WO2014133419A2

WO2014133419A2 - Assembly for selecting and measuring liquid products to be loaded and system using the same

Info

Publication number: WO2014133419A2
Application number: PCT/RU2014/000129
Authority: WO
Inventors: Vladimir Nikolaevich TROYANCHUK
Original assignee: Obschestvo S Ogranichennoi Otvetstvennostiyu "Siemens"
Priority date: 2013-02-27
Filing date: 2014-02-27
Publication date: 2014-09-04
Also published as: WO2014133419A8; RU2013108890A; WO2014133419A3; RU2560263C2

Abstract

There is provided an assembly for selecting and measuring liquid products to be loaded, comprising: a manifold connected to at least two supply pipelines for supplying at least one product; shutoff means pipeline shutoff means for opening and closing the supply pipelines for supplying at least one product to the manifold; wherein at least one metering means for measuring the product flow rate is mounted downstream from the manifold and adapted to determine the product flow rate; wherein the assembly for selecting and measuring liquid products to be loaded is adapted for self-draining through a loading line disposed downwardly relative to the manifold. Owing to the arrangement of the metering means downstream from the manifold, the number of required metering means can be reduced, while providing reliable and undisturbed operation of the assembly and allowing required redundancy. With such arrangement one metering means or a minimal number thereof can be used for loading the entire range of liquid products, in particular, light petroleum products.

Description

ASSEMBLY FOR SELECTING AND MEASURING LIQUID PRODUCTS TO BE LOADED AND

SYSTEM USING THE SAME

DESCRIPTION The invention relates to an assembly for selecting and measuring liquid products to be loaded, in particular, to an assembly for supplying light petroleum products in systems for selecting and fiscal measuring of petroleum products to be loaded at railcar or truck loading racks operating on gallery or on-spot principle.

According to existing regulatory documents, railcar or truck loading racks operating on gallery or on-spot principle for loading liquid petroleum products shall be provided with assemblies for selecting and fiscal measuring of one or more type of products loaded.

A conventional structure is an assembly for loading petroleum products at railcar or truck loading racks for selecting and measuring more than one type of petroleum products to be loaded, comprising loading stands, liquid meters, cutoff valves, liquid filters, pump assemblies, and the hydraulic unit can be equipped with a densitometer, a temperature sensor, a gas separator, a stepless control cutoff valve and a drainage system, for example, as described in Utility Model RU 28682 U1, published 10.04.2003. The known measuring assembly comprises flow rate metering means disposed in each individual pipeline for supplying each type of product to a loading line formed as a loading stand (see Figure 3 in RU 28682 U1). To avoid entrainment of undissolved gases, a gas separator is mounted upstream of each of the flow rate metering means. An air valve is disposed at the highest point of the loading stand. This system is configured to discharge through a single loading stand one to two types of products, which are not mixed owing to the provision of natural draining of the loading stand lines and the space downstream from the manifold at each change of product.

A problem with this system is that measurement lines with gas separators should be mounted in each petroleum supply pipeline, which is uneconomic because in this case the number of required measurement lines is equal to the multiplication product of the number of loaded products by the number of loading spots. For example, at gallery loading of two 36 car trains with the loading range of 8 products the number of gas separators and measurement lines, including necessary connection piping, will be 72 x 8 = 736. To provide redundancy of flow meters in this system at standard assembly design the number of measurement lines will be 1472. Such a system requires high investments in construction and operation and is not reliable, because failure of any component of the system will result in downtime and great time lost for rebuilding the train. Furthermore, according to manufacturer's requirements in the art flow meters shall be typically set so that the flow passing through a flow meter is directed in a certain way, therefore respective spatial orientation of the flow meter is required, which complicates the equipment, imposes additional constraints on the structure of the assembly for selecting and measuring liquid products to be loaded, and gives no way to reducing the size of the assembly and making it more space-saving (see Figure 1), while, as shown in Figure 1, due to the fact that each measurement line comprises a single flow meter, failure of the latter makes the entire line unable to work and the assembly requires repair thereby delaying the loading until the repair ends. Therefore, failure of a single flow meter makes inoperative the entire assembly for selecting and measuring liquid products to be loaded, as, for example, when a train segment is filled with different products, the segment cannot be filled if the required range of products to be loaded is unavailable.

On the other hand, increasingly higher requirements are currently imposed to ensure undisturbed operation of assemblies for selecting and measuring liquid products to be loaded, which is manifested in the provision of such assemblies with redundant loading lines and metering means. In the example above, this also requires at least duplicity of available equipment, including metering means, for selecting and measuring products to be loaded, that is disproportionate material and capital costs, as well as costs for maintenance of such a complex system, including expenses for routine inspection of the entire measurement system.

Based on the foregoing, an object of the invention is to provide an assembly for selecting and measuring liquid products to be loaded, which ensures more reliable supply of liquid products, has a simpler structure, reduces costs associated with construction, equipment procurement, maintenance and monitoring, while providing a space-saving structure of the assembly.

Another object of the invention is to provide an assembly for selecting and measuring liquid products to be loaded, in which redundancy of measurement lines can be provided to improve undisturbed operation of the assembly in general.

