MODELLING OF OPERATING AND/OR DIMENSIONING PARAMETERS OF A GAS TREATMENT PLANT

Abstract

The invention relates to methods and systems for determining operating and/or dimensioning parameters of a gas treatment plant including at least one gas treatment unit as well as methods and systems for generating a request to initiate the determination of operating and/or dimensioning parameters of a gas treatment plant. The invention further relates to a computer program and non-volatile or non-transitory storage medium with the computer program, which when executed on one or more processors, performs one or more of the methods.

Claims

1. A method for determining operating and/or dimensioning parameters of a gas treatment plant (10) for treating a gaseous inlet stream (16) with a treatment solution to provide a treated outlet stream (20) including one or more gas treatment units (12, 14, 30, 38), the method comprising the steps of: a. receiving (S3, S9), via an interface unit (130-1), a request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant (10), wherein the request comprises gas treatment unit input parameters for the one or more gas treatment unit(s), wherein the gas treatment unit input parameters include at least one relative parameter which is independent of the plant throughput, b. initializing (S6, S12), via a determination processing unit (130-2), a digital model of the gas treatment plant (10) based on the gas treatment unit input parameters and including a relation of the at least one relative parameter to a corresponding parameter, wherein the corresponding parameter is dependent on the plant throughput or dependent on a gas treatment unit geometry and is a result of the relation to the at least one relative parameter, wherein the digital model characterizes the mass and heat transfer in the gas treatment plant (10) including one or more gas treatment unit(s) (12, 14, 30, 38), c. determining (S7, S13), via the determination processing unit (130-2), operating and/or dimensioning parameters of the gas treatment plant (10) including the corresponding parameter based on the digital model, d. outputting (S8, S15), via an output interface (130-4), the operating and/or dimensioning parameters including the corresponding parameter dependent on the plant throughput or dependent on the gas treatment unit geometry.

2. The method of claim 1, wherein one of the one or more gas treatment units (12, 14, 30, 38) is an absorber (12), wherein absorber input parameters are received which include at least one of the following relative parameters: i. a composition specifying a proportion of one or more depleted gas component(s) in the treated outlet stream, ii. a loading factor indicating a distance to an equilibrium capture capacity of the treatment solution in the absorber, iii. an acceptable hydraulic load indicating an acceptable hydraulic operational regime in the absorber.

3. A method for determining operating and/or dimensioning parameters of a gas treatment plant (10) for treating a gaseous inlet stream (16) with a treatment solution to provide a treated outlet stream (20) including one or more gas treatment unit(s) (12, 14, 30, 38), wherein one of the one or more gas treatment unit(s) (12, 14, 30, 38) is an absorber (12), the method comprising the steps of: a. receiving (S3, S9), via an interface unit (130-1), a request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant (10), wherein the request comprises absorber input parameters, wherein the absorber input parameters include a loading factor indicating a distance to an equilibrium capture capacity of the treatment solution in the absorber, b. initializing (S6, S12), via a determination processing unit (130-2), a digital model of the gas treatment plant (10) based on the absorber input parameters and including a relation of the loading factor to a flow rate, wherein the digital model characterizes the mass and heat transfer in the gas treatment plant (10) including the absorber (12), c. determining (S7, S13), via the determination processing unit (130-2), operating and/or dimensioning parameters of the gas treatment plant (10) including the flow rate based on the digital model, d. outputting (S8, S15), via an output interface (130-4), the operating and/or dimensioning parameters including the flow rate.

4. The method of claim 3, wherein the absorber input parameters further include at least one of the following relative parameters: i. a composition specifying a proportion of one or more depleted gas component(s) in the treated outlet stream, ii. an acceptable hydraulic load indicating an acceptable hydraulic operational regime in the absorber.

5. The method of claim 2, wherein the absorber input parameters include the loading factor, which is related to an actual loading and an equilibrium loading.

6. The method of claim 2, wherein the absorber input parameters include the loading factor, which is determined by an extremum of the ratio of actual loading to equilibrium loading or vice versa along the absorber height or at the absorber bottom.

7. The method of claim 2, wherein the loading factor of the treatment solution is determined based on one or more gas component(s) to be absorbed from the inlet stream (16), wherein in case of more than one gas component to be absorbed from the inlet stream (16) the loading factor is determined as combined loading factor including the more than one gas components to be absorbed.

8. The method of claim 1, wherein one of the one or more gas treatment units (12, 14, 30, 38) includes a regenerator (14), which comprises at least one reboiler for regenerating the treatment solution and feeding the regenerated treatment solution back into an absorber (12), wherein the request further comprises regenerator input parameters including at least one of the following relative parameters: i. a fraction quality of the regenerated treatment solution, a strip steam ratio, or a loading factor indicating the distance to the equilibrium capture capacity of the regenerated treatment solution at the absorber top, ii. an acceptable hydraulic load indicating an acceptable hydraulic operational regime in the regenerator.

9. The method of claim 1, wherein determining (S7, S13) the dimensioning and/or operating parameters includes using an equation-based solution method or a sequential solution method for the digital model.

10. The method of claim 1, wherein the equation-based solution method includes all equations of the digital model in a single system of equations, which are solved simultaneously.

11. The method of claim 1, wherein the request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant (10) is received (S3, S9) from a client device (110), wherein the client device (110) comprises a input unit (110-1) and wherein the interface unit (130-1) is part of the determination server (130) or wherein the input unit (110-1) and the interface unit (130-1) are part of the client device (110).

12. The method of claim 1, wherein the gas treatment unit input parameters are provided according to a permission object, wherein the permission object defines which gas treatment unit input parameters are provided as relative parameter or as corresponding parameter.

13. The method of claim 1, wherein for the initialization of the digital model thermodynamic parameters are provided (S12) via a database unit, wherein the thermodynamic parameters are derived from measurements of thermodynamic properties of gas treatment plants (10) under operating conditions.

14. The method of claim 1, wherein a validation step is performed for the at least one relative parameter before and/or after receipt of the request, wherein the at least one relative parameter is valid, if it lies within a predefined range.

