Removal of micropollutants from grey water : combining biological and physical/chemical processes

L. Hernandez Leal

Research output: Thesisinternal PhD, WUAcademic

Abstract

Grey water consists of the discharges from kitchen sinks, showers, baths, washing machines and hand basins. The amount of grey water produced per person in The Netherlands is about 90 Ld-1, accounting for up to 75 % of the wastewater volume produced by households, and over 90 % if vacuum toilets are installed. Grey water is relatively low in pollution and therefore, after appropriate treatment, has great potential for reuse in non-potable applications such as infiltration, irrigation, toilet flushing, laundry water, etc. The goal of this thesis was to develop a treatment concept for grey water to exploit its reuse potential. A special focus of this thesis was set on the study of organic micropollutants from personal care and household chemicals. Grey water (from 32 houses in Sneek, The Netherlands) contains, on average, 724-150 mgL-1 of chemical oxygen demand (COD), 27-12 mgL-1 of total nitrogen, 7.2-4.2 mgL-1 of phosphorus and 41-12 mgL-1 of anionic surfactants. The high biodegradability of grey water (70-5 %) indicated the possibility of recovering COD as methane. Biological treatment of grey water was conducted in three systems, aerobic, anaerobic and combined anaerobic + aerobic, at a total hydraulic retention time (HRT) of 12-13 hours at 32 °C. Aerobic treatment in a sequencing batch reactor resulted in COD removal of 90 %, which was significantly higher than 51 % removal by anaerobic treatment in an upflow anaerobic sludge blanket (UASB) reactor. Grey water treatment in a combined anaerobic + aerobic system resulted in a COD removal efficiency of 89 %. The application of a UASB reactor for the pre-treatment of grey water yielded a small amount of energy. Therefore, the aerobic system was preferred for grey water treatment. Bioflocculation of grey water in a high loaded membrane bioreactor was tested as alternative to aerobic treatment. The concentrated grey water of this process can potentially increase the methane yield by 73 % within ‘new sanitation' concepts. Eighteen compounds of personal care products and household chemicals (UV- filters, fragrances, preservatives, biocides, surfactants) were measured in grey water at low gL-1 levels. During biological treatment most of these compounds were partially removed. In general, the treatment in the aerobic system lead to the highest removal efficiencies of these compounds, where biodegradation and adsorption to sludge were the most likely removal mechanisms. However, the UV-filters PBSA and EHMC and the fragrance tonalide were poorly removed in the tested biological systems. Although reuse standards for these compounds do not exist, the post-reatment of aerobically treated effluent was recommended prior to reuse. Adsorption on activated carbon and ozonation were proven effective as post-treatment options for grey water.
LanguageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • Wageningen University
Supervisors/Advisors
  • Buisman, Cees, Promotor
  • Zeeman, Grietje, Co-promotor
  • Temmink, Hardy, Co-promotor
Award date10 Sep 2010
Place of Publication[S.l.
Publisher
Print ISBNs9789085857013
Publication statusPublished - 2010

Fingerprint

chemical process
water
chemical oxygen demand
sludge
removal
micropollutant
surfactant
water treatment
methane
filter
adsorption
preservative
sanitation
flushing
bioreactor
activated carbon
biodegradation
infiltration
pesticide
irrigation

Keywords

  • waste water treatment
  • pollutants
  • biodegradation
  • anaerobic digestion
  • biochemical oxygen demand
  • chemical oxygen demand
  • flocculation
  • disinfection
  • new sanitation