In a first aspect, the present invention relates to an assembly for selecting and measuring liquid products to be loaded, comprising:

a manifold connected to at least two supply pipelines for supplying at least one product;

pipeline shutoff means for opening and closing the supply pipelines for supplying at least one product to the manifold;

a loading line connected to the manifold and supplying a product from the manifold to a loading facility for loading the product into a consumer's reservoir; metering means for measuring the product flow rate, mounted in the loading line downstream from the manifold and adapted to determine the product flow rate;

wherein the assembly for selecting and measuring liquid products to be loaded is adapted for self-draining the manifold and the loading line through the loading line disposed downwardly relative to the manifold.

Owing to the arrangement of the metering means downstream of the manifold, the number of necessary metering means can be reduced by the number of times that is numerically equal to the number of products to be loaded, while providing the required redundancy. Advantageously, the metering means is operable to determine characteristics of the entire range of liquid products being loaded. In this case, at least one metering means can be used for loading the entire range of liquid products, in particular, light petroleum products.

Preferably, the assembly for selecting and measuring liquid products to be loaded further comprises a gas separator mounted in the loading line and/or in at least one of the supply pipelines upstream of the manifold.

The gas separator generally functions in the conventional way and in accordance with existing requirements it is always arranged in the liquid petroleum product supply line upstream of the metering means to ensure its proper operation.

In another preferred embodiment of the assembly for selecting and measuring liquid products to be loaded the gas separator is mounted in the loading line downstream of the manifold, but upstream of the metering means, wherein a bypass line further extends from the gas separator and is connected to the loading line upstream of the metering means.

Terms "upstream" and "downstream", as used herein, refer to the flow direction of liquid product, starting from supply pipelines and ending in the loading stand, pipe or a similar facility for loading a product into consumer's reservoir.

The gas separator is preferably mounted in the loading line downstream from the manifold, but upstream of the metering means, wherein a bypass line further extends from the gas separator and is connected to the loading line downstream from the metering means. With this arrangement the loading line and the manifold can be drained very quickly and completely, which is important when the type or types of loaded products are changed to minimize mixing the products being changed.

To prevent movement of the product over the bypass line along with the main line at basic operation modes, the bypass line extending from the gas separator can be further provided with a shutoff means, and the gas separator can be configured for self-draining through the loading line when the bypass line shutoff means is open.

Furthermore, the bypass line extending from the gas separator can be provided with a pump and at least one shutoff means, and a main line of the loading line can further comprise a shutoff means, in particular a check valve or a cutoff valve.

In a preferred embodiment of the invention the loading line comprises a loading line shutoff means downstream and/or upstream of the metering means.

In general, the assembly for selecting and measuring liquid products to be loaded is adapted for self-draining the metering means through the loading line.

If necessary, the assembly for selecting and measuring liquid products to be loaded may be further provided with one or more air valves.

To provide controlled loading of products the loading line comprises a flow control means.

In an alternative embodiment of an assembly for selecting and measuring liquid products to be loaded a gas separator can be mounted in at least one of the supply pipelines, and the loading line is split, on the portion extending from the manifold, into a main line of the loading line and a bypass line, which are then joined upstream of the metering means; the bypass line is further provided with a pump, and the main line of the loading line further comprises a shutoff means, in particular a check valve or a cutoff valve.

An assembly for selecting and measuring liquid products to be loaded is configured to be controlled by an automatic system for control, emergency protection, monitoring and loading management, containing centralized control stations and a system for date acquisition, analysis and storage. Since such means are known in the art, detailed description of them is omitted. It should nevertheless be noted that the automatic system is provided with appropriate computing and control means and algorithms to ensure opening of respective shutoff means such that to provide selection of the product loaded in accordance with loading schedule and order, draining the loading line and the manifold when the product is changed and, if necessary, continuation of loading, and simultaneously monitoring the amount, head pressure, temperature, pressure, density and other characteristics of the loaded product.

The assembly for selecting and measuring liquid products to be loaded can be improved such that the loading line comprises a flow control means adjustable by the automatic system for control, emergency protection, monitoring and loading management in accordance with the product loading schedule and order and basing on measurements of the product flow rate made by metering means. To ensure undisturbed operation of the assembly for selecting and measuring liquid products to be loaded in case of failures of metering devices, one or more redundant measurement lines can be further provided, which are connected to the loading line upstream and downstream of the metering means disposed in the loading line, wherein the redundant measurement line comprises an additional metering means to measure the product flow rate, and the shutoff means.

In a second aspect the present invention relates to an assembly for selecting and measuring liquid products to be loaded, comprising:

a manifold connected to at least two supply pipelines for supplying at least one product, wherein the manifold has an upper end and a lower end provided with a manifold shutoff means; pipeline shutoff means for opening and closing the supply pipelines for supplying at least one product to the manifold;

a loading line connected with the manifold shutoff means at the lower end of the manifold and supplying the product from the manifold to the loading facility to fill the product into a consumer's reservoir;

a measurement line comprising a product flow rate metering means adapted to determine the product flow rate, wherein the inlet end of the measurement line is connected to the upper part of the manifold, and the outlet end of the measurement line is connected to the loading line downstream of the manifold shutoff means;

wherein the assembly for selecting and measuring liquid products to be loaded is adapted for self-draining the manifold, the measurement line and the loading line through the loading line disposed downwardly relative to the manifold and the measurement line.

