TECHNICAL PAPERS PREPARED BY GRYPHON
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technical papers prepared by Gryphon. For an abstract of a paper, please click on its
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Gryphon could potentially make arrangements to present these papers or workshop at your
Cogeneration is the
simultaneous production of two or more forms of useful energy, usually
electricity and heat, from a single fuel source. In the early 1900's, many
industries employed cogeneration in the absence of economically viable
alternatives for the production of process heat and electricity. With the
development of large central generating stations and reliable electrical
distribution systems, interested in cogeneration waned. Industries found it more
economical to produce their own process heat and to purchase their electricity,
rather than use self-generation.
Today in a world of
global competition, high costs of purchased power and concern for the
environment, many industries are once again turning to cogeneration. The
waste heat associated with many processes is being harnessed and used to
generate electricity either for sale to a utility or for self-generation.
Conversely, many industries are using a waste product as a fuel or are
increasing their current fuel usage for the purpose of generating
electricity. The waste heat associated with this operation is then harnessed
to provide process heat. The net effect of either approach has been a new
source of revenue (the sale of electricity) or the lowering of operating
costs (the displacement of process heat or the reduction of electricity
purchases). The economic incentive in some instances is so great as to
promote large electrical generating installations even in excess of the
industrial user's own requirements.
This paper outlines the
fundamental principles of Cogeneration, with illustrations of Topping and
Bottoming cycles, a number of common cogeneration cycles that can be
employed in industrial applications and for developer applications,
demonstrations of the application of Heat-to-Power Ratios, and tabulations
of the performance of typical prime movers in a number of cycles.
This information taken
together will permit the reader to evaluate which cogeneration system may
best serve a given application.
This paper describes how gas turbines can be applied into service for either:
a) electrical power generation, or
b) mechanical drive application,
considering both technical and simplified economic
For a starting point, in the Electrical Power Generation
section, a BASE CASE for a typical industrial facility is described, illustrating the
plant's existing electrical power usage, steam production and fuel usage profiles, without
Sequential examples, with illustrations and simplified
calculations are then given, showing how a gas turbine generator (GTG) could be integrated
into the Base Case* facility, to ultimately save money. The examples progressively
increase in complexity, flexibility, cost and efficiency, and include:
- GTG in Open Cycle Configuration
- GTG with Unfired HRSG
- GTG with Fired HRSG
- Small Combined-Cycle Cogeneration Plant
- Large Combined-Cycle Cogeneration Plant
In the Mechanical Power Applications
section, the BASE CASE scenario is a typical Utility Pipeline Gas Compressor application
using a mechanical drive gas turbine. Sequential examples are then given showing how
combined-cycle using steam turbine generators could be applied to the typical plant.
The paper finishes with general discussions
on Turbine Selection Criteria, including turbine sizing considerations and aero-derivative
vs. heavy-duty industrial comparisons.
* For an illustration of how a steam turbine
generator could be integrated into the same Base Case facility, please refer to the Steam
Turbine Applications © paper.
This paper describes how steam turbines can be applied into service for
a) electrical power
b) mechanical drive application,
considering both technical and simplified
starting point in the Electrical Power Generation section, a BASE
CASE for a typical industrial facility is described, illustrating the
plant's existing electrical power usage, steam production and fuel usage
profiles, without cogeneration.
Sequential examples, with illustrations,
extraction maps and simplified calculations are the given, showing how a
steam turbine generator (STG) could be integrated into the Base Case*
facility, to ultimately save money. The examples progressively increase in
complexity, flexibility and cost, and decrease in overall efficiency, and
- Backpressure STG
- Condensing STG
- Combined Cycle Cogeneration Plant - including a gas
turbine generator and heat recovery steam generator.
Mechanical Power Applications
section, a simple cost-and-performance illustration of the replacement of
electric motor driven boiler feedwater pumps and boiler FD fans, with
mechanical-drive steam turbines is provided.
The paper finishes with a general
discussion on steam piping, turbine auxiliaries and exhaust/condenser
* For an illustration of how a gas turbine
generator could be integrated into the same Base Case facility, please refer
to the Gas Turbine Applications © paper.
Steam Turbine Bypass Systems
by Robert W. Anderson (Progress Energy Inc),
and Henk van Ballegooyen
The often excellent
operation of large gas turbine generators, multi-pressure reheat heat recovery steam
generators and steam turbine generators in large combined-cycle power plants operated at
100% load, can sometimes become awkward and troublesome during transient conditions of
startup, low-load, steam turbine trip and shutdown conditions.
This article discusses
steam turbine bypass systems, sparger tubes, steam attemperation control, condenser
dump-bypass system design, and noise problems in regard to current HEI, EPRI and overseas
design practices and provides recommendations for future plant designs.
Open the Steam Turbine Bypass Systems Article (hosted at http://www.psimedia.info)
This paper describes the many types of
condensing systems which can be installed on the exhaust of condensing-type steam
turbines, depending upon the type of condensing application and/or location of the
Although condensing systems may have some
technical variances, they all strive for the same basic result - lowering turbine exhaust
pressure in order to reduce the exhaust steam enthalpy, thus increasing system power
output, and increasing cycle efficiency.
This paper presents and illustrates brief
descriptions of several types of condensers and some of their applications.
Maintenance issues and materials of
construction are also briefly outlined.
Gryphon has encountered, with many of its clients, a general
lack of consensus on a future strategy for their Heating and/or Chilled Water
Systems. As an engineering company which specializes in power plants,
cogeneration and chiller systems, we are often requested to carry out studies to
determine if cogeneration is viable or if a piping distribution system should be
upgraded. Only in a few instances, however, have we been requested to analyze
and model the entire heating or cooling system to provide a baseline performance
and economic model of the system which can be used as a basis for decisions.
