Environmental pollution size of the Bishkek Solid Waste Landfill and treatment of generated leachate wastewater
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2021-08-10 |
| Journal | MANAS Journal of Engineering |
| Authors | Venera EDÄ°LBEK KYZY, Nurzat Shaykieva, Kubat Kemelov, Mustafa Dolaz, Mehmet Kobya |
| Institutions | Kyrgyz-TĂŒrkish Manas Ăniversity |
| Citations | 2 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: High-Performance BDD Anodes for Electro-Oxidation of Refractory Leachate
Section titled âTechnical Documentation & Analysis: High-Performance BDD Anodes for Electro-Oxidation of Refractory LeachateâExecutive Summary
Section titled âExecutive SummaryâThis research validates the critical role of Boron-Doped Diamond (BDD) anodes in achieving superior environmental remediation outcomes, specifically for treating highly recalcitrant landfill leachate via Electro-Oxidation (EO).
- Application Validation: The EO process utilizing BDD anodes proved highly effective for treating stabilized landfill leachate, a notoriously difficult wastewater stream.
- Material Performance: BDD anodes achieved near-complete mineralization, demonstrating removal efficiencies of 97.9% for COD, 95.5% for TOC, and 99.8% for Ammonia Nitrogen at optimal current densities.
- Refractory Pollutant Destruction: The study confirms BDDâs capability to generate highly reactive hydroxyl radicals (âąOH), leading to the rapid and indiscriminate destruction of nonbiodegradable and toxic organic compounds.
- Process Superiority: EO using BDD significantly outperformed the conventional Coagulation-Flocculation (CF) pretreatment, which achieved maximum COD removal of only 40%.
- Scalability and Efficiency: The EO process offers key advantages over CF, including high oxidation efficiency, amenability to automation, minimal chemical addition, and the absence of secondary treatment sludge.
- 6CCVD Value Proposition: 6CCVD is an expert supplier of custom, high-quality BDD films and plates, essential for replicating and scaling this high-current-density electrochemical application.
Technical Specifications
Section titled âTechnical SpecificationsâThe following table summarizes the key operational parameters and performance metrics achieved using the Boron-Doped Diamond (BDD) anode in the Electro-Oxidation (EO) reactor.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Anode Material | Boron-Doped Diamond (BDD) | Plate | Grown on Niobium substrate |
| Cathode Material | Stainless Steel (SS) | Plate | Used as counter electrode |
| Electrode Dimensions | 20 x 6 | cm | Total area of 120 cm2 per electrode |
| Electrode Gap | 1.60 | cm | Parallel plate configuration |
| Maximum Applied Current | 5.0 | A | Constant current condition |
| Maximum Current Density | 208.33 | A/m2 | Achieved at 5.0 A |
| Reaction Time (Max) | 260 | min | Time required for maximum removal |
| Initial COD Concentration | 1400 ± 50 | mg/L | Characteristics of Bishkek Landfill Leachate (BLL) |
| Maximum COD Removal | 97.90 | % | Achieved at 5.0 A |
| Maximum TOC Removal | 95.53 | % | Achieved at 5.0 A |
| Maximum NH3-N Removal | 99.8 | % | Achieved at 5.0 A |
| Operating Temperature | 22 ± 3 | °C | Room temperature operation |
Key Methodologies
Section titled âKey MethodologiesâThe Electro-Oxidation (EO) experiments were conducted in a batch reactor using 1000 mL of landfill leachate. The methodology highlights the precise material and operational control required for high-efficiency wastewater treatment:
- Electrode Configuration: A BDD plate anode (on Niobium substrate) and a Stainless Steel (SS) plate cathode were arranged parallel to each other with a fixed gap of 1.60 cm. Both electrodes measured 20 x 6 cm (120 cm2 area).
- Power Supply: A direct current (dc) power supply (GW Instek, GPD-4303S) was used to maintain constant current conditions throughout the experiment.
- Current Density Variation: Experiments were performed at three specific applied current intensities: 1.0 A (41.67 A/m2), 3.0 A (125 A/m2), and 5.0 A (208.33 A/m2).
- pH Control: The pH was adjusted using concentrated H2SO4 or NaOH solutions, although the paper notes the process was conducted without the addition of a background electrolyte.
- Mixing: The leachate within the reactor was continuously mixed using a magnetic stirrer (Daigger model) to ensure homogeneity.
