FIELD OF INVENTION :

The present invention relates to the field of quantitative and qualitative measurement of fuel marker in petroleum utilizing methodologies of visible and near infra red (MR) spectral analyses. More particularly, the present invention relates to a method and apparatus for measuring the petroleum marker compounds optionally 10 both in off-line and on-line modes.

BACKGROUND:

There is considerable interest in designing apparatuses for instant measurement of

IS added markers, quantitatively and qualitatively, in petroleum products such as diesel and gasoline. Various methodologies have been introduced for measuring markers in hydrocarbon fluids. U.S. Pat. No. 3,783,284 disclosed an apparatus to determine the presence of petroleum products in an area containing water by applying an active infrared source. The principle of this method is based on reflected infrared radiation

20 filtered by two filters at two different wavelengths, lambda 1 and +80 {hd 2. Two

infrared detectors produce signals, proportional to the detection of the reflected radiation at the wavelengths +80 {hd 1 and +80 {hd 2. U.S. Pat. No. 0,180,556 disclosed a method of detection of markers in pressurized hydrocarbon fluids, the methodology of which is based on an inline system detecting of the marker in a

25 pressurized hydrocarbon fluid. The system is fixed in a pressurized hydrocarbon

fluid supply line such that pressurized hydrocarbon fluid flowing from one location to a second location in the supply line passes through a detection system. Dyes and markers (referred to collectively as "tags" herein) are expected to distinguish chemically or physically similar liquids. As an example, fuels were dyed to provide

30 visually distinctive brand and grade denominations for commercial and safety

reasons, In another example, some less taxed products were tagged to distinguish them from similar materials subjected to higher taxes. Furthermore, certain fuels were marked to deter fraudulent adulteration of premium grade products with lower grade products, such as by blending kerosene, stove oil or diesel fuel with regular

35 grade gasoline or blending regular grade gasoline with premium grade gasoline, The

U.S. Pat. No. 0,034,702 described a method of measuring the fluorescence of a marker compound dissolved or dispersed in a bulk material. On the other hand, a problem with the method of detecting fluorescent markers arises when the material interferes with the fluorescence of the marker by absorbing the excitation or emitted

40 light, through exhibiting its own background fluorescence, or by changing the

fluorescent characteristics of the marker, This is a particular problem in the marking of colored liquids, such as petroleum derived products, with fluorescent markers a hydrocarbon based liquids, such as fuels or diesels, exhibit a broad fluorescent emission. A further example for marker detection in fuels was disclosed in U.S. Pat. No. 5,358,873, which presented a method of detecting gasoline adulteration by tagging it with a rhodamine dye. Shaking of a small amount of the suspected fuel in a vial containing a small quantity of unbounded flash chromatography-grade silica provides detection of adulteration if the sample does not contain the marker as rhodamine marker colors the silica into red. The patents, U.S. Pat. No. 4,659,676, U.S. Pat. No. 6,991,914, U.S. Pat. No. 5,498,808 and U.S. Pat. No. 2,392,620 reported examples describing methodologies based on fluorescent signal detection.

With the patents U.S. Pat. No. 5,962,330 and U.S. Pat. No. 5,304,493 were disclosed methods, based on pretreatment of sample prior to measurement, which is a time consuming extraction process. In contrast to these patents, our present invention does not need any kind of time consuming extraction processes as the sample tests are directly preformed.

With this invention, petrol stations will be able to conduct infinite analysis using on-line optical absorbance measurements and they will be able to measure marker(s) at very low ppb concentrations. With naked eyes, it is impossible to see and distinguish the markers in liquid and gas products. They can only be distinguished by very sensitive optical methods as the markers have very low concentrations in liquid and gas products like ppb level. The use of this kind of devices is bringing big economic advantages due to use of low amount of expensive markers presented as hydrocarbons and hydrocarbon mixtures (e.g., various grades of diesel and gasoline fuels and mineral oils).

The present invention also relates to a method to labelling liquids and gases with one and more markers wherein said markers absorb optical radiation in the range of 400 - 1200 nm optical region.

