RU2565181C2 - Device for mixing of different oil grades - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry, namely to devices for mixing of different oil grades. The device includes at least one oil quality measuring unit, at least one charging pump, at least one pressure control and a flow rate related to it, a device having a possibility of being connected to at least two inlet pipelines for supply of oil of different grades: from the main line and from a tank farm and at least to one outlet main pipeline of mixed oil, which contains the main line pump, the device includes at least one auxiliary pump installed on the supply pipeline of oil supplied from the tank farm, with that, the auxiliary pump supplies oil to the charging pump inlet at provision of constant flow rate via the main oil line, with that, as an auxiliary pump there chosen is a pump of a centrifugal type, which is provided with a variable frequency drive and ensures a reduced head in comparison to the charging pump.

EFFECT: improving operating reliability of the device due to reduction of head on a pressure control, which is installed after the auxiliary pump at reduction of electrical power costs.

3 cl, 2 dwg

Description

FIELD OF THE INVENTION

The invention relates to the oil industry, and more particularly to devices for mixing different types of oil, including at least one unit for measuring oil quality, at least one booster pump, at least one pressure regulator and associated flow rate, adapted for connection at least two inlet pipelines of oil supply of different grades: going from the main line and from the tank farm and at least one outgoing main pipeline of mixed oil containing magis a trawl pump, and can be effectively used as a device for mixing oil of different grades with different physicochemical properties (viscosity, density, sulfur content, pour point, etc.) to obtain a mixture with desired properties for its further transportation through the system trunk pipelines.

State of the art

A device for mixing oil is known, including at least one unit for measuring quality, at least one pump, at least one pressure regulator, adapted for connection to at least two incoming pipelines for the supply of oils of different compositions: coming from the highway and from the tank farm, and to at least one outgoing main pipeline of mixed oil (see the description for the MOD-GILB-002 model gas mixing station, manufactured by Moldon System Ltd, http://www.modcon.ru/Modcon/ Templates / showpage.asp? DBID = 1 & LNGID = 3 & TMID = 84 & FID = 426 & PID = 505).

The disadvantages of this device are the low reliability of the device due to the fact that it is characterized by large pressure drops on the regulators, and, accordingly, the operation of such a device requires high energy costs. This device requires the use of booster pumps for both types of oil with individual pressure characteristics for work in each direction. An additional disadvantage of this device is the low efficiency of the device when applying to multiple trunk pipelines simultaneously. Changing the position of one regulator upsets the balance and leads to a change in the mixture in another regulator.

It is also known from the prior art a device for mixing different grades of oil, comprising at least one unit for measuring oil quality, at least one booster pump, at least one pressure regulator and associated flow rate, a device made with the possibility of connecting it to at least two incoming pipelines for the supply of oil of different grades: coming from the main and from the tank farm and at least one outgoing main pipeline of mixed oil containing the main asos (see the description of the patent for utility model No. 12618, published in 2000).

This device is the closest in technical essence and the achieved technical result and is selected as a prototype of the invention.

The disadvantages of this device are also the low reliability of the device due to the fact that it is characterized by large pressure drops on the regulators, and, accordingly, the operation of such a device requires high energy costs. This device requires the use of booster pumps for both types of oil with individual pressure characteristics for work in each direction. An additional disadvantage of this device is the low efficiency of the device when applying to multiple trunk pipelines simultaneously. Changing the position of one regulator upsets the balance and leads to a change in the mixture in another regulator.

Disclosure of invention

Based on this original observation, the present invention mainly aims to propose an oil mixing device that can at least smooth out one of the above disadvantages, namely, to increase the reliability of the device by reducing the pressure on the pressure regulator installed after the auxiliary pump while reducing energy costs, which is the technical task.

To achieve this goal, the device for mixing different types of oil additionally contains at least one auxiliary pump installed on the oil supply pipe coming from the tank farm, and the auxiliary pump supplies oil to the inlet of the booster pump while maintaining a constant flow rate through the main oil pipeline. A centrifugal type pump equipped with a variable frequency drive and providing a lower pressure compared to a booster pump is selected as an auxiliary pump.

Thanks to these advantageous characteristics, it becomes possible to increase the reliability of the device by reducing the pressure on the pressure regulator installed after the auxiliary pump while reducing energy costs. Indeed, the auxiliary pump provides a reduced pressure, which leads to a lower pressure drop across the booster pump. In addition, it becomes possible when mixing different grades of oil in several highways to eliminate a serious drawback, namely the effect of changing the position of one pressure regulator on other pressure regulators in the device. That is, now, if it is necessary to change the composition of the oil mixture, and therefore, when changing the pressure regulator in one line, it is not necessary to align the positions of other regulators in order to maintain the calculated position in their lines. This is due to the presence of a variable frequency drive.

Another important and non-obvious consequence of the introduction of the proposed innovation is the ability to pre-calculate the position of the pressure regulator for each outgoing line, depending on the required parameters of the oil mixture at the outlet.

There is a variant of the invention in which a pump is selected as an auxiliary pump, designed for a total oil supply in the range from 0 to 50% of the supply of the entire device.

