Remediacija odpadnega blata iz čistilne naprave z uporabo EDTA in preverjanje parametrov za primernost uporabe remediranega blata kot gnojilnega sredstva

Vesnić, Tim (author), Leštan, Domen (mentor), Kaurin, Anela (co-mentor)

Odpadno blato iz čistilnih naprav (ČN) ima zaradi velike vsebnosti hranilnih snovi potencial za uporabo v kmetijstvu, pri čemer pa predstavlja težavo dejstvo, da pogosto vsebuje potencialno strupene kovine (PSK). Cilj te naloge je bil preveriti, ali uporaba EDTA (35 in 50 mmol L-1) skupaj z oksalno kislino (35, 50 in 100 mmol L-1) omogoča učinkovito odstranitev PSK iz odpadnega blata, po predhodni aerobni biološki obdelavi. Remediacijo odpadnega blata smo izvajali hkrati z anaerobno biološko obdelavo. Izvedeni so bili trije poskusi, dva preliminarna poskusa sta bila namenjena optimizaciji metod in izbiri materialov. Pri glavnem poskusu je bilo najučinkovitejše odstranjevanje pri obravnavanju z oksalno kislino (100 mmol L-1) in EDTA (50 mmol L-1). Povprečni delež odstranitve Pb je bil do 82,18 %, povprečni delež odstranitve Zn je bil 95,42 %, Fe do 97,18 %, Cu do 78,36 %, Mn do 93,61 % in Cr do 59,93 %. Pri glavnem poskusu so bile po remediaciji koncentracije v ekstraktih za vse PSK pod mejo za nenevarne snovi. Vsebnost hranil se po remediaciji ni znatno spremenila, razen pri tretiranju z oksalno kislino (100 mmol L-1) in EDTA (50 mmol L-1), ko se je totalni fosfor za 92,04 % zmanjšal.

• Language: Slovenian
• Keywords: čistilna naprava, etilendiamintetraocetna kislina, potencialno strupene kovine, remediacija, blato, aerobna biološka obdelava, anaerobna biološka obdelava
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Year: 2023
• PID: 20.500.12556/RUL-148045
• COBISS.SI-ID: 160040963
• Publication date in RUL: 26.07.2023

Secondary language

• Language: English
• Title: Remediation of waste sludge from the treatment plant using EDTA and verification of parameters for the suitability of the use of treated sludge as a fertilizer

Abstract

Sewage sludge from treatment plants (STP) has the potential for reuse in agriculture due to its high mineral nutrient content, but the presence of potentially toxic metals (PTM) is often a problem. The aim of this study was to check whether the use of EDTA (35 and 50 mmol L-1) together with oxalic acid (35, 50 and 100 mmol L-1), enables the effective removal of PTM from waste sludge after aerobic biological treatment. Remediation of waste sludge took place simultaneously with anaerobic biological treatment. Three experiments were carried out, two preliminary tests were intended to determine the best methods and materials for further experiments. In the main experiment, the most effective removal was when treated with oxalic acid (100 mmol L-1) and EDTA (50 mmol L-1). The average Pb removal rate was up to 82.18 %, the average Zn removal rate was 95.42 %, Fe up to 97.18 %, Cu up to 78.36 %, Mn up to 93.61 % and Cr up to 59.93 %. In the main experiment, the concentrations in the leachates after remediation were below the limit for non-hazardous substances for all PTM. The content of mineral nutrients did not change significantly after remediation, except when treated with oxalic acid (100 mmol L-1) and EDTA (50 mmol L-1), the total phosphorus decreased by 92.04 %.

• Keywords: sewage treatment plant, ethylenediaminetetraacetic acid, potentially toxic metals, remediation, sludge, aerobic biological treatment, anaerobic biological treatment