Design methodology of heat recovery steam generator in electric utility for waste heat recovery

In the present paper the design and performance of a waste heat recovery steam generator with variable gas flux is investigated based on second law. A method to calculate temperature and mass flow rate for design is proposed. The effects of the operating parameters and the structure parameters on the average entropy generation number are analyzed. The results show: (i) the average entropy generation number (Ns) decreases with the increase of no-dimensional heat capacities ratio and no-dimensional saturation temperature difference ratio; (ii) compare with the fluctuation of mass flow, fluctuation of temperature has larger effect on the Ns.; (iii) A larger steam parameter is suggested in order to decrease the entropy generation based on reasonable temperature difference and it is appropriate for the number of transfer units of the evaporator and economizer to be 2.5~3.

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Design methodology of organic Rankine cycle for waste heat recovery in cement plants

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2017.10.019 ◽

2018 ◽

Vol 129 ◽

pp. 421-430 ◽

Cited By ~ 14

Author(s):

Awais Ahmed ◽

Khaled Khodary Esmaeil ◽

Mohammad A Irfan ◽

Fahad Abdulrahman Al-Mufadi

Keyword(s):

Heat Recovery ◽

Waste Heat Recovery ◽

Design Methodology ◽

Waste Heat ◽

Organic Rankine Cycle ◽

Rankine Cycle

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Repowering of a Small Utility: A Unique Solution to a Unique Problem

Volume 1A: Gas Turbines ◽

10.1115/79-gt-15 ◽

1979 ◽

Author(s):

L. F. Fougere ◽

H. G. Stewart ◽

J. Bell

Keyword(s):

Steam Turbine ◽

Gas Turbine ◽

Steam Generator ◽

Gas Turbines ◽

Heat Recovery ◽

Electric Utility ◽

Combined Cycle ◽

Steam Boiler ◽

Heat Recovery Steam Generator ◽

Turbine Generator

Citizens Utilities Company’s Kauai Electric Division is the electric utility on the Island of Kauai, fourth largest and westernmost as well as northernmost of the Hawaiian Islands. As a result of growing load requirements, additional generating capacity was required that would afford a high level of reliability and operating flexibility and good fuel economy at reasonable capital investment. To meet these requirements, a combined cycle arrangement was completed in 1978 utilizing one existing gas turbine-generator and one new gas turbine-generator, both exhausting to a new heat recovery steam generator which supplies steam to an existing steam turbine-generator. Damper controlled ducting directs exhaust gas from either gas turbine, one at a time, through the heat recovery steam generator. The existing oil-fired steam boiler remains available to power the steam turbine-generator independently or in parallel with the heat recovery steam generator. The gas turbines can operate either in simple cycle as peaking units or in combined cycle, one at a time, as base load units. This arrangement provides excellent operating reliability and flexibility, and the most favorable economics of all generating arrangements for the service required.

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Energy-Exergy Analysis of Solarized Triple Combined Cycle Having Intercooling, Reheating and Waste Heat Utilization

TECNICA ITALIANA-Italian Journal of Engineering Science ◽

10.18280/ti-ijes.650114 ◽

2021 ◽

Vol 65 (1) ◽

pp. 93-104

Author(s):

Onkar Singh ◽

Gaitry Arora ◽

Vinod Kumar Sharma

Keyword(s):

Ambient Temperature ◽

Steam Generator ◽

Gas Turbines ◽

Heat Recovery ◽

Waste Heat ◽

Rankine Cycle ◽

Maximum Energy ◽

Combined Cycle ◽

Heat Recovery Steam Generator ◽

Exergetic Efficiency

Heliostat-based solar thermal power system consisting of a combination of the Brayton cycle, Rankine cycle, and organic Rankine cycle is a potential option for harnessing solar energy for power generation. Among different options for improving the performance of solarized triple combined cycle the option of introducing intercooling and reheating in the gas turbine cycle and utilizing the waste heat for augmenting the power output needs investigation. Present study considers a solarized triple combined cycle with intercooling and reheating in gas turbines while using the heat rejected in intercooling in heat recovery vapour generator and heat recovery steam generator separately in two different arrangements. A comparison of two distinct cycle arrangements has been carried out based on Ist law and IInd law of thermodynamics with the help of thermodynamic parameters. Results show that triple combined cycle having intercooling heat used in heat recovery vapour generator offers maximum energy efficiency of 63.54% at 8 CPR & 300K ambient temperature and maximum exergetic efficiency of 38.37% at 14 CPR & 300 K. While the use of intercooling heat in heat recovery steam generator offers maximum energy and exergetic efficiency of 64.15% and 39.72% respectively at 16 CPR & 300 K ambient temperature.

