SYNGAS CAPABLE COMBUSTION SYSTEMS DEVELOPMENT FOR ADVANCED GAS TURBINES
In the age of volatile and ever increasing natural gas fuel prices, strict new emission regulations and technological advancements, modern IGCC plants are the answer to growing market demands for efficient and environmentally friendly power generation. IGCC technology allows the use of low cost opportunity fuels, such as coal, of which there is a more than a 200-year supply in the U.S., and refinery residues, such as petroleum coke and residual oil. Future IGCC plants are expected to be more efficient and have a potential to be a lower cost solution to future CO2 and mercury regulations compared to the direct coal fired steam plants. Siemens has more than 300,000 hours of successful IGCC plant operational experience on a variety of heavy duty gas turbine models in Europe and the U.S. The gas turbines involved range from SGT5-2000E to SGT63000E (former designations are shown on Table 1). Future IGCC applications will extend this experience to the SGT5-4000F and SGT6-4000F/5000F/6000G gas turbines. In the currently operating Siemens’ 60 Hz fleet, the SGT6-5000F gas turbine has the most operating engines and the most cumulative operating hours. Over the years, advancements have increased its performance and decreased its emissions and life cycle costs without impacting reliability. Development has been initiated to verify its readiness for future IGCC application including syngas combustion system testing. Similar efforts are planned for the SGT6-6000G and SGT5-4000F/SGT6-4000F models. This paper discusses the extensive development programs that have been carried out to demonstrate that target emissions and engine operability can be achieved on syngas operation in advanced F-class 50 Hz and 60 Hz gas turbine based IGCC applications.
Flow Simulation and Optimization of an Integrated Gasification Combined Cycle for Coal Gas, Heat and Power
A polygeneration system based on a coal integrated gasification combined cycle (IGCC) for coal gas, heat and power is proposed. State parameters and procedure parameters for the polygeneration system were obtained by flow simulation using Aspen Plus as a platform. The initial performance of the system was evaluated in terms of the thermal efficiency of the combined cycle, the integrated energy utilization coefficient and the profit per day of operation of the polygeneration system; the simulation results gave values for these parameters of 38.41%, 76.06%, and 816,070 $/day, respectively. Optimization models with seven operating variables and different optimization objective functions were established in order to realize flow optimization. The optimum values of the thermal efficiency of the combined cycle, integrated energy utilization coefficient of the polygeneration system, and the profit per day of operation of the polygeneration system after optimization were 44.99%, 81.3%, and 897,700 $/day respectively, corresponding to increases of 17%, 7%, and 10%, respectively.
Measurement and Demonstration of Thermal Expansion Coefficient
There are many classroom demonstrations, such as the ball-and-ring experiment, for showing the existence of thermal expansion of solids. The coefficient of linear expansion α (= increase in length divided by the original length times the change in temperature) may be measured in high school laboratories using a number of methods.1–4 In this paper we describe an especially simple experiment for determining α for a metal rod. It is based on the well-known optical lever method and is suitable for either a laboratory experiment or a classroom exercise.