Method and Device for Measuring Hydrocarbons in Aqueous Solutions
First Claim
1. A portable fluid sampling device for the measurement of hydrocarbons in aqueous solutions comprised of:
- a bulk sample container having an open end for receiving a sample to be analyzed,a flow controller having a first end for connecting to the open end of the bulk sample container, a vent conduit projecting into the bulk sample container for transport of air, an axial fluid conduit for transferring the liquid contents of the bulk sample container to the second end of the flow controller, and a return drain chamber adjacent to the second end for receiving the analyzed solution and discharging the aqueous solution to an external source, anda cuvette adapter attached to the second end of the flow controller to receive the aqueous solution exiting the axial fluid conduit having first end with a sealed connection to the flow controller and a transparent second end for presentation of the aqueous solution to a spectrophotometric analyzer.
0 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates to a method and device for conducting the analysis of hydrocarbons in aqueous solutions, accurately matching the EPA Test Method 1664 HEM, without the need for a solvent extraction step. The solvent extraction step is eliminated by: 1) delivering the aqueous solution directly to a standard cuvette in a controlled and convenient manner, and 2) correlating the analyzer'"'"'s output reading to a predetermined calibration curve. The predetermined calibration curve is generated by having a duplicate sample of aqueous solution tested by Method 1664 and the present device and the two values correlated. The sample delivery system is comprised of a standard 1-liter sample bottle, a flow control section, and an analyzer adapting section. The sample bottle contains the aqueous solution to be analyzed. The flow control section has various conduits which allow the user to regulate the rate at which the sample flows through to the analyzer using gravity and contains an optional fill line which can be connected directly to the process that generates the aqueous media being tested. The analyzer adapting section connects the flow control section to a standard round glass cuvette and provides a sealing means. A method for using the device is presented which calls for taking multiple analyzer readings at timed intervals as the aqueous solution flows through the cuvette. The values are then averaged and compared to the Method 1664 calibration data. Accuracy of this method to the Method 1664 can be maintained with periodic recalibration, typically monthly.
23 Citations
14 Claims
-
1. A portable fluid sampling device for the measurement of hydrocarbons in aqueous solutions comprised of:
-
a bulk sample container having an open end for receiving a sample to be analyzed, a flow controller having a first end for connecting to the open end of the bulk sample container, a vent conduit projecting into the bulk sample container for transport of air, an axial fluid conduit for transferring the liquid contents of the bulk sample container to the second end of the flow controller, and a return drain chamber adjacent to the second end for receiving the analyzed solution and discharging the aqueous solution to an external source, and a cuvette adapter attached to the second end of the flow controller to receive the aqueous solution exiting the axial fluid conduit having first end with a sealed connection to the flow controller and a transparent second end for presentation of the aqueous solution to a spectrophotometric analyzer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 11)
-
-
10. A method of duplicating the results of a solvent extraction-based test method for analyzing the concentration of dilute hydrocarbons in an aqueous solution using a spectrophotometric analyzer without the use of a solvent comprising the steps of:
-
a) Pre-calibrating the spectrophotometric analyzer to the solvent-based test method to be correlated, b) Flowing a controlled continuous rate of the aqueous solution to be analyzed through the spectrophotometric analyzer, c) Over a fixed period of time, record the spectrophotometric analyzer'"'"'s readings at repeated intervals, and d) Discard the highest and lowest readings recorded and calculate the numeric average of the remaining values recorded. - View Dependent Claims (12, 13)
-
-
14. A method of determining the stratification of hydrocarbons within a container of aqueous solution using a spectrophotometric analyzer comprising the steps of:
-
a) Extracting a sample of the aqueous solution with a volume of an immiscible hydrocarbon-soluble solvent, b) Transferring a portion of the extracted aqueous solution to the analyzer and programming the absorbance reading as the analyzer “
blank.”c) Collecting a sample of the aqueous solution containing the hydrocarbons to be analyzed into a container. d) Allowing the sample to rest for a period of time that is at least as long as the residence time of the process container being analyzed. e) Flowing a controlled continuous rate of the aqueous solution to be analyzed through the spectrophotometric analyzer, f) Over a fixed period of time, recording the spectrophotometric analyzer'"'"'s absorbance readings at consistent intervals, and g) Plotting the absorbance readings measured versus time to generate a display of the varying levels of hydrocarbon content within the depth of the aqueous solution sampled.
-
Specification