15. A system for determining operating and/or dimensioning parameters of a gas treatment plant (10) for treating a gaseous inlet stream (16) with a treatment solution to provide a treated outlet stream (20) including one or more gas treatment units (12, 14, 30, 38), wherein the system is configured to: a. receive a request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant (10), wherein the request comprises gas treatment unit input parameters for the one or more gas treatment unit(s), wherein the gas treatment unit input parameters include at least one relative parameter which is independent of the plant throughput, b. initialize a digital model of the gas treatment plant (10) based on the gas treatment unit input parameters and including a relation of the at least one relative parameter to a corresponding parameter, wherein the corresponding parameter is dependent on the plant throughput or dependent on the gas treatment unit geometry and is a result of the relation to the at least one relative parameter, wherein the digital model characterizes the mass and heat transfer in the gas treatment plant (10) including the one or more gas treatment unit(s) (12, 14, 30, 38), and which is configured to operating and/or dimensioning parameters of the gas treatment plant (10) including the corresponding parameter based on the digital model, and c. output the operating and/or dimensioning parameters including the corresponding parameter dependent on the plant throughput or dependent on the gas treatment unit geometry.

16. A system for determining operating and/or dimensioning parameters of a gas treatment plant (10) for treating a gaseous inlet stream (16) with a treatment solution to provide a treated outlet stream (20) including one or more gas treatment units (12, 14, 30, 38), wherein one of the one or more gas treatment unit(s) (12, 14, 30, 38) is an absorber (12), wherein the system is configured to: a. receive a request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant (10), wherein the request comprises absorber input parameters, wherein the absorber input parameters include a loading factor indicating the distance to the equilibrium capture capacity of the treatment solution in the absorber, b. to initialize a digital model of the gas treatment plant (10) based on the absorber input parameters and including a relation of the loading factor to a flow rate, wherein the digital model characterizes the mass and heat transfer in the gas treatment plant (10) including the absorber, and configured to determine operating and/or dimensioning parameters of the gas treatment plant (10) including the flow rate based on the digital model, c. to output the operating and/or dimensioning parameters including the flow rate.

17. A method for generating a request to initiate the determination of operating and/or dimensioning parameters of a gas treatment plant (10) for treating a gaseous inlet stream with a treatment solution to provide a treated outlet stream including one or more gas treatment units (12, 14, 30, 38), wherein the generation includes providing gas treatment unit input parameters according to a permission object, wherein the permission object defines which gas treatment unit input parameters are provided as relative parameter, wherein such relative parameter is independent of the plant throughput and relates to at least one corresponding parameter that depends on the plant throughput or depends on the gas treatment unit geometry.

18. (canceled)

19. (canceled)

20. A non-transitory computer-readable storage medium having instructions encoded thereon that, when executed on one or more processing device(s), cause the processor(s) to perform the steps according to the method of claim 1.

21. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0143] Example embodiments of the present invention are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only particular embodiments of the present invention and are therefore not to be considered limiting of its scope. The present invention may encompass other equally effective embodiments.

[0144] FIG. 1 shows an example flowsheet of an acid gas removal plant including one absorber-regenerator cycle,

[0145] FIG. 2 shows an example embodiment of the method for determining operating and/or dimensioning parameters of a gas treatment plant in a client device-server set-up;

[0146] FIG. 3 shows a further example embodiment of the method for determining operating and/or dimensioning parameters of a gas treatment plant;

[0147] FIG. 4 shows an example embodiment of the system for determining operating and/or dimensioning parameters of a gas treatment plant;

[0148] FIG. 5 shows an example embodiment of a graphical user interface to generate the process specific input parameters for the method;

[0149] FIG. 6 illustrates an example embodiment for determining the CO.sub.2 loading factor via the ratio of the actual loading to the equilibrium loading in the liquid phase;

[0150] FIG. 7 shows the liquid phase temperature behavior illustrating absorber height versus temperature dependency for different flow rates;

[0151] FIG. 8 shows the gas phase CO.sub.2 content behavior illustrating absorber height versus CO.sub.2 content dependency for different flow rates;

[0152] FIG. 9 shows the loading factor CO.sub.2 behavior illustrating absorber height versus loading factor dependency for different flow rates; and

[0153] FIG. 10 shows the convergence behavior illustrating the number of iterations versus flow rate.

DETAILED DESCRIPTION OF EMBODIMENTS

[0154] FIG. 1 shows an example flowsheet of an acid gas removal plant 10 including one absorber-regenerator cycle,

[0155] The flowsheet is defined by the combination of single unit operations or gas treatment units, like mixer, heater/cooler, flash stage, equilibrium stage column and rate based column. The single unit operations are connected by streams or interconnections. Recycle streams or interconnections may be present which lead to the fact that changes in one unit operation have an impact on some or all unit operations in the flowsheet.

[0156] The acid gas removal plant 10 of FIG. 1 includes an absorber 12 and a desorption column 14 as regenerator for the treatment solution. The treatment solution may include an aqueous amine solution as absorption medium. Absorption mediums comprise at least one amine. The following amines are preferred: [0157] (i) amines of formula I:

NR.sup.1(R.sup.2).sub.2   (I)

where R1 is selected from C2-C6-hydroxyalkyl groups, C1-C6-alkoxy-C2-C6-alkyl groups, hydroxy-C1-C6-alkoxy-C2-C6-alkyl groups and 1-piperazinyl-C2-C6-alkyl groups and R2 is independently selected from H, C1-C6-alkyl groups and C2-C6-hydroxyalkyl groups; [0158] (ii) amines of formula II:

R.sup.3R.sup.4N—X—NR.sup.5R.sup.6   (II)

where R3, R4, R5 and R6 are independently of one another selected from H, C1-C6-alkyl groups, C2-C6-hydroxyalkyl groups, C1-C6-alkoxy-C2-C6-alkyl groups and C2-C6-aminoalkyl groups and X represents a C2-C6-alkylene group, —X1—NR7—X2— or —X1—O—X2—, where X1 and X2 independently of one another represent C2-C6-alkylene groups and R7 represents H, a C1-C6alkyl group, C2-C6-hydroxyalkyl group or C2-C6-aminoalkyl group; [0159] (iii) 5- to 7-membered saturated heterocycles which have at least one nitrogen atom in the ring and may comprise one or two further heteroatoms selected from nitrogen and oxygen in the ring, and [0160] (iv) mixtures thereof.

