Periodic Reporting for period 2 - GEOPRO (Accurate Geofluid Properties as key to Geothermal Process Optimisation)
Reporting period: 2021-05-01 to 2023-10-31
The GEOPRO project aims to generate targeted advances in the understanding and modelling of geofluid characteristics. The user objectives of the project include supporting geothermal users by:
• Supporting improved design efficiency – knowledge-based design of wellbore, pipework, heat exchangers for optimal conversion of the primary energy into electrical power;
• Enabling knowledge-based design activities for best control of the constraining fluid phenomena (such as scale formation, outgassing, and cavitation during changes in temperature and pressure), maximising uptime and operational effectiveness of the plant;
• Providing underpinning knowledge for the future exploration and exploitation of supercritical systems through improved “vectors to ore” arising from the ability to better use fluid chemistry to predict deep subterranean conditions.
As such, the project will work towards improving the a) accuracy and consistency of key thermodynamic and kinetic input data, and b) accuracy of the respective Equations of state (EoS) to develop a set of robust, user-friendly tools that would help to optimise sustainable reservoir management, power and heat production and reinjection strategies.
• Supporting improved design efficiency – knowledge-based design of wellbore, pipework, heat exchangers for optimal conversion of the primary energy into electrical power;
• Enabling knowledge-based design activities for best control of the constraining fluid phenomena (such as scale formation, outgassing, and cavitation during changes in temperature and pressure), maximising uptime and operational effectiveness of the plant;
• Providing underpinning knowledge for the future exploration and exploitation of supercritical systems through improved “vectors to ore” arising from the ability to better use fluid chemistry to predict deep subterranean conditions.
As such, the project will work towards improving the a) accuracy and consistency of key thermodynamic and kinetic input data, and b) accuracy of the respective Equations of state (EoS) to develop a set of robust, user-friendly tools that would help to optimise sustainable reservoir management, power and heat production and reinjection strategies.
In the reporting period the following activities have taken place:
• Report on relevant information on gap and priority analysis for geochemical datasets and equations of state (EoS).
• Design and development of a multi-phase flow loop for geothermal fluids
• Improvements and enhancements of the Flowphys1D flow assurance software, followed by building of models and performing flow assurance simulations for GEOPRO geothermal sites
In the final reporting period, the project has achieved the following results:
• Completed a review of current gaps in literature for datasets for different brine compositions;
• Experimental measurements to determine densities and volumes of different brines including specific heat capacities, enthalpies and solubilities.
• Developed models based to allow accurate prediction for complex solutions of CO2 and multicomponent mineral salts. to this end, Two types of models were used to test the densities of the experimental brines.
• Performed experiments to determine the solubility of important minerals (salts, sulphates, carbonates and oxides) for an insight into behaviour of solute in superheated and supercritical water
• Reviewed existing semi-empirical thermodynamic models / equations of state for aqueous solutes to supercritical conditions and development of new ones for application under superhot geothermal conditions.
• Evaluated reaction kinetics for mineral precipitation in superheated and supercritical water.
• Verified on user sites Insheim, Zorlu and IDDP3 to evaluate their fluid related problems via use of thermodynamic models. The main achievements towards the project objectives are as follows:
Zorlu case study:
Was centred on two operational problems relating to poor knowledge of physicochemical properties of very CO2-rich geothermal brines and carbonate scaling in surface pipelines and during re-injection.
To eliminate the lack of knowledge about the properties of the geothermal fluid, chemical composition, isotope chemistry and scale chemistry analysis were conducted for the solid, liquid, and gas forms of the geothermal fluid.
Optimizations were made for pipeline and inhibitor dosing inlcuding measurement on the scale thickness
Degassing pressures and well depths of non-condensable gases which are mainly composed of CO2 were found with the help of modelling studies
Inshiem case study:
Development of a joint thermodynamic modelling-field observation methodology and bringing new insights on three operational questions:
Gas Breakout Pressure (= Bubble point) on different operational conditions for the Insheim case study.
Pressure control for gas management.
Micro-degassing and corrosion processes correlation.
IDDP case study:
Scenario modelling for well siting of IDDP-3, including the first ever simulations that combined an existing reservoir model with explicitly represented magmatic heat sources
High quality models and simulations of utilization scenarios for both direct production and deep injection
Development and modelling of novel geochemical “pathfinders” to detect input of superhot fluids into the overlying, exploited conventional high-enthalpy reservoir by analyzing conventional fluid sampled from this.
• Report on relevant information on gap and priority analysis for geochemical datasets and equations of state (EoS).
• Design and development of a multi-phase flow loop for geothermal fluids
• Improvements and enhancements of the Flowphys1D flow assurance software, followed by building of models and performing flow assurance simulations for GEOPRO geothermal sites
In the final reporting period, the project has achieved the following results:
• Completed a review of current gaps in literature for datasets for different brine compositions;
• Experimental measurements to determine densities and volumes of different brines including specific heat capacities, enthalpies and solubilities.
• Developed models based to allow accurate prediction for complex solutions of CO2 and multicomponent mineral salts. to this end, Two types of models were used to test the densities of the experimental brines.
• Performed experiments to determine the solubility of important minerals (salts, sulphates, carbonates and oxides) for an insight into behaviour of solute in superheated and supercritical water
• Reviewed existing semi-empirical thermodynamic models / equations of state for aqueous solutes to supercritical conditions and development of new ones for application under superhot geothermal conditions.
• Evaluated reaction kinetics for mineral precipitation in superheated and supercritical water.
• Verified on user sites Insheim, Zorlu and IDDP3 to evaluate their fluid related problems via use of thermodynamic models. The main achievements towards the project objectives are as follows:
Zorlu case study:
Was centred on two operational problems relating to poor knowledge of physicochemical properties of very CO2-rich geothermal brines and carbonate scaling in surface pipelines and during re-injection.