The present invention provides a particularly quick draining of the loading line and the manifold when the products are changed. Advantageously, the manifold, the measurement line and the loading line are generally arranged in a descending order, in particular close to the vertical.

The assembly for selecting and measuring liquid products to be loaded further comprises a gas separator mounted in the measurement line and/or in at least one of the supply pipelines. When mounted in the measurement line a gas separator is preferably disposed such that to provide minimal distances of pipe connections, thereby enabling high-speed draining.

The gas separator is particularly preferably mounted at the upper portion of the measurement line upstream of the metering means, wherein a bypass line further extends from the gas separator and is connected to the manifold and has a bypass line shutoff means. In the assembly for selecting and measuring liquid products to be loaded the measurement line can further comprise a shutoff means downstream and/or upstream of the metering means. This embodiment enables maintaining the measurement line and/or replacement of the metering means.

The assembly for selecting and measuring liquid products to be loaded according to the second aspect of the invention is also configured for self-draining the metering means through the loading line.

If necessary, such an assembly, in particular the manifold or the measurement line, is further equipped with one or more air valves.

The assembly can further comprise flow control means, an automatic system for control, emergency protection, monitoring and management of loading, and redundant measurement lines, as disclosed with reference to the first aspect of the present invention.

In a third aspect the present invention relates to an assembly for selecting and measuring liquid products to be loaded, comprising:

a manifold connected to at least two supply pipelines for supplying at least one product, wherein the manifold has an upper end and a lower end;

a measurement line extending from the lower end of the manifold and comprising product flow rate metering means adapted to determine the flow rate of the loaded product and disposed such that the outlet end of the metering means is disposed higher than the inlet end of the metering means; a bypass line of the measurement line, provided with a shutoff means, and

a loading line for supplying the product to a loading facility for loading a consumer's reservoir, the loading line is connected to the measurement line and said bypass line;

wherein the assembly for selecting and measuring liquid products to be loaded is adapted for self-draining the manifold, the measurement line, the bypass line and the loading line through the loading line disposed downwardly relative the manifold, the measurement line and the bypass line.

The assembly can be implemented such that the loaded product enters the metering means as an ascending flow, thereby allowing the use of metering means that require a specific orientation.

Preferably, the metering means is disposed higher than the connection of the measurement line to the lower portion of the manifold.

The assembly for selecting and measuring liquid products to be loaded further comprises a gas separator mounted in the measurement line and/or in at least one of the supply pipelines. In a preferred embodiment, the assembly for selecting and measuring liquid products to be loaded comprises a gas separator, which is mounted in the measurement line, wherein the bypass line of the measurement line extends from the gas separator, and the gas separator is adapted for self-draining through the loading line when the shutoff means of said bypass line is open.

Embodiments and improvements disclosed above with respect to the first and second aspects of the invention are also applicable to the third aspect of the invention.

In another aspect, the invention relates to a system for selecting and measuring liquid products to be loaded with provision of redundancy, comprising at least two assemblies for selecting and measuring liquid products to be loaded and at least one redundant measurement line comprising redundant metering means for measuring the product flow rate and connected by connecting pipes having shutoff means to said at least two assemblies for selecting and measuring liquid products to be loaded.

In general, the present invention increases the margin of safety and reduces constructive and maintenance costs due to the reduced number of components, the failure of each of which will make the entire system inoperative; enhances reliability of the entire assembly by a proportional number of times; reduces expenditures for construction, equipment procurement, maintenance, inspection, etc.

As used herein, term "loading line" refers to a transport line for liquid products from a manifold to a product loading facility, such as a loading/draining pipe. If it is not directly specified in a particular embodiment of the invention, a loading line comprises conventional shutoff means, metering and/or pumping means to supply liquid products to a loading/draining pipe.

Term "manifold" is used herein in its conventional meaning of a portion of a supply line for liquid products, which combines several supply pipelines and includes shutoff means, and is disposed upstream of the loading line.

Both the manifold and the loading line are preferably arranged in a descending order, i.e. their positions vary along the height, thereby ensuring self-draining thereof by gravity.

Term "bypass line" refers to a loop portion of a pipe, which ensures transfer of fluid around one or more metering means, valves or other components. For example, a gas separator bypass line is a line enabling transfer of a fluid around a gas separator.

Measurement line is generally formed by a portion of a supply line, in which the amount, velocity, pressure, and/or other characteristics of the supplied liquid product are metered and registered. As is known in the art a measurement line comprises one or more metering means, and shutoff means to ensure maintenance of the measurement line or closing the same when the supply line is drained or when an associated bypass line is used.

