Integrating recycle stream ammonia treatment with biological nutrient removal

An apparatus for removing ammonia from a waste stream, comprising:

• one or more separating devices for separating an anaerobically digested waste stream into a solids-rich stream and a solids-depleted stream;
• an ammonia recovery system for recovering ammonia from the solids-depleted stream, comprising:
• a base source for adding one or more bases to the solids-depleted stream, and
• one or more vapor removal devices for transforming ammonia in the solids-depleted stream into the vapor phase and subsequently collecting the ammonia in a liquid stream, thereby forming the ammonia liquid stream and a return stream;
• and
• a biological ammonia removal system to remove ammonia from the solids-depleted stream, the biological ammonia removal system comprising a nitrification system, wherein the return stream is flowable through a return pathway from the ammonia recovery system to the biological ammonia removal system.

A method of removing ammonia from a stream, comprising:

• separating a nitrogen containing stream into a first solids-depleted stream and a first solids-rich stream;
• treating the first solids-rich stream with a hydrothermal process to produce an ammonium containing treated solids-rich stream;
• separating the treated solids-rich stream into a second solids-rich stream and an ammonium containing second solids-depleted stream;
• using an ammonia recovery process for removing the ammonia from the second solids-depleted stream, comprising:
• adding a sufficient amount of one or more bases to the second solids-depleted stream to convert the ammonium to ammonia and the bicarbonate to carbonate, and
• transforming the ammonia into the vapor phase and subsequently collecting the ammonia in a liquid stream using one or more vapor removal devices, thereby separating the liquid ammonia stream from a return stream;
• conducting a biological process to remove ammonia from the first solids-depleted stream, the biological process comprising a nitrification process;
• and
• flowing the return stream into the biological process.