Sulfur Recovery/ Tailgas Cleanup

ProMax contains a complete reactor suite that allows simulation of various sulfur recovery and tail gas cleanup plants.

Claus sulfur recovery
Selectox/Recycle Selectox^®
COPETM
Ultra^®
Sulfreen^®
SCOT^®
SUPERCLAUS^®
MODOP^®
CBA^®

There are a number of Claus sulfur recovery unit configurations available. For example, acid gas bypass, hot gas bypass, enhanced oxygen, catalytic burners and more.

Benefits

Directly link the amine, sulfur and tailgas units all in one project
Optimize plant performance through custom solver routines
Automatically determine overall plant sulfur recovery
Easily determine the sulfur dewpoint
Calculate steam generation and consumption quantities
Integrate the complete steam system into the simulation

Gibbs Reaction Set Applications

ProMax uses predefined Gibbs reaction sets to make it very easy for the user to model the plant. Simply select the reactor type from a drop down list and the appropriate components for that reaction will automatically be selected for inclusion across the reactor. Some of the predefined reaction sets are listed below.

General - This can be used to model any type of reactor in a sulfur recovery unit. No constraints are set by default, and all components are Gibbs Reactive (i.e. all components are included in the reaction).

Acid Gas Burner - This Gibbs Set has default settings used to model the burner at the inlet of a Claus sulfur recovery unit. All Components are included by default. Default Constraints are selected to predict CS₂ and COS formation in the burner.

Burner - This can be used to model any type of reactor in a sulfur recovery unit. No constraints are set by default, and all components are Gibbs Reactive (i.e. all components are included in the reaction). This model could be used to model an incinerator or Reducing Gas Generator (RGG).

Claus Bed - This Gibbs Set has default settings used to model standard Claus beds. There are no default constraints. Use the Bypass Fraction parameter to effectively set an "equilibrium conversion". This type Gibbs Set is not intended to model the first Claus bed since the first Claus bed temperature and catalyst type should be such that COS and CS2 are destroyed.

Sulfur Direct Oxidation - This Gibbs set has default settings intended to model a Selectox type reactor or "catalyst burner" which can replace the conventional burner for cases with very low H₂S. This type reactor is also sometimes used for tail gas applications. There are no default constraints.

Sulfur Partial Oxidation - This Gibbs Set has default settings intended to model the SUPERCLAUS type direct oxidation bed at the end of the Claus unit. There are no default constraints.

Hydrolyzing Claus Bed - The default settings for this Gibbs set are intended to model the first Claus bed where the temperature and catalyst type are typically such that COS and CS₂ are destroyed.

Sub-Dewpoint Claus Bed - This type Claus bed operates below the sulfur dew point. This Gibbs Set has default settings used to model the 2nd and subsequent Claus beds. There are no default constraints. This Gibbs Set is typically used with the Single Inlet - Vapor and Liquid Outlet type of Reactor.

Sulfur Condenser - This type of reactor condenses sulfur species from the vapor to produce a liquid sulfur product.

Sulfur Hydrogenation - The default settings for this Gibbs Set are intended to model the Tail Gas Cleanup Unit (TGCU) Hydrogenation reactor in which all sulfur species are converted to H₂ S. The TGCU Hydrogenation reactor is normally used in conjunction with a Reducing Gas Generator (RGG) Reactor for the tail gas. Hydrocarbons and ammonia are the only non-reactive components by default.

Sulfur Redistribution - The default settings for this Gibbs Set are used to model the 2nd pass of the waste heat boiler from about 1200°F to 600°F (650°C to 315°C) where the redistribution of sulfur species is the primary reaction. There are no default constraints.

Sulfur Thermal Reaction Zone - The default settings for this Gibbs Set are intended to model the 1st pass of the waster heat boiler from the burner flame temperature down to about 1200°F (650°C).

COS and CS₂ Formation and Destruction

COS and CS₂ are formed in the acid gas burner, and are partially destroyed in the first Claus bed provided the appropriate catalyst is present and the temperature is sufficiently high.

Equilibrium models do not adequately predict the formation of COS and/or CS₂ in the burner as observed concentrations can be significantly higher than equilibrium predictions. A number of semi-empirical correlations have been developed to more accurately predict COS and CS₂ formation in the burner:

Fischer 1974 - This correlation predicts the concentration of COS, CS₂ out of the burner. Reference: Fischer, H., "Burner/Fire Box Design Improves Sulfur Recovery," Hydrocarbon Processing, October, 1974, pp. 125-129.

Luinstra d'Haene 1989 - This correlation predicts the concentration of CS₂ out of the burner and requires a residence time specification. Reference: Luinstra, E. A., and P. E. d'Haene, "Catalyst Added to Claus Furnace Reduces Sulfur Losses," Hydrocarbon Processing, July, 1989, pp. 53-57.