Cite this

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title = "Removal of micropollutants from grey water : combining biological and physical/chemical processes",
abstract = "Grey water consists of the discharges from kitchen sinks, showers, baths, washing machines and hand basins. The amount of grey water produced per person in The Netherlands is about 90 Ld-1, accounting for up to 75 {\%} of the wastewater volume produced by households, and over 90 {\%} if vacuum toilets are installed. Grey water is relatively low in pollution and therefore, after appropriate treatment, has great potential for reuse in non-potable applications such as infiltration, irrigation, toilet flushing, laundry water, etc. The goal of this thesis was to develop a treatment concept for grey water to exploit its reuse potential. A special focus of this thesis was set on the study of organic micropollutants from personal care and household chemicals. Grey water (from 32 houses in Sneek, The Netherlands) contains, on average, 724-150 mgL-1 of chemical oxygen demand (COD), 27-12 mgL-1 of total nitrogen, 7.2-4.2 mgL-1 of phosphorus and 41-12 mgL-1 of anionic surfactants. The high biodegradability of grey water (70-5 {\%}) indicated the possibility of recovering COD as methane. Biological treatment of grey water was conducted in three systems, aerobic, anaerobic and combined anaerobic + aerobic, at a total hydraulic retention time (HRT) of 12-13 hours at 32 °C. Aerobic treatment in a sequencing batch reactor resulted in COD removal of 90 {\%}, which was significantly higher than 51 {\%} removal by anaerobic treatment in an upflow anaerobic sludge blanket (UASB) reactor. Grey water treatment in a combined anaerobic + aerobic system resulted in a COD removal efficiency of 89 {\%}. The application of a UASB reactor for the pre-treatment of grey water yielded a small amount of energy. Therefore, the aerobic system was preferred for grey water treatment. Bioflocculation of grey water in a high loaded membrane bioreactor was tested as alternative to aerobic treatment. The concentrated grey water of this process can potentially increase the methane yield by 73 {\%} within ‘new sanitation' concepts. Eighteen compounds of personal care products and household chemicals (UV- filters, fragrances, preservatives, biocides, surfactants) were measured in grey water at low gL-1 levels. During biological treatment most of these compounds were partially removed. In general, the treatment in the aerobic system lead to the highest removal efficiencies of these compounds, where biodegradation and adsorption to sludge were the most likely removal mechanisms. However, the UV-filters PBSA and EHMC and the fragrance tonalide were poorly removed in the tested biological systems. Although reuse standards for these compounds do not exist, the post-reatment of aerobically treated effluent was recommended prior to reuse. Adsorption on activated carbon and ozonation were proven effective as post-treatment options for grey water.",
keywords = "afvalwaterbehandeling, verontreinigende stoffen, biodegradatie, ana{\"e}robe afbraak, biochemisch zuurstofverbruik, chemisch zuurstofverbruik, uitvlokking, desinfectie, nieuwe sanitatie, waste water treatment, pollutants, biodegradation, anaerobic digestion, biochemical oxygen demand, chemical oxygen demand, flocculation, disinfection, new sanitation",
author = "{Hernandez Leal}, L.",
note = "WU thesis 4865",
year = "2010",
language = "English",
isbn = "9789085857013",
publisher = "S.n.",
school = "Wageningen University",

}

Hernandez Leal, L 2010, 'Removal of micropollutants from grey water : combining biological and physical/chemical processes', Doctor of Philosophy, Wageningen University, [S.l..

Removal of micropollutants from grey water : combining biological and physical/chemical processes. / Hernandez Leal, L.

[S.l. : S.n., 2010. 181 p.

Research output: Thesisinternal PhD, WUAcademic

TY - THES

T1 - Removal of micropollutants from grey water : combining biological and physical/chemical processes

AU - Hernandez Leal, L.

N1 - WU thesis 4865

PY - 2010

Y1 - 2010

N2 - Grey water consists of the discharges from kitchen sinks, showers, baths, washing machines and hand basins. The amount of grey water produced per person in The Netherlands is about 90 Ld-1, accounting for up to 75 % of the wastewater volume produced by households, and over 90 % if vacuum toilets are installed. Grey water is relatively low in pollution and therefore, after appropriate treatment, has great potential for reuse in non-potable applications such as infiltration, irrigation, toilet flushing, laundry water, etc. The goal of this thesis was to develop a treatment concept for grey water to exploit its reuse potential. A special focus of this thesis was set on the study of organic micropollutants from personal care and household chemicals. Grey water (from 32 houses in Sneek, The Netherlands) contains, on average, 724-150 mgL-1 of chemical oxygen demand (COD), 27-12 mgL-1 of total nitrogen, 7.2-4.2 mgL-1 of phosphorus and 41-12 mgL-1 of anionic surfactants. The high biodegradability of grey water (70-5 %) indicated the possibility of recovering COD as methane. Biological treatment of grey water was conducted in three systems, aerobic, anaerobic and combined anaerobic + aerobic, at a total hydraulic retention time (HRT) of 12-13 hours at 32 °C. Aerobic treatment in a sequencing batch reactor resulted in COD removal of 90 %, which was significantly higher than 51 % removal by anaerobic treatment in an upflow anaerobic sludge blanket (UASB) reactor. Grey water treatment in a combined anaerobic + aerobic system resulted in a COD removal efficiency of 89 %. The application of a UASB reactor for the pre-treatment of grey water yielded a small amount of energy. Therefore, the aerobic system was preferred for grey water treatment. Bioflocculation of grey water in a high loaded membrane bioreactor was tested as alternative to aerobic treatment. The concentrated grey water of this process can potentially increase the methane yield by 73 % within ‘new sanitation' concepts. Eighteen compounds of personal care products and household chemicals (UV- filters, fragrances, preservatives, biocides, surfactants) were measured in grey water at low gL-1 levels. During biological treatment most of these compounds were partially removed. In general, the treatment in the aerobic system lead to the highest removal efficiencies of these compounds, where biodegradation and adsorption to sludge were the most likely removal mechanisms. However, the UV-filters PBSA and EHMC and the fragrance tonalide were poorly removed in the tested biological systems. Although reuse standards for these compounds do not exist, the post-reatment of aerobically treated effluent was recommended prior to reuse. Adsorption on activated carbon and ozonation were proven effective as post-treatment options for grey water.

