Apparatus and method for real time and real flow-rates measurements of oil and water cuts from oil production
AssigneeSpinlock Srl
InventorDaniel Pusiol
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Abstract
A inventive flow-meter uses a measuring method which is based on the passage time of fluid molecules in a single sensor, without using any magnetic field gradient for the measurement of said fluid mean velocity. This method consists of the ultrafast irradiation of hydrogen nuclei from fluid molecules through pulses which are repeated every short time intervals, following a Carr-Purcell-Meiboom-Gill (CPMG) type sequence.
Claims20
An apparatus for the real time and real volume measuring of flow-rate and cut of the production of a complex fluid, characterized in that said apparatus comprises a magnetic resonance sensor module, a pulsed pre-polarization magnetic module of variable length and a control computer for the acquisition and transfer of data, all of which are mutually associated.
A method for the direct measurement in real time and flow-rates of the proportion and flow-rate of the different components which form a multiple-component complex fluid, which method makes use of the above device, said method comprising the following steps:
- a. activation of the first segment of the pre-polarization magnetic field in order to pre-polarize resonant nuclei of said multiple-component complex fluid during a time adequate regarding the spin-lattice relaxation time T1 of said first selected component in order to establish proportion and flow-rate thereof;
- b. transmission of radio-frequency pulses through a transmitter Tx included in said radio-frequency electronic module, according to the CPMG pulses sequence;
- c. emission of said radio-frequency pulses from said radio-frequency electronic module towards said magnetic resonance sensor module in order to excite said resonant nuclei of said complex fluid and generate a magnetic resonance signal (NMR) as a response to said emitted radio-frequency pulses;
- d. reception of response signals at said sensor assembly;
- e. emission of said signals in said sensor assembly, through said receiver Rx, included in said radio-frequency electronic module;
- f. digitalization of said response signals received by an analog/digital converter which is included in said magnetic resonance digital module;
- g. sending of said digitalized signals to said control computer;
- h. activation of said second segment of said pre-polarization magnetic field in order to pre-polarize said resonant nuclei of said multiple-component complex fluid during a time appropriate as regards the value of said second shorter spin-lattice relaxation time T1 of said selected second component for the determination of its proportion and flow-rate;
- i. repetition of steps b) to h) in order to obtain adequate signals for their further mathematical analysis in order to obtain relative proportions and flow-rates of the different components of said complex fluid;
- j. activation of said third segment of said pre-polarization magnetic field in order to pre-polarize said resonant nuclei of said multiple-component complex fluid during a time appropriate as regards the value of said third shorter spin-lattice relaxation time T1 of said selected third component for the determination of its proportion and flow-rate;
- k. repetition of steps b) to j) in order to obtain adequate signals for their further mathematical analysis in order to obtain relative proportions and flow-rates of the different components of said complex fluid;
- l. repetition of said steps until all of the measurable components are measured;
- and
- m. by means of adequate mathematical operations, processing of the obtained resonance signals in order to obtain proportion and flow-rate of each of the components of the complex fluid.
A method and respective apparatus for the spatial selection of the volume of the production duct, in order to measure in real time and flow-rates the flow-rate and cut of the production of a complex fluid, characterized in that said volume to be measured is selectively excited by means of the application of magnetic field gradients and excitation pulses of reduced bandwidths.
Dependencies are inferred from the claim text.