Treatment of landfill leachates by comparing advanced oxidation and coagulation-flocculation processes coupled with activated carbon adsorption

2000 ◽  
Vol 41 (1) ◽  
pp. 231-235 ◽  
Author(s):  
R.M. Ramíirez Zamora ◽  
A. Durán Moreno ◽  
M.T. Ortade Velásquez ◽  
I. Monje Ramírez

This work compares two pre-treatments (coagulation-flocculation process (CF) and the Fenton oxidation Method (FE)) of the activated carbon adsorption process (AC) to optimize the removal of the organic compounds in landfill leachates. The content of organic compounds was measured in terms of three global parameters: colour, chemical oxygen demand (COD) and dissolved organic carbon (DOC). The result obtained in discontinuous reactor conditions showed an increase in colour removal from 1.5 to 2.0 times and a decrease of COD between 0.3 to 0.5 times for the FE-AC treatment, in relation to the CF-AC treatment. On the other hand, the data obtained in continuous reactor conditions (packed columns) showed that the column fed with leachate CF exhibited operation times 1.3 times longer and a better physiochemical quality in the filtrate (COD and colour) than the one fed with the FE leachate. Nevertheless, the adsorption capacities in the colour removal column of COD and DOC were higher for the FE leachate.

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2393 ◽  
Author(s):  
Mehmood ◽  
Rehman ◽  
Wang ◽  
Farooq ◽  
Mahmood ◽  
...  

Physicochemical treatment, consisting of a combination of primary settling, coagulation–flocculation-aided clarification (alum, lime and magnesium sulfate as coagulants) and activated carbon adsorption, was employed for the treatment of pulp and paper mill wastewater. Treatability studies were undertaken to assess the feasibility of recycling the effluents from a paper mill. The results of laboratory scale investigation showed that the hydraulic retention time (HRT) of four hours for plain settling was effective to reduce 30% of the pollution load from pulp and board mill wastewater (PBMWW). The chemical secondary treatment reduced turbidity (89%), Chemical Oxygen Demand (84%), total suspended solids (90%) and color (89%) at the mass loading of 3400 mgl-1 of magnesium sulfate (MgSO4), when primary-treated effluent was subsequently treated by the coagulation–flocculation process. The combination of primary settling and lime coagulation (optimum dosage of 1400 mgl-1) resulted in a turbidity removal of 94%, a COD (Chemical Oxygen Demand) reduction of 86%, a Total Suspended Solids (TSS) removal of 93% and color removal of 91.6% at an initial pH of 11. The combination of this primary settling and coagulation–flocculation treatment trial indicated that the pollutant reduction efficiency of alum was better than the other two coagulants (MgSO4, lime), because the plain settling and coagulation–flocculation process with alum (optimum dosage of 1200 mg/L) resulted in a turbidity removal of 98%, COD reduction of 93%, TSS removal of 98% and color removal of 96% at the pH 6.0 with the sludge volume index of 156 mg/L. This chemically-treated water required further treatment with activated carbon in a batch reactor for up to four hours to meet the paper mill water quality standards. Pollutant reductions at the rate of 99.5%, 99.1%, 99.4% and 99.5% were obtained for turbidity, COD, TSS and color, respectively, with the combination of the sedimentation, coagulation–flocculation process and activated carbon adsorption meeting the production process quality standards. The study revealed that a hybrid end-of-pipe physicochemical treatment was effective in reducing the pollutant load of paper mills effluent and meeting the discharging standards.


1999 ◽  
Vol 40 (4-5) ◽  
pp. 435-442 ◽  
Author(s):  
Giovanni Bergna ◽  
Roberto Bianchi ◽  
Francesca Malpei

The paper presents the results obtained at laboratory, pilot and demonstrative scale with granular activated carbon adsorption as a mean to obtain effluent suitable as water supply for textile finishing industries, that require very stringent limits in terms of COD and colour removal. Laboratory scale tests evidenced that the specific carbon adsorption capacity, both for COD and colour, is highest for a sand-filtered + clariflocculated effluent and lowest for the sand-filtered + ozonated secondary effluent. Pilot and demonstrative scale tests were performed on three filters (0.3, 0.3 and 20 m3 of GAC each) fed with the full scale ozonated secondary effluent.


