The capabilities of the chemical recuperation of exhaust and compressor intercooling heat from gas turbines have been investigated in this paper considering methanol as primary fuel for the Reheat ...InterCooled (intercooler heat is recovered) Aeroderivative Gas Turbine. The model includes an exergy analysis method and a simplified blade cooling model. The location of the intercooler, the reheat combustion chamber as well as the overall pressure ratio have been optimized. Comparisons are made with the Chemically Recuperated Gas Turbine CRGT cycles using methane as a primary fuel.
Micro-turbine generators (MTG) represent a useful and promising mean to achieve energy recovery in distributed generation power systems. In order to fully exploit their potential a detailed knowledge ...of their design and off-design performance must be gained, in order to properly plan their control strategy and achieve an effective integration in the power system and an optimization of its components. In the present work, electrical measurements have been carried out to characterize a commercial MTG 3-phase power output and therefore, its overall performance. An inverter was adopted to control the turbine rotating speed, through the variation of the breaking load, and its behavior was evaluated as well. Special attention was paid to provide a MTG regulation strategy that allows to maximize the specific output power, for the required load, by regulating the turbine speed. Proof-of-concept evaluations revealed that the developed strategy allows to reduce the compressed air consumption, with respect to a baseline fixed-speed regulation, and therefore optimize the power system characteristics.
An innovative gas turbine cycle is studied, which can offer several advantages from the point of view of environmental friendship and peakload shaving capabilities. The basic idea of SCGT/CC is of ...cooling down the exhaust to temperatures as low as to allow full condensation of the water vapor; a large part of the exhaust gases is then recirculated to the compressor; the condensed water can be reinjected by means of a pump at compressor delivery. For maximum performance it is convenient not to inject this water flow, but rather to use it for other purposes; however, water injection produces a power boosting effect (at the expense of a small decrease in efficiency) which can be useful for peakload shaving applications. The working gas composition in the GT cycle is that corresponding to stoichiometric combustion, which opens the possibility of applying techniques for CO
2 recycling and general exhaust gas treatment. The cycle guarantees a high level of efficiency, and its adoption should imply minor modifications to existing equipment.
With the steady rises in maximum gas turbine cycle temperatures, cooled expansion is receiving more and more attention from researchers and industry. Several mathematical-physical models were ...developed in the course of an investigation of the effects of cooling on cycle performance. The results show that the first law and second law (exergy) approaches are not alternatives but complementary in gaining insight into the thermodynamic effects of such cooling on the cycle.
Estimating potential electric power generation in the pulping industry by implementing black liquor gasification combined cycle (BLGCC) technology is an important issue, given the anticipated future ...demand for “green” electricity. Full-scale BLGCC technology has not yet been commercially demonstrated. Therefore, performance studies of this technology require the use of computer simulation tools, with the pertaining challenge of simulating gas turbine operation on gasified black liquor fuel. Exact future plant size is usually unknown; therefore many studies adopt a simplified model assuming an engine sized to match the available fuel stream, with generic characteristics representative of a given class of engine. The performance of a fixed size engine operating at off-design conditions on low calorific value fuel is in most cases lower. This work attempts to quantify the resulting difference between performance estimates based on these two assumptions. The calculations are performed for a BLGCC powerhouse integrated with the Swedish KAM reference pulp mill, for which the biofuel (bark and black liquor) available on-site is more than sufficient to satisfy the mill steam demand. The surplus can therefore be used for additional power generation, which however implies the use of low efficiency condensing steam turbine units. Alternatively, surplus biofuel can be exported for use elsewhere. This study investigates both of these options.
Abstract
A number of innovative gas turbine cycles have been proposed lately, including the humid air turbine (HAT) and the chemically recuperated gas turbine (CRGT). The potential of the CRGT cycle ...lies in the ability to generate power with a high efficiency and ultra-low NOx emissions. Much of the research work published on the CRGT cycle is restricted to an analysis of the thermodynamic potential of the cycle. However, little work has been devoted to discussion of some of the relevant design and operation issues of such cycles. In this paper, part-load performance characteristics are presented for a CRGT cycle based on an aeroderivative gas turbine engine adapted for chemical recuperation. The paper also includes discussion of some of the design issues for the methane-steam reformer component of the cycle. The results of this study show that large heat exchange surface areas and catalyst volumes are necessary to ensure sufficient methane conversion in the methane steam reformer section of the cycle. The paper also shows that a chemically recuperated aeroderivative gas turbine has similar part-load performance characteristics compared with the corresponding steam-injected gas turbine (STIG) cycle.
Significant research efforts are currently centered on developing advanced gas turbine systems for electric power generation applications. Gas–steam combined cycles are often used to obtain a high ...efficiency power plant. Two innovative gas turbine technologies have recently been proposed for combined cycle applications. Two gas–steam combined cycles using thermodynamic analysis are presented: a combined cycle with three pressure levels with reheat heat recovery boiler is used with two different gas turbine technologies (high pressure ratio and reheat against “H” technology). This analysis constitutes a comparison not only between two different constructive solutions but also between two different gas turbine (GT) techniques (reheat and GT steam cooling) and technologies (a consolidated and an advanced gas turbine technology) applied to a combined cycle.
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