Ideally, markers or chemical compounds, used in the apparatus have the following properties:

Must have complete solubility in appropriate solvent or solvent mixtures. Must keep their absorption level in the required spectral range.

- Should have detectable absorption levels when added to the liquid or gas in question at less than 1 ppm by weight.

Must keep their stability during the change of external conditions, e.g., temperature, moisture, etc, dissolved in the liquid to be marked.

Should not to be harmful to the environment, should be safe ecologically. The principle basis of marker(s) measurement can be summarized that if the marker is reliable and the liquid which is marked and qualitatively indicates the same quality as substance compounds, then apparatus is sufficiently ready to measure optical absorbance properties of the markers. Apparatus sufficiently adequate to measure marker level in the marked liquids or chemical concentration of the chemical substances and is distinguishing the unmarked liquids.

The disclosed apparatus requires only one calibration cycle and one calibration curve if the chemical content of the liquid remains stable does not change in time. If the chemical content of the liquid changes in time, a new calibration cycle is then required, after which the apparatus can read absorption level accurately.

The apparatus measurement principles of the present invention are described below.

The Figure-8 represents a model of absorbance graph when only one marker is present in the liquid. While the maximum absorption of the wavelength is Al nanometer, the apparatus reads the optical spectral range and the detector absorption amplitude as B l. The apparatus records amplitude of second absorption very close to Al nanometer, said (x) nanometer from Al nanometer away and said amplitude B2. The marker concentration is calculated by using "B1/B2" equation. Accuracy problems usually appear with non-linear calibration curves and/or overlapping peaks. In order to overcome such problems, a second derivative spectrometry methodology is applied, with which the analytical results are normalized, reflecting as positive effect on the calibration curve and overlapping peaks. When the corrected response is used instead of the uncorrected response, the considerable improvement in precision is obtained. The present invention can measure one or more markered liquids which can be analyzed using second derivative spectrometry.

Referring to the Figure-4, an example of a calibration scheme for marker concentrations between 70 and 120 ppb is illustrated. An apparatus calibration scheme is explained according to the following procedure:

Liquid samples marked at 70, 80, 90, 100, 110 and 120 ppb are prepared and measured.

Calibration equation and calibration curve are formed according to the defined marker concentrations of 70, 80, 90, 100, 110 and 120 ppb.

- New calibration coefficients are applied in the polynomial terms of x 3 , x 2 , x 1 and x°.

Considering the above described definitions, if the verification measurements limits are within the range of ±3%, the calibration process is accepted to be done properly. Ideally, the apparatus should have the minimum properties that the absorption bands of two or more markers should not overlap. The light source used in the present invention is compatible with white led, having radiation between 450-800 nanometer spectra, halogen lamb, having radiation between 360-2400 nanometer spectra and deuterium lamb, having radiation between 200-400 nanometer spectra. The computer controller of the present invention enables maintenance of a running markered liquid for each pump in each gas station. The controller of our apparatus then can compare simultaneously the marker concentrations of the running measurements and the existing deviations. This property enables the apparatus to give a message to stop the pumps. The authorized user then can choose the stop option to stop the working pumps.

The controller software of the invention has a specification to make comparison of each newly collected samples with the marker concentrations obtained from the previous runs. Another specification of the controller software herein is to stop the pumps, if the optical absorbance values of the marked liquid are out of the user defined ranges.

Referring the configuration in Figure 3, this is preferably used for on-line measurements. Referring the specially designed configuration in Figures-5 and -6, those measurement chambers are suited for pressurized applications, and it is also used for static measurements.

SUMMARY of the INVENTION:

Embodiments of the present invention relate to a method and apparatus for determination of marker(s) in petroleum products. According to the invention, a miniaturized and portable apparatus, designed to be mounted and used directly in the gas stations and by providers of petroleum products, is disclosed.

