Effect of a geotextile filter on leachate quality in a recirculated landfill bioreactor

Abstract

a b s t r a c tLandfills cause various problems for local authorities, such as contamination of soil and water with toxins, the formation of leachate and the release of landfill gases. More economical and applicable innovative solutions to overcome these problems will be an advantage for local authorities. One of the problems that local authorities face during the operation of landfills is the cost of leachate treatment due to high energy consumption. The objective of this study is, with the use of two laboratory-scale anaerobic bioreactors, to improve leachate quality by using a polymeric geotextile (GT) material placed horizontally in the drainage layer of a lab-scale landfill bioreactor (LBR). The simulated LBR equipped with the geotextile filter (LBR-GT) achieved faster leachate quality improvement than the control reactor (LBR-C). Scanning electron microscope images showed that the GT filters allowed the biofilm to grow not only on the surface but also in the interior pores, which increased the interactions between the biomass and the organics. In this way, the leachate quality improved in a short time as a result of the high biomass growth in the GT filter. The chemical oxygen demand (COD), the 5-d biochemical oxygen demand (BOD 5 ), the pH, the oxidation reduction potential (ORP) and other operating parameters in the leachate were regularly monitored. The LBR-GT reached a -300 mV ORP value on the 54th day, while the LBR-C reached the same ORP value on the 145th day. After 208 d of anaerobic incubation, the removal rates for the COD and BOD 5 in LBR-C were 93% and 96%, respectively, whereas in the LBR-GT, the removal rates were 96% and 99%, respectively. The main result of this study was that the LBR-GT took only 90 d to reach 90% COD removal rate, whereas the LBR-C took 166 d to reach the same removal rate.

Community Structure of Bacteria and Archaea Associated with Geotextile Filters in Anaerobic Bioreactor Landfills

“…These bioreactor landfills also contained horizontally placed geotextile filters in their drainage layers as a biofilm medium for leachate treatment. The biomass-holding capacity of porous nonwoven geotextiles has been reported in the literature in detail [6,19,20]. In the current study, the diversity and composition of the bacterial and archaeal communities developed on geotextile filters placed in the drainage chamber of pilot-scale bioreactor landfills were examined after 540 days of anaerobic operation through the metagenomics approach.…”

“…Furthermore, 2 reactors (R-1 and R-2) contained solid waste and sewage sludge at a ratio of 1/20, respectively, while the other 2 reactors contained only solid waste. The effect of using geotextile layers on leachate quality in laboratory-scale and pilot-scale landfill bioreactors has been investigated in previous papers and is not included in this study [6,20].…”

Enhancement of landfill gas production and waste stabilisation by using geotextile filter in a bioreactor landfill

“…One promising method is to use a synthetic filter (geotextile filter) material in the drainage layer of the landfills to provide an environment for the growth of the anaerobic microorganisms. The geotextile filters, due to their high surface and internal area, can provide a suitable environment for the microorganisms (Küçükağa, 2016;Yaman et al, 2003;Yaman and Küçükağa, 2017;Yaman et al, 2005). Highly permeable geotextile materials are used as an infrastructure material in landfill areas across the world, mainly for protecting the impermeable geomembrane layer from the gravel and waste particles.…”

“…Various researchers have tried to enhance the LFG production rate in bioreactor landfills but using a geotextile biofilter in a simulated anaerobic bioreactor landfill was not tried, which is the focus of the present study. The first half of the work, which investigated the effect of geotextile filters on leachate quality in landfill bioreactors, has been published recently (Yaman and Küçükağa, 2017). It has been shown in the first half of the work that the simulated bioreactor equipped with the geotextile filter (LBR-GT) achieved faster leachate quality improvement than the control reactor (LBR-C).…”

Improvement of leachate quality and waste stabilization in pilot-scale bioreactor landfills containing geotextile filters and sewage sludge

“…The lab-scale version of the system tested in this current study investigated the effect of geotextile filter on leachate quality [19][20][21]. The dimensions of the lab-scale reactors were 1 m high and 30 cm diameter.…”