2007 ◽  
Vol 9 (4) ◽  
pp. 107-110 ◽  
Author(s):  
Bożena Seredyńska-Sobecka ◽  
Maria Tomaszewska

The influence of ozonation on the activated carbon adsorption of phenol and humic acid To study the influence of ozonation on the activated carbon adsorption, a model solution containing approximately 8 mg/dm3 of humic acid and approximately 1 mg/dm3 of phenol has been ozonated, and then adsorption kintetics and adsorption isotherm experiments have been performed. The applied ozone doses ranged from 1 to 3 mg O3/dm3, and a contact time was 1 min. In the adsorption experiments, the commercial activated carbon CWZ-30 (Gryfskand Sp. z o.o., Hajnówka, Poland) has been used. Phenol adsorption under equilibrium conditions was determined by the Freundlich isotherm equation, and the modified Freudlich isotherm equation has been employed for the determination of humic acid equilibrium adsorption. The applied oxidation conditions resulted in color, chemical oxygen demand (COD), total organic carbon (TOC) and UV254 absorbance removal, by 4 - 13%, 3 - 6%, 3 - 7%, respectively. After ozonation, phenol concentration decreased by 6 - 23%. These changes in the model solution did not affect the humic acid adsorption, however, they deteriorated phenol adsorption.


2019 ◽  
Vol 1 (2) ◽  
pp. e1128 ◽  
Author(s):  
David M. Kempisty ◽  
R. Scott Summers ◽  
Gulizhaer Abulikemu ◽  
Niranjan V. Deshpande ◽  
Jacob A. Rebholz ◽  
...  

2019 ◽  
Vol 4 (1) ◽  
pp. 1-10
Author(s):  
Aida Isma M.I. ◽  
◽  
Abdo Saad ◽  
Rachid Ali A. ◽  
Kenneth Yeoh ◽  
...  

Combined granular activated carbon adsorption with membrane filtration for high strength wastewater treatment have been carried out. Raw oleo-chemical wastewater and leachate were used as sample. Ultrafiltration is also relatively low cost, easy to backwash and operates up to 3 barg. Experiment was carried out by passing through the sample to an adsorption column for 10 minutes followed by membrane filtration at different transmembrane pressure of 1, 2 and 3 barg. Oleo-chemical samples were analysed for chemical oxygen demand, turbidity, suspended solid and leachate samples were analysed for chemical oxygen demand and ammonia nitrogen according to APHA method. Results showed that the best chemical oxygen demand, suspended solids and turbidity removal for oleo-chemical samples achieved at 2 bar with 64%, 93% and 97%, respectively. Leachate showed the best removal of chemical oxygen demand and ammonia nitrogen achieved at 3 bar, with 76% and 87%, respectively. The adsorption process combined with membrane filtration is feasible as an alternative for conventional biological treatment for high strength wastewater. However, GAC exhaustive breakthrough point requires monitoring.


Author(s):  
Xiaodong Dai ◽  
Jian Fang ◽  
Lei Li ◽  
Yan Dong ◽  
Jianhua Zhang

The wastewater produced from the oilfield is chemically corrosive due to high salinity in combination with high temperatures. It is also rich in contaminants, such as oil, polyacrylamide, emulsions, suspended solid, etc. The density difference between the oil and water in the wastewater is low, which makes separation via gravity difficult. In this study, a combined pilot treatment is studied, which includes Fenton oxidation, settlement, activated carbon adsorption, and ultrafiltration (UF). The operational conditions of Fenton oxidation are optimized based on alleviating the fouling of the UF membrane. When the Fenton oxidation was operated at the molar ratio of H2O2 to FeSO4 3:1 and pH 2.2–2.5, the UF membrane could operate continuously for 20 h without cleaning. The membrane was fouled by the organics (oil/grease) and polymer, which can be effectively removed by composite cleaning reagent consisting of 0.1% NaOH and 0.1% sodium dodecylbenzenesulfonate (SDBS). With the UF treatment, the chemical oxygen demand (COD) of the effluent was less than 50 mg/L, which could meet the upgraded standard.


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