The invention will be further explained in more detail with reference to the accompanying drawings illustrating exemplary embodiments, in which:

Figure 1 shows a conventional assembly for selecting and measuring liquid products to be loaded;

Figure 2 is an embodiment of an assembly for selecting and measuring liquid products to be loaded according to the present invention comprising a gas separator arranged in a loading line, and with a gas separator bypass line;

Figure 3 is an alternative embodiment of an assembly for selecting and measuring liquid products to be loaded according to the present invention, in which gas separators are disposed in supply pipelines;

Figure 4 is another embodiment of an assembly for selecting and measuring liquid products to be loaded according to the present invention, in which a bypass line of metering means is provided;

Figure 5 is an alternative embodiment of an assembly for selecting and measuring liquid products to be loaded comprising a gas separator arranged in a loading line, and a gas separator bypass line provided with a pump;

Figure 6 is an embodiment of an assembly for selecting and measuring liquid products to be loaded according to the present invention comprising gas separators disposed in supply pipelines, and a bypass line provided with a check valve;

Figure 7 is an embodiment of an assembly for selecting and measuring liquid products to be loaded comprising a separate measurement line including a gas separator;

Figure 8 is an embodiment of an assembly for selecting and measuring liquid products to be loaded comprising a separate measurement line, where gas separators are disposed in supply pipelines;

Figure 9 is an embodiment of an assembly for selecting and measuring liquid products to be loaded comprising a separate measurement line having a gas separator and a bypass line;

Figure 10 is an embodiment of an assembly for selecting and measuring liquid products to be loaded comprising a separate measurement line having a bypass line, where gas separators are disposed in supply pipelines;

Figure 11 is an embodiment of an assembly for selecting and measuring liquid products to be loaded comprising a redundant bypass measurement line in the loading line; Figure 12 shows a system comprising two assemblies for selecting and measuring liquid products to be loaded and a redundant bypass measurement line.

The following description of certain exemplary embodiments is intended to explain the principles of the invention and its practical application, thereby enabling others skilled in the art to comprehend the invention in various embodiments and with various modifications, which are suited to a particular application planned. The description does not purport to be exhaustive or limiting the invention to the specific embodiments.

Further, components that are not necessary and/or essential for practicing the present invention, but nevertheless are inherent to usual solutions in the art, are not shown in subsequent drawings for ease of presentation.

In the attached figures, identical components are denoted by the same reference numerals. As shown in Figure 2, an embodiment of an assembly for selecting and measuring liquid products to be loaded comprises supply pipelines 3 entering a manifold 1, and respective pipeline shutoff means 4. The manifold 1 comprises an air valve 10 and is directly adjoined to a loading line 2 including a gas separator 5, a gas separator bypass line 8 with gas separator shutoff means 9, a metering means 6 such as a flow meter, and a flow control means 7. The metering means 6 and the gas separator 5, respectively, are structurally arranged downstream of the manifold 1 in the line for supplying the product to a loading facility. To prevent mixing the products being changed, the entire loading line 2 downstream of the manifold 1, including the metering means 6 and the gas separator 5, has a descending layout to allow natural drainage thereof upon finishing the loading process before changing the products. The gas separator 5 is further provided with a gas separator bypass line 8 connected to the loading line 2 upstream of the metering means 6 with the gas separator shutoff means 9 to allow quick complete drainage of the gas separator 5 and, at the same time, to prevent flow of the product on the bypass line during the main loading period.

The illustrated assembly for selecting and measuring liquid products to be loaded operates as follows. In the initial state all the shutoff means 4, 7 and 9 are closed. The loading line 2 downstream from the manifold 1 is free from product. When the need arises to load a product one of the shutoff means 4 is opened to admit liquid product from the supply pipe 3 into the manifold 1. The product fills the loading line 2 completely from the flow control means 7 to the air valve 10. With this, air is forced out through the air valve 10. The flow control means 7 is opened through appropriate control by the amount necessary to ensure a predetermined supply level. Selected product passes through the metering means 6 and enters loading pipes. Upon reaching a predetermined filling level and if information about changing the product for subsequent loading is available, the shutoff means 4 is closed, the air valve 10 is opened, the bypass line 8 shutoff means 9 is opened to drain the product from the gas separator 5, and the product releases the loading line 2 and the manifold 1 by gravity, while the metering means 6 measures the amount of product during draining. Once the draining process has been finished, all the shutoff means 7, 9 are closed, and the system goes into waiting mode for subsequent loading. If no change of the product is scheduled during subsequent loading, upon finishing current loading the flow control means 7 is closed and the supply line downstream thereof is drained, while the loading line 2 between the manifold 1 and the flow control means 7 stays filled until next loading cycle, therefore its filling is not required before the next loading operation.

Use of the invention will reduce the number of metering means or measurement lines at railcar or truck loading racks operating on gallery or on-spot principle for measuring more than one type of petroleum products to be loaded, reduce investments in the construction and operation of the racks, and increase reliability of the system.

Figure 3 shows an assembly for selecting and measuring liquid products to be loaded, in which unlike the assembly according to Figure 2 the gas separators 5 are arranged in the supply pipelines 3 upstream of the pipeline shutoff means 4; furthermore, the loading line comprises a loading line shutoff means 11 to allow maintaining the loading line and/or the metering means 6, and a flow control means 7 which is controlled to provide a predetermined loading of product. This embodiment ensures a quick discharging of the loading line 2, while respective gas separators 5 can stay filled with the product.

