References
   -  LBS Protocol, United Nations Environment Program:
    Mediterranean Action Plan – Barcelona Convention and its
    Protocols, 1996. Available at: https://web.unep.org/unepmap/4-
    lbs-protocol-and-amendments (accessed March 13, 2020) 
-  Official Journal of the People’s Democratic Republic of Algeria,
    Executive Decree No. 06–141 of April 19, 2006. 
-  Official Journal of the People’s Democratic Republic of Algeria,
    Executive Decree No. 93–160 of 10 July 1993. 
-  ONA, Operating Instructions for the Guelma WWTP, ONA
    Report, National Sanitation Office, 2019. 
-  M. Belhani, R.A. Boufas, H. Boutaghan, F. Boudjahem, Life
    Cycle Assessment of Sludge Disposal of Wastewater Treatment
    Plant of Guelma City - Algeria, International Conference on
    Sustainable Water Treatment Technologies and Environment
    SUST_WATER2019, UDES, Algeria, 2019. 
-  R.H.C. Emmerson, G.K. Morse, J.N. Lester, D.R. Edge, The lifecycle
    analysis of small-scale sewage-treatment processes, Water
    Environ. J., 9 (1995) 317–325. 
-  P.J. Roeleved, A. Klapwijik, P.G. Eggels, W.H. Rulkens, W. van
    Starkenburg, Sustainability of municipal wastewater treatment,
    Water Sci. Technol., 35 (1997) 221–228. 
-  International Standard Organization ISO 14040, Environmental
    Management—Life Cycle Assessment: Principles and
    Framework, International Organization for Standardization,
    Geneva, 2006. 
-  International Standard Organization (ISO) 14044, Environmental
    Management—Life Cycle Assessment: Requirements and
    Guidelines, International Organization for Standardization,
    Geneva, 2006. 
-  H. Lin, X. Ma, Simulation of co-incineration of sewage sludge
    with municipal solid waste in a grate furnace incinerator,
    J. Waste Manage., 32 (2012) 561–567. 
-  Pré Consultants, GEMIS 4.9, Life Cycle Assessment Software
    Package, Global Emission Model for Integrated Systems,
    Version 4.9, Öko-Institut, 2019. Available at: http://iinas.org 
-  Ministry of Energy, Algeria’s Electricity and Gas Production
    Bulletin, 2019. 
-  WB, World Development Indicators: Electricity Production,
    Sources, and Access, 2019. Available at: http://wdi.worldbank.
    org/tables (accessed December 04, 2019) 
-  Y.Y.J. Shu, Elaboration D’un Guide Pour L’amélioration et
    L’évaluation de la Qualité D’inventaire de l’ACV, Application
    aux Filières de Traitement des Eaux Usée Usées Urbaines,
    Thesis Dissertation, 2002, pp. 168. 
-  A.M. Tillman, M. Svingby, H. Lundström, Life cycle assessment
    of municipal waste water systems, Int. J. Life Cycle Assess.,
    3 (1998) 145–157. 
-  S.R. Smith, Agricultural Recycling of Sewage Sludge and the
    Environment, CAB International, Wallingford, 1996, pp. 382. 
-  M. Henze, P. Harremoës, J.C. Jansen, E. Arvin, Wastewater
    Treatment, Biological and Chemical Processes, 3rd ed., Springer-
    Verlag, Berlin, Heidelberg, 2002. 
-  M. Bengtsson, M. Lundin, S. Molanderb, Life Cycle Assessment
    of Wastewater Systems - Case Studies of Conventional
    Wastewater Treatment, Using Sorting and Liquid Composting
    in Three Swedish Municipalities, Technical Environmental
    Planning Report, Chalmers University of Technology, 1997. 
-  E. Paul, M.L. Laval, M. Spérandio, Excess sludge production
    and costs due to phosphorus removal, Environ. Technol.,
    22 (2001) 1363–1371. 
-  G. Houillon, O. Jolliet, Life cycle assessment of processes for
    the treatment of wastewater urban sludge: energy and global
    warming analysis, J. Cleaner Prod., 13 (2005) 287–299. 
