The use of zeolites for biogas purification in agricultural production Varvara Druzyanova, Sofya Petrova, Nadezhda Khiterkheeva, Irina Bardamova and Tatyana Gergenova E3S Web Conf., 175 (2020) 12012 Published online: 29 June 2020 DOI: 10.1051/e3sconf/202017512012