摘要 |
A new system is disclosed for extracting ammonia from a wastewater stream, and for transferring the ammonia into the secondary water circuit, where the dissolved ammonium is electrolysed and transformed into gaseous nitrogen. The new system makes use of a membrane of gas--permeable hydrophobic material. The wastewater is raised to pH of 11, and 50.degree.C, to make the transfer of ammonia through the membrane more efficient. Also disclosed is a process-control system for the ammonium disposal system, in which pH sensors are used to control operation. Instruments for measuring ammonia-concentration directly are expensive, whereas pH- sensors are simple, reliable, and responsive. Disclosed are procedures for establishing the relationships between pH and the progress of the ammonium disposal treatment.
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