In the embodiment illustrated in Figure 4, an assembly for selecting and measuring liquid products to be loaded comprises supply pipelines 3 entering into the manifold 1, and respective pipeline shutoff means 4. The manifold 1 comprises an air valve 10, and a loading line 2 including a gas separator 5, a gas separator bypass line 8 with shutoff means 9, metering means 6 such as a flow meter, and a flow control means 7 directly adjoins the manifold 1. To ensure maintaining the metering means 6 there are provided loading line shutoff means 11 upstream and downstream of the metering means 6; wherein the bypass line 8 is connected to the loading line 2 downstream of the metering means 6 and the respective shutoff means 11. In the illustrated embodiment, the metering means 6 and the gas separator 5 are also arranged downstream from the manifold 1 on the line for supplying product to the loading facility. At the same time, to prevent mixing of products being changed, the entire loading line 2 downstream of the manifold 1, including the metering means 6 and the gas separator 5, has a descending layout to allow natural discharge thereof upon finishing the loading process before changing the products. The gas separator 5 is further provided with a bypass line 8 with a shutoff means 9 to allow quick complete discharging of the gas separator 5. The assembly for selecting and measuring liquid products to be loaded products shown in Figure 4 operates as follows.

Initially, all components of the supply unit, including the manifold 1 , the gas separator 5, and the loading line 2, are free from a product. When the need arises to load a product, the shutoff means 4 of the pipe 3 and shutoff means 11 of the loading line 2, if available, are opened. The product fills the whole of the loading line 2 until the flow control means 7; the shutoff means 9 of the bypass line 8 is also open for the time of loading the loading line 2, and all air is forced out through the air valve 10. Once the loading line 2 has been filled, the shutoff means 9 is closed, and the flow control means 7 is opened by the amount necessary to ensure a predetermined supply level. Selected product passes through the gas separator 5 of the metering means 6 and arrives for loading. Upon reaching a predetermined filling level and if the product is to be changed for subsequent loading, the shutoff means 4 of the pipe 3 is closed, the air valve 10 and the shutoff means 9 are opened, so the product contained in the manifold 1 and the gas separator 5 flows through the bypass line 8, the flow control means 7 and further to the loading pipe, while the metering means 6 is also drained. The draining process takes place through two paths 2, 8 thereby providing highly complete drainage. Once the draining process has been finished all the shutoff means 7, 9, and 11 , if available, are closed, and the system goes into waiting mode for subsequent loading. If no change of product is scheduled In the subsequent loading, after finishing current loading the flow control means 7 and the shutoff means 4 are closed, and the supply line is drained only downstream from the flow control means 7, while the loading line 2 stays filled until next loading cycle.

Use of the invention will reduce time and ensure highly complete drainage of lines at railcar or truck loading racks operating on gallery or on-spot principle for measuring more than one type of petroleum products to be loaded with two or more loading spots, while keeping the requirement of non-mixing the products when they are changed.

In the embodiment illustrated in Figure 5 an assembly for selecting and measuring liquid products to be loaded includes supply pipelines 3 entering into a manifold 1, and respective pipeline shutoff means 4. The manifold 1 is provided with an air valve 10, and a loading line 2 including a gas separator 5 and a flow control means 7, adjoins directly to the manifold 1, wherein a bypass line 8 is connected to the loading line 2 upstream of the metering means 6. The metering means 6 and the gas separator 5, respectively, are structurally arranged downstream of the manifold 1 at the line for supplying the product to the loading facility. At the same time, to prevent mixing the products being changed, the entire loading line 2 downstream from the manifold 1, including the metering means 6 and the gas separator 5, has a descending layout to allow natural discharge thereof upon finishing the loading process before changing products.

The gas separator 5 is further provided with a bypass line 8 with shutoff means 9 to allow quick complete drainage of the gas separator 5, and to accelerate draining and to maintain an excess pressure at the metering means 6 in the loading line 2 the bypass line 8 further comprises a pump 12, and the loading line 2 comprises a check valve 13 or another device that restricts the reverse flow of the product in the loading line 2 when the pump is running. In general, operation of the assembly is similar to that described with reference to Figure 2, wherein the pump 12 is activated simultaneously with opening the shutoff means 3, and at the same time the check valve 13 or another device that restricts the reverse flow of the product in the loading line 2 is closed.

As shown in Figure 6 the above embodiment may be modified such that gas separators are arranged upstream of the manifold 1. In this case there is no need to discharge the gas separators when product is changed. Use of the assembly according to Fig. 6 will greatly reduce the time for draining the loading line 2, stabilize the flow rate and pressure of the product entering the metering means 6.

Figure 7 shows another embodiment of an assembly for selecting and measuring liquid products to be loaded in one variant which includes supply pipelines 3 entering into a manifold 1, and respective pipeline shutoff means 4, wherein the lower end of the manifold 1 is provided with manifold shutoff means 16, to which a loading line 2 including a flow control means 7 directly adjoins.

To the upper end of the manifold a measurement line 15 is connected, which comprises a gas separator 5 provided with a bypass line 8 having shutoff means 9 and connected to the manifold 1. The measurement line 15 also comprises metering means 6 such as a flow meter, and measurement line shutoff means 14 upstream and downstream of the metering means 6.