-  A. Hospido, T. Moreira, M. Martin, M. Rigola, G. Feijoo,
    Environmental evaluation of different treatment processes for
    sludge from urban wastewater treatments: anaerobic digestion
    versus thermal processes, Int. J. Life Cycle Assess., 10 (2005)
    336–345. 
-  P. Tidåker, E. Kärrman, A. Baky, H. Jönsson, Wastewater
    management integrated with farming – an environmental
    systems analysis of a Swedish country town, Resour. Conserv.
    Recyl., 47 (2006) 295–315. 
-  NA 17671, Algerian Standard NA 17671: Fertilizers - Sludge
    from Urban Wastewater Treatment Works - Names and Specifications,
    2010. Available at: http://www.ainor.org (accessed
    July 31, 2020) 
-  S. Lassaux, R. Renzoni, A. Germain, Life cycle assessment of
    water from the pumping station to the wastewater treatment
    plant, Int. J. Life Cycle Assess., 12 (2007) 118–126. 
-  F.J. Dennison, A. Azapagic, R. Clift, J.S. Colbourne, Assessing
    management options for wastewater treatment works in the
    context of life cycle assessment, Water Sci. Technol., 38 (1998)
    23–30. 
-  Y.J. Suh, P. Rousseaux, An LCA of alternative wastewater
    sludge treatment scenarios, Resour. Conserv. Recyl., 35 (2002)
    191–200. 
-  Y. Cheng, S. Oleszek, K. Shiota, K. Oshita, M. Takaoka,
    Comparison of sewage sludge mono-incinerators: mass balance
    and distribution of heavy metals in step grate and fluidized
    bed incinerators, J. Waste Manage., 105 (2020) 575–585. 
-  J. Zhao, B. Li, X. Wei, Y. Zhang, T. Li, Slagging characteristics
    caused by alkali and alkaline earth metals during municipal
    solid waste and sewage sludge co-incineration, Energy,
    202 (2020) 117773, doi: 10.1016/j.energy.2020.117773. 
-  R. Frischknecht, N. Jungbluth, H.J. Althaus, G. Doka,
    R. Dones, T. Heck, S. Hellweg, R. Hischier, T. Nemecek,
    G. Rebitzer, M. Spielmann, The ecoinvent database: overview
    and methodological framework, Int. J. Life Cycle Assess.,
    10 (2005) 3–9. 
-  L. Corominas, J. Foley, J.S. Guest, A. Hospido, H.F. Larsen,
    S. Morera, A. Shaw, Life cycle assessment applied to wastewater
    treatment: state of the art, Water Res., 47 (2013) 5480–5492. 
-  L.L. Fang, B. Valverde-Pérez, A. Damgaard, B. Gy. Plosz,
    M. Rygaard, Life cycle assessment as development and decision
    support tool for wastewater resource recovery technology,
    Water Res., 88 (2016) 538–549. 
-  P. Gilbert, S. Alexander, P. Thornley, J. Brammer, Assessing
    economically viable carbon reductions for the production of
    ammonia from biomass gasification, J. Cleaner Prod., 64 (2014)
    581–589. 
-  H. Yoshida, M. ten Hoeve, T.H. Christensen, S. Bruun,
    L.S. Jensen, C. Scheutz, Life cycle assessment of sewage sludge
    management options including long-term impacts after land
    application, J. Cleaner Prod., 174 (2018) 538–547. 
-  K. Johansson, M. Perzon, M. Froling, A. Mossakowska,
    M. Svanstrom, Sewage sludge handling with phosphorus
    utilization−life cycle assessment of four alternatives, J. Cleaner
    Prod., 16 (2008) 135–151. 
-  C. Mukherjee, J. Denney, E.G. Mbonimpa, J. Slagley,
    R. Bhowmik, A review on municipal solid waste-to-energy
    trends in the USA, Renewable Sustainable Energy Rev.,
	  119 (2020) 109512, doi: 10.1016/j.rser.2019.109512.