To eliminate the lack of knowledge about the properties of the geothermal fluid, chemical composition, isotope chemistry and scale chemistry analysis were conducted for the solid, liquid, and gas forms of the geothermal fluid.
Optimizations were made for pipeline and inhibitor dosing inlcuding measurement on the scale thickness
Degassing pressures and well depths of non-condensable gases which are mainly composed of CO2 were found with the help of modelling studies
Inshiem case study:
Development of a joint thermodynamic modelling-field observation methodology and bringing new insights on three operational questions:
Gas Breakout Pressure (= Bubble point) on different operational conditions for the Insheim case study.
Pressure control for gas management.
Micro-degassing and corrosion processes correlation.
IDDP case study:
Scenario modelling for well siting of IDDP-3, including the first ever simulations that combined an existing reservoir model with explicitly represented magmatic heat sources
High quality models and simulations of utilization scenarios for both direct production and deep injection
Development and modelling of novel geochemical “pathfinders” to detect input of superhot fluids into the overlying, exploited conventional high-enthalpy reservoir by analyzing conventional fluid sampled from this.
GEOPRO impacts include:
1) Optimized energy extraction from existing systems (through tighter controls allowing strategically reduced safety margins) to remain within the production constraints of scaling, corrosion etc.
2) Reduced OPEX costs through the ability to thermodynamically minimise scale formation at key points (flash points, heat exchangers, lower temperature reinjection) through control-oriented modeling
3) The ability to better design well layouts, pipe dimensions, coatings using dynamic multi-phase geothermal flow assurance simulations coupled with a Knowledge Based Engineering (KBE) tool
4) Improved knowledge of reservoir fluid characteristics, allowing more accurate chemical thermometry and enthalpy calculations, and the ability to “vector in” onto productive reservoirs during exploration
5) Improving the ability to expand the reinjection technology of waste water and green-house gases like CO2, H2S and CH4 that are currently being emitted to the atmosphere
6) The GEOPRO Flow Loop's Potential: Multi-phase fluids, comprising vapor and brine, constitute an integral component of numerous geothermal systems and industries. The interaction between these fluid phases typically affects the physical and chemical properties of the fluid, potentially resulting in operational challenges such as pressure fluctuations, cavitation, mineral scaling, corrosion, and overall transport efficiency. Nevertheless, characterizing multi-phase flow and optimizing operational conditions can be challenging due to the harsh environmental conditions prevalent in typical geothermal industries. As part of the GEOPRO project, a flow loop was designed and constructed specifically for geothermal applications aimed to test optimal flow regimes under relevant conditions. Through experiments, the flow loop successfully demonstrated its capability to measure various parameters under multiphase flow conditions, including and their impact on the flow processes of geothermal fluids. These flow-loop tests serve as proof-of-concept, demonstrating some of the invaluable capabilities of the flow loop for geothermal energy research and development. Notably, flow loop tests, which were originally introduced in the oil and gas industry over 40 years ago, have never been utilized in geothermal applications until now. These tests offer insights into flow regimes concerning temperature and pressure, provide an understanding of fluid cavitation, and shed light on the effects of scale formation on fluid flow. Furthermore, flow loops can play a pivotal role in evaluating new instruments and sensors for in-situ and ex-situ monitoring of fluid flow in pipelines. This understanding, in turn, can be leveraged to optimize geothermal operations, minimizing and preventing potential issues and reducing costs.
1) Optimized energy extraction from existing systems (through tighter controls allowing strategically reduced safety margins) to remain within the production constraints of scaling, corrosion etc.
2) Reduced OPEX costs through the ability to thermodynamically minimise scale formation at key points (flash points, heat exchangers, lower temperature reinjection) through control-oriented modeling
3) The ability to better design well layouts, pipe dimensions, coatings using dynamic multi-phase geothermal flow assurance simulations coupled with a Knowledge Based Engineering (KBE) tool
4) Improved knowledge of reservoir fluid characteristics, allowing more accurate chemical thermometry and enthalpy calculations, and the ability to “vector in” onto productive reservoirs during exploration
5) Improving the ability to expand the reinjection technology of waste water and green-house gases like CO2, H2S and CH4 that are currently being emitted to the atmosphere
6) The GEOPRO Flow Loop's Potential: Multi-phase fluids, comprising vapor and brine, constitute an integral component of numerous geothermal systems and industries. The interaction between these fluid phases typically affects the physical and chemical properties of the fluid, potentially resulting in operational challenges such as pressure fluctuations, cavitation, mineral scaling, corrosion, and overall transport efficiency. Nevertheless, characterizing multi-phase flow and optimizing operational conditions can be challenging due to the harsh environmental conditions prevalent in typical geothermal industries. As part of the GEOPRO project, a flow loop was designed and constructed specifically for geothermal applications aimed to test optimal flow regimes under relevant conditions. Through experiments, the flow loop successfully demonstrated its capability to measure various parameters under multiphase flow conditions, including and their impact on the flow processes of geothermal fluids. These flow-loop tests serve as proof-of-concept, demonstrating some of the invaluable capabilities of the flow loop for geothermal energy research and development. Notably, flow loop tests, which were originally introduced in the oil and gas industry over 40 years ago, have never been utilized in geothermal applications until now. These tests offer insights into flow regimes concerning temperature and pressure, provide an understanding of fluid cavitation, and shed light on the effects of scale formation on fluid flow. Furthermore, flow loops can play a pivotal role in evaluating new instruments and sensors for in-situ and ex-situ monitoring of fluid flow in pipelines. This understanding, in turn, can be leveraged to optimize geothermal operations, minimizing and preventing potential issues and reducing costs.