PHOSPHORUS REMOVAL IN FILTERS FILLED WITH LWA MADE OF FLY ASHES

The effectiveness of phosphorus removal in vertical-flow filters with double-layer filling composed of light weight aggregate made of fly ashes from sewage sludge thermal treatment (FASSTT LWA) and gravel was determined. Synthetic wastewaters containing 7.36 mg/L of phosphorus were fed into filter columns filled with gravel and FASSTT LWA (gravel was the bed’s lower layer, whereas the top layer of the FASSTT LWA constituted 0, 12, 25, 50, and 100% of the depth of the column) at hydraulic loads from 0.003, to 0.007 m/d. The study demonstrated that the efficiency of phosphorus removal depends on the ratio between the gravel and FASSTT LWA. Phosphorus removal is mainly due to adsorption on the surface of the filter filling. The highest phosphorus removal rate was achieved in the filter column with 50% FASSTT LWA and 50% gravel content, irrespective of the hydraulic load applied. The study confirmed the possibility of using FASSTT LWA to produce granular filling and application as the filling of filter columns used for the treatment of wastewaters containing significant concentration of phosphorus.

[1]  L. Johansson.  The use of Leca (Light Expanded Clay Aggregates) for the removal of phosphorus from wastewater , 1997 .

[2]  L. W. Apperley,et al.  Removal of phosphorus from secondary effluent by a matrix filter , 1996 .

[3]  Lei Wang,et al.  Characteristics and mechanisms of phosphate adsorption on dewatered alum sludge , 2006 .

[4]  Anna Baryła,et al.  WYBÓR MATERIAŁU REAKTYWNEGO DO USUWANIA FOSFORU Z WÓD I ŚCIEKÓW NA PRZYKŁADZIE KRUSZYWA POPIOŁOPORYTOWEGO POLLYTAG , 2014 .

[5]  C. Mant,et al.  A feasibility study of a Salix viminalis gravel hydroponic system to renovate primary settled wastewater. , 2003, Bioresource technology.

[6]  K. C. Cheung,et al.  Improving phosphate removal of sand infiltration system using alkaline fly ash. , 2000, Chemosphere.

[7]  Tore Krogstad,et al.  Plant-availability of phosphorus in filter substrates derived from small-scale wastewater treatment systems , 2004 .

[8]  Dong-Cheol Seo,et al.  Evaluation of 2- and 3-stage combinations of vertical and horizontal flow constructed wetlands for treating greenhouse wastewater , 2008 .

[9]  Tõnu Mauring,et al.  Schoolhouse wastewater purification in a LWA-filled hybrid constructed wetland in Estonia , 2007 .

[10]  S. Kennedy,et al.  Dewatered alum sludge: a potential adsorbent for phosphorus removal. , 2006, Water Science and Technology.

[11]  H. Kong,et al.  Treatment Efficiencies of Constructed Wetlands for Eutrophic Landscape River Water * * Project suppo , 2007 .

[12]  H Brix,et al.  Phosphorus removal by sands for use as media in subsurface flow constructed reed beds. , 2001, Water research.

[13]  A. Albuquerque,et al.  Influence of bed media characteristics on ammonia and nitrate removal in shallow horizontal subsurface flow constructed wetlands. , 2009, Bioresource technology.

[14]  S. Vigneswaran,et al.  Adsorption of phosphorus in saturated slag media columns , 1997 .

[15]  C. Polprasert,et al.  Roles of oyster shells in an integrated constructed wetland system designed for P removal , 2008 .

[16]  R. Haverkamp,et al.  Phosphorus removal by an 'active' slag filter-a decade of full scale experience. , 2006, Water research.

[17]  J. Werther,et al.  Sewage sludge combustion , 1999 .

[18]  W. Park.  Integrated constructed wetland systems employing alum sludge and oyster shells as filter media for P removal , 2009 .

[19]  James L. Barnard,et al.  Nutrient Removal Technology in North America and the European Union: A Review , 2006 .

[20]  Vassilios A. Tsihrintzis,et al.  Effect of temperature, HRT, vegetation and porous media on removal efficiency of pilot-scale horizontal subsurface flow constructed wetlands , 2007 .

[21]  A. Edwards,et al.  Linking phosphorus sources to impacts in different types of water body , 2007 .

[22]  P. Randerson,et al.  Nitrogen removal from wastewater in vertical flow constructed wetlands containing LWA/gravel layers and reed vegetation , 2011 .

[23]  K. Sakadevan,et al.  Phosphate adsorption characteristics of soils, slags and zeolite to be used as substrates in constructed wetland systems , 1998 .