In accordance with the invention, a system possessing ultra violet (UV), visible and near infra red (NIR) spectral analyses the marker(s) concentrations in liquid and gas petroleum products is provided. Moreover, the system can also be used for determining the chemical, physical and performance properties of the analyzed hydrocarbons. Our system can measure concentrations of different markers of all kind of petroleum products, including diesel, gasoline and biodiesel. The present invention can be applied as parameters of hydrocarbons like marker concentrations in, for example, fuel refineries, fuel pipelines and fuel tankers at the defined pressure and temperature levels. It is frequently necessary to mark in order to inspect chemical levels and origins of liquids, gases and hydrocarbons. This makes it possible, for example, to differentiate agricultural diesel oil from highly taxed diesel oil or tag fuel product streams in large industrial plants, such as petroleum refinery to trace their origin.

Ultra violet (UV), visible and near infra red (NIR) optical spectral ranges may all be used for detecting pre-loaded chemical, physical and performance parameters of various marked liquid and gas materials, including hydrocarbons. Employment of optical spectrometer system along with marker(s) in the present invention, analytical chemical behaviors of liquids and gases are detected accurately. The first feature of the presented invention is the use of the apparatus in a traditional way, "off-line" analysis, i.e. static analysis of material without any flow. Static measurements have serious disadvantage as they require extensive time for sampling of material, transferring of the sample, cleaning of cuvette, analysis and reporting the results. In this long duration time, analysis conditions and chemical structure of the compound can change significantly.

The second feature the present invention is the use of the apparatus for "on-line" analysis, i.e. dynamic analysis conditions. The presented invention functions well to cover common requirements of on-line measurements. It is situated adjacent to the process line, designed to measure liquid and gas substances by dynamic optical spectral response and connected to a computer(s) for real time measurements. As an example, when it is used in a fuel pump at a petrol station, it is situated adjacent to the fuel pump. The electronic and software parts of the system can allow calibration of the marker level to be done remotely.

BRIEF DESCRIPTION OF the DRAWINGS: Figure 1-a: Perspective view of the apparatus without by-pass line and with hose

Figure 1-b: Perspective view of the apparatus without by-pass line and with screwed flange

Figure 2-a: Side view of a dispenser Figure 2-b: Front view of a dispenser Figure 3: Isometric view of the apparatus without by-pass line Figure 4: Calibration curve of marker concentrations Figure 5: Perspective view of the apparatus with by-pass line Figure 6: Isometric view of the apparatus with by-pass line Figure 7: General system design of controllers for gas stations Figure 8: Absorbance spectral diagram;

DETAILED DESCRIPTION:

The structure and function of exemplary parts of the present invention can be understood by referring to the drawings. The same reference numbers may appear in multiple figures. The reference numbers refer to the same or corresponding structure in those figures.

Figure 1-a and Figure 1-b are directed to the perspective view of the apparatus which is used for both on-line and off-line marker concentration measurements, mounted directly to a dispenser pump of a fuel station. The part (200) represents a rectangular box for an optical spectrometer and an electronic control unit, which is located on the left side of Figure 1-a and Figure 1-b. Part 100, depicted in Figure 1-a, is the cylindrical measurement chamber for the apparatus with hose. Part 400, depicted in Figure 1-b, is the cylindrical measurement chamber for apparatus with screwed flange. Referring the system configuration in Figure-2-a, where the pump hose (302) of the dispenser attached at the top of the pump is dispenser (300), the measurement apparatus (301) is located also at the top of pump dispenser, coupled directly in serial with the pump hose. The part (303) represents the pistol of the pump dispenser.

Referring the system configuration in Figure-2-b, where the pump hose (302) of the dispenser attached in lateral to the pump is dispenser (300), the measurement apparatus (301) is coupled directly in serial with the pump hose.

The present invention represents direct connection to the pump of fuel station as shown in Figures-2-a and 2-b. In industrial application, the apparatus, represented as part (301), is connected to the fuel line of the pump dispenser by ¾ or 1 finger (cloth) adapters (304). The other end of the apparatus (301) is connected to the fuel pump line or hose via ¾ or 1 finger (cloth) adapters. The apparatus can be connected to the pump with an adaptor at the top as shown in Figure-2-a or it can be connected to the pump with an adaptor, as shown in Figure-2-b, at left or right sides of the dispenser pistol. An isometric view of the apparatus without by-pass line is represented, referring to the system configuration in Figure-3. It is an optical spectrometer and an electronic control unit of the apparatus is formed as a rectangular box (200). Rectangular box can be made of plastic or metal materials, such as aluminum, stainless steel, bronze, brass, PTFE etc. The top layer (202) is connected to a rectangular box by using screws (201) through screw holes (102). Then, rectangular box is assembled with cylindrical measurement chamber by connecting the (in) circle (101) using screws (201) and screw holes (102).