[0161] Specific examples are: [0162] (i) 2-aminoethanol (monoethanolamine), 2-(methylamino)ethanol, 2-(ethylamino)ethanol, 2-(n-butylamino)ethanol, 2-amino-2-methylpropanol, N-(2-aminoethyl)piperazine, methyldiethanolamine, ethyldiethanolamine, dimethylaminopropanol, t-butylaminoethoxyethanol, 2-amino-2-methylpropanol;

[0163] (ii) 3-methylaminopropylamine, ethylenediamine, diethylenetriamine, triethylenetetramine, 2,2-dimethyl-1,3-diaminopropane, hexamethylenediamine, 1,4-diaminobutane, 3,3-iminobispropylamine, tris(2-aminoethyl)amine, bis(3-dimethylaminopropyl)amine, tetramethylhexamethylenediamine; [0164] (iii) piperazine, 2-methylpiperazine, N-methylpiperazine, 1-hydroxyethylpiperazine, 1,4-bishydroxyethylpiperazine, 4-hydroxyethylpiperidine, homopiperazine, piperidine, 2-hydroxyethylpiperidine and morpholine; and [0165] (iv) mixtures thereof.

[0166] In a preferred embodiment the absorption medium comprises at least one of the amines monoethanolamine (MEA), methylaminopropylamine (MAPA), piperazine, diethanolamine (DEA), triethanolamine (TEA), diethylethanolamine (DEEA), diisopropylamine (DIPA), aminoethoxyethanol (AEE), dimethylaminopropanol (DIMAP) and methyldiethanolamine (MDEA) or mixtures thereof.

[0167] The amine is preferably a sterically hindered amine or a tertiary amine. A sterically hindered amine is a secondary amine in which the amine nitrogen is bonded to at least one secondary carbon atom and/or at least one tertiary carbon atom; or a primary amine in which the amine nitrogen is bonded to a tertiary carbon atom. One preferred sterically hindered amine is tbutylaminoethoxyethanol. One preferred tertiary amine is methyldiethanolamine.

[0168] When the amine is a sterically hindered amine or a tertiary amine the absorption medium preferably further comprises an activator. The activator is generally a sterically unhindered primary or secondary amine. In these sterically unhindered amines the amine nitrogen of at least one amino group is bonded only to primary carbon atoms and hydrogen atoms.

[0169] The sterically unhindered primary or secondary amine is, for example, selected from alkanolamines, such as monoethanolamine (MEA), diethanolamine (DEA), ethylaminoethanol, 1-amino-2-methylpropan-2-ol, 2-amino-1-butanol, 2-(2-aminoethoxy)ethanol and 2-(2-aminoethoxy)ethanamine,

[0170] polyamines, such as hexamethylenediamine, 1,4-diaminobutane, 1,3-diaminopropane, 3-(methylamino)propylamine (MAPA), N-(2-hydroxyethyl)ethylenediamine, 3(dimethylamino)propylamine (DMAPA), 3-(diethylamino)propylamine, N,N′-bis(2-hydroxyethyl)ethylenediamine,

[0171] 5-, 6- or 7-membered saturated heterocycles which have at least one NH group in the ring and may comprise one or two further heteroatoms selected from nitrogen and oxygen in the ring, such as piperazine, 2-methylpiperazine, N-methylpiperazine, N-ethylpiperazine, N-(2-hydroxyethyl)piperazine, N-(2-aminoethyl)piperazine, homopiperazine, piperidine and morpholine.

[0172] Particular preference is given to 5-, 6- or 7-membered saturated heterocycles which have at least one NH group in the ring and may comprise one or two further heteroatoms selected from nitrogen and oxygen in the ring. Very particular preference is given to piperazine.

[0173] In one embodiment the absorption medium comprises methyldiethanolamine and piperazine.

[0174] The molar ratio of activator to sterically hindered amine or tertiary amine is preferably in the range from 0.05 to 1.0, particularly preferably in the range from 0.05 to 0.7.

[0175] The absorption medium generally comprises 10% to 60% by weight of amine.

[0176] The absorption medium is preferably aqueous.

[0177] The absorption medium may further comprise a physical solvent. Suitable physical solvents are, for example, N-methylpyrrolidone, tetramethylenesulfone, methanol, oligoethylene glycol dialkyl ethers such as oligoethylene glycol methyl isopropyl ether (SEPASOLV MPE), oligoethylene glycol dimethyl ether (SELEXOL). The physical solvent is generally present in the absorption medium in amounts of 1% to 60% by weight, preferably 10% to 50% by weight, in particular 20% to 40% by weight.

[0178] In a preferred embodiment the absorption medium comprises less than 10% by weight, for example less than 5% by weight, in particular less than 2% by weight of inorganic basic salts, such as potassium carbonate for example.

[0179] The absorption medium may also comprise additives, such as corrosion inhibitors, antioxidants, enzymes etc. In general, the amount of such additives is in the range of about 0.01-3% by weight of the absorption medium.

[0180] Further examples of absorption mediums are (1-1) aqueous solution of methyldiethanolamine (MDEA) (2.2 M) and piperazine (1.5 M); (1-2) aqueous solution of 2-(2-tert-butylaminoethoxy)ethanol (TBAEE) (2.2 M) and piperazine (1.5 M); and (1-3) aqueous solution of 2-(2-tert-butylaminoethoxy)ethanol (TBAEE) (2.2 M) and monoethanolamine (MEA) (1.5 M). With the absorption mediums listed above acid gas removal of e.g. CO.sub.2, H.sub.2S, SO.sub.2, CS.sub.2, HCN, COS or mercaptans is possible. Other applications consider absorption of alcohols, acetone and/or organic acids in water, ethylene oxide in water, ammonia in water, water vapor in di- or triethylene glycol, hydrocarbons in high boiling organic solvents, HF, HCl, HBr, Hl in water, NOx in H2O/HNO3 or SO2 in alkaline solution.

[0181] According to FIG. 1, via the inlet 16, a suitably pretreated gaseous inlet stream comprising carbon dioxide (CO.sub.2) and/or hydrogen sulfide (H.sub.2S) is contacted in countercurrent, in an absorber 12, with regenerated absorption medium which is fed in the absorber 12 via the absorption medium line 18. The absorption medium removes carbon dioxide and/or hydrogen sulfide from the gas inlet stream by absorption. This results in a carbon dioxide- and/or hydrogen sulfide-depleted clean outlet gas via the offgas line 20.