NSERC 1993 - This correlation predicts the concentration of COS, CS₂ out of the burner. Reference: Monnery, W. D., W. Y. Svrcek, and L. A. Behie, “Modelling the Modified Claus Process Reaction Furnace and the Implications on Plant Design and Recovery,” Proceedings of the 43rd Laurance Reid Gas Conditioning Conference, Norman, Oklahoma,1993, pp. 261-309.

NSERC 2002 - This correlation predicts the concentration of CS₂. Pollock, A. E., P. D. Clark, N. I . Dowling, M. Huang, W. D. Monnery, and W. Y. Svrcek, “Finally – A Kinetic Model of the Modified Claus Process Reaction Furnace,” Proceedings of the 52nd Laurance Reid Gas Conditioning Conference, Norman, Oklahoma, 2002, pp. 43-62.
Pollock, A. E., "Kinetic Modelling of the Modified Claus Reaction Furnace," Ph.D. Dissertation, The University of Calgary, Calgary, Alberta, Canada, 2001. out of the burner.

Additional Reactor Options

TGCU Hydrogenation Reactor

The TGCU reactor converts all sulfur species to H₂S and it also requires reducing gas containing H₂ usually provided by a RGG (Reducing Gas Generator). This type of reactor is used in the tail gas when the TGCU is a MDEA unit.

Reducing Gas Generator (RGG)

The RGG provides H₂ for conversion of all sulfur species to H₂S in the TGCU Hydrogenation Reactor.

Sulfur Direct Oxidation Reactor

The SUPERCLAUS type reactors convert almost all the H₂S directly to Sulfur and are usually the final bed in a Claus unit. The traditional 2:1 H₂S to SO₂ ratio is not used. Instead 1% H₂S in the tail gas is the target.

Sulfur Catalytic Burner (Direct Oxidation)

This is a Selectox type reactor which acts as a "catalytic burner" to convert H₂S to elemental sulfur. Selective oxidation of H₂S to SO₂ occurs in the upper portion of the catalyst bed, and the Claus reaction occurs in the remainder of the bed. It is used for low H₂S cases, especially when the H₂S is so low that acid gas bypass around the burner would be insufficient to achieve an 1800F burner temperature. This reactor replaces the conventional burner. The Selectox can also be used in tail gas applications.

Tail Gas Incinerator

The incinerator operates at a minimum of 1500F. In addition to air, fuel gas is usually added to maintain the temperature. It is modeled as an adiabatic reactor with all components enabled and no constraints.


