CN102183675A - Polyacrylamide aqueous solution fluid ultra low flow velocity measuring method and polyacrylamide aqueous solution viscosity measuring method using same - Google Patents

Abstract

The invention relates to a polyacrylamide aqueous solution fluid ultra low flow velocity measuring method and a polyacrylamide aqueous solution viscosity measuring method using the same, belongs to the field of polymer parameter measuring technology, and solves the problem of the prior art that the polyacrylamide aqueous solution ultra low flow velocity can not be measured and the actual flow velocity and viscosity of the polyacrylamide aqueous solution fluid in an underground oil field core can not be obtained. The first scheme is carried out by the steps of connecting the lower portion of a polyacrylamide aqueous solution storage tank with an inlet of a glass capillary, connecting an outlet of the glass capillary with a solution collecting bottle, observing the solution in the glass capillary via a microscope, recording the time consumed by a microparticle when passing an observation segment of the glass capillary, and obtaining a flow velocity after calculation. Based on the first scheme, the second scheme calculates the inlet pressure drop when the polyacrylamide aqueous solution flows into the glass capillary, and finally obtains the viscosity of the polyacrylamide aqueous solution after calculation. The invention is applied to measure the ultra low flow velocity of a liquid and to further obtain the viscosity of an ultra low flow velocity liquid.

Description

The measuring method of the ultralow flow velocity of polyacrylamide solution fluid and adopt this method to measure the polyacrylamide solution method of viscosity

Technical field

The present invention relates to a kind of polyacrylamide solution fluid ultralow flow velocity measuring method and adopt this method to measure the polyacrylamide solution method of viscosity, belong to the polymkeric substance parameter measuring technical field.

Background technology

Extensively adopt tertiary oil recovery technology at present in oil exploitation technology, wherein polymer displacement of reservoir oil tech effectively raises the recovery ratio of oil.Use the oil field of polymer flooding need carry out the modeling effort of oil field numerical value, for example: the viscosity of polymkeric substance and the relation of concentration, rheological and the optimization process of design parameter etc. of polymer solution in porous medium, wherein most important parameter is the viscosity of polymer solution in porous medium.

The polymkeric substance that the oil field displacement of reservoir oil is adopted is generally polyacrylamide solution, the viscosity of polyacrylamide solution need be calculated acquisition according to flow velocity, the flowing velocity scope of polyacrylamide solution in the core of underground oil field is 1-5m/d, promptly be equivalent to 0.012-0.057mm/s, flow velocity is very low.The instrument that low flow rate of liquid is measured that uses at present is a Doppler laser velocimeter, the flow rates that it is measured only is 0.1mm/s-1000m/s, this and the actual flow velocity gap of polyacrylamide solution in the core of underground oil field are very big, obviously can't realize obtaining the viscosity of polyacrylamide solution.

Summary of the invention

The objective of the invention is to realize measurement to the ultralow flow velocity of polyacrylamide solution in order to solve prior art, and can't realize the measurement of its actual flow velocity in the core of underground oil field, and then can't obtain the problem of its viscosity, provide a kind of polyacrylamide solution fluid ultralow flow velocity measuring method and adopt this method to measure the polyacrylamide solution method of viscosity.

First kind of technical scheme of the present invention is:

The measuring method of the ultralow flow velocity of polyacrylamide solution fluid, the lower end of polyacrylamide solution being store the pond is connected with the inlet of micron-sized glass capillary by sebific duct, glass capillary is horizontal positioned, and the lower end in polyacrylamide solution storage pond is higher than the tube hub line of glass capillary; The outlet of glass capillary connects the inlet of solution receiving flask, and glass capillary and solution receiving flask are placed in the constant temperature oven;

Adopt the solution in the microscopic examination glass capillary, and selected glass capillary length is one section conduct observation section of S in the microscopical visual field, measuring process is:

Step 1: in polyacrylamide solution storage pond, inject polyacrylamide solution;

Step 2:, and, calculate the flowing velocity u that obtains described molecule then by the used time t of observation section that flows through of a molecule in the stopwatch record polyacrylamide solution by the observation section of microscopic examination glass capillary:

u＝S/t，

The flowing velocity u of molecule is the flowing velocity of polyacrylamide solution.

