Stabilization of metal processing plant sludge via sequential application of phytoremediation and pyrolysis


ÖZKAN A., Çokaygil Z., BANAR M.

Toxicological and Environmental Chemistry, cilt.97, sa.8, ss.989-1002, 2015 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 97 Sayı: 8
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1080/02772248.2015.1093127
  • Dergi Adı: Toxicological and Environmental Chemistry
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.989-1002
  • Anahtar Kelimeler: hazardous waste, metal processing sludge, phytoremediation, pyrolysis, SEPARATING HEAVY-METALS, POTENTIAL VALORISATION, CONTAMINATED BIOMASS, SEWAGE-SLUDGE, PART II, BIO-OIL, TEMPERATURE, SOIL, HYPERACCUMULATORS, CADMIUM
  • Anadolu Üniversitesi Adresli: Evet

Özet

© 2015 Taylor & Francis.The aim of this study is to evaluate the metal removal ability of three different plants from metal processing sludge containing Pb, Cd, and Zn. Therefore, phytoremediation and pyrolysis were sequentially applied. In the phytoremediation applications, sunflower (Helianthus annuus), corn (Zea mays), and rape (Brassica napus) seeds were sown in sludge/soil mixtures at four different levels (25/75, 50/50, 75/25, 100/0). The chelating agent, ethylenediaminetetraacetic acid, was added to the mixtures for plant uptake during phytoremediation. At the phytoremediation stage, it was noted that rape was the most effective plant for the mixture of 75/25 sludge/soil, with metal removal efficiencies ranging between 80%–90%. At the pyrolysis stage, after harvesting, contaminated plants grown in a 75/25 sludge/soil mixture were pyrolyzed at 500 °C, with a heating rate of 35 °C/min. The results show that 60%–90% of the initial metal content was held by the solid product. In addition to this, it can be concluded that pyrolysis stabilizes metals into a solid product and that this solid product can be safely landfilled as inert waste since its toxicity leaching value is lower than the limit values.