[0182] Via the absorption medium line 22, the heat exchanger 24 in which the CO.sub.2- and/or H.sub.2S-laden absorption medium is heated up with the heat from the regenerated absorption medium conducted through the absorption medium line 28. Via the absorption medium line 42, the CO.sub.2- and/or H.sub.2S-laden absorption medium is fed to the desorption column 14 and regenerated. From the lower part of the desorption column 14, the absorption medium is conducted into the reboiler 30, where it is heated and partly evaporated. The mainly water-containing vapor is recycled into the desorption column 14, while the regenerated absorption medium is fed back to the absorber 12 via the absorption medium line 28, the heat exchanger 24, the absorption medium line 32, the cooler 34 and the absorption medium line 18. In the heat exchanger 24 the regenerated absorption medium heats up the CO.sub.2- and/or H.sub.2S-laden absorption medium and at the same time cools down itself.

[0183] Instead of the boiler 30 shown, it is also possible to use other heat exchanger types to raise the stripping vapor, such as a natural circulation evaporator, forced circulation evaporator or forced circulation flash evaporator. In the case of these evaporator types, a mixed-phase stream of the regenerated absorption medium and stripping vapor is returned to the bottom of the desorption column 14, where the phase separation between the vapor and the absorption medium takes place. The regenerated absorption medium to the heat exchanger 24 is either drawn off from the circulation stream from the bottom of the desorption column 14 to the evaporator or conducted via a separate line directly from the bottom of the desorption column 14 to the heat exchanger 24.

[0184] The CO.sub.2- and/or H.sub.2S-containing gas released in the desorption column 14 leaves the desorption column 14 via the offgas line 36. It is conducted into a condenser 38 with integrated phase separation, where it is separated from entrained absorption medium vapor. Subsequently, a liquid consisting mainly of water is conducted through the absorption medium line 40 into the upper region of the desorption column 14, and a CO.sub.2- and/or H.sub.2S-containing gas is discharged via the gas line 44.

[0185] The flowsheet of FIG. 1 illustrates a gas treatment plant 10 including gas treatment units 12, 14 and may be used as a basis to provide the gas treatment plant configuration parameters, which are provided as part of the process specific input parameters for performing the methods for determining operating and/or dimensioning parameters.

[0186] FIG. 2 shows a schematic flowchart diagram of the method 20 for determining operating and/or dimensioning parameters of a gas treatment plant 10 according to an example embodiment of the present invention.

[0187] The method 20 for determining operating and/or dimensioning parameters of a gas treatment plant 10 may comprise at least the following steps:

[0188] As a first step of the method 20, generating S1 a request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant 10 is performed. The request comprises process specific input parameters including absorber input parameters. The absorber input parameters include at least one of the absorber height or the solution flow rate as corresponding input parameter. Hence it may not be the absorber height that is specified, but rather the composition in the treated outlet stream. Similarly, it may not be flow rate that is specified, but rather the loading factor of the treatment solution in the absorber 12. In specifying relative parameters different scenarios exist. In one example the absorber input parameters may include the composition in the treated outlet stream and the loading factor of the treatment solution in the absorber 12. In another example the absorber input parameters may include the composition in the treated outlet stream and flow rate. In yet another example the absorber input parameters may include the absorber height and the loading factor of the treatment solution in the absorber 12.

[0189] In another embodiment the absorber input parameters further include the absorber diameter as relative parameter. In this embodiment at least one of the absorber height, the solution flow rate or the absorber diameter are provided as relative parameter. Here different scenarios are possible: [0190] only one parameter, namely the absorber height, the solution flow rate or the absorber diameter, is provided as relative parameter, [0191] two parameters are provided as relative parameters, e.g. the absorber height and the solution flow rate or the absorber height and the absorber diameter or the solution flow rate and the absorber diameter, or [0192] all three parameters, namely the absorber height, the solution flow rate and the absorber diameter, are provided as relative parameter.

[0193] The absorber input parameters may further include configuration parameters specifying the absorber's internal configuration. Such configuration parameters may further specify the column type such as packed bed or tray column, the number of segments indicating the height discretization in the column, pressure conditions like the pressure drop over the column, temperature conditions or a distributor type for the liquid treatment solution.

[0194] The process specific input parameters may further include inlet stream specific parameters such as the composition, the molar flow rate, temperature, pressure or the like, treatment solution parameters such as the composition, grade, strength or the like. If further gas treatment units such as a regenerator are present, the process specific input includes further parameters specifying each of the gas treatment units. Alternatively, some of the parameters specifying further gas treatment units may be pre-set to simplify and reduce the number of process specific input parameters to be provided.

[0195] The gas treatment plant 10 may include more than one absorber and/or further gas treatment units, as for instance shown in FIG. 1 with absorber 12, regenerator 14, cooler 34, heat exchanger 24, reboiler 30 and condenser 38. Preferably, the process specific input parameters include configuration parameters, which specify the gas treatment units included in the gas treatment plant 10 and their interconnection. These may be partly or fully pre-defined providing a fixed set of possible configurations. Such pre-defined configurations may be stored in a database and can be identified in the process specific input parameters via identifiers signifying the respective configurations. Pre-defined configurations simplify the design process for the user by reducing the number of viable options. Moreover, it leads to a more robust and stable determination of operating and/or dimensioning parameters, since non-sensible or technically meaningless specifications are excluded. Where the configurations are only partly or not pre-defined the method 20 can include a validation to ensure sensible configurations are provided. Such a validation for instance checks that all required gas treatment units are included, that all interconnections between the gas treatment units are present, that no fault interconnections between the gas treatment units are present or that the gas treatment units are interconnected in accordance with their function. Such validation may be implemented in a rule-based manner.

