A method for energy-efficient and simultaneous nitrogen removal from wastewater and desalination of saline water
Description:
A method for energy-efficient and simultaneous nitrogen removal from wastewater and desalination of saline water
Partial nitration combined with anaerobic ammonium oxidation (anammox process)
Background
Annamox is a fully autotrophic anaerobic ammonium oxidation process with nitrate as an electron acceptor and fixed carbon from CO2 as a carbon source. Partial nitritation is a process in which partial amounts of ammonium are oxidized to produce nitrite. The PN anammox process is a combination of PN and anammox process in which almost half of the ammonium nitrogen in the wastewater is transformed into nitrite and the remaining ammonium and produced nitrite are converted into nitrogen gas under the metabolic action of anammox bacteria.
Technology Overview
This technology of partial nitration combined with anaerobic ammonium oxidation (anammox process) reduces the oxygen and chemical demands of the conventional nitrogen removal process of nitrification-denitrification.
In this innovation, a four-chambered microbial desalination cell was developed with one anode, one desalination chamber, and two cathodes (two-stage PN-anammox chamber).The effect of dissolved oxygen (DO), anode COD, salt concentration in the desalination chamber, on ammonium removal were systematically investigated. Power generation, salinity removal, nitrogen removal efficiency, energy balance, and electrochemical performances of the system were investigated.
The two-stage nitration-anammox process is defined as the most promising energy and cost saving alternative to the conventional biological removal process. The performance of a two-stage partial-nitration-anammox biocathode integrated microbial desalination cell for nitrogen removal, desalination and bioelectricity generation was analyzed. This system achieved the maximum total nitrogen removal rate of maximum powder production. The organic removal in the anode chamber produced a good rate to fit the first order reaction model. The maximum energy still enabled net energy to remain within a positive flow rate. Therefore, this integration of the partial nitration anammox process with MDC provides energy and resource efficient synergy for bio‑electrochemical wastewater treatment.
Benefits
‑ Cost effective
‑ Resource efficient
Applications
There are many biological, chemical and physical technologies for the removal of nitrogen in wastewater which is a critical pollutant of concern. The invented process is chemical and energy efficient and cost effective compared to other existing technologies.
Opportunity
Wastewater utilities and industrial sectors required to treat wastewater with high organic and nitrogen contaminants would be interested in this invention. Agricultural, dairy and animal feeding facilities will also benefit from this cost-effective process