Improving the Efficiency of Organic Fertilizer and Nitrogen Use via Air Plasma and Distributed Renewable Energy

Abstract

Synthesis of reactive forms of nitrogen such as ammonia is important in modern agricultural productivity, but present agricultural technology uses reactive nitrogen inefficiently, leading to numerous and growing environmental problems. Animal, human, and food waste all contain significant quantities of organic nitrogen that are transformed into ammonia (NH3) by bacterial degradation of organic waste. If not captured, this volatile form of reactive nitrogen is lost to the environment, reducing N content and thus the agricultural value of organic waste. Furthermore, ammonia loss to the environment initiates a cascade of environmental problems. Nonequilibrium air plasma technology creates reactive nitrogen that can be readily converted to dilute aqueous nitric acid solutions. If mixed with decaying organic waste, NH3 loss is greatly reduced via the formation of involatile ammonium nitrate, a potent nitrogen fertilizer. Air plasma technology for fixed nitrogen manufacture is currently limited only by the availability of electricity and the energy efficiency of the process. The price of electricity via distributed renewable routes such as solar photovoltaic or wind turbines is rapidly decreasing. Increasingly, inexpensive wind and solar power sources, coupled with recent advances in air plasma energy efficiency, suggest that this technology could have a significant role in improving nitrogen use efficiency and reducing environmental and other threats associated with the current system.