Influence of phosphorus, potassium, and copper on methane biofiltration performance

Abstract

In addition to a carbon source, bacteria require for growth a variety of nutrients such as phosphorus, potassium, and several other micronutrients including copper. The study described in this paper was conducted with the aim of determining the influence of phosphorus, potassium, and copper on methane elimination in a biofilter. The study revealed that the particular phosphorus concentration leading to the greatest methane elimination capacity, which was 44·7  g m−3 h−1 at a methane inlet load of 75  g m−3 h−1, was 3·1  g/L. The influence of the phosphorus concentration on the methane elimination capacities was also investigated for methane inlet loads of between 8 and 95  g m−3 h−1. The optimum range of the nitrogen  –  phosphorus mass ratios, determined during this study ranged from 0·5 to 2·5. It was established that, in comparison with phosphorus, potassium does not seem to be a determining element for the biological removal efficiency and does not significantly affect the microorganisms’ behaviour. However, a concentration of 0·076  g/L of potassium is recommended in the irrigation nutrient solution for an inlet load of 75  g m−3 h−1. The influence of the copper concentration was also studied by varying its concentration between the values of 0 and 0·006  g/L. The results have also shown that copper has a minor impact on the biofiltration of methane. This paper is the first report describing the influence of several nutrients in a biofilter. The knowledge provided by this study is necessary for the achievement of a biofilter indebted to methane control.