The positions of the optical detector and lenses in the spectrophotometer are adjusted to have parallel and unscattered optical light. Adjustment process of the optical detector and lenses is crucial in order to obtain the maximum light beam yield onto active detection area which is emitted from a light source (108). Amplitude of the measured optical signal of the apparatus is changed with 2 nanometers step increment over the interested optical spectral range. The total scanning time of the apparatus is order of a few tens of milliseconds.

A measurement chamber (109) is constructed in cylindrical form, which is ideally eligible for applications whereas are utilized liquid and gas materials as shown in Figure-3. Due to the flexible design of the present invented apparatus, different geometrical chamber forms can be utilized. An isometric view of the apparatus is shown in Figure-3. Left side of the measurement chamber is connected to the spectrophotometer and electronic control unit (200). Right side of the measurement chamber is connected to a light source (108), which is shown in Figure-3. The measurement chamber is made of stainless steel. Instead of stainless steel, other metal types can be selected for the construction of the measurement chamber. Only important thing for this selection is that the selected material should not react with the chemical substances, e.g. raw chemicals of marker substances, already manufactured marker products and chemicals used for the applications.

In order to keep liquids and gases in the measurement chamber, the present apparatus was sealed. This was achieved by employing glass (106), o-ring (105), between stainless steel part (107) and the part (101) by using screws (201) and through holes (102). Additional o-rings (104) are placed in the channels of the parts (101), and additional flanges with bracelets (the bracelets are not shown) are used to fix both ends of the part (109). In the industrial and commercial applications, pressurized liquids and gasses are widely used. In the presence of high pressure, the bracelets are not used in the present apparatus. Instead, screwed type flanges are employed. Input and output entries of liquids and gases are connected to bottom and top flanges of the part (109).

The Figure-4 represents a calibration curve of a marker concentration (y-axis) versus measurement output of absorbance (x-axis). A perspective view of the apparatus with by-pass line is represented, referring the system configuration in Figure-5. The isometric view of the apparatus with by-pass line is represented, referring the system configuration in Figure-6.

Referring the system configuration in Figure-6, the by-pass line (400) is a screwed flange type. The by-pass line and measured chamber connections are made by smaller pipe line (407). Flow of liquid and gases are controlled and regulated by solenoid valves (408). The light source (108) produces optical spectral radiation within a range of between 200 - 1800 nanometers. The optical spectrometer and electronic control unit (406) measure the absorbance of the marker(s). This type of use of the present apparatus is suitable for applications, whereas is present high pressure and that allows static and dynamic measurements. In the case of dynamic measurements, the solenoid valves are kept in open position. The present apparatus enables controlling the solenoid valves and hence different flow rates (flow speeds), and pressure limits can be regulated. Referring the system configuration in Figure-6, the light source (108) is connected to stainless steel part (401). In order to keep liquids and gases in the measurement chamber, the present apparatus is sealed. This was achieved by employing glass (403), Teflon(s) (402) and (404), between part (401) and ends of the part (405) by using screws.

Figure-7 represents the workflow and general scope of the system design, which is applied at the same time into multiple sites of (n) number of gas stations in order to measure the marker concentrations. The working principle is based on an electronic and software system in each apparatus, which reads the optical absorption data for each pump. Every pump data of each gas station is collected by a computer. Afterwards, all the data obtained from whole gas stations are collected and stored at central database server. In the case of any disconnection between central database and PC (personal computer) of the gas station, the data coming from the device is stored on the PC. If the internet connection is active the data is sent to the central database server. The communication between gas stations and central database server is achieved through internet as encrypted or clear text (unencrypted).