17 - Dynamic IGCC system simulator

This study identifies vital gas turbine (GT) parameters and quantifies their influence in meeting the DOE Turbine Program overall Integrated Gasification Combined Cycle (IGCC) plant goals of 50% net HHV efficiency, $1000/kW capital cost, and low emissions. The project analytically evaluates GE advanced F class air cooled technology level gas turbine conceptual cycle designs and determines their influence on IGCC plant level performance including impact of Carbon capture. This report summarizes the work accomplished in each of the following six Tasks. Task 1.0--Overall IGCC Plant Level Requirements Identification: Plant level requirements were identified, and compared with DOE's IGCC Goal of achieving 50% Net HHV Efficiency and $1000/KW by the Year 2008, through use of a Six Sigma Quality Functional Deployment (QFD) Tool. This analysis resulted in 7 GT System Level Parameters as the most significant. Task 2.0--Requirements Prioritization/Flow-Down to GT Subsystem Level: GT requirements were identified, analyzed and prioritized relative to achieving plant level goals, and compared with the flow down of power island goals through use of a Six Sigma QFD Tool. This analysis resulted in 11 GT Cycle Design Parameters being selected as the most significant. Task 3.0--IGCC Conceptual System Analysis: A Baseline IGCC Plant configuration was chosen, and an IGCC simulation analysis model was constructed, validated against published performance data and then optimized by including air extraction heat recovery and GE steam turbine model. Baseline IGCC based on GE 207FA+e gas turbine combined cycle has net HHV efficiency of 40.5% and net output nominally of 526 Megawatts at NOx emission level of 15 ppmvd{at}15% corrected O2. 18 advanced F technology GT cycle design options were developed to provide performance targets with increased output and/or efficiency with low NOx emissions. Task 4.0--Gas Turbine Cycle Options vs. Requirements Evaluation: Influence coefficients on 4 key IGCC plant level parameters (IGCC Net Efficiency, IGCC Net Output, GT Output, NOx Emissions) of 11 GT identified cycle parameters were determined. Results indicate that IGCC net efficiency HHV gains up to 2.8 pts (40.5% to 43.3%) and IGCC net output gains up to 35% are possible due to improvements in GT technology alone with single digit NOx emission levels. Task 5.0--Recommendations for GT Technical Improvements: A trade off analysis was conducted utilizing the performance results of 18 gas turbine (GT) conceptual designs, and three most promising GT candidates are recommended. A roadmap for turbine technology development is proposed for future coal based IGCC power plants. Task 6.0--Determine Carbon Capture Impact on IGCC Plant Level Performance: A gas turbine performance model for high Hydrogen fuel gas turbine was created and integrated to an IGCC system performance model, which also included newly created models for moisturized syngas, gas shift and CO2 removal subsystems. This performance model was analyzed for two gas turbine technology based subsystems each with two Carbon removal design options of 85% and 88% respectively. The results show larger IGCC performance penalty for gas turbine designs with higher firing temperature and higher Carbon removal.

This paper presents the results of cost of energy (COE) analysis of integrated gasification combined cycle (IGCC) power plant with respect to CO 2 capture ratio under climate change scenarios. In order to obtain process data for COE analysis, IGCC power plant and IGCC with carbon capture and sequestration (CCS) power plant have been simulated and modeled using Aspen Plus, and verified using various materials such as related reports, papers and simulation guide lines. The concept of 20-year levelized cost of energy (LCOE), and climate change scenarios suggested by International Energy Agency (IEA) are adopted to compare the COE of IGCC power plants with respect to CO 2 capture ratio more realistically. In this study, LCOEs which consider fuel price and CO 2 price changes with respect to the climate change scenarios are proposed in order to increase the reliability of economic comparison. And results of proposed LCOEs of IGCC without CCS power plant and IGCC with CCS (30% and 70% capture-mole basis- of CO 2 in syngas stream) power plant are presented.

CO2 capture (CC) using hot K2CO3 solvent in integrated gasification combined cycle (IGCC) plant is a promising technology for CO2 emission reduction. Based on pilot scale trials, an innovative IGCC system with CC using hot K2CO3 solvent is proposed, in which the intercooling heat between CO2 compressors is recovered for CO2 regeneration (IGCC + CC + HR). Thermodynamic performance and exergy and energy utilization diagram (EUD) analysis are presented. Results show that recovery of the intercooling heat between CO2 compressors reduces the steam extraction requirement from turbines for CO2 regeneration by around 18% and enhances the efficiency of IGCC with CO2 capture (IGCC + CC) plant by 0.3–0.7 percentage points. With 90% CC, the efficiency of the IGCC + CC + HR plant is around 35.4% which is higher than IGCC + CC plant using Selexol technology. Compared to IGCC, the energy penalty for CC in IGCC + CC + HR plant is mainly caused by the exergy losses in CO2 separation (45.2%), water gas shift (WGS) (28.5%), combined cycle (20.7%) and CO2 compression units (5.6%). EUD analysis shows that the IGCC + CC + HR plant realizes good match of the energy levels between the intercooling heat and the recovered steam for CO2 regeneration, thereby obviously reducing the exergy losses in CO2 compression and separation units and improving the plant efficiency. The results presented in this paper confirm the sources causing the energy penalty for CC in IGCC power plant and the new IGCC + CC + HR system helps to reduce the energy penalty for CC in IGCC power plant based on solvent technologies.

