EVALUATION OF THE TREATABILITY OF MUNICIPAL WASTE LANDFILL LEACHATE IN A SBR AND BY COAGULATION-FLOCCULATION ON A BENCH SCALE

Fleck, E.; Gewehr, A. G.; Cybis, L. F. A.; Gehling, G. R.; Juliano, V. B.

doi:10.1590/0104-6632.20160334s20150126

Acessibilidade / Reportar erro

Brasil

Brazilian Journal of Chemical Engineering

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Environmental Engineering • Braz. J. Chem. Eng. 33 (4) • Oct-Dec 2016 • https://doi.org/10.1590/0104-6632.20160334s20150126 copy

EVALUATION OF THE TREATABILITY OF MUNICIPAL WASTE LANDFILL LEACHATE IN A SBR AND BY COAGULATION-FLOCCULATION ON A BENCH SCALE

Authorship SCIMAGO INSTITUTIONS RANKINGS

Abstract

This article describes bench scale sequential, biological and coagulation-flocculation treatment of mature leachate for the removal of nitrogen and biodegradable and recalcitrant carbonaceous material. The biological stage was conducted on two SBRs, one of which inoculated with nitrifying sludge, another without an inoculum, for 152 and 133 days, respectively. The coagulation-flocculation stage used four coagulants at different doses and pH adjustments. The treatment conducted on the inoculated SBR when a pH control was used produced mean removals of BOD₅, COD and TKN of 69.6%, 38.5% and 51.6%, respectively, and practically complete denitrification. Coagulation-flocculation applied to the effluent of the inoculated biological reactor showed a superior effectiveness of the ferric coagulants, when the pH was adjusted to close to 6.0, producing removals of turbidity, COD and true color close to 95%, 78% and 92%, respectively.

Keywords:
Leachate; Sequential batch reactor; Nitrification; Coagulation; Flocculation

Author	Conditions	Results
*Tengrui et al. (2007)*Tengrui, L., Al-Harbawi, A. F., Bo, L. M., Jun, Z., Long, X. Y., Characteristics of nitrogen removal from old landfill leachate by sequencing batch biofilm reactor. American Journal of Applied Sciences, 4(4), 211-214 (2007).	Old leachate with 1100 mgNH₄-N.L^-1, applied at 0.51 kgN.m^-3.d^-1 in an aerated biofilter maintained at 30-33 ºC, with pH maintained at 7.4-8.6, HRT: 9h.	TKN removal of 99%
Spagni and Libelli (2009)Spagni, A., Marsili-Libelli, S., Nitrogen removal via nitrite in a sequencing batch reactor treating sanitary landfill leachate. Bioresource Technology, 100, 609-614 (2009).	Old leachate, with 1319-1530 mgTKN.L^-1 and 2623-2055 mgCOD.L^-1 applied in a laboratory-scale SBR	Nitrification and nitrogen removal were usually higher than 98% and 95%, respectively, whereas COD removal was approximately 20-30%; 0.117-0.3 mgN.mgMLVSS^-1.d^-1
*He et al. (2007)*He, Y., Zhou, G., Zhao, Y., Nitrification with high nitrite accumulation for the treatmentof "old" landfill leachates. Environmental Engineering Science, 24(8), 1084-1094 (2007).	Leachate with 2900 mgNH₄-N.L^-1 and 220 mgCOD. L^-1 applied in a 150 L SBR	0.0690-0.2843 gTKN.gMLVSS^-1.d^-1
Liang and Liu (2006)Liang, Z., Liu, J.-X., Control factors of partial nitritation for landfill leachate treatment. Journal of Environmental Sciences, 19, 523-529 (2007).	Leachate with 1800-1300 mgTKN.L^-1 and 1500-16,000 mgCOD.L^-1 applied at a rate of 0.2-1.0 kgN.m^-3.d^-1 in a aerobic biological reactor	TKN removal of 60%-74%