[0196] If the gas treatment plant 10 also includes a regenerator as for instance shown in FIG. 1, the process specific input parameters further comprise regenerator input parameters including at least one of the reboiler duty or the regenerator diameter as relative parameters. Hence for the reboiler duty it may not be the reboiler duty that is specified, but the fraction quality of the regenerated treatment solution or strip steam ratio. Similarly, for the regenerator diameter it may not be the regenerator diameter that is specified, but the acceptable hydraulic load. In specifying relative parameters different scenarios exist. In one example the regenerator input parameters may include the fraction quality of the regenerated treatment solution or strip steam ratio and the acceptable hydraulic load. In another example the regenerator input parameters may include the fraction quality of the regenerated treatment solution or strip steam ratio and the regenerator diameter. In yet another example the regenerator input parameters may include the reboiler duty and the acceptable hydraulic load.

[0197] In a further embodiment the regenerator input parameters include configuration parameters specifying the regenerator configuration. Such configuration parameters may further specify the regenerator column type such as packed bed or tray column, the number of segments in the column, pressure conditions like the pressure drop over the column or temperature conditions.

[0198] With the relative parameters available for the absorber input parameters and for the regenerator input parameters all combinations are possible. Depending on the user profile all or only a subset of options may be available to the user. The process specific input parameters may thus include all of the available absorber and regenerator input paraments in relative form. Alternatively only a sub-set of the available absorber and regenerator input paraments are provided in relative form.

[0199] As a second step of the method 20, transmitting S2 the generated request over a network may be performed. Here the requested generated at the input unit may be transmitted from the client device to the server via a wireless or wired network. On the server side, the request is received S3 in a third step. On receipt of the request, the validity of the request is checked S4. Here particularly, compliance with the object permissions for the process-specific parameters associated with the user profile are validated. If the request is not valid an error message or notification is transmitted S5 from the server to the client device.

[0200] If the request is valid, the digital model based on the process specific input parameters and the thermodynamic parameters is initialized S6. The digital model represents the gas treatment units of the gas treatment plant 10. The digital model includes models for each gas treatment unit of the gas treatment plant 10 such as an absorber model and a regenerator model. The model comprises thermodynamic equations indicative of the thermodynamic conditions such as the mass and energy transfer present in the respective gas treatment unit, which refers to the unit operations implemented in the gas treatment plant 10. The equations are combined in a single system of equations including all the equations for all gas treatment units present in the gas treatment plant 10. For each relative parameter specified in the process specific input parameters the system of equations includes further equations taking account of the relation between the relative parameter and the respective corresponding parameter. This allows to release the respective corresponding parameter and to leave it to the determination of the operating and/or dimensioning parameters.

[0201] Depending on the relative parameters provided via the process specific input parameters the digital model of the gas treatment plant is initialized S7 accordingly. For each relative parameter provided via the process specific input parameters the digital model includes a relation between the relative and the corresponding parameter to release the corresponding parameter in the equation-based solution method. In other words, for each relative parameter the system of equations will include an additional equation allowing to release the corresponding parameter.

[0202] In step S7 the request is processed based on the initialized digital model and operating and/or dimensioning parameters are calculated iteratively in an equation-based solution approach until convergence criteria are met. During such calculation status notifications may be transmitted from the server to the client device allowing the user to follow the progress of the calculation.

[0203] Lastly, the operating and/or dimensioning parameters resulting from such processing are transmitted S8 from the server to the client device.

[0204] FIG. 3 shows a schematic flowchart diagram of the method 30 for determining operating and/or dimensioning parameters of a gas treatment plant 10 according to a further example embodiment of the present invention.

[0205] In step S9 the request to initiate the determination of operating and/or dimensioning parameters of the gas treatment plant is received. The request comprises process specific input parameters including gas treatment unit input parameters. The gas treatment unit input parameters include at least one relative parameter which is independent of the plant throughput, wherein the relative parameter relates to at least one corresponding parameter dependent on the plant throughput. In a specific embodiment the request comprises process specific input parameters including absorber input parameters, wherein the absorber input parameters include a loading factor of the treatment solution in the absorber as relative parameter.

[0206] On receipt of the request, the validity of the request is checked S10. Here particularly, compliance with the object permissions of the process-specific parameters are validated. If the request is valid, thermodynamic parameters indicative of thermodynamic properties in the gas treatment plant 10 under operating conditions are provided S11. Such database access complements the input file and as such simplifies the design process. The thermodynamic parameters are indicative of thermodynamic properties in gas treatment units such as the absorber 12 under operating conditions. The data may be stored in a database unit and complements the process specific input parameters. Based on historical measurement data, e.g. as measured for gas treatment plants 10 in operation or in experimental set-ups, the thermodynamic parameters may provide a viable model base for e.g. thermodynamic absorption medium-gas parameters or kinetic parameters. Including such parameters based on historical measurement data increases the accuracy of the method and reduces the number of parameters to be provided via the process specific input parameters.

[0207] If the request is valid, the digital model based on the process specific input parameters and the thermodynamic parameters is initialized S12. The digital model represents the gas treatment units of the gas treatment plant 10. The digital model includes models for each gas treatment unit of the gas treatment plant 10 such as an absorber model and a regenerator model. The model comprises thermodynamic equations indicative of the thermodynamic conditions such as the mass and energy transfer present in the respective gas treatment unit, which refers to the unit operations implemented in the gas treatment plant 10. The equations are combined in a single system of equations including all the equations for all gas treatment units present in the gas treatment plant 10. For each relative parameter specified in the process specific input parameters the system of equations includes further equations taking account of the relation between the relative parameter and the respective corresponding parameter. This allows to release the respective corresponding parameter and to leave it to the determination of the operating and/or dimensioning parameters.

[0208] Depending on the relative parameters provided via the process specific input parameters the digital model of the gas treatment plant is initialized S12 accordingly. For each relative parameter provided via the process specific input parameters the digital model includes a relation between the relative and the corresponding parameter to release the corresponding parameter in the equation-based solution method. In other words, for each relative parameter the system of equations will include an additional equation allowing to release the corresponding parameter.

[0209] In step S13 operating and/or dimensioning parameters are calculated iteratively in an equation-based solution approach based on the initialized digital model. During such calculation status notifications may be transmitted from the server to the client device allowing the user to follow the progress of the calculation.