ePHASORsim tool offers real-time dynamic simulations for transmission and distribution power systems. Applications such as contingency studies, testing control devices, operator training, and SCADA system tests are examples for employing this tool. This paper describes the hardware and software architecture of the ePHASORsim and its development. The accuracy of the tool has been evaluated in comparison to other commercial, but non-real-time, simulation packages for both transmission and distribution systems. Its real-time performance has been tested with a time-step of 10ms on a real-time simulator for large-scale power systems in the order of 20000 buses, 5000 generators, and over 9000 control devices.

Bridging the Experience Gap - How do we migrate Skills and Knowledge between the Generations?

The goal of this study is to evaluate the economic and environmental performance of power plants based on integrated gasification combined cycle (IGCC) technology, and to compare it with currently relevant renewable and nuclear power generation options in China, until the year 2020. First, electricity demand is predicted, based on up-to-date policies made by Chinese government organizations. From this, a business as usual (BAU) study, in which coal-fired power plant technology is assumed to be unchanged from 2010 to 2020, is carried out as a reference. Different scenarios of IGCC technology adoption are then studied using a newly developed model, and the result show, for example, that there could be 10.05 billion tons of CO2 emission avoided from 2010 to 2020 if 50% of newly built coal-fired plants are based on IGCC technology with CO2 capture. When compared with other options, the cost of avoided CO2 emissions in this scenario is more expensive than hydroelectric, nuclear, and wind, but cheaper than solar (thermal and photovoltaic). The results also show that IGCC, although more expensive, could still be important in China’s coal-dominated electricity industry.

CO2 sorbents for a sorption-enhanced water–gas-shift process in IGCC plants: A thermodynamic analysis and process simulation study

Dynamic modelling and validation of pre-combustion CO2 absorption based on a pilot plant at the Buggenum IGCC power station

Around 50% of the world’s electrical power supply comes from the Rankine cycle, and the majority of existing Rankine cycle plants are driven by coal. Given how unattractive coal is as an energy resource in spite of its high energy content, it becomes necessary to find a way to utilize coal in a cleaner and more efficient manner. Designed as a potential retrofit option for existing Rankine cycle plants, the integrated mild/partial gasification combined (IMPGC) cycle is an attractive concept in cycle design that can greatly increase the efficiency of coal-based power plants, particularly for retrofitting an old Rankine cycle plant. Compared with the integrated gasification combined cycle (IGCC), IMPGC uses mild gasification to purposefully leave most of the volatile matters within the feedstock intact (hence, yielding more chemical energy) compared with full gasification and uses partial gasification to leave some of the remaining char un-gasified compared with complete gasification. The larger hydrocarbons leftover from the mild gasification process grant the resulting syngas a higher volumetric heating value, leading to a more efficient overall cycle performance. This is made possible due to the invention of a warm-gas cleanup process invented by the Research Triangle Institute (RTI), called the high-temperature desulfurization process (HTDP), which was recently commercialized. The leftover char can then be burned in a conventional boiler to boost the steam output of the bottom cycle, further increasing the efficiency of the plant up to 47.9% (based on lower heating value, or LHV). This paper will first analyze the individual concepts used to create the baseline IMPGC model, including the mild and partial gasification processes themselves, the warm-gas cleanup system, and the integration of the boiler with the heat recovery steam generator (HRSG). This baseline will then be compared with four other common types of power plants, including subcritical and ultra-supercritical (USC) Rankine cycles, IGCC, and natural gas. The results show that IMPGC consistently outperforms all other forms of coal-based power. IMPGC is more efficient than the standard subcritical Rankine cycle by nine percentage points, more than a USC Rankine cycle by nearly four points, and more than IGCC by seven points.

