Advanced Power Plant Development and Analyses Methodologies

Abstract

Under the sponsorship of the U.S. Department of Energy/National Energy Technology Laboratory, a multi-disciplinary team led by the Advanced Power and Energy Program of the University of California at Irvine is defining the system engineering issues associated with the integration of key components and subsystems into advanced power plant systems with goals of achieving high efficiency and minimized environmental impact while using fossil fuels. These power plant concepts include "Zero Emission" power plants and the "FutureGen" H 2 co-production facilities. The study is broken down into three phases. Phase 1 of this study consisted of utilizing advanced technologies that are expected to be available in the "Vision 21" time frame such as mega scale fuel cell based hybrids. Phase 2 includes current state-of-the-art technologies and those expected to be deployed in the nearer term such as advanced gas turbines and high temperature membranes for separating gas species and advanced gasifier concepts. Phase 3 includes identification of gas turbine based cycles and engine configurations suitable to coal-based gasification applications and the conceptualization of the balance of plant technology, heat integration, and the bottoming cycle for analysis in a future study. Also included in Phase 3 is the task of acquiring / providing turbo-machinery in order to gather turbo-charger performance data that may be used to verify simulation models as well as establishing system design constraints. The results of these various investigations will serve as a guide for the U. S. Department of Energy in identifying the research areas and technologies that warrant further support.

Sensitivity analysis of a Vision 21 coal based zero emission power plant

“…The gas exits the top of the gasifier riser and goes to a primary cyclone that is connected to a standpipe that receives the unreacted char and ash/bed material for recirculation back to the mixing zone. The overall carbon conversion for this O 2 blown ATR is assumed to be 95% based on information provided by Southern Services Company who operates the Wilsonville process demonstration unit [7].…”

“…The syngas is next further cooled against cooling water, and then compressed to the required pressure. A closed loop CO 2 system provides the gas required for pressurization of the lock hoppers, while the required make-up CO 2 is supplied from the captured CO 2 [7].…”

“…It also reduces the amount of heat exchange required within the SOFC system. Steam is added to the syngas upstream of the shift/membrane unit to avoid carbon deposition within that unit as well as in the downstream methanation reactor and in the reformer located within the SOFC stack [7].…”

“…The non-permeate is fed to a catalytic combustor using O 2 from the ITM unit to fully remove the small amounts of any remaining CO and H 2 , leaving CO 2 , H 2 O, and trace amount of O 2 in the stream. This stream is cooled and then pressurized (and dehydrated) to 15,200 kPa [7].…”

“…Calcium sulphide being an unstable compound is oxidized to calcium sulphate which is a stable compound. The heat generated is recovered by producing high pressure steam as well as preheating the combustion air required by the sulfator [7].…”