Inhibitory effect of high calcium concentration on municipal solid waste leachate treatment by the activated sludge process

2017 ◽  
Vol 35 (5) ◽  
pp. 508-514 ◽  
Author(s):  
Yi Xia ◽  
Pin Jing He ◽  
Hong Xia Pu ◽  
Fan Lü ◽  
Li Ming Shao ◽  
...  

This research focused on the inhibitory effects of Ca on the aerobic biological treatment of landfill leachate containing extremely high Ca concentrations. When the Ca concentration in leachate to be treated was more than 4500 mg l−1, the total organic carbon removal rate was significantly reduced and the processing time to achieve the same removal efficiency was 1.4 times that in the control treatment without added Ca. In contrast, the total nitrogen and ammonia nitrogen (NH4+–N) removal efficiencies were positively related to the Ca concentration, increasing from 65.2% to 81.2% and from 69.2% to 83.7%, respectively, when the dosage of added Ca increased from zero to 8000 mg l−1. During aerobic treatment, the reductions of solution Ca concentration were in the range of 1003–2274 mg l−1 and were matched with increases in the Ca content in the residual sludge. The inhibition threshold of Ca in the leachate treated by the activated sludge process appeared to be 4500 mg l−1, which could be realized by controlling the influent Ca concentration and using an appropriate sludge return ratio in the activated sludge process.

2012 ◽  
Vol 610-613 ◽  
pp. 2006-2011
Author(s):  
Chun Yan Xu ◽  
Hong Jun Han

Full scale two-stage activated sludge process (ASP) with fixed biological media was used to treat coal gasification wastewater. The ASP has operated for more than one year and COD, total phenol and NH4-N removal effects were illuminated. COD and total phenol removal rates were around 85% and 90% during long term operation. Effluent COD and total phenol of the first stage of the ASP had an abnormal increase and turned to normal after several weeks. Nitrification of the ASP increased slowly and NH4-N removal rates achieved 80% after 15 weeks. Stenotrophomonas maltophilia K279a is isolated from coal chemical industry wastewater. The optimum conditions for PO production are phenol 1000mg/L, temperature 30-34 and pH 7-7.5. The strain resists 980mg/L COD and 805mg/L phenols. The degradation rate of phenols reaches 97% in 48h. The results show that Stenotrophomonas maltophilia K279a can be applied to the aerobic process with high proportion of phenols


2013 ◽  
Vol 807-809 ◽  
pp. 694-698
Author(s):  
Rong Xin Huang ◽  
Zhen Xing Wang ◽  
Gang Liu ◽  
Qi Jin Luo

In order to guarantee the reliability and security of reclaiming water, research on the removal efficiency of the environmental endocrine chemicals (EDCs) --the Phthalate Esters (PAEs) in conventional secondary activated sludge and wastewater reclamation and reuse process was undergoing at Harbin wastewater treatment plant (WWTP). The wastewater samples were colleted from every unit effluent of WWTP. The results showed that contamination of EDCs were presented in municipal wastewater at Harbin and the concentrations of the four PAEs were 21.01μg/L for Di-n-butyl Phthalate (DBP); 9.63μg/L for Di-n-octyl Phthalate (DnOP); 4.56μg/L for Diethyl Phthalate (DEP); 1.96μg/L for Dimethyl Phthalate (DMP) respectively in the influent. The conventional activated sludge has good removal efficiencies performance on DMP, DEP and DBP. With the increasing of molecular weight and branch chains of PAEs contaminations, the removal rate of the four PAEs in the conventional activated sludge process decreased from 99.82%(DMP),90.60%(DEP),90.10%(DBP) to the only 45.13% removal rate for DnOP, which was mostly removed from primary treatment but no from secondary activated sludge process; Coagulation-air flotation plus filtration process was not a feasible way to remove PAEs from reclaiming treatment units.


2017 ◽  
Vol 76 (2) ◽  
pp. 386-395 ◽  
Author(s):  
Te Wang ◽  
Jian Li ◽  
Ling Hua Zhang ◽  
Ying Yu ◽  
Yi Min Zhu

To improve the efficiency of simultaneous heterotrophic nitrification and aerobic denitrification (SND) at high concentrations of NaCl and ammonia nitrogen (NH4+—N), we investigated the SND characteristics of Halomonas bacteria with the ability to synthesize the compatible solute ectoine. Halomonas sp. strain B01, which was isolated, screened and identified in this study, could simultaneously remove nitrogen (N) by SND and synthesize ectoine under high NaCl conditions. Gene cloning and sequencing analysis indicated that this bacterial genome contains ammonia monooxygenase (amoA) and nitrate reductase (narH) genes. Optimal conditions for N removal in a solution containing 600 mg/L NH4+–N were as follows: sodium succinate supplied as organic carbon (C) source at a C/N ratio of 5, pH 8 and shaking culture at 90 rpm. The N removal rate was 96.0% under these conditions. The SND by Halomonas sp. strain B01 was performed in N removal medium containing 60 g/L NaCl and 4,000 mg/L NH4+–N; after 180 h the residual total inorganic N concentration was 21.7 mg/L and the N removal rate was 99.2%. Halomonas sp. strain B01, with the ability to synthesize the compatible solute ectoine, could simultaneously tolerate high concentrations of NaCl and NH4+–N and efficiently perform N removal by SND.


