Preparation of artificial MSW leachate for treatment studies: Testing on black soldier fly larvae process

When approaching the study of new processes for leachate treatment, each influencing variable should be kept under control to better comprehend the treatment process. However, leachate quality is difficult to control as it varies dramatically from one landfill to another, and in line with landfill ageing. To overcome this problem, the present study investigated the option of preparing a reliable artificial leachate in terms of quality consistency and representativeness in simulating the composition of real municipal solid waste (MSW) leachate, in view of further investigate the recent treatment process using black soldier fly (BSF) larvae. Two recipes were used to simulate a real leachate (RL): one including chemical ingredients alone (artificial synthetic leachate-SL), and the other including chemicals mixed with artificial food waste (FW) eluate (artificial mixed leachate-ML). Research data were analysed, elaborated and discussed to assess simulation performance according to a series of parameters, such as Analytical representativeness, Treatment representativeness (in this case specific for the BSF larvae process), Recipe relevance, Repeatability and Flexibility in selectively modifying individual quality parameters. The best leachate simulation performance was achieved by the synthetic leachate, with concentration values generally ranging between 97% and 118% of the RL values. When feeding larvae with both RL and SL, similar mortality values and growth performance were observed.

Effects of selection and compiling strategy of substrates in column-type vertical-flow constructed wetlands on the treatment of synthetic landfill leachate containing bisphenol A

A constructed wetland (CW) is a low-cost, eco-friendly, easy-to-maintain, and widely applicable technology for treating various pollutants in the waste landfill leachate. This study determined the effects of the selection and compiling strategy of substrates used in CWs on the treatment performance of a synthetic leachate containing bisphenol A (BPA) as a representative recalcitrant pollutant. We operated five types of lab-scale vertical-flow CWs using only gravel (CW1), a sandwich of gravel with activated carbon (CW2) or brick crumbs (CW3), and two-stage hybrid CWs using gravel in one column and activated carbon (CW4) or brick crumbs (CW5) in another to treat synthetic leachate containing BPA in a 7-d sequential batch mode for 5 weeks. CWs using activated carbon (CW2 and CW4) effectively removed ammonium nitrogen (NH4-N) (99–100%), chemical oxygen demand (COD) (93–100%), and BPA (100%), indicating that the high adsorption capacity of activated carbon was the main mechanism involved in their removal. CW5 also exhibited higher pollutant removal efficiencies (NH4-N: 94–99%, COD: 89–98%, BPA: 89–100%) than single-column CWs (CW1 and CW3) (NH4-N: 76–100%, COD: 84–100%, BPA: 51–100%). This indicates the importance of the compiling strategy along with the selection of an appropriate substrate to improve the pollutant removal capability of CWs.

Aerobic Attached Growth Biofilter Using Tire Chips And Mixed Broken Glass As Media For Landfill Leachate Treatment

Ontario regulations can necessitate expensive leachate treatment plants in large landfills. Lower-cost technologies may suit rural landfills due to lower waste toxicity and less proximity to residents. One low-cost technology is a trickling filter using tire chips or mixed broken glass (MBG) as filter media instead of non-renewable aggregate. Aerobic fixed-bed reactors using river-rock gravel, crushed rock, tire chips,and MBG as filter media were compared. COD treatment of stabilized leachate in Phase 1 was limited (max. 21%). Activated sludge was added in Phase 2, and MGB removed 30% COD, 88% BOD₅, 38% NH₃-N, 99% BOD₅, and 90-98% TSS from a stronger synthetic leachate. NH₃-N removal improved, while TS removal remained limited. All media types performed similarly, suggesting that tire chips and MBG could be used to treat low-to-medium-strength leachate in a trickling filter.

Aerobic Attached Growth Biofilter Using Tire Chips And Mixed Broken Glass As Media For Landfill Leachate Treatment

Ontario regulations can necessitate expensive leachate treatment plants in large landfills. Lower-cost technologies may suit rural landfills due to lower waste toxicity and less proximity to residents. One low-cost technology is a trickling filter using tire chips or mixed broken glass (MBG) as filter media instead of non-renewable aggregate. Aerobic fixed-bed reactors using river-rock gravel, crushed rock, tire chips,and MBG as filter media were compared. COD treatment of stabilized leachate in Phase 1 was limited (max. 21%). Activated sludge was added in Phase 2, and MGB removed 30% COD, 88% BOD₅, 38% NH₃-N, 99% BOD₅, and 90-98% TSS from a stronger synthetic leachate. NH₃-N removal improved, while TS removal remained limited. All media types performed similarly, suggesting that tire chips and MBG could be used to treat low-to-medium-strength leachate in a trickling filter.

Morphological modification of low-density polyethylene for enhanced Phanerochaete chrysosporium surface bioerosion

Disposal of end-of-life low density polyethylene (LDPE) in landfill structures poses an ecological threat through leaching, fragmentation, and additive migration. The present study examines the mycodegradation of morphologically modified low- density polyethylene (LDPE) films by Phanerochaete chrysosporium, a lignolytic basidiomycete. Three physicochemical treatments were employed: thermo-oxidation, chemical etching, and synthetic leachate. Surface area imaging over 6 days revealed bioerosion, qualifying P. chrysosporium as a suitable agent for LDPE degradation. Analysis of crystallinity indices showed that thermo-oxidation and chemical etching induced conformational changes to the polymer surface, increasing surface area reduction by 19% and 22% respectively. Synthetic leachate (SL) was associated with a 36% increase in surface area reduction. In combination, the three treatments achieved a 99% increase in surface area reduction. These trends were corroborated by gaseous evolution in parallel, attributable to the metabolization of fungal isolates. Electrospray Ionization Fourier Transform (FTMS + pESI) profiles observed signs of leachate remediation and organic byproducts. A molecular mechanism for degradation was subsequently proposed based on SL composition.

Treatability tests of synthetic leachate from the Al-Hoceima city controlled landfill

Due to population growth and the intensification of economic activity, the production of solid waste is constantly increasing in Morocco [1]. Several programs consist of the establishment of controlled landfills and the rehabilitation of uncontrolled landfills. The impact of landfilling is the production of liquid effluents rich in organic, mineral, and metallic matter called leachate [2,3]. The choice of leachate treatment is based on the characteristics of the leachate. Any treatment process has advantages and limitations, so before proceeding with the treatment it is necessary to characterize the leachate to choose the appropriate process [11]. The objective of this study is to prepare synthetic leachate based on the characteristics of real leachate (case of the controlled landfill of Al Hoceima), in order to carry out treatability tests of this synthetic leachate by controlling the various parameters of analysis. This solution was made from organic (CH3CO2H, CH3CO2Na) and inorganic compounds (MgSO4, CaCl2, Ca(OH)2, NH4Cl, KOH, MgCl2), the various analyzes of this solution gave values comparable to the real solution. This work was devoted to carrying out the treatability tests of synthetic leachate by a process of adsorption on bentonite, by studying its yield to reduce the organic load.