Without a total system approach, options tend to be evaluated individually. A
total energy/total plant perspective provides a method to determine what effects
changes in operation will have on present performance and economics and to allow
multiple options to be investigated to provide the client with a true picture of
the process for future operations.
This paper presents an example of a total
system model which allows various scenarios to be investigated. It provides a client with
concrete information on the effects of centralized or decentralized expansion, sizing of
future units based on load growth forecasts, unit retirement schedules, possible fuel
types, possible prime mover types, efficiency vs. capital cost comparisons, as well as
other options. The total system modeling method provides the client with an analysis, in a
graphical and tabular format, of the options that should be considered and the type of
future expansion that provides the best opportunities and least risks.
Plant Efficiency by Better Maintenance paper was originally prepared
for the EPIC Educational Programs Innovations Center Boiler Plant Efficiency
Seminar in Toronto, in November 1997.
The first section of this paper
reviews the establishment of a computerized maintenance / materials management
system (MMS) for a boiler plant. The MMS discussed is based on the system that
is being implemented at the Northland Power Iroquois Falls Cogeneration Plant,
for which Gryphon acted as the Independent Engineer. Topics covered include:
|a) Plan Objectives,
b) Plan Structure,
|d) Work Order System,
e) Materials Management,
f) Administrative Features.
The second section of this paper
examines maintenance items that should be included in a maintenance program
aimed at preserving boiler efficiency. Emphasis is placed on maintenance of the
combustion process, particularly excess air levels. In this regard, maintenance
of firing equipment and combustion controls is first examined. Other items such
as fireside cleanliness air and gas leaks and blowdown are also discussed.
This Boiler Plant Replacement and Retrofit - Case
Studies paper was originally prepared for the EPIC Educational Programs
Innovations Center Boiler Plant Efficiency Seminar in Toronto, in November 1997.
This paper reviews two (2) recent boiler replacement and
retrofit projects that Gryphon International Engineering Services Inc.
In the first project reviewed, a completely new replacement
boiler plant was installed at the Henderson General Division of the Hamilton
Civic Hospitals, Hamilton, Ontario. The new boiler plant contained three new "D"
type package boilers rated at 15,000, 25,000, and 30,000 lb/hr of 125 psig
saturated steam. The boilers were equipped with low-NOx, parallel flow burners
that were designed to utilize Induced Flue Gas Recirculation (IFGR). Also
included in the plant were new makeup, feedwater, and condensate systems, as
well as a Bailey Infi 90 Distributed Control System (DCS).
In the second project reviewed, two (2) new 110,000 lb/hr, 400
psig, 600 deg F package boilers were installed to replace existing boilers at
Cornell University's Central Heating Plant in Ithaca, New York. Engineering was
also provided for the removal of two existing boiler feedwater pumps and
subsequent installation of a new steam turbine-driven feedwater pump, the
installation of a new pressure reducing-desuperheating station, plus the
expansion and upgrading of the DCS, and extensive building modifications.
The paper finishes with reasons for retrofits, and examples of
potential types of boiler retrofits are also discussed.
Today's social and economic pressures drive boiler owners and
operators to achieve better energy efficiency while maintaining or improving
emissions. Rapidly evolving environmental regulations in Ontario complicate the
task of assessing and implementing appropriate emissions control technologies.
This paper presents a summary of environmental guidelines,
rules, and regulations presently in Ontario for boilers. Proposed new rules and
regulations and those being implemented are also presented. The review focuses
on recent and proposed changes which impact boiler owners and operators.
The paper also discusses the various boiler air pollutants
and methods to control and minimize those pollutants.
The performance characteristics of a gas turbine engine or Gas
Turbine Generator package (GTG) depends upon the type and model of engine being
examined, the location at which it will be installed, the ambient conditions
under which it will operate, and the fuel(s) and NOx suppression methods which
will be utilized.
This paper is a primer presenting an explanation of typical
gas turbine and GTG package rating methods and why and how they are corrected,
so that an accurate real-life picture of the performance envelope of a unit can
be determined for the examiner's evaluation.
This Cogeneration and Combined-Cycle
Principles Workshop provides an overview introduction to cogeneration and
combined-cycle powerplants, including primers on gas turbines; heat recovery steam
generators; steam turbines & condensers; methodologies for executing a plant from
conception through to synchronization and operation; and operations and maintenance
concepts. Typical examples of simple-cycle, cogeneration, combined-cycle and
combined-cycle cogeneration plants are provided.
Chapter 1 Principles of Cogeneration
- The Case for Cogeneration
- Basic Cogeneration Cycles
- Process Heat-to-Power Ratio
- Cogeneration Cycle Efficiency
- Typical Cogeneration Applications
Chapter 2 Introduction to Gas Turbines
- Gas Turbine Concepts
- The Gas Turbine Assembly
- The Gas Turbine Package
- Newest Gas Turbine Technologies
Chapter 3 Introduction to HRSGs
- Fundamental Parts of the HRSG
- Types of HRSGs
- Single vs. Multi-Pressure HRSGs
- Unfired vs. Fired HRSGs
- Post-Combustion Emissions Controls
Chapter 4 Introduction to Steam
Turbines and Condensers
- Steam Turbine Concepts
- Steam Turbine Exhaust Configurations
- Extraction, Admission and Reheat Considerations
- Steam Turbine Cylinder Configurations
- Types of Condensing Systems
Chapter 5 Execution and Applications
- Project Execution Process
- Identifying the Opportunity
- Developing the Project
- Planning and Financing
- Design and Construction
- Commissioning and Startup
Chapter 6 – Operations and Maintenance
- O&M Concepts
- O&M Options
- O&M Considerations