Reuse of Domestic Effluent

  • View
    216

  • Download
    0

Embed Size (px)

Transcript

  • UNIVERSIDADE FEDERAL DE SANTA CATARINACENTRO TECNOLGICO

    PROGRAMA DE PS-GRADUAO EM ENGENHARIA AMBIENTAL

    REUSE OF DOMESTIC EFFLUENT THROUGH PELETIZED DUCKWEEDS WITH RED TILAPIA

    FARMING

    Flvia Tavares, Dra. OEI consultant at MPA

    Rodrigo Roubach, PhDProject Manager/MPADigenes Lemainski

    OEI consultant at MPAFlvio Rubens Lapolli, Dr.

    UFSC

  • The reuse of the effluent from duckweed based pondsin fish farming

    It can reduce the environmental impact caused by the domestic wastewater treatment

    Produce high protein biomass

  • The present study aimed to evaluate the sustainability of duckweed-based-ponds as a tertiary

    treatment

    Considering pollutants removal

    And its use as a feed source in tilapia production

    Objectives

  • Wastewater Treatment Plant Florianpolis

    Reuse system

    Facultative pond I

    Anaerobic pond

    Facultative pond II

    Facultative pond III

    The effluent used in the Reuse System was pumped from the last Facultative Pond (Facultative pond III).

    Methodology

  • Duckweed-fish reuse pilot system

  • The Reuse System was composed by the duckweeds treatment and fish production tanks during a 83

    days trial

    Duckweeds treatment Fish production tanks

  • Effluent sampling and physical-chemical analysis from duckweeds and fish tanks were conducted weekly.

    Variables analyzed were: TAN (NH3 + NH4+), nitrite (NO2-), nitrate (NO3-), total nitrogen (TN), Chemical oxygen demand (COD), Biochemical oxygen demand (BOD), Suspended, total and fixed solids, Orthophosphate,

    Turbidity, and Total and Fecal coliforms

    Also, pH, alkalinity, conductivity, temperature, dissolved oxygen, and transparency were recorded weekly. All

    analyses followed APHA (1998) recommendations

  • .Fingerlings in each experimental unit were weighted every two weeks during experimental period for weight gain (final weight

    initial weight), feed conversion (total dry feed fed /total wet weight gain), and specific growth rate (100 x Ln final average

    weight Ln initial average weight/days) estimation.

  • Duckweed average production registered in the present study could reach up to 31.1 t/ha/year (dry matter), with a crude protein

    content of 39.9%.

  • The results obtained shown that duckweeds presented a satisfactory pollutants removal, mainly for Turbidity

    (54.5%), Suspended Solids (44.4%) and COD (39.4%), reaching adequate criteria for aquaculture (Nitrite, Nitrate

    and COD concentrations under acceptable levels).

    However, an increase in retention time could improve plant performance.

    Results

  • Table 1. Final Weight, Feed Conversion Rate and Specific Growth Rate comparison between fish fed peletized duckweed and commercial ration.

    VariableDiet P value

    Dried duckweed Commercial ration

    Final Weight (g) 25.9 a 32.06 a 0.0805

    Feed Conversion Rate 1.61

    a 1.59 a 0.2515

    Specific Growth Rate 5.28

    a 5.56 a 0.1459

    Considering tilapia growth performance, it was observed no statistical difference between tilapia fed on pelletized duckweed and commercial

    feed, as shown in Table 1.

    Results

  • According to our results, we can conclude that fish

    produced in the reuse system fed on pelletized duckweed

    reached an average productivity of 22.5 t/ha/cycle, allowing the production of two tilapia production cycles per

    year, similar to traditional systems.

    Conclusion

  • Thank you!...

    Rodrigo Roubach, PhDProject manager - MPA0 xx 61 3218.4895roubach@seap.gov.br

    Esplanada dos Ministrios, Bloco DCEP: 70.043-900 - Braslia/DF

    Telefones: (61) 3218-2872 / 2876Fax: (61) 3224-5049

    www.presidencia.gov.br/seap

    Fellowship andTravel sponsor

    Slide Number 1Slide Number 2Slide Number 3Slide Number 4Slide Number 5Slide Number 6Slide Number 7Slide Number 8Slide Number 9Slide Number 10Slide Number 11Slide Number 12Slide Number 13

Recommended

View more >