Simple systems to characterize wastewaters - the case of biomethane potential

When the design or operation of wastewater treatment plans is considered, it is important to measure the polluting loads to be treated. These loads are calculated as the product of a daily volume of liquid waste and the average concentration of the pollutant. Of course, to do this, the sample must correctly represent the liquid effluent. Extensive analytical equipment can be used to characterize the numerous compounds contained within wastewaters with high accuracy but cheap, simple, and even sometimes mobile equipment are mostly used for the daily operations of treatment plans. In this regard, we present the use of a pH-respirometer, based on manometric methods, to characterize wastewaters that will be treated by aerobic biological systems. Another type of biological treatment system is based on anaerobic processes when the effluents have a high content of biodegradable organic compounds. Anaerobic digestion is very attractive as it is possible to produce a valuable gas (biogas) out of the waste instead of consuming energy and oxygen to realize an aerobic treatment. In this paper, we will present the meaning of biochemical methane potential (BMP) curves and compare those curves to respirometric curves such as biological oxygen demand (BOD) tests.