Second kind of technical scheme of the inventive method is:

Measure the polyacrylamide solution method of viscosity, the lower end of polyacrylamide solution being store the pond is connected with the inlet and the liquid level gauge of micron-sized glass capillary by sebific duct simultaneously, glass capillary is horizontal positioned, and the lower end in polyacrylamide solution storage pond is higher than the tube hub line of glass capillary, the lower end in the lower end of liquid level gauge and polyacrylamide solution storage pond is positioned on the same horizontal line, the outlet of glass capillary connects the inlet of solution receiving flask, and glass capillary and solution receiving flask are placed in the constant temperature oven;

Adopt the solution in the microscopic examination glass capillary, and selected glass capillary length is one section conduct observation section of S in the microscopical visual field, measuring process is:

Step 1: in polyacrylamide solution storage pond, inject polyacrylamide solution;

Step 2:, and, calculate the flowing velocity u that obtains described molecule then by the used time t of observation section that flows through of a molecule in the stopwatch record polyacrylamide solution by the observation section of microscopic examination glass capillary:

u＝S/t，

The flowing velocity u of molecule is the flowing velocity of polyacrylamide solution;

Step 3: P falls in the inlet pressure when calculating polyacrylamide solution inflow glass capillary;

Step 4: calculate the viscosity, mu that obtains polyacrylamide solution.

Advantage of the present invention is: the inventive method adopts micron-sized glass capillary as the porous medium physical model, come the core in oil field under the simulation well, use conventional physical apparatus, they are combined the measurement of the ultralow flow velocity of promptly having realized the polyacrylamide solution fluid, solved the problem that Doppler laser velocimeter can't be measured ultralow flow velocity.It is simple, and is cheap, the precision height.

The inventive method is by measuring the flow velocity of molecule in the polyacrylamide solution, calculate the viscosity that obtains polyacrylamide solution again, implementation method is simple, the scope of testing the speed that can reach is 0.01mm/s-0.1mm/s, the estimated value of precision is 0.5%, can satisfy the measurement needs of the flowing velocity of polyacrylamide solution in the core of underground oil field.

Description of drawings

Fig. 1 is the process flow diagram of embodiment two described methods;

Fig. 2 is the device synoptic diagram that embodiment two described methods adopt.

Embodiment

Embodiment one: present embodiment is described in conjunction with Fig. 2, the measuring method of the ultralow flow velocity of the polyacrylamide solution fluid described in the present embodiment, the lower end of polyacrylamide solution being store pond 1 is connected by the inlet of sebific duct with micron-sized glass capillary 2, glass capillary 2 is horizontal positioned, and the lower end in polyacrylamide solution storage pond 1 is higher than the tube hub line of glass capillary 2; The outlet of glass capillary 2 connects the inlet of solution receiving flask 3, and glass capillary 2 and solution receiving flask 3 are placed in the constant temperature oven 4;

Adopt the solution in the microscopic examination glass capillary 2, and selected glass capillary 2 length are one section conduct observation section of S in the microscopical visual field, measuring process is:

Step 1: in polyacrylamide solution storage pond 1, inject polyacrylamide solution;

Step 2:, and, calculate the flowing velocity u that obtains described molecule then by the used time t of observation section that flows through of a molecule in the stopwatch record polyacrylamide solution by the observation section of microscopic examination glass capillary 2:

u＝S/t，

The flowing velocity u of molecule is the flowing velocity of polyacrylamide solution.

Embodiment two: present embodiment is for to the further specifying of embodiment one, and a molecule in the described polyacrylamide solution is the molecule that is in the tube hub place of glass capillary 2.Other is identical with embodiment one.

The flowing velocity of the molecule at the tube hub place of glass capillary 2 is the fastest, finds easily in numerous particles.