00/00446 Comparison between IGCC and supercritical power plant processes

In this paper, a systematic approach to design the control system of a commercial-scale integrated gasification combined cycle (IGCC) power plant with CO2 capture is considered. The control system design is developed with the objective of optimizing a desired scalar function while satisfying operational and environmental constraints in the presence of measured and unmeasured disturbances. Various objective functions can be considered for the control system design such as maximization of profit, maximization of the power produced, or minimization of the auxiliary power consumed in the plant. The design of such a control system can make the IGCC plant suitable to play an active role in the smart grid era by enabling operation in the load-following mode as demand for electricity from the grid fluctuates over time. In addition, other penalty functions such as emission penalties for CO2 or other criteria pollutants can be considered in the control system design.;The control system design is performed in two stages. In the first stage, a top-down analysis is used to generate a list of controlled, manipulated, and disturbance variables considering a scalar operational objective and other process constraints. In this section, innovative methods devised for primary and secondary controlled variable selection will be discussed.Exploiting these results, the second stage uses a bottom-up approach for simultaneous design of the control structure and the controllers. In this section, a novel means of control structure design has been proposed.;In this research, the proposed two-stage control system design approach is applied to the IGCC's acid gas removal (AGR) process which uses the physical solvent Selexol(TM) to selectively remove CO2 and H2S from the shifted syngas. Aspen Plus DynamicsRTM is used to develop the AGR process model while MATLABRTM is used to perform the control system design. This work has shown the proposed design procedure for plantwide control yields an optimal control structure. Additionally, the methods proposed in this work for primary and secondary controlled variable selection yield controlled variables which balance economic and control performance. Finally, the method proposed for control structure design has been found to yield a control structure that balance the control performance with controller complexity.

Over the last years, with the rapid development of 3D Web technologies, such as Web3D, HTML5 and WebGL, have allowed complex 3D scenes to be rendered interactively, within a web browser. Compared to the traditional virtual training system, the traing system with WebGL, which requires no explicit installation plug-in and is able to achieve cross-platform easily, is getting more and more popular. This foundation has made it possible to build powerful the virtual acupuncture training system. However, designing and implementing a complete virtual training system using WebGL is not straightforward and complex. In this paper, the author presents a virtual acupuncture training system that using WebGL and Three.js 3D Engine. It can be used to learn acupuncture, and also give ordinary people a reference. Our experiment result shows that WebGL and Three.js 3D Engine can easily support the virtual acupuncture training system, and have a good response. By using this system, the trainers can be more familiar with the acupoint of the human body. At the same time, the trainer will improve his ability in acupuncture therapy. We also hope to provide some references for the development of the virtual training system.

Membrane performance requirements for carbon dioxide capture using hydrogen-selective membranes in integrated gasification combined cycle (IGCC) power plants

The overall objective of the project is to demonstrate the technical and economic viability of a new Integrated Gasification Combined Cycle (IGCC) power plant designed to efficiently process low rank coals. The plant uses an integrated CO2 scrubber/Water Gas Shift (WGS) catalyst to capture over90 percent capture of the CO2 emissions, while providing a significantly lower cost of electricity (COE) than a similar plant with conventional cold gas cleanup system based on SelexolTM technology and 90 percent carbon capture. TDA’s system uses a high temperature physical adsorbent capable of removing CO2 above the dew point of the synthesis gas and a commercial WGS catalyst that can effectively convert CO in The overall objective of the project is to demonstrate the technical and economic viability of a new Integrated Gasification Combined Cycle (IGCC) power plant designed to efficiently process low rank coals. The plant uses an integrated CO2 scrubber/Water Gas Shift (WGS) catalyst to capture over90 percent capture of the CO2 emissions, while providing a significantly lower cost of electricity (COE) than a similar plant with conventional cold gas cleanup system based on SelexolTM technology and 90 percent carbon capture. TDA’s system uses a high temperature physical adsorbent capable of removing CO2 above the dew point of the synthesis gas and a commercial WGS catalyst that can effectively convert CO in bituminous coal the net plant efficiency is about 2.4 percentage points higher than an Integrated Gasification Combined Cycle (IGCC) plant equipped with SelexolTM to capture CO2. We also previously completed two successful field demonstrations: one at the National Carbon Capture Center (Southern- Wilsonville, AL) in 2011, and a second demonstration in fall of 2012 at the Wabash River IGCC plant (Terra Haute, IN). In this project, we first optimized the sorbent to catalyst ratio used in the combined WGS and CO2 capture process and confirmed the technical feasibility in bench-scale experiments. In these tests, we did not observe any CO breakthrough both during adsorption and desorption steps indicating that there is complete conversion of CO to CO2 and H2. The overall CO conversions above 90 percent were observed. The sorbent achieved a total CO2 loading of 7.82 percent wt. of which 5.68 percent is from conversion of CO into CO2. The results of the system analysis suggest that the TDA combined shift and high temperature PSA-based Warm Gas Clean-up technology can make a substantial improvement in the IGCC plant thermal performance for a plant designed to achieve near zero emissions (including greater than 90 percent carbon capture). The capital expenses are also expected to be lower than those of Selexol. The higher net plant efficiency and lower capital and operating costs result in substantial reduction in the COE for the IGCC plant equipped with the TDA combined shift and high temperature PSA-based carbon capture system.

Waste heat recovery process designs and performance analyses are conducted on the IGCC(Integrated Gasification Combined Cycle) power plants integrated with two different coal gasification and gas cleanup processes by Shell and GE/Texaco. Through the analysis results, the present study provides the steam integration concept between the HRSG and the chemical processes of IGCC power plant, and investigates the effect of steam integration on the power generation of IGCC power plant. The present simulation results show less steam power output and higher overall IGCC efficiency of the Shell-based power plant than the GE/Texaco.