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Comparison of Saturated and Superheated Steam Plants for Waste-Heat Recovery of Dual-Fuel Marine Engines

Energies ◽

10.3390/en13040985 ◽

2020 ◽

Vol 13 (4) ◽

pp. 985

Author(s):

Marco Altosole ◽

Giovanni Benvenuto ◽

Raphael Zaccone ◽

Ugo Campora

Keyword(s):

Natural Gas ◽

Steam Generator ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Superheated Steam ◽

Waste Heat ◽

Rankine Cycle ◽

Fuel Oil ◽

Dual Fuel ◽

Heavy Fuel Oil

From the working data of a dual-fuel marine engine, in this paper, we optimized and compared two waste-heat-recovery single-pressure steam plants—the first characterized by a saturated-steam Rankine cycle, the other by a superheated-steam cycle–using suitably developed simulation models. The objective was to improve the recovered heat from the considered engine, running with both heavy fuel oil and natural gas. The comparison was carried out on the basis of energetic and exergetic considerations, concerning various aspects such as the thermodynamic performance of the heat-recovery steam generator and the efficiency of the Rankine cycle and of the combined dual-fuel-engine–waste-heat-recovery plant. Other important issues were also considered in the comparison, particularly the dimensions and weights of the steam generator as a whole and of its components (economizer, evaporator, superheater) in relation to the exchanged thermal powers. We present the comparison results for different engine working conditions and fuel typology (heavy fuel oil or natural gas).

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A Heat Recovery Study: Application of Intercooler as a Feed-Water Heater of Heat Recovery Steam Generator

Volume 5: Energy Systems Analysis, Thermodynamics and Sustainability; NanoEngineering for Energy; Engineering to Address Climate Change, Parts A and B ◽

10.1115/imece2010-38917 ◽

2010 ◽

Author(s):

P. Shukla ◽

M. Izadi ◽

P. Marzocca ◽

D. K. Aidun

Keyword(s):

Steam Generator ◽

Gas Turbines ◽

Heat Recovery ◽

Waste Heat ◽

Feed Water ◽

Heat Recovery Steam Generator ◽

Steam Generation ◽

Water Heater ◽

Theoretical Support ◽

Recovery Study

This paper evaluates the possibility of combining an intercooled gas turbine power cycle with a steam turbine cycle and the application of the intercooler as a feed-water heater for the heat recovery steam generator. In advance gas turbines the intercooler is used to improve the overall efficiency of the simple cycle but a noticeable amount of heat is wasted to the atmosphere. However, this energy can be recovered by using the proposed method in the current study. Accordingly, a thermodynamic study is done to investigate the improvement in efficiency achieved by feed-water heating. First the effect of intercooler parameters on the outlet condition of the water is studied. The bottoming cycle is then studied in details for the effect of feed-water temperature. An estimate of the energy saving by using the proposed method will be reported. The results show that less heat input will be required for the same amount of steam generation. The current study provides a theoretical support for waste heat recovery from the intercooler.

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Colorado Community Benefits From Installing Waste Heat Recovery System

ASME 2010 4th International Conference on Energy Sustainability, Volume 1 ◽

10.1115/es2010-90479 ◽

2010 ◽

Author(s):

Jennifer Strehler ◽

Scott Vandenburgh ◽

Dave Parry ◽

Tim Rynders

Keyword(s):

Natural Gas ◽

Heat Pump ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Waste Heat ◽

Electric Utility ◽

Treated Wastewater ◽

Waste Heat Recovery System ◽

Recovery System ◽

Heat Recovery System

The Town of Avon Colorado and the Eagle River Water and Sanitation District have partnered to design, construct, and operate a mechanical “Community Heat Recovery System” which extracts low-grade waste heat from treated wastewater and delivers this heat for beneficial use. Immediate uses include heating of the community swimming pool, melting snow and ice on high pedestrian areas in an urban redevelopment zone in order to improve pedestrian safety, and space heating for project buildings and an adjacent water plant pump station building. Points of use are located within one mile of the treatment plant. The initial system is sized to extract heat from 170 m3/hr (1.08 mgd) of wastewater plant effluent with a 298 kW (400 hp) heat pump. The heat pump will deliver 1,026 kW (3,500,000 BTU/hr) energy to the heat recovery system. A supplemental natural gas boiler provided to meet peak demands will provide an additional 1,026 kW (3,500,000 BTU/hr) energy. The system is expandable allowing the installation of a second heat pump in the future and roof-mounted solar thermal panels. Power for the waste heat recovery system is provided by wind-generated electricity purchased from the local electric utility. The use of wind power with an electric-powered heat pump enables the agencies to fulfill energy needs while also reducing the carbon footprint. The system will achieve a reduction in the temperature of the treated wastewater, which is currently discharged to the Eagle River during low river flow, fish-sensitive periods. The agencies expect to save tax payers and rate payers money as a result of this project as compared to other alternatives or the status quo because it results in a more sustainable long-term operation. At 2008 utility commodities pricing, delivery of heat generated from this system was estimated to cost about one-third less than that from a conventional natural gas boiler system. This facility is the first of its kind in the U.S. and received a “New Energy Community” grant from the State of Colorado. This project shows how local agencies can work cooperatively for mutual benefit to provide infrastructure which accommodates growth and urban renewal and simultaneously demonstrate strong environmental leadership. The potential application of this technology is broad and global. The installed system is expected to cost about $5,000,000; construction will be completed in 2010.

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