- Email: [email protected]
The Nitrogen Removal on landfill leachate treatment In reeds Wetland
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576
S39
[E.13] The Nitrogen Removal on landfill leachate treatment In reeds Wetland Bing Xie ∗ , Qian Liu, Chong Hu East China Normal University, China Keywords: Reeds wetland; Total nitrogen; Biomass; Absorption; Removal efficiency; Landfill leachate; Nitrogen remove The remove of the landfill leachate nitrogen is hard to deal with because it contained highly concentration of ammonia. The nitrogen removal capacity of reeds in wetland treating landfill leachate as well as the nitrogen absorption capacity of the reeds was investigated in this paper. The results showed that under the conditions of 0.02m/d of hydraulic loading with landfill leachate COD is 2500 mg/L and ammonia is 2000 mg/L, the reeds on the wetland (with square 200 m2 ) grew rapidly from June to August, the total biomass of reeds reached highest in later August, it is 574 g/m2 . The absorption of nitrogen in different parts of reeds increased quickly during this time, and the aboveground nitrogen absorption had a close positive correlation with its biomass, both the maximum nitrogen absorption of aboveground and underground had occurred in later August. During the whole growth stages of the reed, total nitrogen (TN) content in aboveground parts was higher than underground parts during the same period. The maximum content of the roots of nitrogen appears in November which was 3.9%, while the maximum content of nitrogen in stems and leaves in June which was 6.3%. A timely reeds harvest can remove 3873 g nitrogen in the wetlands, which accounting for 9.28% of total nitrogen removal rate of the landfill leachate. The results suggested that it is feasible to remove the nitrogen from the wetlands by harvesting reeds in right time.
Fig. 1. ICAD.
Internal circulation anaerobic digester—a upflow anaerobic sludge digester
water content was fed, the HRTs of pretreatment and digestion was 1.9 and 10.5d. The average VSS and SS removals and biogas rate reached at 53.9%, 43.3% and 6.0 m3 /m3 sludge (water content of 96%). The average biogas rate decreased because the VSS/SS of feed was only 0.42. The VSS removal and biogas rate were significantly higher than VSS removal of 30% and average biogas rate of 7.5 m3 /m3 sludge (water content of 96%) obtained from full-scale sludge digesters of wastewater treatment plants in China (Wu et al., 2008) in spite of the feed of low organic content. Most full-scale digesters are operated under HRT of 25–30 days and mesophilic conditions. The biogas rate reached 0.60 L/gVSS, which was 46% higher than 0.41 L/gVSS, attained from a CSTR digester combining 70 ◦ C pretreatment of 1 days and thermophilic digestion of 20 days (Gavala et al., 2003). ICAD has satisfactory degradation ability of sludge regardless of water content of 97 or 99%.Acknowledgements: Partially funded by NSFC (50978147), National major science and technology project about water pollution (2008ZX07313-002) and Fok Ying Tung Foundation (114020).
Jing Wu ∗ , Pengjuan Zhao, Lei Tian, Lin Shi, Hanchang Shi
References
doi:10.1016/j.jbiotec.2010.08.110 [E.15]
Tsinghua University, China Keywords: Internal circulation anaerobic digester; Thermophilic anaerobic digestion; Excess activated sludge From both energetic and environmental view, it is a practicable way to produce biogas from the sludge of wastewater treatment plants. A novel sludge digester, internal circulation anaerobic digester (ICAD), is modified on Internal Circulation Anaerobic Reactor treating wastewater (Habets et al., 1997). It employs upflow reactor conception and consists of reaction zone, settling zone, riser and downcomer (Fig. 1). The recirculation driven by recycled biogas significantly improves mass transfer in the digester. ICAD operated under thermophilic conditions (55 ◦ C) with pyrohydrolysis (60 ◦ C) of as pretreatment. The feed was excess activated sludge from an A/A/O system and the water content was 98.9 and 97.1%. The sludge of 98.9% was from secondary settling tank and the 97.1% sludge was from thickening tank. For digestion of sludge of 98.9% water content, HRTs of pretreatment and digestion was 1 and 5.5 d and the average VSS and SS removals and biogas rate reached 60.8%, 45.8% and 12.8 m3 /m3 sludge (water content of 96%). When sludge of 97.1%
Habets, L.H.A., Engelaar, A.J.H.H., Groeneveld, N., 1997. Wat.Sci.Tech. 35 (10). Wu, J., Jiang, J., Zhou, H.M., et al., 2008. China Water and Wastewater. 24 (22). Gavala, H.N., Yenal, U., Skiadas, I.V., Westermann, P., et al., 2003. Water Research. 37.
