the oil received in the oil storage element is released from the oil storage element by means of ultrasonic waves acting on the oil storage element and is distributed in the fluid. The present disclosure further relates to an apparatus for preparing an oil-in-water mixture.

Abstract: An analytical device for automated determining of a measured variable of a liquid sample comprises: a liquid storage, which includes one or more liquid containers for one or more liquids; a measuring cell for accommodating the liquid sample, especially a liquid sample, to which has been added one or more liquids from the liquid storage, and a measuring arrangement for providing one or more measurement signals correlated with the measured variable; an electronics unit, which includes a control unit for control of the analytical device and for determining the measured variable based on the measurement signals provided by the measuring arrangement; and a handling unit including a supply- and dosing, or metering, system for supplying and metering the liquid sample and liquids from the liquid storage into the measuring cell, wherein the analytical device includes at least one exchangeable cassette, into which are integrated at least parts of the liquid storage and/or at least parts of the handling unit.

Abstract: An apparatus for determining the content of at least one oxidizable constituent of an aqueous, liquid sample, comprising a high temperature reactor for decomposing the liquid sample and forming a gaseous mixture, which contains at least the constituent as a gaseous oxide, wherein the high temperature reactor has a liquid inlet for delivery of the liquid sample and a gas inlet for delivery of a carrier gas, and is connected via a gas discharge with an analysis chamber, wherein a condensing unit is placed in front of the analysis chamber for condensing water from the gas mixture, wherein, during operation of the apparatus, a gas stream of the carrier gas with the gas mixture of the high temperature reactor passes via the gas discharge and the condensing unit into the analysis chamber, and wherein, between the gas discharge and the condensing unit, a heatable filter unit is interposed for removal of salts and/or metal oxides from the gas mixture, and the gas discharge, the filter unit and optionally connecting e

Abstract: An analytical device, including: a processing system for treating a liquid sample and for supplying the treated liquid sample to a measuring cell, to the liquid sample; a measuring transducer for registering a measured value of the treated liquid sample variable; a control unit to control the processing system; and an evaluating unit for determining the measured variable based on the measured value registered by the measuring transducer. The analytical device includes at least one first supply container containing a first reagent component, at least one second supply container containing a second reagent component and a mixing apparatus, for mixing a predetermined amount of the first reagent component contained in the first supply container with a predetermined amount of the second reagent component to form a predetermined amount of the reagent.

Abstract: An analytical device for automated determining of a measured variable of a liquid sample, includes: a base module; a replaceable cassette connectable with the base module and having at least one liquid container connectable via a fluid line with a measuring cell and containing a reagent to be added to the liquid sample for forming a measured liquid; and a measuring transducer for registering measured values correlated with the measured variable for the measured liquid accommodated in the measuring cell. The cassette has, associated with the at least one liquid container, a fluid coupling apparatus having a primary component and a secondary component and serving for producing a connection of the fluid line with the liquid container.

Abstract: A method for determining the number of drops metered with a drop frequency into a reactor, especially in a high temperature decomposition system for analyzers, wherein a gas stream is flowing through the reactor. There exists in the reactor a temperature, which is greater than the boiling temperature of the liquid, and a drop metered into the reactor transforms at least partially into the gas phase following entry into the reactor, especially due to heat transfer from contact with a surface within the reactor, especially directly after contact with the surface within the reactor. With a sampling rate, which is greater than the drop frequency, a sequence of pressure signals dependent on pressure within the reactor is registered, and, from the sequence of pressure signals or from values derived therefrom, the number of drops metered into the reactor is ascertained.

Abstract: A method for removing chloride from samples containing volatile organic carbon, wherein a chloride containing sample is mixed with a difficulty volatile acid, wherein hydrochloric acid gas arises, which is present in dissolved form in a sample-acid mixture and then the hydrochloric acid gas is purged by a carrier gas from the sample-acid mixture, wherein the hydrochloric acid gas is removed from the carrier gas following the purging and the carrier gas is fed back to the sample-acid mixture. In order during the hydrochloric acid purging largely to suppress the driving out of easily volatile organic compounds, the sample-acid mixture has a temperature of approximately 3° C. to 30° C., wherein, following the purging from the sample-acid mixture, the hydrochloric acid gas is removed from the carrier gas by absorption with water.