AB - Grey water consists of the discharges from kitchen sinks, showers, baths, washing machines and hand basins. The amount of grey water produced per person in The Netherlands is about 90 Ld-1, accounting for up to 75 % of the wastewater volume produced by households, and over 90 % if vacuum toilets are installed. Grey water is relatively low in pollution and therefore, after appropriate treatment, has great potential for reuse in non-potable applications such as infiltration, irrigation, toilet flushing, laundry water, etc. The goal of this thesis was to develop a treatment concept for grey water to exploit its reuse potential. A special focus of this thesis was set on the study of organic micropollutants from personal care and household chemicals. Grey water (from 32 houses in Sneek, The Netherlands) contains, on average, 724-150 mgL-1 of chemical oxygen demand (COD), 27-12 mgL-1 of total nitrogen, 7.2-4.2 mgL-1 of phosphorus and 41-12 mgL-1 of anionic surfactants. The high biodegradability of grey water (70-5 %) indicated the possibility of recovering COD as methane. Biological treatment of grey water was conducted in three systems, aerobic, anaerobic and combined anaerobic + aerobic, at a total hydraulic retention time (HRT) of 12-13 hours at 32 °C. Aerobic treatment in a sequencing batch reactor resulted in COD removal of 90 %, which was significantly higher than 51 % removal by anaerobic treatment in an upflow anaerobic sludge blanket (UASB) reactor. Grey water treatment in a combined anaerobic + aerobic system resulted in a COD removal efficiency of 89 %. The application of a UASB reactor for the pre-treatment of grey water yielded a small amount of energy. Therefore, the aerobic system was preferred for grey water treatment. Bioflocculation of grey water in a high loaded membrane bioreactor was tested as alternative to aerobic treatment. The concentrated grey water of this process can potentially increase the methane yield by 73 % within ‘new sanitation' concepts. Eighteen compounds of personal care products and household chemicals (UV- filters, fragrances, preservatives, biocides, surfactants) were measured in grey water at low gL-1 levels. During biological treatment most of these compounds were partially removed. In general, the treatment in the aerobic system lead to the highest removal efficiencies of these compounds, where biodegradation and adsorption to sludge were the most likely removal mechanisms. However, the UV-filters PBSA and EHMC and the fragrance tonalide were poorly removed in the tested biological systems. Although reuse standards for these compounds do not exist, the post-reatment of aerobically treated effluent was recommended prior to reuse. Adsorption on activated carbon and ozonation were proven effective as post-treatment options for grey water.

KW - afvalwaterbehandeling

KW - verontreinigende stoffen

KW - biodegradatie

KW - anaërobe afbraak

KW - biochemisch zuurstofverbruik

KW - chemisch zuurstofverbruik

KW - uitvlokking

KW - desinfectie

KW - nieuwe sanitatie

KW - waste water treatment

KW - pollutants

KW - biodegradation

KW - anaerobic digestion

KW - biochemical oxygen demand

KW - chemical oxygen demand

KW - flocculation

KW - disinfection

KW - new sanitation

M3 - internal PhD, WU

SN - 9789085857013

PB - S.n.

CY - [S.l.

ER -