[0210] In step S14 the calculation of operating and/or dimensioning parameters is stopped, if convergence criteria are met. The convergence criteria relate to physical system balances. Examples for such balances are those provided by the MESH equations (Material balances, Equilibrium relations, Summation equations, Heat balances) or by the MERSHQ equations (Material balances, Energy balances, mass and heat-transfer Rate equations, Summation equations, Hydraulic equations for pressure drop, eQuilibrium equations) and optionally cost equations for e.g. operational and/or capital expenditures. Here convergence refers to iteratively determining dimensioning and/or operating parameters until convergence criteria are reached in the sense that a threshold value for the physical system balances is reached.

[0211] In step S15 the operating and/or dimensioning parameters according to the converged calculation are output. The operating and/or dimensioning parameters include depending on the relative input parameters the absorber height, the absorber diameter, the treatment solution flow rate, the reboiler duty and/or the regenerator diameter. The operating and/or dimensioning parameters include, if only a sub set of the available input parameters are provided as relative parameters, the corresponding sub-set of corresponding parameters.

[0212] FIG. 4 shows a schematic diagram of a system for determining operating and/or dimensioning parameters of a gas treatment plant 10 according to an example embodiment of the present invention.

[0213] The system 100 for determining operating and/or dimensioning parameters of a gas treatment plant 10 comprises a client device 110, a database server 120, and a determination server 130.

[0214] The client device 110 includes an input unit 110-1 that is configured to generate process specific input parameters. Such parameters may be provided by a user or pre-set but still editable by the user. The client device 110 sends the request to initiate the determination of operating and/or dimensioning parameters to the determination server 130. The request is send via a wired or wireless network such as a Local Area Networks (LAN) and includes the process specific input parameters.

[0215] On the receiver side the determination server 130 comprises the interface unit 130-1, the determination processing unit 130-2 and the output interface 130-4. The interface unit 130-1 is configured to receive the request initiating the determination of operating and/or dimensioning parameters. The data base server 120 comprising the database unit 120-1 is configured to provide thermodynamic parameters indicative of thermodynamic properties in the gas treatment plant 10 under operating conditions. The thermodynamic parameters may be based on historical measurement data.

[0216] The determination processing unit 130-2 is in communication with the database unit 120-1 and the interface unit 130-1 and is configured to initialize the digital model based on the process specific input parameters and the thermodynamic parameters. The determination processing unit 130-2 is further configured to determine operating and/or dimensioning parameters of the gas treatment plant 10 using the equation-based solution method for the digital model. Determining the such parameters is done iteratively until convergence criteria are reached and real-time status may be provided to the client device 110.

[0217] The output interface 130-4 is configured to output the operating and/or dimensioning parameters including corresponding parameters depending on the corresponding dimensionless input parameter as described above. The determined operating and/or dimensioning parameters received from the calculation unit 130-2 are send to the client device 110 via a wired or wireless network such as a Local Area Networks (LAN) from the output interface 130-4. On the client device 110 side a display unit 110-2 may output the result to a user or may act as an interface providing the result to further engineering devices.

[0218] FIG. 5 shows an example embodiment of a graphical user interface 200 to generate the process specific input parameters for the method.

[0219] For specification of equipment dimensions and process conditions the input unit 110-1 includes an input display 200. For guidance of the user the input display 200 provides process specific input parameters in groups 210. For example, process specific input parameters related to the inlet stream input parameters, the absorption medium input parameters, the gas treatment plant configuration parameters 220 or the gas treatment unit input parameters like the absorber input parameters 230 or the regenerator input parameters are grouped and displayed separately in accordance with the grouping.

[0220] The grouping of such parameters may further have a hierarchical structure with each group being assigned a dependency or hierarchy level. The dependency or hierarchy level may determine which group on the upper hierarchy level has to be filled with data, e.g. in the sense of providing respective process specific input parameters, as a pre-condition to unlock the next lower hierarchy level. Here unlocking includes the respective group of parameters being activated for input, e.g. via the input mask 240 that becomes visible on a display or input fields that become editable. As for instance shown in FIG. 5, the group relating to the absorber input parameters 230 are unlocked only when the group of gas treatment plant configuration parameters 220 is filled with respective data. In FIG. 5 the group relating to the gas treatment unit input parameters is labelled units including the sub-groups absorber 230, flash, regenerator and heat exchangers. Such a grouping with hierarchical structure on the input unit 110-1 side provides user guidance and avoids errors in providing the process specific input parameters.

[0221] For further guidance meaningful parameters which have a direct physical connection on one design value may be grouped and displayed in a selectable format such as a drop-down list or as shown in FIG. 5 via a selectable box. For example, in case of the absorber input parameter the input mask 240 includes the solution flow rate specification 280 that can be defined by a value for the mass or volume flow rate or preferably by the loading factor.

[0222] With this structure the user input unit 110-1 gives guidance to the user in the design phase of a gas treatment plant design to specify only physically meaningful parameters, which have a direct impact on the process values. Due to the grouping of specifications in the input, the method is very easy to use. Applying the method to create a gas treatment plant design the designer will specify a set of physically meaningful input parameters so that the result gives already the desired result after one step of user input, which reduces the required time for the design procedure significantly.

[0223] As example, a preferred set of standard specifications of the absorber 12 referenced to as dimensionless specifications could be [0224] to specify 270 the concentration of CO.sub.2 or H.sub.2S in the treated gas to calculate the absorber height, [0225] to specify 250 the acceptable hydraulic load (distance to hydraulic flooding conditions or safety factor) to calculate the absorber diameter and [0226] to specify 280 the maximum CO.sub.2/H.sub.2S loading factor or maximum combined CO.sub.2+H.sub.2S loading factor to calculate the solution flow rate.

[0227] Additionally the solution temperature, the temperature difference between absorber inlet and outlet or the transferred heat in the absorber may be specified 260. For the regeneration the required quality of the key component in the regenerator or stipper bottom stream or lean solution to calculate the reboiler duty can be specified in the input mask 240 which belongs to the group of regenerator input parameters.

[0228] The method uses an equation-oriented solution approach, which allows this approach of dimensionless specifications. One example of the dimensionless specifications is the implementation to release the column height. Thus, the absorber height can be calculated as result of another connected specifications like the acid gas content in the treated gas.

[0229] FIG. 6 illustrates an example embodiment for determining the CO.sub.2 loading factor via the ratio of the actual loading to the equilibrium loading in the liquid phase.