Abstract: For an automated determination of a ammonia nitrogen content in a liquid sample, an analyzer and method are provided. The following steps are performed by the method: generating a reagent solution by electrolysis that contains hypochlorite ions to be added to the liquid sample, and feeding the reagent solution into the liquid sample; feeding at least one other reagent solution into the liquid sample and generating a reaction mixture from the reagent solutions and the liquid sample; sensing a measuring signal with a photometric measuring device that correlates with a measuring variable of the reaction mixture; and on the basis of the measuring signal, determining a measuring value for the ammonia nitrogen content with an electronic control device.

Abstract: The invention relates to a method for calibrating and/or adjusting an analytical device for chemical substances. A predetermined concentration of a chemical substance in a reference liquid is measured by mixing the reference liquid with a reagent for producing a color change, followed by irradiating with light of a predetermined wavelength. Based on the absorption of the light by the reference liquid, a concentration is determined, which is compared with the predetermined concentration of the reference liquid. In the case of which a calibrating and/or adjusting associated with the measurement process is possible without long interruptions of the measurement process, the predetermined concentration of the reference liquid is gained by mixing at least two standard, which contain different concentrations of the chemical substance.

Abstract: An analytical device for automated determining of a measured variable of a measured liquid, including: a measuring cell; a measuring transducer; a control unit; a system of liquid lines; a first liquid container which is connected to the measuring cell via a first liquid path; a second liquid container, which is connected to the measuring cell via a second liquid path, liquid path can be blocked by means of at least a second valve; wherein a first pump is associated with the first liquid container; and wherein a second pump (different from the first pump) for transport of liquid along the second liquid path is associated with the second liquid container; and wherein the analytical device has a central valve switching mechanism, especially controllable by the control unit, for actuating the first valve and the second valve.

Abstract: An analyzer automatically determines the measurement variable for a liquid sample selected from a plurality of measurement parameters. An electronic control is configured to control the analyzer based on a selection signal representing the measurement variable selected from the plurality of measurement parameters, in particular, the conveying and metering devices and the photometric measurement device. The controller controls the analyzer in order to determine the selected measurement variable, and/or, based on the selection signal, the control unit is configured to determine a measurement value for the selected measurement variable by using the measurement signal provided by the photometric measuring device.

Abstract: A method for operating an analytical apparatus for determining concentration of an analyte, especially an oxidizable substance, in a sample liquid, comprises the steps of: placing the analytical apparatus in maintenance operation; operating a metering system, which includes a pump, especially a peristaltic pump, and a supply line, for metering single volume units of a sample liquid from a source via the supply line into a reactor, wherein there exists in the reactor a temperature, which is greater than the boiling temperature of the sample liquid, so that a volume unit of the sample liquid metered into the reactor transforms at least partially into the gas phase following entry into the reactor, especially due to heat transfer from contact with a surface within the reactor, especially directly after contact with the surface within the reactor, and wherein a carrier gas is flowing through the reactor; registering at least one measuring transducer signal for detection of the transforming of the volume unit of t

Abstract: A method for removing chloride from samples containing volatile organic carbon, wherein a chloride containing sample is mixed with a difficultly volatile acid, wherein hydrochloric acid gas arises, which is present in dissolved form in a sample-acid mixture and then the hydrochloric acid gas is purged by a carrier gas from the sample-acid mixture, wherein the hydrochloric acid gas is removed from the carrier gas following the purging and the carrier gas is fed back to the sample-acid mixture. In order during the hydrochloric acid purging largely to suppress the driving out of easily volatile organic compounds, the sample-acid mixture has a temperature of approximately 3° C. to 30° C., wherein, following the purging from the sample-acid mixture, the hydrochloric acid gas is removed from the carrier gas by absorption with water.

Abstract: A method for monitoring the concentration of water borne substances in an aqueous medium, by introducing a defined amount of the aqueous medium into a gas circulatory system of an analytical apparatus which extends through a high temperature reaction chamber and a measuring chamber. The introducing of the aqueous medium occurs upstream of the high temperature reaction chamber or into it. The aqueous medium is evaporated in the high temperature reaction chamber, the water borne substance with at least one reaction partner in the high temperature reaction chamber reacts to a gaseous reaction product, and a current value of a measured variable is registered, which is a function of the concentration of the chemical species of the reaction product in the gas circulatory system.