1999 ◽  
Vol 7 (1) ◽  
pp. 63-70 ◽  
Author(s):  
L.J.S. Lukasse ◽  
K.J. Keesman ◽  
G. van Straten

2012 ◽  
Vol 518-523 ◽  
pp. 2391-2398
Author(s):  
Yan He ◽  
Gong Ming Zhou ◽  
Min Sheng Huang ◽  
Min Tong

Three kinds of seeding sludge, i.e. conventional activated sludge, anaerobic granular sludge and the nitrifying activated sludge from the nitritation reactor treating aged leachates were evaluated in batch mode to screen the optimized inoculum for the rapid start-up of ANAMMOX reactor. The feasibility of the ANAMMOX process for the treatment of aged leachates was also investigated in a modified upflow anaerobic sludge blanket (UASB, 0.05m3). The batch experiments revealed that the nitrifying activated sludge from the nitritation reactor could respectively achieve the NRR (nitrogen removal rate) of 0.0365 kg N/(m3.d) and the ARR (ammonium removal rate) of 0.013 kg N/(m3.d) on day 12, which were greatly higher than those of the other two tested sludge samples. The mixture of the aforementioned nitrifying activated sludge and anaerobic granular sludge was established as an effective inoculum for the prompt start-up of ANAMMOX reactor. The maximum total nitrogen removal rate of 0.826 kg N/(m3.d) could be obtained for the treatment of “old” leachates under NLR (nitrogen loading rate) of 1.028 kg N/(m3.d). It is concluded that the N-removal performance of ANAMMOX process is still to be improved for actual engineering application to aged landfill leachates.


1991 ◽  
Vol 18 (6) ◽  
pp. 940-944 ◽  
Author(s):  
J. B. Sérodes ◽  
E. Walsh ◽  
O. Goulet ◽  
J. de la Noue ◽  
C. Lescelleur

Design criteria of a pilot plant for treating secondary municipal effluents using filamentous, bioflocculating micro-algae were evaluated. Using a sequential batch reactor, the best removal rate of ammonia nitrogen was reached for 25% draw volume; at 20–22 °C, up to four cycles per day could be achieved giving a removal efficiency of approximately 2 g of N per day and per square meter of basin (200 mm deep) with negligible nitrogen residual; increasing the water level by increments of 200 mm (from 200 to 600 mm) increased the N removal efficiency in a way similar to an increase in the number of renewals per day on a 200 mm deep basin. The dominant micro-algae (Chlorhormidium) was heavily influenced by the water temperature. Key words: micro-algae, municipal wastewater, water treatment, ammonia nitrogen, removal rate, removal efficiency.


2012 ◽  
Vol 518-523 ◽  
pp. 569-574
Author(s):  
Qiong Wan ◽  
Lei Li ◽  
Dang Cong Peng

Enhancing nitrification from municipal wastewater by bioaugmentation was investigated in a pilot plant operated in A2/O process. Reject water was used to cultivate nitrifier in O/A process (side stream), and the exceed sludge in side stream was used to bioaugmentation. The experimental results showed that bioaugmentation was very effective for enhancing nitrification. After nitrifier bioaugmentation, the NH4+-N removal rate was improved more than 30% in main stream. And AUR and NUR of the activated sludge increased from 2.61 mgNH4+-N /(gMLSS•h) and 2.38 mgNO2--N/(gMLSS•h) to 5.32 mgNH4+-N /(gMLSS•h) and 3.81 mgNO2--N/(gMLSS•h), which was as 2.04 times and 1.60 times as those of before bioaugmentation in main stream respectively.


2014 ◽  
Vol 69 (10) ◽  
pp. 2052-2058 ◽  
Author(s):  
Wenliang Chen ◽  
Chonghua Yao ◽  
Xiwu Lu

Optimal design of activated sludge process (ASP) using multi-objective optimization was studied, and a benchmark process in Benchmark Simulation Model 1 (BSM1) was taken as a target process. The objectives of the study were to achieve four indexes of percentage of effluent violation (PEV), overall cost index (OCI), total volume and total suspended solids, making up four cases for comparative analysis. Models were solved by the non-dominated sorting genetic algorithm in MATLAB. Results show that: ineffective solutions can be rejected by adding constraints, and newly added objectives can affect the relationship between the existing objectives; taking Pareto solutions as process parameters, the performance indexes of PEV and OCI can be improved more than with the default process parameters of BSM1, especially for N removal and resistance against dynamic NH4+-N in influent. The results indicate that multi-objective optimization is a useful method for optimal design ASP.


2011 ◽  
Vol 396-398 ◽  
pp. 1944-1949
Author(s):  
Cai Yan He ◽  
Yan Xu ◽  
Yan Yan Chen ◽  
Sheng Yu ◽  
Jing Ming Liu

Aiming at the problem of lower removal efficiency of ammonia nitrogen in the activated sludge process for wastewater treatment plant of Jilin Chemical Company, a few tests were studied such as filler selection, biological hydrolysis-acidification process, nitrobacteria cultivation, activated sludge process and biofilm process, the feasibility of simultaneous nitrification and denitrification(SND) was developed with biofilm treatment for chemical poor-biological wastewater. The results showed that: SND occurred in the aerobic section, effluent total basicity (TB) in biofilm process was 2mmol / L or more, and was higher than activated sludge process, while the effluent TB in activated sludge process was about 0.1mmol / L,and nitrate produced by activated sludge process was 30mg/L higher than that of biofilm process. Nitrogen removal efficiency using SJ-1-type filler made in Jiangsu Suzhou Purification Group Co., Ltd was 15.01% more than that using combined filler.


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