doi:10.1016/j.jbiotec.2010.08.111
S39
[E.13] The Nitrogen Removal on landfill leachate treatment In reeds Wetland Bing Xie ∗ , Qian Liu, Chong Hu East China Normal University, China Keywords: Reeds wetland; Total nitrogen; Biomass; Absorption; Removal efficiency; Landfill leachate; Nitrogen remove The remove of the landfill leachate nitrogen is hard to deal with because it contained highly concentration of ammonia. The nitrogen removal capacity of reeds in wetland treating landfill leachate as well as the nitrogen absorption capacity of the reeds was investigated in this paper. The results showed that under the conditions of 0.02m/d of hydraulic loading with landfill leachate COD is 2500 mg/L and ammonia is 2000 mg/L, the reeds on the wetland (with square 200 m2 ) grew rapidly from June to August, the total biomass of reeds reached highest in later August, it is 574 g/m2 . The absorption of nitrogen in different parts of reeds increased quickly during this time, and the aboveground nitrogen absorption had a close positive correlation with its biomass, both the maximum nitrogen absorption of aboveground and underground had occurred in later August. During the whole growth stages of the reed, total nitrogen (TN) content in aboveground parts was higher than underground parts during the same period. The maximum content of the roots of nitrogen appears in November which was 3.9%, while the maximum content of nitrogen in stems and leaves in June which was 6.3%. A timely reeds harvest can remove 3873 g nitrogen in the wetlands, which accounting for 9.28% of total nitrogen removal rate of the landfill leachate. The results suggested that it is feasible to remove the nitrogen from the wetlands by harvesting reeds in right time.
Fig. 1. ICAD.
Internal circulation anaerobic digester—a upflow anaerobic sludge digester
water content was fed, the HRTs of pretreatment and digestion was 1.9 and 10.5d. The average VSS and SS removals and biogas rate reached at 53.9%, 43.3% and 6.0 m3 /m3 sludge (water content of 96%). The average biogas rate decreased because the VSS/SS of feed was only 0.42. The VSS removal and biogas rate were significantly higher than VSS removal of 30% and average biogas rate of 7.5 m3 /m3 sludge (water content of 96%) obtained from full-scale sludge digesters of wastewater treatment plants in China (Wu et al., 2008) in spite of the feed of low organic content. Most full-scale digesters are operated under HRT of 25–30 days and mesophilic conditions. The biogas rate reached 0.60 L/gVSS, which was 46% higher than 0.41 L/gVSS, attained from a CSTR digester combining 70 ◦ C pretreatment of 1 days and thermophilic digestion of 20 days (Gavala et al., 2003). ICAD has satisfactory degradation ability of sludge regardless of water content of 97 or 99%.Acknowledgements: Partially funded by NSFC (50978147), National major science and technology project about water pollution (2008ZX07313-002) and Fok Ying Tung Foundation (114020).
Jing Wu ∗ , Pengjuan Zhao, Lei Tian, Lin Shi, Hanchang Shi
References
doi:10.1016/j.jbiotec.2010.08.110 [E.15]
Tsinghua University, China Keywords: Internal circulation anaerobic digester; Thermophilic anaerobic digestion; Excess activated sludge From both energetic and environmental view, it is a practicable way to produce biogas from the sludge of wastewater treatment plants. A novel sludge digester, internal circulation anaerobic digester (ICAD), is modified on Internal Circulation Anaerobic Reactor treating wastewater (Habets et al., 1997). It employs upflow reactor conception and consists of reaction zone, settling zone, riser and downcomer (Fig. 1). The recirculation driven by recycled biogas significantly improves mass transfer in the digester. ICAD operated under thermophilic conditions (55 ◦ C) with pyrohydrolysis (60 ◦ C) of as pretreatment. The feed was excess activated sludge from an A/A/O system and the water content was 98.9 and 97.1%. The sludge of 98.9% was from secondary settling tank and the 97.1% sludge was from thickening tank. For digestion of sludge of 98.9% water content, HRTs of pretreatment and digestion was 1 and 5.5 d and the average VSS and SS removals and biogas rate reached 60.8%, 45.8% and 12.8 m3 /m3 sludge (water content of 96%). When sludge of 97.1%
Habets, L.H.A., Engelaar, A.J.H.H., Groeneveld, N., 1997. Wat.Sci.Tech. 35 (10). Wu, J., Jiang, J., Zhou, H.M., et al., 2008. China Water and Wastewater. 24 (22). Gavala, H.N., Yenal, U., Skiadas, I.V., Westermann, P., et al., 2003. Water Research. 37.
doi:10.1016/j.jbiotec.2010.08.111