In the illustrated variant, the manifold, the measurement line 15 and the loading line 2 are arranged in a descending layout to allow natural discharge thereof upon finishing the loading process before changing products.

The gas separator 5 is disposed near the upper part of the manifold 1 upstream of the metering means 6.

The assembly for selecting and measuring liquid products to be loaded, as shown in Figure 7, operates as follows. In the initial state, all the shutoff means 4, 7, 9, 14 (if available) and 16 are closed. Components of the supply unit, including the manifold 1 , the gas separator 5, the measurement line 15, the bypass line 8 and loading line 2 are free from product.

When the need arises to load a product, the shutoff means 4, the shutoff means 9 of the bypass line 8, the measurement line shutoff means 14, if available, and the manifold shutoff means 16 are opened. Product fills the entire supply line until the flow control means 7 and forces out air through the air valve 10. Once the loading has been finished, the shutoff means 9 of the bypass line 8 and the air valve 10 are closed, and the flow control means 7 is opened by the amount necessary to ensure a predetermined supply level. Selected product passes through the gas separator 5, the measurement line 15 and enters into loading pipes, while the metering means 6 is used for measuring and monitoring characteristics of the product.

Upon reaching a predetermined filling level and if the product is to be changed for subsequent loading, the shutoff means 4 is closed, the air valve 10 and the shutoff means 9 of the bypass line 8 are opened, so the product releases by gravity components of the assembly for selecting and measuring liquid products to be loaded, wherein the drainage process takes place through the loading line 2 on two parallel lines: one line is formed by the measurement line 15, and the other line is formed by the manifold 1 with the shutoff means 16. Once the drainage process has been finished, all the shutoff means 9, 14, 7, 16 are closed and the system goes to waiting mode for subsequent loading.

If no change of product is scheduled in the subsequent loading, upon finishing current loading the flow control means 7 is closed, and the supply line is drained downstream of the flow control means 7, while the loading line 2 and the measurement line 15, if necessary, and the manifold 1 stay filled until next loading cycle, and no loading thereof is required before loading operation.

In this embodiment, the measurement line 15, the manifold 1 and the gas separator can be discharged simultaneously or in any optimal sequence to ensure required drainage.

Product discharged from the lines can be measured by calibrating the volume of the drained lines and adding the volume to the amounts that have been loaded.

The embodiment shown in Figure 7 reduces the vertical extent of the assembly, time for draining product at railcar or truck loading racks operating on gallery or on-spot principle, for measuring more than one type of petroleum products to be loaded with two or more loading spots, while keeping the requirement of non-mixing the products when they are changed. The above variant may be modified such that the gas separators 5 are arranged in upstream of the manifold (see Figure 8); this eliminates the need to discharge the gas separator, while the measurement line 15 and the manifold 1 may be discharged in any sequence and particularly quick.

Figure 9 shows an alternative embodiment of an assembly for selecting and measuring liquid products to be loaded. In the illustrated embodiment, metering means 6 is arranged in a measurement line at an ascending flow portion, which further eliminates retention of undissolved gases and air in the sensitive area of the flow meter.

The assembly for selecting and measuring liquid products to be loaded, as shown in Figure 9, comprises supply pipelines 3 entering into a manifold 1, and respective pipeline shutoff means 4. The manifold 1 is provided with an air valve 10, and the manifold is connected to a measurement line 15 and to a bypass line 8, which go over into a loading line 2, respectively.

The measurement line comprises a gas separator 5 and, disposed downstream thereof, a measurement line shutoff means 14 and a metering means 6. In the embodiment shown in Figure 9, the measurement line is formed as an ascending line to ensure the flow of loaded product upwards and comprises an additional air valve 10. A bypass line 8 comprising a shutoff means 9 and connected to the loading line 2 is also adjoins to the junction of the measurements line 15 and the manifold 1.

With this, to prevent mixing when products are changed the measurement line 15 and the manifold 1 are designed in a descending layout to allow natural discharge thereof upon finishing the loading process before changing products.

The assembly for selecting and measuring liquid products to be loaded as shown in Figure 9 operates as follows.

In the initial state, all the shutoff means 4, 7, 9, 14 are closed and all the components of the assembly are free of product being loaded.

When the need arises to load a product, they are filled with the product; to this end the shutoff means 9 of the bypass line 8, the shutoff means 14 of the measurement line 15, and the shutoff means 4 are opened. The product fills the assembly for selecting and measuring liquid products to be loaded until the flow control means 7, while air is forced out through the air valves 10.

Once the filling has been finished, the shutoff means 9 of the bypass line 8 is closed, and the flow control means 7 is opened by the amount necessary to ensure a predetermined supply level. Selected product passes through the gas separator 5, the measurement line 15, and the flow control means 7 and enters into loading pipes. Upon reaching a predetermined filling level and if the product shall be changed for subsequent loading, the shutoff means 4 is closed, the air valves 10 and the shutoff means 8 of the bypass line 9 are opened, and the loaded product releases by gravity all components of the assembly for selecting and measuring liquid products to be loaded.

