Clean Technologies and Environmental Policy

, Volume 15, Issue 1, pp 185–197 | Cite as

Multi-objective optimization of process cogeneration systems with economic, environmental, and social tradeoffs

  • Hisham S. Bamufleh
  • José María Ponce-Ortega
  • Mahmoud M. El-Halwagi
Original Paper

Abstract

Process cogeneration is an effective strategy for exploiting the positive aspects of combined heat and power in the process industry. Traditionally, decisions for process cogeneration have been based mostly on economic criteria. With the growing interest in sustainability issues, there is need to consider economic, environmental, and social aspects of cogeneration. The objective of this article is to develop an optimization framework for the design of process cogeneration systems with economic, environmental, and social aspects. Process integration is used as the coordinating framework for the optimization formulation. First, heat integration is carried out to identify the heating utility requirements. Then, a multi-header steam system is designed and optimized for inlet steam characteristics and their impact on power, fixed and operating costs, greenhouse gas emissions, and jobs. A genetic algorithm is developed to solve the optimization problem. Multi-objective tradeoffs between the economic, environmental, and social aspects are studied through Pareto tradeoffs. A case study is solved to illustrate the applicability of the proposed procedure.

Keywords

Combined heat and power Energy integration Process integration Greenhouse gas emissions Optimization 

List of symbols

A

Constant for the turbine efficiency relationship

a0

Constant for the turbine efficiency

a1

Constant for the turbine efficiency

a2

Constant for the turbine efficiency

a3

Constant for the turbine efficiency

ae

Electrical power price

af

Unit fuel cost for fuel f

As

Constant for the saturation temperature correlation

B

Constant for the turbine efficiency relationship

Bs

Constant for the saturation temperature correlation

Cboiler

Cost for the boiler

Costa

Combustion air fan power cost

Costb

Sewer charges for boiler blowdown

Costd

Ash disposal cost

Coste

Environmental emissions control cost

CostBFW

Boiler feed water treatment cost

Costfuel

Fuel cost

Costg

Generation cost

Costm

Maintenance materials and labor cost

Costp

Feed water pumping power cost

Costw

Raw water supply cost

CTurbine

Cost for the turbine

fcP,v

Flowrate times heat capacity for cold process stream v

FCP,u

Flowrate times heat capacity for hot process stream u

Fp

Flexibility factor for the increase in pressure in the boiler

GHG

Greenhouse gas emissions

ghgef

Unit greenhouse gas emissions for fuel f

h

Enthalpy

h1

Enthalpy for the steam at the turbine inlet

ha2

Actual enthalpy for the steam at the outlet from the turbine

hf

Saturated fluid enthalpy

his2

Outlet isentropic enthalpy

HY

Hours per year that operates the plant

JOB

Total generated jobs

jobsf

Unit jobs for fuel f

kF

Factor used to annualize the capital costs

m

Steam flowrate

Mmax

Maximum flowrate in the turbine

NC

Total number of cold process streams

NH

Total number of hot process streams

Np

Factor for accounting for the operating pressure

NT

Factor accounting for the superheat temperature

P

Pressure

Pe

Electric power price

Pt

Turbine shaft power output

Pg1

Gauge pressure of the boiler

Qb

Heat load required in the boiler

Qf

Heat load for the combustion of fuel f supplied to the boiler

Qprocess

Heating requirement for the process streams

s

Entropy

T

Temperature

T1

Inlet temperature to the turbine

TAC

Total annual cost

Tsat

Saturation temperature

Tsat1

Saturation temperate for the steam inlet to the turbine

Tsat2

Saturation temperate for the steam at high pressure

Tsh

Superheat temperature

\( t_{v}^{\text{s}} \)

Temperature supplied for cold process stream v

\( T_{u}^{\text{s}} \)

Temperature supplied for hot process stream u

\( t_{v}^{\text{t}} \)

Target temperature for cold process stream v

\( T_{u}^{\text{t}} \)