Embodiment three: below in conjunction with Fig. 1 and Fig. 2 present embodiment is described,

The measuring method of the ultralow flow velocity of the employing embodiment one described polyacrylamide solution fluid described in the present embodiment is measured the polyacrylamide solution method of viscosity, the lower end of polyacrylamide solution being store pond 1 is connected with the inlet and the liquid level gauge 5 of micron-sized glass capillary 2 by sebific duct simultaneously, glass capillary 2 is horizontal positioned, and the lower end in polyacrylamide solution storage pond 1 is higher than the tube hub line of glass capillary 2, the lower end in the lower end of liquid level gauge 5 and polyacrylamide solution storage pond 1 is positioned on the same horizontal line, the outlet of glass capillary 2 connects the inlet of solution receiving flask 3, and glass capillary 2 and solution receiving flask 3 are placed in the constant temperature oven 4;

Adopt the solution in the microscopic examination glass capillary 2, and selected glass capillary 2 length are one section conduct observation section of S in the microscopical visual field, measuring process is:

Step 1: in polyacrylamide solution storage pond 1, inject polyacrylamide solution;

Step 2:, and, calculate the flowing velocity u that obtains described molecule then by the used time t of observation section that flows through of a molecule in the stopwatch record polyacrylamide solution by the observation section of microscopic examination glass capillary 2:

u＝S/t，

The flowing velocity u of molecule is the flowing velocity of polyacrylamide solution;

Step 3: P falls in the inlet pressure when calculating polyacrylamide solution inflow glass capillary 2;

Step 4: calculate the viscosity, mu that obtains polyacrylamide solution.

Micron-sized glass capillary 2 described in the present embodiment is used for the porous medium in simulate formation oil field, the tube hub line that the lower end in polyacrylamide solution storage pond 1 is higher than glass capillary 2 is to fall in order to produce fluid pressure, microscope can sight glass kapillary 2 in the flow state of molecule in the polyacrylamide solution.Constant temperature oven 4 makes glass capillary 2 be in temperature constant state, so that the density of solution keeps stable in the glass capillary 2.

Principle of work:

Polyacrylamide solution in the polyacrylamide solution storage pond 1 falls under the effect at the pressure that liquid level gauge 5 produces, can in glass capillary 2, flow, because the molecule in the polyacrylamide solution is along with liquid flows together, therefore and molecule can be observed by microscope, with the flowing velocity of the molecule flowing velocity as polyacrylamide solution.This method makes the acquisition of viscosity, mu become simpler, is easy to realize.

Embodiment four: present embodiment is for to the further specifying of embodiment three, and a molecule in the described polyacrylamide solution is the molecule that is in the tube hub place of glass capillary 2.Other is identical with embodiment three.

The flowing velocity of the molecule at the tube hub place of glass capillary 2 is the fastest, finds easily in numerous particles.

Embodiment five: present embodiment is for to the further specifying of embodiment three or four,

The method that P falls in the inlet pressure when calculating polyacrylamide solution inflow glass capillary 2 described in the step 3 is:

Adopt altimeter to measure to obtain the difference in height h of the tube hub line of initial liquid level in the polyacrylamide solution storage pond 1 and glass capillary 2, then the pressure of polyacrylamide solution falls P and is:

P＝ρgh，

ρ is that density, the g of polyacrylamide solution are acceleration of gravity in the formula.

Other is identical with embodiment three or four.

After the acquisition of difference in height h can be measured the height of tube hub line of the elemental height of polyacrylamide solution liquid level and glass capillary 2 respectively by liquid level gauge 5 in the present embodiment, make difference and obtain.

Embodiment six: present embodiment is for to the further specifying of embodiment five,

The method of calculating the viscosity, mu that obtains polyacrylamide solution described in the step 4 is:

At first calculate the shear rate of polyacrylamide solution

$\stackrel{\·}{\mathrm{\γ}}=4u/d,$

D is the internal diameter of glass capillary 2 in the formula;

Calculate the shear stress τ of polyacrylamide solution then:

τ＝Pd/4L，

L is the total length of glass capillary 2 in the formula;

According to shear rate

Calculate viscosity, mu with shear stress τ:

$\mathrm{\μ}=\mathrm{\τ}/\stackrel{\·}{\mathrm{\γ}}.$

Claims (6)

