Ammonia in the recirculation of biogas for mixing.

The biogas plant which we are planning, the feeding material is rich in nitrogen content. we are going for biogas recirculation for mixing. Ammonia production will be high. Recirculation of biogas with high ammonia, I guess it will increase the toxic level which affects the micro-organism more. Give me some suggestion to overcome with the issue of ammonia and what's the best technology for ammonia striping. Some suggestion will be helpful for me.

Thanks.