		Powerful Process Simulation Technology ProMax^® Unparalleled Customer Service


Free SixxacMenu module license Capabilities Amine Sweetening Glycol Dehydration Heat Exchanger Rating Crude Oil Refining LPG Recovery NGL Fractionation Caustic Treating Sulfur and TGCU Reactors Sour Water Stripper Pipelines Vessel Sizing Other Processes Interface Flowsheet Drawing Multiple Flowsheets Project Viewer Reporting Property Packages Extensibility TSWEET PROSIM Client List Sales Information Testimonials Announcements	Sulfur Recovery/ Tailgas Cleanup ProMax contains a complete reactor suite that allows simulation of various sulfur recovery and tail gas cleanup plants. Claus sulfur recovery Selectox/Recycle Selectox^® COPETM Ultra^® Sulfreen^® SCOT^® SUPERCLAUS^® MODOP^® CBA^® There are a number of Claus sulfur recovery unit configurations available. For example, acid gas bypass, hot gas bypass, enhanced oxygen, catalytic burners and more. Benefits Directly link the amine, sulfur and tailgas units all in one project Optimize plant performance through custom solver routines Automatically determine overall plant sulfur recovery Easily determine the sulfur dewpoint Calculate steam generation and consumption quantities Integrate the complete steam system into the simulation Gibbs Reaction Set Applications ProMax uses predefined Gibbs reaction sets to make it very easy for the user to model the plant. Simply select the reactor type from a drop down list and the appropriate components for that reaction will automatically be selected for inclusion across the reactor. Some of the predefined reaction sets are listed below. General - This can be used to model any type of reactor in a sulfur recovery unit. No constraints are set by default, and all components are Gibbs Reactive (i.e. all components are included in the reaction). Acid Gas Burner - This Gibbs Set has default settings used to model the burner at the inlet of a Claus sulfur recovery unit. All Components are included by default. Default Constraints are selected to predict CS₂ and COS formation in the burner. Burner - This can be used to model any type of reactor in a sulfur recovery unit. No constraints are set by default, and all components are Gibbs Reactive (i.e. all components are included in the reaction). This model could be used to model an incinerator or Reducing Gas Generator (RGG). Claus Bed - This Gibbs Set has default settings used to model standard Claus beds. There are no default constraints. Use the Bypass Fraction parameter to effectively set an "equilibrium conversion". This type Gibbs Set is not intended to model the first Claus bed since the first Claus bed temperature and catalyst type should be such that COS and CS2 are destroyed. Sulfur Direct Oxidation - This Gibbs set has default settings intended to model a Selectox type reactor or "catalyst burner" which can replace the conventional burner for cases with very low H₂S. This type reactor is also sometimes used for tail gas applications. There are no default constraints. Sulfur Partial Oxidation - This Gibbs Set has default settings intended to model the SUPERCLAUS type direct oxidation bed at the end of the Claus unit. There are no default constraints. Hydrolyzing Claus Bed - The default settings for this Gibbs set are intended to model the first Claus bed where the temperature and catalyst type are typically such that COS and CS₂ are destroyed. Sub-Dewpoint Claus Bed - This type Claus bed operates below the sulfur dew point. This Gibbs Set has default settings used to model the 2nd and subsequent Claus beds. There are no default constraints. This Gibbs Set is typically used with the Single Inlet - Vapor and Liquid Outlet type of Reactor. Sulfur Condenser - This type of reactor condenses sulfur species from the vapor to produce a liquid sulfur product. Sulfur Hydrogenation - The default settings for this Gibbs Set are intended to model the Tail Gas Cleanup Unit (TGCU) Hydrogenation reactor in which all sulfur species are converted to H₂ S. The TGCU Hydrogenation reactor is normally used in conjunction with a Reducing Gas Generator (RGG) Reactor for the tail gas. Hydrocarbons and ammonia are the only non-reactive components by default. Sulfur Redistribution - The default settings for this Gibbs Set are used to model the 2nd pass of the waste heat boiler from about 1200°F to 600°F (650°C to 315°C) where the redistribution of sulfur species is the primary reaction. There are no default constraints. Sulfur Thermal Reaction Zone - The default settings for this Gibbs Set are intended to model the 1st pass of the waster heat boiler from the burner flame temperature down to about 1200°F (650°C). COS and CS₂ Formation and Destruction COS and CS₂ are formed in the acid gas burner, and are partially destroyed in the first Claus bed provided the appropriate catalyst is present and the temperature is sufficiently high. Equilibrium models do not adequately predict the formation of COS and/or CS₂ in the burner as observed concentrations can be significantly higher than equilibrium predictions. A number of semi-empirical correlations have been developed to more accurately predict COS and CS₂ formation in the burner: Fischer 1974 - This correlation predicts the concentration of COS, CS₂ out of the burner. Reference: Fischer, H., "Burner/Fire Box Design Improves Sulfur Recovery," Hydrocarbon Processing, October, 1974, pp. 125-129. Luinstra d'Haene 1989 - This correlation predicts the concentration of CS₂ out of the burner and requires a residence time specification. Reference: Luinstra, E. A., and P. E. d'Haene, "Catalyst Added to Claus Furnace Reduces Sulfur Losses," Hydrocarbon Processing, July, 1989, pp. 53-57. NSERC 1993 - This correlation predicts the concentration of COS, CS₂ out of the burner. Reference: Monnery, W. D., W. Y. Svrcek, and L. A. Behie, “Modelling the Modified Claus Process Reaction Furnace and the Implications on Plant Design and Recovery,” Proceedings of the 43rd Laurance Reid Gas Conditioning Conference, Norman, Oklahoma,1993, pp. 261-309. NSERC 2002 - This correlation predicts the concentration of CS₂. Pollock, A. E., P. D. Clark, N. I . Dowling, M. Huang, W. D. Monnery, and W. Y. Svrcek, “Finally – A Kinetic Model of the Modified Claus Process Reaction Furnace,” Proceedings of the 52nd Laurance Reid Gas Conditioning Conference, Norman, Oklahoma, 2002, pp. 43-62. Pollock, A. E., "Kinetic Modelling of the Modified Claus Reaction Furnace," Ph.D. Dissertation, The University of Calgary, Calgary, Alberta, Canada, 2001. out of the burner. Additional Reactor Options TGCU Hydrogenation Reactor The TGCU reactor converts all sulfur species to H₂S and it also requires reducing gas containing H₂ usually provided by a RGG (Reducing Gas Generator). This type of reactor is used in the tail gas when the TGCU is a MDEA unit. Reducing Gas Generator (RGG) The RGG provides H₂ for conversion of all sulfur species to H₂S in the TGCU Hydrogenation Reactor. Sulfur Direct Oxidation Reactor The SUPERCLAUS type reactors convert almost all the H₂S directly to Sulfur and are usually the final bed in a Claus unit. The traditional 2:1 H₂S to SO₂ ratio is not used. Instead 1% H₂S in the tail gas is the target. Sulfur Catalytic Burner (Direct Oxidation) This is a Selectox type reactor which acts as a "catalytic burner" to convert H₂S to elemental sulfur. Selective oxidation of H₂S to SO₂ occurs in the upper portion of the catalyst bed, and the Claus reaction occurs in the remainder of the bed. It is used for low H₂S cases, especially when the H₂S is so low that acid gas bypass around the burner would be insufficient to achieve an 1800F burner temperature. This reactor replaces the conventional burner. The Selectox can also be used in tail gas applications. Tail Gas Incinerator The incinerator operates at a minimum of 1500F. In addition to air, fuel gas is usually added to maintain the temperature. It is modeled as an adiabatic reactor with all components enabled and no constraints.