Author	Leachate tested	Coagulant / Dosage	pH adjustment	COD removal
*Wang et al. (2002)*Wang, Z.-P., Zhang, Z., Lin, Y.-J., Deng, N.-S., Tao, T., Zhuo, K., Landfill leachate treatment by a coagulation-photooxidation process. Journal of Hazardous Materials, B95, p. 153-159 (2002).	raw	FeCl₃; 0.34 gFe⁺³.L^-1	7.6	24%
Lin and Chang (2000)Lin, C. Y., Chang, F. Y., Chang, C. H., Co-digestion of leachate with septage using a UASB reactor. Bioresource Technology, 73, 175-178 (2000).	old	0.2 gPACL^-1	5.0	70%
*Guo et al. (2010)*Guo, J.-S., Abbas, A. A., Chen, Y. P., Liu, Z. P., Fang, F., Chen, P., Treatment of landfill leachate using a combined stripping, fenton, SBR, and coagulation process. Journal of Hazardous Materials, 178, 699-705 (2010).	pre-treated	FeCl₃; 0.28 gFe⁺³.L^-1	5.0	36%
*Castrillón et al. (2010)*Castrillón, L., Nava, Y. F., Ulmanu, M., Anger, I., Marañón, E., Physico chemical and biological treatment of MSW landfill leachate. Waste Management, 30, 228-235 (2010).	raw	4.0 gPAC.L^-1	6.5	34%
*Castrillón et al. (2010)*Castrillón, L., Nava, Y. F., Ulmanu, M., Anger, I., Marañón, E., Physico chemical and biological treatment of MSW landfill leachate. Waste Management, 30, 228-235 (2010).	raw	FeCl₃; 0.59 gFe⁺³.L^-1	5.0	73%
*Rui et al. (2012)*Rui, L. M., Daud, Z., Latif, A. A. A., Coagulation-flocculation in leachate treatment by using ferric chloride and alum as coagulant. International Journal of Engineering Research and Applications, 2(4), 1929-1934 (2012).	old	FeCl₃; 1.03 gFe⁺³.L^-1	7.0	37%
*Samadi et al. (2010)*Samadi, M. T., Saghi, M. H., Rahmani, A., Hasanvand, J., Rahimi, S., Shirzad Syboney, M., Hamadan landfill leachate treatment by coagulation-flocculation process. Iran. J. Environ. Health Sci. Eng., 7(3), 253-258 (2010).	raw	Fe₂(SO₄)₃; 0.42 gFe⁺³.L^-1	12.0	71%
*Pi et al. (2009)*Pi, K. W., Li, Z., Wan, D. J., Gao, L. X., Pretreatment of municipal landfill leachate by a combined process. Process Safety and Environmental Protection, 87, 191-196 (2009).	air stripping effluent	FeCl₃; 0.21 gFe⁺³.L^-1	9.0	37%
*Tatsi et al. (2003)*Tatsi, A. A., Zouboulis, A. I., Matis, K. A., Samaras, P., Coagulation-flocculation pretreatment of sanitary landfill leachates. Chemosphere, 53, p. 737-744. (2003)	partially stabilized by recirculation	FeCl₃; 0.69 gFe⁺³.L^-1	10.0	80%