[0230] One element for allowing the relative parameters is to provide the loading factor at the absorber bottom or the maximum loading factor along the absorber height. Example column profiles to determine the loading factor are shown in FIG. 6. The first graphical representation of absorber height versus temperature illustrates the temperature profiles in the gas and liquid phase. Providing the loading factor profile is especially important for absorption processes with a pronounced temperature bulge as shown in the first graphical representation. Such temperature bulge occurs when exothermic heat of reaction and/or heat of absorption is released. The second graphical representation of absorber height versus CO.sub.2 concentration illustrates the CO.sub.2 concentration profile in the gas phase.

[0231] Temperature and CO.sub.2 concentration in the gas phase determine the equilibrium loading profile of CO.sub.2 in the liquid phase as shown by the dashed line in the third graphical representation of absorber height versus CO.sub.2 loading. The actual loading profile of CO.sub.2 in the liquid phase as shown by the solid line is determined in for each iteration of the equation-based solution method. The loading factor profile as shown in the fourth graphical representation is defined by the actual loading of CO.sub.2 in the liquid phase divided by the equilibrium loading.

[0232] A value of 1 for the loading factor means that the equilibrium value is reached and no mass transfer occurs. This will lead to an infinite absorber height as calculation result for specifying a CO.sub.2 concentration in the treated outlet gas. As consequence, for designing gas treatment plants the loading factor needs to be specified to a value <1 to avoid a physically not possible specification. A reasonable loading factor is for instance <0.95 or <0.9.

[0233] If CO.sub.2 and H.sub.2S both are present in the inlet gas the single loading factors of CO.sub.2 or H.sub.2S may be misleading and may not be useful for specification. For such cases, a combined loading factor for CO.sub.2+H.sub.2S is used as specification.

[0234] In the example FIG. 6 of the loading factor profile along the absorber it can be observed that the maximum value of the loading factor is reached at the absorber top. This is due to specification of the CO.sub.2 content in the treated gas at 90% of the absorber height and the available lean loading at the absorber top. This maximum loading factor at the absorber top is acceptable and does not lead to physically unreasonable conditions. However, the maximum loading factor around the position of the maximum temperature is critical and needs to be limited to values <1 as mentioned above. To ensure, that the maximum loading factor is specified at the right position, the loading factor is evaluated from absorber bottom to a defined absorber height fraction.

[0235] FIGS. 7 to 9 illustrate the liquid phase temperature behavior, the gas phase CO.sub.2 content behavior and the loading factor as determined for different liquid flow rates in %. These illustrations resemble the behavior in the absorber of the gas treatment plant, if the liquid flow rate as parameter dependent on the plant throughput, is varied. Notably, the profiles in FIGS. 7 and 8 show a large effect in the profile shape for flow rates between 110% and 98%. Correspondingly, the concentration profile in FIG. 8. and the loading factor profile in FIG. 9 show that CO.sub.2 breakthrough occurs around 98% at the absorber top. Below and above the flow rate of 100% the profile shape does not change significantly. Hence around the flow rate of 100% the profile shapes are the most sensitive.

[0236] This behavior of the physical quantities in the absorber—temperature and CO.sub.2 content in the gas—is reflected in the number of iterations shown in FIG. 10 when stepwise increasing the flow rate for the given values. In the region between 96 to 98% flow rate the convergence behavior is such that the determination of operating and/or dimensioning parameters takes up to 6 times more iterations than above or below that region. For the operation of the absorber in the gas treatment plant this signifies an instable operation mode, since the absorber would be operated close to the CO.sub.2 gas breakthrough point. Hence, in setting the flow rate to an adequate value signifying a stable absorber operation is crucial to design a correspondingly stable gas treatment plant. In order to ensure that such a stable solution is provided in determining the operating and/or dimensioning parameters, it is highly advantageous to allow the loading factor as an input. Depending on whether the loading factor is determined at the absorber bottom or the maximum is taken along the absorber height, the two regimes where fast convergence is possible can be distinguished. At the same time such an approach ensures that the determination results in operating and/or dimensioning parameters that allow stable operation of the absorber and the gas treatment plant.

[0237] The following example illustrates the significant efficiency increase to a user for designing a gas treatment plant and the simplification of the design procedure. Given are the conditions of two different inlet gases referred to as Case A and Case B, which only differ in the concentration of carbon dioxide and methane. All other conditions like temperature, pressure flow rate and the concentration of residual components are identical. An overview of all inlet gas conditions is given in the following table:

TABLE-US-00001 Feed gas conditions Unit Case A Case B Flow rate Nm3/hr 500000 500000 Temperature ° C. 30 30 Pressure bar(a) 60 60 Composition in mole fraction Carbon dioxide (CO.sub.2) mole/mole 0.5 10 Methane (CH.sub.4) mole/mole 93.5 84 Ethane (C.sub.2H.sub.6) mole/mole 3 3 Propane (C.sub.3H.sub.8) mole/mole 2 2 Butane (C.sub.4H.sub.10) mole/mole 1 1 Water content — saturated saturated

[0238] The task is to design a grassroots CO.sub.2 removal plant for a LNG production plant with a CO.sub.2 concentration in the treated gas of 50 mole-ppm. The plant configuration should consist of an absorption column, an HP flash and a regenerator column. The user needs to define several process parameters like solution flow rate, absorber height, absorber diameter, reboiler duty, and regenerator diameter. Applying a state of the art process flow sheet simulator, plant geometry, conditions of inlet streams and process conditions need to be defined prior to running the simulation. The conditions of all outlet streams, like the CO.sub.2 concentration in the treated gas, are a result of the calculation of the process simulator. For achieving a specified acid gas concentration in the treated gas, the user needs to change process conditions mentioned above in a lot of manual iterations until the required CO.sub.2 concentration in the treated gas is reached. Reason is that even an experienced user a priori does not know the exact result for the operating and dimensioning parameters. Furthermore, the user may even define conditions during the manual iterations, which cannot lead to the required CO.sub.2 concentration in the treated gas. As example, the required CO.sub.2 concentration in the treated gas can only be reached, if the CO.sub.2 concentration in the lean solution is below the corresponding CO.sub.2 equilibrium concentration at the absorber top. Such conditions need to be identified by the user, which requires additional manual iterations. In this example, the user needs to define not only but at least the five main process parameters solution flow rate, absorber height, absorber diameter, reboiler duty and regenerator diameter. The following table shows results for these five process parameters as relative values between the example cases A and B.

