The development of anaerobic treatment and its future.

Anaerobic treatment is well over 100 years old. Its initial development was for the treatment of domestic wastewaters, using anaerobic filters and hybrid processes that are still of interest today. It then progressed in application to separate sludge digestion, then to treatment of dilute industrial wastewaters. Several processes have been developed that accomplish efficient treatment of wastewaters at short detention times. Major contributions to the broad application of anaerobic treatment and the better understanding of this process has come from efforts by G. Lettinga and his colleagues. They have emphasized its importance for meeting the need for sustainable development in the future. Greater efforts are now needed for broad application of anaerobic treatment for ridding the environment of unwanted organic materials by converting them into methane, a renewable energy source.