A holistic approach to the recovery of valuable substances from the treatment sludge formed from chemical precipitation of fruit processing industry wastewater.
Sci Total Environ
; 917: 170372, 2024 Mar 20.
Article
em En
| MEDLINE
| ID: mdl-38280603
ABSTRACT
In this study, recovery of phenolic substances with Soxhlet extraction, (SE) ultrasound-assisted extraction (UAS), and supercritical CO2 (SC-CO2) extraction methods from chemical sludge obtained with chemical precipitation (FeCl3/PACS, Ca(OH)2/PACS, perlite/PACS, FeCl3/cationic polyelectrolyte) of lemon processing wastewater was investigated. The effect of used coagulants/flocculants and pH on COD and total phenolic substance content (TPC) removal was researched. Recovered phenolic substance profiles were also determined with HPLC-DAD. Additionally, response surface methodology was used to determine optimum treatment conditions. ANOVA analysis showed that pH is a more important variable than coagulant/flocculant doses for all chemical precipitation experimental sets. The highest removal efficiencies for COD and TPC was obtained in FeCl3/PACS (COD 72.0 %, TPC 93.7 %). Optimum dose values were determined as pH 4, FeCl3 3000 mg/L, PACS 400 mg/L for FeCl3/PACS, pH 6.5, Ca(OH)2 1500 mg/L, PACS 300 mg/L for Ca(OH)2/PACS, pH 5.5, PACS 7000 mg/L, perlite 50 g/L for perlite/PACS, pH 4.5, FeCl3 500 mg/L, polyelectrolyte 4 mg/L for FeCl3/polyelectrolyte. TPC removal efficiencies were determined as 55 %, 35 %, 57 % and 58 % in these conditions, respectively. Maximum TPC in extracts was determined as 39.03 mg GAE/g extract, 8.81 mg GAE/g extract, and 4.34 mg GAE/g extract for SE, UAS, and SC-CO2, respectively. TPC recovery efficiencies (RTPC) for all chemical sludge were SE > UAS > SC-CO2. Additionally, the TPC profile has shown a difference depending on the extraction method. According to the results of this study, it was concluded that the coagulation-flocculation process may be a suitable alternative for fruit juice processing industry wastewater in terms of both reducing environmental pollution and recovering polyphenolics from formed sludge. Consequently, this study presented a different perspective on the recovery from wastes with valuable substance recovery from chemical sludge.
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Texto completo:
1
Base de dados:
MEDLINE
Medicinas Complementares:
Homeopatia
Métodos Terapêuticos e Terapias MTCI:
Terapias_biologicas
Assunto principal:
Esgotos
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Compostos Férricos
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Cloretos
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Dióxido de Silício
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Óxido de Alumínio
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Águas Residuárias
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2024
Tipo de documento:
Article