Particularly quick and complete drainage of the assembly is achieved owing to the fact that it can be discharged optionally via one or two lines that are formed by the measurement line 15 and the bypass line 8, respectively.

Once the draining process has been finished, all the shutoff means 7, 9, and 14, if available, are closed, and the system goes into waiting mode for subsequent loading. If no change of the product during subsequent loading is scheduled, upon finishing current loading the flow control means 7 and the shutoff means 4, if necessary, are closed, and the supply line is drained only downstream of the flow control means 7, therefore, there is no need to fill components of the assembly for selecting and measuring liquid products to be loaded before subsequent loading.

Use of this embodiment will improve the measurement accuracy owing to eliminated retention of undissolved air and gas in the sensitive area of the metering means 6 of the assembly for selecting and measuring liquid products to be loaded for fiscal measuring the loaded product at railcar or truck loading racks operating on gallery or on-spot principle, for measuring more than one type of petroleum products to be loaded, with two or more loading spots, while keeping the requirement of non-mixing the products when they are changed.

The above embodiment may be modified such that the gas separators 5 are arranged upstream of the manifold (see Figure 10); this eliminates the need for draining the gas separator, while the measurement line 15 and the manifold 1 may be discharged in any sequence and particularly quickly.

Figure 11 shows an alternative embodiment of an assembly for selecting and measuring liquid products to be loaded, wherein the loading line 2 comprises a redundant bypass measurement line 17 connected to the loading line upstream and downstream from the metering means 6; the redundant bypass measurement line 17 is activated by opening shutoff means 18 of the redundant bypass measurement line 17 when the shutoff means 11 of the loading line 2 are closed. It is also possible that the shutoff means 11 and 18 are open simultaneously. In this case, characteristics of the loaded liquid product are measured both by the metering means 6 of the loading line 2, and the metering means 6 of the redundant bypass measurement line 17. In all other respects the assembly for selecting and measuring liquid products to be loaded, as shown in Figure 11, and its components operate as described above.

Figure 12 shows an example of a system comprising two assemblies for selecting and measuring liquid products to be loaded, as well as a redundant bypass measurement line. In the illustrated embodiment the system comprises two assemblies according to Figure 1, but in principle any of the above described assemblies may be advantageously combined. In general, operation of components of the assemblies for selecting and measuring liquid products to be loaded corresponds to the above description, wherein by closing or opening respective shutoff means 18 of the redundant bypass measurement line 17 the latter is connected to the left or right assembly for selecting and measuring liquid products to be loaded, shown in Figure 12. The above implementation provides a simple design of a system for selecting and measuring liquid products to be loaded, comprising at least two assemblies for selecting and measuring liquid products to be loaded, which provides required redundancy of metering means and undisturbed supply of liquid products loaded, in particular light petroleum products.

It shall be understood that the above description is illustrative, and the claims cover all modifications or alternatives, which a person of ordinary skill in the art could anticipate.

List of reference numerals

1 - manifold

2 - loading line

3 - supply pipeline

4 - shutoff means of supply pipeline

5 - gas separator

6 - metering means

7 - flow control means

8 - bypass line

9 - shutoff means of bypass line 10 - air valve

11 - shutoff means of loading line 12 - pump

13 - check valve

14 - shutoff means of measurement line 15 - measurement line

16 - shutoff means of manifold

17 - redundant bypass measurement line

Claims

1. An assembly for selecting and measuring liquid products to be loaded, comprising:

a loading line connected to the manifold and supplying the product from the manifold to a loading facility for loading the product into a consumer's reservoir;

metering means for measuring a product flow rate, mounted in the loading line downstream from the manifold and adapted to determine the product flow rate;

wherein the assembly for selecting and measuring liquid products to be loaded is designed for self-draining the manifold and the loading line through the loading line disposed downwardly relative to the manifold.

2. The assembly according to claim 1, characterized in that the assembly further comprises a gas separator mounted in the loading line and/or in at least one of the supply pipelines, and/or

a gas separator is mounted in at least one of the supply pipelines and the loading line is split, on the portion extending from the manifold, into a main line of the loading line and a bypass line, which are then joined upstream of the metering means; the bypass line is further provided with a pump, and the main line of the loading line further comprises a shutoff means such as a check valve or a cutoff valve.

3. The assembly according to claim 2, characterized in that the gas separator is mounted in the loading line downstream of the manifold, but upstream of the metering means, wherein a bypass line further extends from the gas separator and is connected to the loading line upstream of the metering means, or

the gas separator is mounted in the loading line downstream of the manifold, but upstream of the metering means, wherein a bypass line further extends from the gas separator and is connected to the loading line downstream of the metering means.

4. The assembly according to claim 3, characterized in that

the bypass line extending from the gas separator is further provided with a control valve, and the gas separator is adapted for self-draining through the loading line when the bypass line shutoff means is open, or the bypass line extending from the gas separator is further provided with a pump and with at least one shutoff means, and a main line of the loading line further comprises a shutoff means such as a check valve or a cutoff valve.

