Method and apparatus for measuring a function of the acute toxicity of flue sig

摘要

1492637 Testing water KALLEREGULATORER AB 4 April 1975 [4 April 1974] 13935/75 Heading G1B [Also in Division B1] A process for measuring the toxicity of an aqueous liquid to micro-organisms present in biological purification plants comprises preaerating at least a part of the liquid almost to oxygen saturation, contacting the preaerated liquid with a submerged biological bed and measuring the oxygen content in the at least part of the liquid after contact with the bed, the biomass of the bed being maintained at a substantially content level. The apparatus may comprise a preaerator 1 for the liquid flowing in at 2, a biological bed comprising at least a pair of opposed mutually movable surfaces defining channels therebetween, as in the embodiment shown between fixed baffles 7 and discs 6 mounted on rotatable shaft 14 and a device such as oxygen electrode 9 for the continuous or intermittent measurement of the oxygen content in the liquid after it has left the bed. Shaft 14 may be mounted for oscillatory movement to vary the distance between baffles 7 and discs 6 and hence the thickness of the biofilm which forms on the baffles and discs.