Parameters	Unit	Maximum	Minimum	Mean	^s s: standard deviation; ND: not detected
pH	-	8.47	8.00	8.30	0.12
Conductivity	mS.cm^-1	28.7	19.4	26.2	4.5
Chemical Oxygen Demand	mgO₂.L^-1	7272	3039	4786	857
Biochemical Oxygen Demand, 5d, 20 ºC	mgO₂.L^-1	2200	1250	1617	312
BOD₅/COD	-	0.48	0.24	0.30	0.08
Unfiltered turbidity	FAU	1400	925	1093	159
Filtered turbidity	FAU	1053	625	782	119
True color	mgPt-Co.L^-1	18,564	1200	10,353	2589
Ammoniacal nitrogen	mgN.L^-1	1792	1030	1441	207
Total Kjeldahl nitrogen	mgN.L^-1	1961	1344	1607	164
Nitrate	mgN.L^-1	9.54	ND	3.90	2.31
Nitrite	mgN.L^-1	3.10	ND	0.60	0.81
Alkalinity	mgCaCO₃.L^-1	14,400	5630	7970	2220
Total solids	mg.L^-1	17,670	14,935	15,911	1516
Total volatile solids	mg.L^-1	4092	3207	3740	469
Total fixed solids	mg.L^-1	13,578	11,015	12,171	1300
Total suspended solids	mg.L^-1	2060	1080	1653	511
Volatile suspended solids	mg.L^-1	1020	460	773	286
Fixed suspended solids	mg.L^-1	1040	620	880	227

Variable / Coagulant	PAC	Ferric Chloride	Ferric Sulphate	Tannin
Effluent Initial Characteristics	Turbidity: 675-683 FAU;	Turbidity: 725-1044 FAU;	Turbidity: 667-800 FAU;	Turbidity: 675-750 FAU;
	COD: 2672-2987 mgO₂.L^-1;	COD: 2761-3168 mgO₂.L^-1;	COD: 2870-3244 mgO₂.L^-1;	COD: 2844-3168 mgO₂.L^-1;
	Color: 9400-11,575 mgPt-Co.L^-1	Color: 11,100-12,100 mgPt-Co. L^-1	Color: 9400-11,575 mgPt-Co.L^-1	Color: 9400-11,475 mgPt-Co. L^-1
Fast mixing time (min)^* * preliminary tests	0.5, 1, 2, 3 , 4, 6
Fast mixing gradient (s^-1)^* * preliminary tests	180, 350, 425, 600, 950, 1200
Slow mixing time (min)^* * preliminary tests	5, 10, 15, 20, 30, 45
Slow mixing gradient (s^-1)^* * preliminary tests	10, 20, 40, 60, 80, 100
Initial pH (first tests)^ definitive tests using quick mixing for 2 minutes at 250 s-1, slow mixing for 20 minutes at 60 s-1 and 2-hour sedimentation time	5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.1, 8.5, 9.0, 9.5, 10.0	5.0, 5.5, 6.0, 6.6, 7.0, 7.5, 8.0, 8.5, 8.9, 9.0, 9.5, 10.0	5.0, 5.5, 6.0, 6.6, 7.0, 7.5, 8.0, 8.5, 8.6, 9.0, 9.5, 10.0	5.0, 5.5, 6.0, 7.0, 7.2, 7.5, 8.0, 8.5, 8.9, 9.0, 9.5, 10.0
Dosages (first tests)^ definitive tests using quick mixing for 2 minutes at 250 s-1, slow mixing for 20 minutes at 60 s-1 and 2-hour sedimentation time	0.50, 1.00, 1.50, 2.00, 3.00, 4.00 g Al₂O₃.L^-1	0.17, 0.34, 0.69, 1.03, 1.38, 1.72 g Fe⁺³.L^-1	0.20, 0.50, 0.80, 1.00, 1.50, 2.00 g Fe⁺³.L^-1	1.00, 2.00, 3.00, 4.00, 6.00, 8.00 g.L^-1
Initial pH (final tests)^ definitive tests using quick mixing for 2 minutes at 250 s-1, slow mixing for 20 minutes at 60 s-1 and 2-hour sedimentation time	6.4, 6.7, 7.0, 7.3, 7.5, 7.8	5.7, 5.9, 6.1, 6.3, 6.5, 6.7	5.4, 5.6, 5.8, 6.0, 6.2, 6.4	5.3, 5.5, 5.7, 5.9, 6.1, 6.3
Dosages (final tests)^ definitive tests using quick mixing for 2 minutes at 250 s-1, slow mixing for 20 minutes at 60 s-1 and 2-hour sedimentation time	0.90, 1.10, 1.30, 1.50, 1.70, 1.90 g Al₂O₃.L^-1	0.55, 0.62, 0.69, 0.76, 0.83, 0.90 g Fe⁺³.L^-1	0.80, 0.90, 1.00, 1.10, 1.20, 1.30 g Fe⁺³.L^-1	6.00, 7.00, 8.00, 9.00, 10.00, 12.00 g.L^-1