Target temperature for hot process stream u

u

Hot process streams

v

Cold process streams

W

Work

Greek symbols

Δhis

Isentropic enthalpy difference in the turbine

ηf

Efficiency in the boiler for the fuel f

ηg

Generator efficiency

ηis

Isentropic efficiency for the turbine

ηis

Maximum efficiency in the turbine

ηturbine

Turbine efficiency

Conditions

1

Low pressure

2

High pressure

References

  1. Al-Azri N, Al-Thubaiti M, El-Halwagi MM (2009) An algorithmic approach to the optimization of process cogeneration. Clean Technol Environ Policy 11(3):329–338CrossRefGoogle Scholar
  2. Al-Sulaiman FA, Jamdullaphur F, Dincer I (2010) Trigeneration: a comprehensive review based on prime movers. Int J Energy Res 35(3):233–258CrossRefGoogle Scholar
  3. Branan C (2002) Rules of thumb for chemical engineers. Gulf Professional Publishing, HoustonGoogle Scholar
  4. Dhole VR, Linnhoff B (1992) Total site targets for fuel, co-generation, emissions, and cooling. Comput Chem Eng 17:S101–S109Google Scholar
  5. El-Halwagi MM (1997) Pollution prevention through process integration: systematic design tools. Academic Press, San DiegoGoogle Scholar
  6. El-Halwagi MM (2006) Process integration. Elsevier, AmsterdamGoogle Scholar
  7. El-Halwagi MM (2012) Sustainable design through process integration: fundamentals and applications to industrial pollution prevention, resource conservation, and profitability enhancement. Butterworth-Heinemann, LondonGoogle Scholar
  8. El-Halwagi MM, Harell D, Spriggs HD (2009) Targeting cogeneration and waste utilization through process integration. Appl Energy 86(6):880–887CrossRefGoogle Scholar
  9. Foo DCY (2009) State-of-the-art review of pinch analysis techniques for water network synthesis. Ind Eng Chem Res 48(11):5125–5159CrossRefGoogle Scholar
  10. IMPLAN (2012) Minnesota IMPLAN group. http://www.implan.com/. Accessed April 2012
  11. JEDI (2012) Job and economic development impact model. http://www.nrel.gov/analysis/jedi/. Accessed April 2012
  12. Kemp I (2009) Pinch analysis and process integration—a user guide on process integration for the efficient use of energy, 2nd edn. Butterworth-Heinemann, AmsterdamGoogle Scholar
  13. Klemes J, Dhole VR, Raissi K, Perry SJ, Puigjaner L (1997) Targeting and design methodology for reduction of fuel, power, and CO2 on total sites. Appl Therm Eng 17(8–10):993–1003CrossRefGoogle Scholar
  14. Kumana J (2003) How to calculate the true cost of steam, DOE/GO-102003-1736. US Department of Energy, WashingtonGoogle Scholar
  15. Mahmud R, Harell D, El-Halwagi MM (2012) A process integration framework for the optimal design of combined heat and power systems in the process industries, chapter 14. In: Foo DCY, El-Halwagi MM, Tan RR (eds) Recent advances in sustainable process design and optimization. Advances in process systems engineering. World Scientific Publishing Company, LondonGoogle Scholar
  16. Majozi T (2010) Batch chemical process integration: analysis, synthesis, and optimization. Springer, HeidelbergCrossRefGoogle Scholar
  17. Mavromatis SP (1996) Conceptual design and operation of industrial steam turbine networks, Ph.D. Thesis, University of Manchester Institute of Science and Technology, ManchesterGoogle Scholar
  18. Mavromatis SP, Kokossis AC (1998) Conceptual optimization of utility networks for operational variation-I targets and level optimization. Chem Eng Sci 53(8):1585–1608CrossRefGoogle Scholar
  19. Miller RE, Blair PD (2009) Input-output analysis: foundations and extensions. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  20. Mohan T, El-Halwagi MM (2007) An algebraic targeting approach for effective utilization of biomass in cogeneration systems through process integration. Clean Technol Environ Policy 9(1):13–25CrossRefGoogle Scholar
  21. Noureldin MB (2012) Pinch technology and beyond: new vistas on energy efficiency optimization. Nova Science Publishers, New YorkGoogle Scholar
  22. Raissi K (1994) Total site integration. Ph.D. Thesis, University of Manchester Institute of Science and Technology, Manchester, UKGoogle Scholar
  23. Rossiter AP (2010) Improve energy efficiency via heat integration. Chem Eng Prog 106(12):33–42Google Scholar
  24. Smith R (2005) Chemical process design and integration. Wiley, New YorkGoogle Scholar
  25. Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL (eds) (2007) Climate change: the physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change. Cambridge University Press, New YorkGoogle Scholar
  26. Tora EA, El-Halwagi MM (2011) Integrated conceptual design of solar-assisted trigeneration systems. Comput Chem Eng 35(9):1807–1814CrossRefGoogle Scholar
  27. Varbanov PS, Doyle S, Smith R (2004) Modelling and optimization of utility systems. Chem Eng Res Des 76(3):239–245Google Scholar
  28. Wu DW, Wang RZ (2006) Combined cooling, heating and power: a review. Prog Energy Combust Sci 32(5–6):459–495CrossRefGoogle Scholar
  29. You F, Tao L, Graziano DJ, Snyder SW (2012) Optimal design of sustainable cellulosic biofuel supply chains: multiobjective optimization coupled with life cycle assessment and input–output analysis. AIChE J 58(4):1157–1180CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Hisham S. Bamufleh
    • 1
  • José María Ponce-Ortega
    • 2
  • Mahmoud M. El-Halwagi
    • 1
    • 3
  1. 1.Chemical and Materials Engineering Department, Faculty of EngineeringKing Abdulaziz UniversityJeddahSaudi Arabia
  2. 2.Chemical Engineering DepartmentUniversidad Michoacana de San Nicolás de HidalgoMoreliaMexico
  3. 3.Chemical Engineering DepartmentTexas A&M UniversityCollege StationUSA

Personalised recommendations