TY - JOUR
T1 - Pyrolysed powdered mussel shells for eutrophication control: effect of particle size and powder concentration on the mechanism and extent of phosphate removal
AU - Abeynaike, Arjan
AU - Wang, Luyao
AU - Jones, Mark I
AU - Patterson, Darrell A
PY - 2011
Y1 - 2011
N2 - The international shellfish farming industry has a growing problem with respect to sustainability: the shells, a by-product, are currently being mostly wasted to landfill. Instead, this calcium-rich resource can be used to produce lime [calcium oxide (CaO)] and then used to remove phosphate from rural wastewaters. Powdered mussel shell was heat treated to form lime. Two different shell particle sizes (fine, 53–106 µm; coarse, 212–250 µm) as well as various pyrolysis times, heating rates, pyrolysis temperatures and shell concentrations were used to determine the effects of these parameters on the lime formation and subsequent phosphate removal from a synthetic wastewater. Furthermore, the mechanisms of phosphate removal were determined by quantifying the phosphate content in all components before and after reaction with the synthetic wastewater. It was found that with excess of partially calcined pyrolysed shells, at a concentration of 5 g l−1, more than 95% phosphate removal was achieved, irrespective of particle size or pyrolysis conditions. When using optimally heat-treated shells (particle size: 53–106 µm, pyrolysed for 1 h at 750 °C), it was possible to achieve over 90% phosphate removal using just 196 mg l−1 of shell. For the pyrolysed shells, the main mechanisms of phosphate removal were homogeneous nucleation to form a suspended precipitate, as well as adsorption and heterogeneous precipitation on the surface of the remaining calcite shell particles
AB - The international shellfish farming industry has a growing problem with respect to sustainability: the shells, a by-product, are currently being mostly wasted to landfill. Instead, this calcium-rich resource can be used to produce lime [calcium oxide (CaO)] and then used to remove phosphate from rural wastewaters. Powdered mussel shell was heat treated to form lime. Two different shell particle sizes (fine, 53–106 µm; coarse, 212–250 µm) as well as various pyrolysis times, heating rates, pyrolysis temperatures and shell concentrations were used to determine the effects of these parameters on the lime formation and subsequent phosphate removal from a synthetic wastewater. Furthermore, the mechanisms of phosphate removal were determined by quantifying the phosphate content in all components before and after reaction with the synthetic wastewater. It was found that with excess of partially calcined pyrolysed shells, at a concentration of 5 g l−1, more than 95% phosphate removal was achieved, irrespective of particle size or pyrolysis conditions. When using optimally heat-treated shells (particle size: 53–106 µm, pyrolysed for 1 h at 750 °C), it was possible to achieve over 90% phosphate removal using just 196 mg l−1 of shell. For the pyrolysed shells, the main mechanisms of phosphate removal were homogeneous nucleation to form a suspended precipitate, as well as adsorption and heterogeneous precipitation on the surface of the remaining calcite shell particles
UR - http://www.scopus.com/inward/record.url?scp=79953718470&partnerID=8YFLogxK
UR - http://dx.doi.org/10.1002/apj.426
U2 - 10.1002/apj.426
DO - 10.1002/apj.426
M3 - Article
SN - 1932-2135
VL - 6
SP - 231
EP - 243
JO - Asia-Pacific Journal of Chemical Engineering
JF - Asia-Pacific Journal of Chemical Engineering
IS - 2
ER -