1. the measuring method of the ultralow flow velocity of a polyacrylamide solution fluid, it is characterized in that: the lower end of polyacrylamide solution being store pond (1) is connected by the inlet of sebific duct with micron-sized glass capillary (2), glass capillary (2) is horizontal positioned, and the lower end in polyacrylamide solution storage pond (1) is higher than the tube hub line of glass capillary (2); The outlet of glass capillary (2) connects the inlet of solution receiving flask (3), and glass capillary (2) and solution receiving flask (3) are placed in the constant temperature oven (4);

Adopt the solution in the microscopic examination glass capillary (2), and selected glass capillary (2) length is one section conduct observation section of S in the microscopical visual field, measuring process is:

Step 1: in polyacrylamide solution storage pond (1), inject polyacrylamide solution;

Step 2:, and, calculate the flowing velocity u that obtains described molecule then by the used time t of observation section that flows through of a molecule in the stopwatch record polyacrylamide solution by the observation section of microscopic examination glass capillary (2):

u＝S/t，

The flowing velocity u of molecule is the flowing velocity of polyacrylamide solution.

2. the measuring method of the ultralow flow velocity of polyacrylamide solution fluid according to claim 1 is characterized in that: a molecule in the described polyacrylamide solution is the molecule that is in the tube hub place of glass capillary (2).

3. one kind is adopted the measuring method of the ultralow flow velocity of the described polyacrylamide solution fluid of claim 1 to measure the polyacrylamide solution method of viscosity, it is characterized in that: the lower end of polyacrylamide solution being store pond (1) is connected with the inlet and the liquid level gauge (5) of micron-sized glass capillary (2) by sebific duct simultaneously, glass capillary (2) is horizontal positioned, and the lower end in polyacrylamide solution storage pond (1) is higher than the tube hub line of glass capillary (2), the lower end in the lower end of liquid level gauge (5) and polyacrylamide solution storage pond (1) is positioned on the same horizontal line, the outlet of glass capillary (2) connects the inlet of solution receiving flask (3), and glass capillary (2) and solution receiving flask (3) are placed in the constant temperature oven (4);

Adopt the solution in the microscopic examination glass capillary (2), and selected glass capillary (2) length is one section conduct observation section of S in the microscopical visual field, measuring process is:

Step 1: in polyacrylamide solution storage pond (1), inject polyacrylamide solution;

Step 2:, and, calculate the flowing velocity u that obtains described molecule then by the used time t of observation section that flows through of a molecule in the stopwatch record polyacrylamide solution by the observation section of microscopic examination glass capillary (2):

u＝S/t，

The flowing velocity u of molecule is the flowing velocity of polyacrylamide solution;

Step 3: P falls in the inlet pressure when calculating polyacrylamide solution inflow glass capillary (2);

Step 4: calculate the viscosity, mu that obtains polyacrylamide solution.

4. measurement polyacrylamide solution method of viscosity according to claim 3 is characterized in that: a molecule in the described polyacrylamide solution is the molecule that is in the tube hub place of glass capillary (2).

5. according to claim 3 or 4 described measurement polyacrylamide solution method of viscosity, it is characterized in that: the method that P falls in the inlet pressure when calculating polyacrylamide solution inflow glass capillary (2) described in the step 3 is:

The difference in height h of the initial liquid level that adopts altimeter to measure to obtain in the polyacrylamide solution storage pond (1) and the tube hub line of glass capillary (2), then the pressure of polyacrylamide solution falls P and is:

P＝ρgh，

ρ is that density, the g of polyacrylamide solution are acceleration of gravity in the formula.

6. measurement polyacrylamide solution method of viscosity according to claim 5 is characterized in that: the method for calculating the viscosity, mu that obtains polyacrylamide solution described in the step 4 is:

At first calculate the shear rate of polyacrylamide solution

$\stackrel{\·}{\mathrm{\γ}}=4u/d,$

D is the internal diameter of glass capillary (2) in the formula;

Calculate the shear stress τ of polyacrylamide solution then:

τ＝Pd/4L，

L is the total length of glass capillary (2) in the formula;

According to shear rate Calculate viscosity, mu with shear stress τ:

$\mathrm{\μ}=\mathrm{\τ}/\stackrel{\·}{\mathrm{\γ}}.$

Images