This study consisted of the construction and laboratory testing of a new ex
perimental biofilm reactor for the carbonaceous oxidation of a synthetic wa
stewater. The biofilm unit used in the reactor was constructed from corruga
ted plastic sheets in the form of a cube which was moved vertically, and wa
s alternately immersed in and lifted out of the wastewater. In the experime
ntal work, soluble chemical oxygen demand removal rates of 43 g CODs/m(2) d
or 3.8 kg CODs/m(3) d were achieved and these rates compare favourably wit
h other biofilm systems. The new biofilm experimental unit was simple to co
nstruct and operate, and was very effective in biologically treating the sy
nthetic wastewater used in the study. (C) 1999 Elsevier Science Ltd. All ri
ghts reserved.