The paper evaluates the question of whether a combined anaerobic-aerobic or a solely aerobic treatment of some particular industrial wastewaters leads to better results. Therefore three different industrial wastewaters were treated in two different process lines: one line consisted of anaerobic treatment prior to aerobic treatment and in the other, only aerobic treatment was applied. The experiments were run with wastewater from:
the pectin industry
the sugar industry (beet sugar)
the animal pulp industry.
The data presented in this paper were gained from experimental work which was conducted over a period of two years. Different scales of treatment plants were used. The anaerobic treatment was done in full- and semitechnical scale reactors, while the aerobic treatment took place in labscale and semitechnical scale plants.
Surprisingly in all three cases the solely aerobic treatment led to slightly better results in terms of residual pollution.
Finally the paper presents data gained from a recently built, full-scale anaerobic-aerobic process which treats pectin waste. The aerobic stage of the process was designed on the basis of the results from the experimental work which was mentioned above. The results from the former experimental work and from the full-scale operation are compared.