Abstract: A method for removing chloride from samples containing volatile organic carbon, wherein a chloride containing sample is mixed with a difficultly volatile acid, wherein hydrochloric acid gas arises, which is present in dissolved form in a sample-acid mixture and then the hydrochloric acid gas is purged by a carrier gas from the sample-acid mixture, wherein the hydrochloric acid gas is removed from the carrier gas following the purging and the carrier gas is fed back to the sample-acid mixture. In order during the hydrochloric acid purging largely to suppress the driving out of easily volatile organic compounds, the sample-acid mixture has a temperature of approximately 3° C. to 30° C., wherein, following the purging from the sample-acid mixture, the hydrochloric acid gas is removed from the carrier gas by absorption with water.

Abstract: The invention relates to a method for calibrating and/or adjusting an analytical device for chemical substances. A predetermined concentration of a chemical substance in a reference liquid is measured by mixing the reference liquid with a reagent for producing a color change, followed by irradiating with light of a predetermined wavelength. Based on the absorption of the light by the reference liquid, a concentration is determined, which is compared with the predetermined concentration of the reference liquid. In the case of which a calibrating and/or adjusting associated with the measurement process is possible without long interruptions of the measurement process, the predetermined concentration of the reference liquid is gained by mixing at least two standard, which contain different concentrations of the chemical substance.

Abstract: An analytical device for automated determining of a measured variable of a measured liquid, including: a measuring cell; a measuring transducer; a control unit; a system of liquid lines; a first liquid container which is connected to the measuring cell via a first liquid path; a second liquid container, which is connected to the measuring cell via a second liquid path, liquid path can be blocked by means of at least a second valve; wherein a first pump is associated with the first liquid container; and wherein a second pump (different from the first pump) for transport of liquid along the second liquid path is associated with the second liquid container; and wherein the analytical device has a central valve switching mechanism, especially controllable by the control unit, for actuating the first valve and the second valve.

Abstract: An analytical device, including: a processing system for treating a liquid sample and for supplying the treated liquid sample to a measuring cell, to the liquid sample; a measuring transducer for registering a measured value of the treated liquid sample variable; a control unit to control the processing system; and an evaluating unit for determining the measured variable based on the measured value registered by the measuring transducer. The analytical device includes at least one first supply container containing a first reagent component, at least one second supply container containing a second reagent component and a mixing apparatus, for mixing a predetermined amount of the first reagent component contained in the first supply container with a predetermined amount of the second reagent component to form a predetermined amount of the reagent.

Abstract: A method and apparatus for automated determining of the chemical oxygen demand of a liquid sample, comprising steps as follows: mixing the liquid sample with sulfuric acid; introducing a carrier gas, especially air, into the liquid sample-sulfuric acid mixture; adding an oxidizing agent to the liquid sample-sulfuric acid mixture to form a reaction mixture; heating (especially under reflux conditions) the reaction mixture at the boiling temperature of the reaction mixture for a predetermined time period; photometrically determining consumption of an oxidizing agent in the reaction mixture; and ascertaining therefrom the chemical oxygen demand of the liquid sample, wherein all steps are automatedly performed in an analytical system with the assistance of an evaluating and control unit.

Abstract: An analytical device for automated determining of a measured variable of a liquid sample comprises: a liquid storage, which includes one or more liquid containers for one or more liquids; a measuring cell for accommodating the liquid sample, especially a liquid sample, to which has been added one or more liquids from the liquid storage, and a measuring arrangement for providing one or more measurement signals correlated with the measured variable; an electronics unit, which includes a control unit for control of the analytical device and for determining the measured variable based on the measurement signals provided by the measuring arrangement; and a handling unit including a supply- and dosing, or metering, system for supplying and metering the liquid sample and liquids from the liquid storage into the measuring cell, wherein the analytical device includes at least one exchangeable cassette, into which are integrated at least parts of the liquid storage and/or at least parts of the handling unit.