Due to this advantageous characteristic, it becomes possible to limit the mixing of different grades of oil so that an oil intake from the tank farm does not exceed the intake of oil from the main line. Indeed, the regulation of oil supply is carried out precisely on the auxiliary stream going from the tank farm. Accordingly, its contribution as a smaller component to the total flow does not exceed half, therefore, the regulation of the additional flow is limited to 50% of the total flow.

There is an embodiment of the invention in which the device for mixing different types of oil further comprises a control unit, the output of which is connected to the input of the variable frequency drive of the auxiliary pump, and the input of the control unit is connected to oil quality measuring units, while the control unit is adapted to calculate the necessary amount of pumping.

Thanks to this advantageous feature, it becomes possible to automate the process of controlling all nodes of the device and remote control all operating modes.

The set of essential features of the invention is unknown from the prior art for devices of similar purpose, which allows us to conclude that the criterion of "novelty" for the invention.

Brief Description of the Drawings

Other features and advantages of the invention clearly follow from the description below for illustration and not being restrictive, with reference to the accompanying drawings, in which:

- figure 1 schematically depicts a functional diagram of a device for mixing different grades of oil according to the invention;

- figure 2 schematically depicts the stages of the device for mixing different types of oil according to the invention.

Figure 1 is an example of the mixing of oil of two varieties, the first of which is supplied from the main line 1 connected to the main tank farm 2, and the second from the tank farm 3.

The output of the device is fed into three lines - 11, 12 and 13.

The device 4 for mixing different types of oil consists of a group of auxiliary pumps 5 of a centrifugal type, equipped with variable frequency drives and connected to the input of a group of booster pumps 6, which includes booster pumps 61, 62 and 63, one for each outgoing line 11, 12 and 13.

Auxiliary pumps 5 are designed for a total supply in the range from 0 to 50% of the supply of the entire device, that is, the maximum pressure equal to the pressure of the oil coming from the main tank farm 2 and line 1.

The booster pumps 61, 62 and 63 of the main main pumps 71, 72 and 73 are designed to supply up to 100% of the supply of the entire device and a pressure that ensures cavitation-free operation of the main pumps 71, 72 and 73.

To ensure mixing of oil in the required proportions, the group of auxiliary pumps 5 is equipped with a variable frequency drive (VFD) and pressure regulators 8 at the outlet.

If necessary, mix two grades of oil in certain proportions to determine the required volumes, ultrasonic flow meters 9 are provided at the output of the auxiliary pumps 5 and at the output of the group of booster pumps 6.

If necessary, perform the mixing of oil in the stream according to any given property (viscosity, density, sulfur content, etc.), oil quality control units (BIC) are installed on the outlet pipelines of each pump group, incorporating in-line quality analyzers, designated together as 101, 102, 103, 104, 105.

The device 4 for mixing different types of oil additionally contains a control unit, the output of which is connected to the input of a variable frequency drive of the auxiliary pumps 5, and the input of the control unit is connected to the oil quality measuring unit 10. In addition, the output of the control unit is connected to pressure regulators 8. Electrical circuit in FIG. 1 not shown, control unit not shown.

The implementation of the invention

According to figure 2, the operation of the device for mixing different grades of oil is as follows (as an example, an example from Fig. 1).

Oil of the first grade, for example, with a high sulfur content, is fed to the highway 1 (see also Fig. 1) connected to the tank farm 2. A better quality oil of the second grade, for example, with a low sulfur content, is located in the tank farm 3. Thus , in the device 4 at the entrance serves two grades of oil. At the output, it is supposed to get three types of mixture supplied to three different outgoing lines: 11, 12 and 13, the sulfur content of which occupy different intermediate positions.

Stage A1. Check the quality of oil of the second grade by the quality control unit 10, standing at the inlet of the auxiliary pump or pump group 5.

Stage A2. Reduce the pressure of oil of the second grade at the inlet of the auxiliary pump or pump group 5,

Stage A3. The pipeline with oil of the second grade is divided into three separate pipelines.

Stage A4. Depending on the level of required sulfur content in the resulting mixture, the positions of the pressure regulators in three separate pipelines are set (see step A3).

Stage A5. The pipeline with oil of the first grade is divided into three separate pipelines.

Stage A6. Mix each of the three pipelines of oil of the first grade with each of the three pipelines of oil of the second grade, respectively.

Stage A7. The resulting three types of mixture are fed to the inlet of booster pumps 61, 62 and 63, respectively.

Stage A8. Set the position of the pressure regulators in three separate pipelines with a mixture of oil.

Stage A9. Quality control of the resulting mixture is carried out in each line by quality control units 101, 102, 103, standing at the inlet of the main pumps 71, 72 and 73.

Step 10. The operation of the pumps and pressure regulators is controlled by a control unit, which receives signals from the quality control units.

The above embodiments of the invention are exemplary and allow you to add new options or modify the described. For example, use stages selectively, rearrange.

Separately, we note the operating modes of this device when adjusting the required composition of the resulting mixture. For definiteness, we give an example of adjustment for the sulfur content in the oil product.

