title: Wastewater and greywater reuse on irrigation in centralized and decentralized systems--an integrated approach on water quality, energy consumption and CO2 emissions.
abstract: Wastewater and greywater have different scales of end-uses in irrigation in Portugal. Wastewater is treated in a central wastewater treatment plant and reused in public/private large areas of irrigation, like agriculture, public gardens and golf courses. On the contrary, greywater reuse is generally applied in in situ small scales, treated and used in the same place, generally in the production site. The main aim of this paper is to compare the two types of systems: a wastewater centralized reuse system (WWCRS) and a greywater decentralized reuse system (GWDRS) in terms of water quality, energy consumption and CO2 emissions. In this paper, the main characteristics of both streams are presented and the degree of treatment required in each stream is analyzed. The advantages and disadvantages of its reuse in different scales, in terms of water quality, energy consumption and CO2 emissions are discussed. A methodology to calculate the energy consumptions and CO2 emissions related to wastewater treatment that may be applied in different cases is presented. A hypothetical example of the two systems: one referring to a WWCRS and the other to a GWDRS is presented. The energy consumption and the CO2 emissions are analyzed and compared. The WWCRS needs a higher degree of treatment and so it spends more energy and leads to more CO2 emissions to the environment than the GWDRS that consumed between 11.8 and 37.5% of the energy consumed in the WWCRS considering the same number of inhabitants served.
authors: Universidade de Trás-os-Montes e Alto Douro, Escola de Ciências e Tecnologia, 5000-801 Vila Real, Portugal; C-MADE - Centre of Materials and Building Technologies, University of Beira Interior, 6201-001 Covilhã, Portugal. Electronic address: crismato@utad.pt.
authors: C
authors: C
authors: Matos
authors: Universidade de Trás-os-Montes e Alto Douro, Escola de Ciências e Tecnologia, 5000-801 Vila Real, Portugal; C-MADE - Centre of Materials and Building Technologies, University of Beira Interior, 6201-001 Covilhã, Portugal.
authors: S
authors: S
authors: Pereira
authors: Universidade de Trás-os-Montes e Alto Douro, Escola de Ciências e Tecnologia, 5000-801 Vila Real, Portugal; INESC TEC (formerly INESC Porto), Rua Dr. Roberto Frias, 378, Porto 4200-465, Portugal.
authors: E V
authors: EV
authors: Amorim
authors: Universidade de Trás-os-Montes e Alto Douro, Escola de Ciências e Tecnologia, 5000-801 Vila Real, Portugal; C-MADE - Centre of Materials and Building Technologies, University of Beira Interior, 6201-001 Covilhã, Portugal.
authors: I
authors: I
authors: Bentes
authors: Universidade de Trás-os-Montes e Alto Douro, Escola de Ciências e Tecnologia, 5000-801 Vila Real, Portugal; C-MADE - Centre of Materials and Building Technologies, University of Beira Interior, 6201-001 Covilhã, Portugal.
authors: A
authors: A
authors: Briga-Sá
keywords: CO(2) emissions; Energy; Greywater; Irrigation; Reuse; Wastewater