Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Wet extraction of heavy metals and chloride from MSWI and straw combustion fly ashes

Journal Article · · Waste Management
 [1];  [2]
  1. Hamburg University of Technology, Institute of Environmental Technology and Energy Economics, Eissendorfer Street 40, D-21073 Hamburg (Germany)
  2. Vattenfall Research and Development AB, SE-814 26 Alvkarleby (Sweden)

Fly ash residues from combustion often do not meet the criteria neither for reuse as construction materials nor landfilling as non-hazardous waste, mainly because of the high concentration of heavy metals and chlorides. This work aimed to technically evaluate an innovative wet treatment process for the extraction of chloride (Cl{sup -}), cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) from fly ashes from a municipal solid waste incineration (MSWI) plant and from a straw combustion (SC) facility. Factors investigated were liquid/solid (L/S) ratio, full carbonation (CO{sub 2} treatment), influence of pH and leaching time, using a two-level full factorial design. The most significant factor for all responses was low pH, followed by L/S ratio. Multiple linear regression models describing the variation in extraction data had R{sup 2} values ranging from 58% to 98%. An optimization of the element extraction models was performed and a set of treatment conditions is suggested.

OSTI ID:
21269363
Journal Information:
Waste Management, Journal Name: Waste Management Journal Issue: 9 Vol. 29; ISSN WAMAE2; ISSN 0956-053X
Country of Publication:
United States
Language:
English