Mode 1. Input Adjustment

A device operation mode is possible when the necessary sulfur content in the resulting mixture is regulated by calculating the required ratio of the mixed components depending on the data obtained using data from in-line sulfur analyzers 104 and 105, i.e., at the input.

Mode 2. Output Adjustment

A device operation mode is possible when the necessary sulfur content in the resulting mixture is controlled by adjusting the consumption of the mixed components depending on the data obtained using data from in-line sulfur analyzers 101, 102 and 103, i.e., at the output. It should be noted that this approach is more accurate, since we accurately know the percentage of sulfur at the entrance to the highway, but there is a delay due to the fact that when a deviation from the required indicator of sulfur content in the mixture and the supply of the corresponding signal to the pressure regulators takes time, while oil flows from the point of regulation of the flow to the point of measuring the concentration of sulfur in the mixture. The time gap can be tens of seconds.

Mode 3. Adjustment at the input and output

A device operation mode is possible when the necessary sulfur content in the resulting mixture is regulated by calculating the required ratio of the mixed components and depending on the data obtained using data from in-line sulfur analyzers 104 and 105, i.e. at the input, and depending on the data received using data from in-line sulfur analyzers 101, 102 and 103, that is, at the output. This mode is the most accurate.

Industrial applicability

The proposed device for mixing different types of oil can be carried out by a specialist in practice and, when implemented, ensures the implementation of the declared purpose, which allows us to conclude that the criterion of "industrial applicability" for the invention is met. The described device for mixing different grades of oil is implemented on the basis of traditional technologies, and the possibility of its implementation is not associated with any additional technical problems.

In accordance with the proposed invention, the applicant has tested this device for mixing different grades of oil.

As storage tanks for oil, reservoirs with a volume of 1000-50000 cubic meters were used.

The task was to ensure a constant mass sulfur content in the mixed oil, namely 0.6%.

The mixed oil main had a constant flow of 908 m ³ / h. This thread was composed of two threads:

1. The main stream of low-sulfur oil with a sulfur content of 0.43%.

2. Additional flow of sulphurous oil from the tank farm with an oil content of 1.43%.

Tests have shown that such a device for mixing different grades of oil provides:

1) reduced requirements for pressure regulators;

2) reduces energy consumption by reducing the pressure on the pressure regulators installed after the auxiliary pump units;

3) when the density of the mixture at 20 ° C in 846 kg / m ³ received the following flow parameters:

- the main flow of low-sulfur oil ranged from 454 m ³ / h (50%) to 726 m ³ / h (80%);

- the additional flow of sulphurous oil from the tank farm ranged from 182 m ³ / h (20%) to 454 m ³ / h (50%).

In another example, oil flows were calculated:

- with the planned volume of mixed oil pumping at 520 m ³ / h, the maximum flow of oil for mixing was 98 m ³ / h;

- with the planned volume of pumped mixed oil at 3474 m ³ / h, the maximum flow of oil for mixing was 654 m ³ / h.

Thus, due to the fact that the device for mixing different grades of oil additionally contains at least one auxiliary pump installed on one of the pipelines for supplying oil from the tank farm and supplying the inlet of the booster pump while ensuring a constant flow rate through the main oil pipeline and as the auxiliary pump, a centrifugal type pump is selected, equipped with a variable frequency drive and providing a lower pressure in comparison with the booster pump, and the claimed first technical result, namely improving operation reliability of the device by reducing pressure on the regulator set pressure after the pump with decreasing auxiliary electricity costs.

An additional useful technical result of the claimed invention is that this device provides:

- the possibility of using a common auxiliary pumping station for work in all possible directions;

- improves mutual work when applying to several highways simultaneously;

- the ability to calculate in advance the position of the pressure regulator according to the current value at the inlet (by density, by viscosity, by sulfur);

- Corrects due to the presence of variable frequency drives the characteristics of the pumps, ensuring the constancy of the parameters in the oil mixture.

Thus, this oil mixing device is recommended for widespread adoption in the oil industry.

Claims (3)

1. A device for mixing different grades of oil, including at least one unit for measuring oil quality, at least one booster pump, at least one pressure regulator and associated flow rate, a device configured to connect it at least two inlet pipelines of oil supply of different grades: going from the main and from the tank farm and at least one outgoing main pipeline of mixed oil containing a main pump, characterized in that The mixing system for different types of oil additionally contains at least one auxiliary pump installed on the oil supply pipe coming from the tank farm, and the auxiliary pump supplies oil to the inlet of the booster pump while ensuring a constant flow rate through the main oil pipeline, while as an auxiliary pump a centrifugal type pump was selected, equipped with a variable frequency drive and providing a lower pressure in comparison with a booster pump. 2. A mixing device for different types of oil according to claim 1, characterized in that a pump designed for the total oil supply in the range from 0 to 50% of the supply of the entire device is selected as an auxiliary pump. 3. The mixing device for different types of oil according to claim 1, characterized in that the mixing device for different types of oil further comprises a control unit, the output of which is connected to the input of a variable frequency drive of the auxiliary pump, and the input of the control unit is connected to units for measuring oil quality, This control unit is adapted to calculate the required amount of swap.

Images