Treatment of oil-in-water emulsions: performance of a sawdust bed filter.
The effect of operating conditions on the performance of a sawdust bed filter used for the treatment of an oil-in-water emulsion was investigated. A metalworking fluid (3 vol.% oil) was used as oil-in-water emulsion and sawdust as filter medium and sorbent. Because of the high stability of the emulsion, small amounts of inorganic salt (calcium sulphate) were mixed with the sorbent, acting as coagulant to achieve the emulsion breakdown. The influence of flow rate, bed height, temperature and the amount of coagulant salt added was studied. Experimental results show that several processes are involved in oil removal from oil-in-water emulsions, i.e. coagulation, coalescence, adsorption or straining. More than 99% of oil content in the influent stream was removed. Experimental results show that low-cost sorbents like sawdust are feasible to be used in the treatment of oil-in-water emulsions if small amounts of coagulant salts are added to the filter media.
Cambiella
Angel
A
Department of Chemical and Environmental Engineering, University of Oviedo, C/Julián Clavería 8, 33006 Oviedo, Spain.
Ortea
Enrique
E
Ríos
Guillermo
G
Benito
José M
JM
Pazos
Carmen
C
Coca
José
J
D000327:Adsorption; D004391:Dust; D004655:Emulsions / Q000737:chemistry; D005374:Filtration; D009821:Oils / Q000032:analysis*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014873:Water Pollutants / Q000032:analysis*
D004391:Dust; D004655:Emulsions; D009821:Oils; D014873:Water Pollutants