TABLE-US-00002 Main process parameters Case A Case B Solution flow rate P1 16.35 * P1  Absorber packing height P2 0.80 * P2 Absorber diameter P3 1.55 * P3 Reboiler duty P4 19.22 * P4  Regenerator diameter P5 4.47 * P5

[0239] Applying a state of the art process flow sheet simulator, the user requires a lot of manual iterations for the design of a CO.sub.2 removal plant for Case A. Although knowing the result of Case A, Case B leads to very different conditions, which are not obvious to the user a priory. Thus, the user again requires a lot of manual iterations for the design of a CO.sub.2 removal plant for Case B. These examples show, that application of a state of the art process simulator leads to a lot of manual and time-consuming iteration steps, which make the design process very tedious and inefficient.

[0240] Applying the present invention for the example cases A and B and specifying the five parameters CO.sub.2 concentration in the treated gas, maximum loading factor for CO.sub.2 in the absorber, safety factor for the absorber, loading factor for CO.sub.2 at the absorber top and safety factor for the regenerator, the user will receive the results shown in the table above in one step of manual input. This leads to a significant simplification of the design procedure and to a reduced time for the design procedure and thus to increased efficiency.

[0241] Any of the components described herein used for implementing the methods described herein may be in a form of a computer system having one or more processing devices capable of executing computer instructions. The computer system may be communicatively coupled (e.g., networked) to other machines in a local area network, an intranet, an extranet, or the Internet. The computer system may operate in the capacity of a server or a client machine in client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The computer system may be a PC (Personal Computer), a tablet PC, a PDA (Personal Digital Assistant), a cellular telephone, a web appliance, a server, a network router, switch or bridge, or any machine capable of executing a set of instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, it is to be understood that the terms “computer system,” “machine,” “electronic circuitry,” and the like are not necessarily limited to a single component, and shall be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein.

[0242] Some or all of the components of such a computer system may be utilized by or illustrative of any of the components of the system 100, such as the client device 110, the database 120, and the determination server 130. In some embodiments, one or more of these components may be distributed among multiple devices, or may be consolidated into fewer devices than illustrated. The computer system may include, for example, one or more processing devices, a main memory (e.g., ROM, flash memory, DRAM (Dynamic Random Access Memory) such as SDRAM (Synchronous DRAM) or RDRAM (Rambus DRAM), etc.), a static memory (e.g., flash memory, SRAM (Static Random Access Memory), etc.), and/or a data storage device, which communicate with each other via a bus.

[0243] A processing device may be a general-purpose processing device such as a microprocessor, microcontroller, central processing unit, or the like. More particularly, the processing device may be a CISC (Complex Instruction Set Computing) microprocessor, RISC (Reduced Instruction Set Computing) microprocessor, VLIW (Very Long Instruction Word) microprocessor, or a processor implementing other instruction sets or processors implementing a combination of instruction sets. The processing device may also be one or more special-purpose processing devices such as an ASIC (Application-Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), a CPLD (Complex Programmable Logic Device), a DSP (Digital Signal Processor), a network processor, or the like. The methods, systems and devices described herein may be implemented as software in a DSP, in a micro-controller, or in any other side-processor or as hardware circuit within an ASIC, CPLD, or FPGA. It is to be understood that the term “processing device” may also refer to one or more processing devices, such as a distributed system of processing devices located across multiple computer systems (e.g., cloud computing), and is not limited to a single device unless otherwise specified.

[0244] The computer system may further include a network interface device. The computer system also may include a video display unit (e.g., an LCD (Liquid Crystal Display), a CRT (Cathode Ray Tube) display, or a touch screen), an alphanumeric input device (e.g., a keyboard), a cursor control device (e.g., a mouse), and/or a signal generation device (e.g., a speaker).

[0245] A suitable data storage device may include a computer-readable storage medium on which is stored one or more sets of instructions (e.g., software) embodying any one or more of the methodologies or functions described herein. The instructions may also reside, completely or at least partially, within the main memory and/or within the processor during execution thereof by the computer system, main memory, and processing device, which may constitute computer-readable storage media. The instructions may further be transmitted or received over a network via a network interface device.

[0246] A computer program for implementing one or more of the embodiments described herein may be stored and/or distributed on a suitable medium, such as an optical storage medium or a solid state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the internet or other wired or wireless telecommunication systems. However, the computer program may also be presented over a network like the World Wide Web and can be downloaded into the working memory of a data processor from such a network.

[0247] According to a further example embodiment of the present invention, a data carrier or a data storage medium for making a computer program element available for downloading is provided, which computer program element is arranged to perform a method according to one of the previously described embodiments of the invention.

[0248] The terms “computer-readable storage medium,” “machine-readable storage medium,” and the like should be taken to include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) that store the one or more sets of instructions. The terms “computer-readable storage medium,” “machine-readable storage medium,” and the like shall also be taken to include any transitory or non-transitory medium that is capable of storing, encoding or carrying a set of instructions for execution by the machine and that cause the machine to perform any one or more of the methodologies of the present disclosure. The term “computer-readable storage medium” shall accordingly be taken to include, but not be limited to, solid-state memories, optical media, and magnetic media.

[0249] Some portions of the detailed description may have been presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is herein, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.

[0250] It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the preceding discussion, it is appreciated that throughout the description, discussions utilizing terms such as “receiving,” “retrieving,” “transmitting,” “computing,” “generating,” “adding,” “subtracting,” “multiplying,” “dividing,” “selecting,” “optimizing,” “calibrating,” “detecting,” “storing,” “performing,” “analyzing,” “determining,” “enabling,” “identifying,” “modifying,” “transforming,” “applying,” “extracting,” and the like, refer to the actions and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (e.g., electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.

[0251] It has to be noted that embodiments of the invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims whereas other embodiments are described with reference to the device type claims.

[0252] However, a person skilled in the art will gather from the above and the following description that, unless otherwise notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters is considered to be disclosed with this application. However, all features can be combined providing synergetic effects that are more than the simple summation of the features.

[0253] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or example and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art and practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In some instances, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring the present disclosure.

[0254] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or controller or other unit may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.