Efficiency of Combined Processes Coagulation/Solar Photo Fenton in the Treatment of Landfill Leachate

Abstract

The combined coagulation-solar photo Fenton treatment of leachate from the sanitary landfill located in Atlantico-Colombia was investigated. Firstly, the efficiency of two alternative combined treatments for the reduction of chemical oxygen demand in leachate was assessed, coagulation with poly-aluminum chloride followed by solar photo-Fenton process (Treatment 1) and coagulation with FeCl3·6H2O followed by ferrioxalate-induced solar photo-Fenton process (Treatment 2). Afterwards, treatments 1 and 2 were compared with the treatment currently used in the sanitary landfill (only coagulation with poly-aluminum chloride), in terms of efficiency and costs. An optimization study of alternative treatments was performed combining central-composite experimental design and response surface methodology. The optimum conditions resulted in a chemical oxygen demand reduction of 73 % and 80 % for Treatment 1 and 2, respectively. Both alternative treatments for the leachate are more efficient than the treatment currently used in the sanitary landfill (chemical oxygen demand reduction of 20 %). In terms of costs, treatment 1 would be the most competitive to implement in the sanitary landfill, since this would have an increase of 13.3 % in the total unitary cost compared to an increase of 39.5 % of treatment 2.

An Extensive Analysis of Combined Processes for Landfill Leachate Treatment

“…LL typically contains various challenging components such as recalcitrant and heat-resistant organic matter, toxic substances, suspended and colloidal solids, heavy metals, and humic substances [64,105]. Humic substances are large anionic molecules with different molecular weights, and LL often has a low ratio of BOD 5 /COD < 0.1 [149]. The presence of humic substances and non-degradable organic matter makes biological treatment processes less effective [149].…”

“…Humic substances are large anionic molecules with different molecular weights, and LL often has a low ratio of BOD 5 /COD < 0.1 [149]. The presence of humic substances and non-degradable organic matter makes biological treatment processes less effective [149]. Therefore, a combination of chemical processes is employed for the treatment of LL.…”

“…Rebolledo [149] conducted experiments to treat stabilized LL using two different combination treatments. The first treatment involved coagulation/sedimentation (C/S) with polyaluminum chloride (PAC), followed by the SPF process.…”

Optimization of the humic acid separation and coagulation with natural starch by RSM for the removal of COD and colour from stabilized leachate

“…The coefficient of determination along with adjusted R 2 assessed the models' capability in the fitting. Meanwhile, predicted R 2 and AP specify the prediction capability of the model (Rebolledo et al, 2019).…”

Combining Coagulation and Electrocoagulation with UVA-LED Photo-Fenton to Improve the Efficiency and Reduce the Cost of Mature Landfill Leachate Treatment

“…Although this is an old problem, there is not an accepted best treatment strategy for mature LL yet. Several authors [17][18][19] proposed the application of coagulation followed by photo-Fenton treatment, which achieved efficiencies of 60-89% depending on the coagulant used (polyaluminum chloride or ferric chloride) and the pH. Coagulation is based on the removal of organic matter by destabilization of colloids and particles due to charge neutralization, which produces their aggregation and facilitates their separation by sedimentation or flotation [20].…”