ANOVA Tests Within Reactors	SBR1 pH control x no pH control	SBR2 pH control x no pH control
MLVSS	DSS 2.5%	DNSS 5%
TKN removal	DNSS 5%	DSS 0.5%
mgN.mgMLVSS^-1.d^-1	DNSS 5%	DSS 0.05%
ANOVA Tests SBR1 xSBR2	Cycles with no pH control	Cycles with pH control
MLVSS	DSS 0.05%	DSS 1%
TKN removal	DSS 0.05%	DSS 0.05%
mgN.mgMLVSS^-1.d^-1	DSS 2.5%	DSS 0.05%

Coagulant	PAC	Ferric Chloride	Ferric Sulphate	Tannin
Dosages used	0.50, 1.00, 1.50, 2.00, 3.00, 4.00 g Al₂O₃.L^-1	0.17, 0.34, 0.69, 1.03, 1.38, 1.72 g Fe⁺³.L^-1	0.20, 0.50, 0.80, 1.00, 1.50, 2.00 g Fe⁺³.L^-1	1.00, 2.00, 3.00, 4.00, 6.00, 8.00 g.L^-1
Optimal dosage found	1.50gAl₂O₃. L^-1	0.69gFe⁺³.L^-1	1.00gFe⁺³.L^-1	8.00g.L^-1
Color removal (%)	92.33	90.54	96.99	81.83
Turbidity removal (%)	96.15	94.62	97.78	90.07
COD removal (%)	74.66	82.20	84.95	16.95
Final pH	3.8	3.41	4.45	6.17
Final Color (mgPt-Co.L^-1)	721	1050	283	2017
Final turbidity (FAU)	26	39	15	72
Final COD (mgO₂.L^-1)	678	564	432	2631

Coagulant	PAC	Ferric Chloride	Ferric sulphate	Tannin
Dosages used	1.50g Al₂O₃. L^-1	0.69gFe⁺³.L^-1	1.00gFe⁺³.L^-1	8.00g.L^-1
Optimal pH found	7.0	6.5	6.0	6.0
Color removal (%)	88.97	95.25	97.36	88.30
Turbidity removal (%)	94.88	97.89	93.25	93.19
COD removal (%)	52.75	78.56	84.90	19.62
Final pH	4.49	5.19	3.51	6.25
Final color (mgPt-Co.L^-1)	1053	575	267	1100
Final turbidity (FAU)	35	22	45	46
Final COD (mgO₂.L^-1)	1359	592	461	2286

Brazilian Society of Chemical Engineering Rua Líbero Badaró, 152 , 11. and., 01008-903 São Paulo SP Brazil, Tel.: +55 11 3107-8747, Fax.: +55 11 3104-4649, Fax: +55 11 3104-4649 - São Paulo - SP - Brazil
E-mail: rgiudici@usp.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] *To whom correspondence should be addressed

APHA	American Public Health Association
AWWA	American Water Works Association
BOD₅	Biochemical Oxygen Demand in 5 days
COD	Chemical Oxygen Demand
FAU	Formazin Attenuation Unit
g:	gradient
HRT	Hydraulic Retention Time
MLVSS	Mixed Liquor Volatile Suspended Solids
MLVSS.L^-1	mixed liquor volatile suspended solids milligram per liter
PAC	polyaluminum chloride
SBR	Sequencial Batch Reactor
TSS	Total Suspended Solids
TKN	Total Kjeldahl Nitrogen
WEF	Water Environment Federation