Treatment and re-use of raw blackwater by Chlorella vulgaris-based system

Segovia Bifarini, Marco Antonio (author), Žitnik, Miha (author), Griessler Bulc, Tjaša (author), Krivograd-Klemenčič, Aleksandra (author)

In this study, we examined a Chlorella vulgaris-based system as a potential solution to change liquid waste, such as blackwater, into valuable products for agriculture while protecting waters from pollution without technical demanding pre-treatment. To evaluate the possibility of nutrient removal and biomass production from raw blackwater, four blackwater dilutions were tested at lab-scale: 50%, 30%, 20%, and 10%. The results showed that even the less diluted raw blackwater was a suitable growth medium for microalgae C. vulgaris. As expected, the optimum conditions were observed in 10% blackwater with the highest growth rate (0.265 d$^{−1}$) and a nutrient removal efficiency of 99.6% for ammonium and 33.7% for phosphate. However, the highest biomass productivity (5.581 mg chlorophyll-a L$^{−1}$ d$^{−1}$) and total biomass (332.82 mg dry weight L$^{−1}$) were achieved in 50% blackwater together with the highest chemical oxygen demand removal (81%) as a result of the highest nutrient content and thus prolonged growth phase. The results suggested that the dilution factor of 0.5 followed by microalgae cultivation with a hydraulic retention time of 14 days could offer the highest biomass production for the potential use in agriculture and, in parallel, a way to treat raw blackwater from source-separation sanitation systems.

• Language: English
• Keywords: feces, urine, wastewater treatment, nutrients, biomass, agriculture
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: ZF - Faculty of Health Sciences; FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 17 str.
• Numbering: Vol. 12, iss. 10, art. 2660
• PID: 20.500.12556/RUL-125087
• UDC: 628.3
• ISSN on article: 2073-4441
• DOI: 10.3390/w12102660
• COBISS.SI-ID: 30855683
• Publication date in RUL: 04.03.2021

Record is a part of a journal

• Title: Water
• Shortened title: Water
• Publisher: Molecular Diversity Preservation International - MDPI
• ISSN: 2073-4441
• COBISS.SI-ID: 36731653

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.10.2020

Secondary language

• Language: Slovenian
• Keywords: fekalije, urin, čiščenje odpadnih voda, hranila, biomasa, kmetijstvo