Nitrogen resource recovery from mature leachate via heat extraction technology: An engineering project application

Abstract

Large pool of ammonia in mature leachate is challenging to treat with a membrane bioreactor system to meet the discharge standard for pollution control of municipal solid waste landfills in China (GB 16889-2008) without external carbon source addition. In this study, an engineering leachate treatment project with a scale of 2,000 m3/d was operated to evaluate the ammonia heat extraction system (AHES), which contains preheat, decomposition, steam-stripping, ammonia recovery, and centrifuge dewatering. The operation results showed that NH3-N concentrations of raw leachate and treated effluent from an ammonia heat extraction system (AHES) were 1,305–2,485 mg/L and 207–541 mg/L, respectively. The ratio of COD/NH3-N increased from 1.40–1.84 to 7.69–28.00. Nitrogen was recovered in the form of NH4HCO3 by the ammonia recovery tower with the introduction of CO2, wherein, the mature leachate can offer 37% CO2 consumption. The unit consumptions of steam and power were 8.0% and 2.66 kWh/m3 respectively, and the total operation cost of AHES was 2.06 USD per cubic leachate. These results confirm that the heat extraction is an efficient and cost-effective technology for the recovery of nitrogen resource from mature leachate.

A Novel 4-Set Venn Diagram Model Based on High-Resolution Mass Spectrometry To Monitor Wastewater Treatment

“…Based on the above III 1 −III 6 modes, the bypass of the influent around U 1 or U 2 is included to reflect the scenario of step feed in the active sludge process, ammonia stripping as pretreatment, 34 supplement of a carbon source for denitrification, 33 and anaerobic ammonium oxidation. 35 some modes might not be commonly applied in real wastewater treatment projects.…”

“…Based on the above III 1 –III 6 modes, the bypass of the influent around U 1 or U 2 is included to reflect the scenario of step feed in the active sludge process, ammonia stripping as pretreatment, supplement of a carbon source for denitrification, and anaerobic ammonium oxidation . Therefore, 18 modes with bypass (i.e., III 11 –III 13 , III 21 –III 23 , III 31 –III 33 , III 41 –III 43 , III 51 –III 53 , and III 61 –III 63 ) are involved for III 1 –III 6 modes to guarantee the integrality of the model, though some modes might not be commonly applied in real wastewater treatment projects.…”