5. The assembly according to claim 1 , characterized in that

the loading line comprises a loading line shutoff means downstream and/or upstream of the metering means, and/or

the assembly is adapted for self-draining the metering means through the loading line, and/or the assembly further comprises one or more air valves,

and/or the loading line comprises a flow control means, and/or

the assembly is configured to be controlled by an automatic system for control, emergency protection, monitoring and loading management, wherein the automatic system for control, emergency protection, monitoring and loading management comprises centralized control stations and a system for date acquisition, analysis and storage, wherein the loading line comprises a flow control means adjustable by the automatic system for control, emergency protection, monitoring and loading management basing on measurements of the product flow rate by metering means in accordance with the product loading schedule and order, and/or

the assembly further comprises a redundant measurement line connected to the loading line upstream and downstream of the metering means disposed in the loading line, wherein the redundant measurement line comprises an additional metering means to measure the product flow rate and the shutoff means.

6. An assembly for selecting and measuring liquid products to be loaded, comprising:

a manifold connected to at least two supply pipelines for supplying at least one product, wherein the manifold has an upper end and a lower end provided with manifold shutoff means;

a loading line connected with the manifold shutoff means at the lower end of the manifold and supplying the product from the manifold to the loading facility for loading the product into a consumer's reservoir;

a measurement line comprising product flow rate metering means adapted to determine the product flow rate, wherein the inlet end of the measurement line is connected to the upper part of the manifold, and the outlet end of the measurement line is connected to the loading line downstream of the manifold shutoff means;

7. The assembly according to claim 6, characterized in that

the assembly further comprises a gas separator mounted in the measurement line and/or in at least one of the supply pipelines, and/or

the gas separator is mounted at the upper portion of the measurement line upstream of the metering means, wherein a bypass line further extends from the gas separator, the bypass line is connected to the manifold and comprises a bypass line shutoff means, and/or

the measurement line further comprises a shutoff means downstream and/or upstream of the metering means, and/or

the assembly is adapted for self-draining the metering means through the loading line, and/or the assembly further comprises one or more air valves, and/or

the loading line further comprises a flow control means, and/or

the assembly further comprises a redundant measurement line connected to the measurement line upstream and downstream of the metering means disposed in the measurement line, wherein the redundant measurement line comprises an additional metering means to measure the product flow rate and the shutoff means.

8. The assembly according to any one of claims 6 or 7, characterized in that the assembly is configured to be controlled by an automatic system for control, emergency protection, monitoring and loading management, wherein the automatic system for control, emergency protection, monitoring and loading management comprises centralized control stations and a system for data acquisition, analysis and storage, wherein the loading line comprises a flow control means adjustable by automatic system for control, emergency protection, monitoring and loading management basing on measurements of the product flow rate by metering means in accordance with the product loading schedule and order.

9. An assembly for selecting and measuring liquid products to be loaded, comprising:

a manifold connected to at least two supply pipelines for supplying at least one product, wherein the manifold has an upper end and a lower end; pipeline shutoff means for opening and closing the supply pipelines for supplying at least one product to the manifold;

a measurement line extending from the lower end of the manifold and comprising a product flow rate metering means adapted to determine the flow rate of the loaded product and disposed such that the outlet end of the metering means is disposed higher than the inlet end of the metering means; a bypass line of the measurement line, provided with a shutoff means, and

a loading line to supply the product to a loading facility for loading a consumer's reservoir, wherein the loading line is connected to the measurement line and to said bypass line;

10. The assembly according to claim 9, characterized in that the metering means is disposed higher than the joining point of the measurement line to the lower portion of the manifold, and/or the assembly further comprises a gas separator mounted in the measurement line and/or in at least one of the supply pipelines, wherein the gas separator is mounted in the measurement line, the bypass line of the measurement line extends from the gas separator, and the gas separator is adapted for self-draining through the loading line when the shutoff means of said bypass line is open, and/or

the loading line further comprises a flow control means.

11. The assembly according to any one of claims 9 or 10, characterized in that the assembly is configured to be controlled by an automatic system for control, emergency protection, monitoring and loading management.

12. The assembly according to claim 11, characterized in that the automatic system for control, emergency protection, monitoring and loading management comprises centralized control stations and a system for data acquisition, analysis and storage, wherein the loading line comprises a flow control means adjustable by the automatic system for control, emergency protection, monitoring and loading management basing on measurements of the product flow rate by metering means in accordance with the product loading schedule and order.

13. The assembly according to claim 9, characterized in that the assembly further comprises a redundant measurement line connected to the measurement line upstream and downstream of the metering means disposed in the measurement line, wherein the redundant measurement line comprises an additional metering means to measure the product flow rate and the shutoff means.

14. An assembly for selecting and measuring liquid products to be loaded, comprising an assembly for selecting and measuring liquid products to be loaded according to any one of claims 1 to 13 and a redundant measurement line connected to said assembly and comprising an additional metering means to measure the product flow rate, and the shutoff means.

15. A system for selecting and measuring liquid products to be loaded with provision of redundancy, comprising

at least two assemblies for selecting and measuring liquid products to be loaded according to any one of claims 1 to 13,

and at least one redundant measurement line, which comprises redundant metering means for measuring the product flow rate and is connected by connecting piping having shutoff means to said at least two assemblies for selecting and measuring liquid products to be loaded.