- Sampling and Analysis: Leachate samples were periodically collected, filtered (0.45 ”m microspore membrane filter), and analyzed for COD, TOC, and NH3-N according to Standard Methods.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful application of BDD anodes in this high-performance EO study underscores the need for high-quality, customizable diamond materials. 6CCVD is uniquely positioned to supply the necessary components for replicating, scaling, and optimizing this research for industrial deployment.
Applicable Materials
Section titled âApplicable MaterialsâTo achieve the high current densities and robust chemical stability required for effective leachate treatment, 6CCVD recommends the following materials:
- Heavy Boron-Doped Diamond (BDD) Plates: Essential for high-efficiency Advanced Oxidation Processes (AOPs) like EO. Our BDD films offer the wide potential window and high anodic stability necessary for generating hydroxyl radicals and achieving complete mineralization of refractory organics and ammonia.
- Custom Substrates: The paper utilized BDD on Niobium. 6CCVD offers BDD deposition on various conductive substrates, including Titanium (Ti), Tungsten (W), and Niobium (Nb), optimized for electrochemical stability and conductivity in aggressive environments.
Customization Potential
Section titled âCustomization Potentialâ6CCVDâs MPCVD capabilities directly address the specific engineering requirements of industrial EO reactor design:
| Requirement from Research | 6CCVD Custom Capability | Benefit to Client |
|---|---|---|
| Specific Plate Dimensions (20 x 6 cm) | Custom dimensions up to 125mm wafers/plates. | Allows for precise scaling and optimization of electrode surface area (A/m2) for pilot or industrial reactors. |
| BDD Film Thickness | SCD/PCD thickness from 0.1 ”m to 500 ”m. | Tailored film thickness ensures longevity and performance stability under high current density (up to 208 A/m2). |
| Substrate Integration | Custom metalization (Ti, W, Cu, Pt, Au, Pd) and bonding preparation. | Ensures low contact resistance and robust mechanical integration of the BDD film onto the conductive current collector. |
| High Surface Finish | Polishing capability (Ra < 1nm for SCD). | While not critical for BDD activity, high-quality polishing ensures uniform film growth and minimizes defects that could lead to premature failure. |
| Global Supply Chain | Global shipping (DDU default, DDP available). | Reliable, fast delivery of specialized diamond electrodes worldwide for time-sensitive research and development projects. |
Engineering Support
Section titled âEngineering SupportâThe successful implementation of BDD technology requires deep material science expertise. 6CCVDâs in-house PhD team specializes in electrochemical applications and can provide comprehensive support:
- Material Selection Consultation: Assistance in selecting the optimal boron doping level and film morphology (SCD vs. PCD) to maximize current efficiency and minimize energy consumption for similar Leachate Treatment and Industrial Wastewater projects.
- Design Optimization: Guidance on electrode geometry, substrate choice, and metalization schemes to ensure maximum operational lifespan and performance stability in highly corrosive media.
- Process Extension: Support for researchers looking to extend this work to flow-through reactors or other AOPs (e.g., ozone generation, electrochemical disinfection).
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
The disposal of municipal solid wastes (MSW) is one of the important issues today. The MSW is generally disposed of in a landfill. The disintegration of wastes in landfill generates the wastewater known as leachate and it became one of the budding environmental impacts. The landfill leachate seeps into natural ponds next to the Bishkek (Kyrgyzstan) landfill. The MSWs are dumped with an irregular landfill in Bishkek, and it has been observed that this situation creates many environmental pollution problems (air pollution due to the combustion of wastes and generated biogas, due to leakage of leachate from the landfill) around the landfill. The leachate in the ponds is not treated and leaks into the environment. In this study, the potential of the coagulation-flocculation(CF) and electrooxidation (EO) processes was investigated for the treatment of leachate from the sanitary landfill located in Bishkek-Kyrgyzstan. The initial COD (1400 ± 50 mg/L), TOC (540 ± 15 mg/L), and ammonia nitrogen (315 ± 10 mg/L) from landfill leachate were treated by the CF process as 33, 23, and 14% at pH 6.5 with alum dosage of 5 g/L, and 40, 29 and 10.1% at pH 8.5 with ferric chloride dosage of 5 g/L, respectively.Removal efficiencies at applied currents of 1.0, 3.0, and 5.0 A with an EO reactor using boron-doped diamond (BDD) plate anode and stainless steel (SS) plate cathode were 67.20, 88.30, and 97.90% for COD, 60.10, 85.38, and 95.53% for TOC, and 48.9, 94.6 and 99.8% for ammonia nitrogen, respectively. As a result, it was seen that Bishkekâs irregular solid waste landfilling leachate, which causes environmental pollution, was effectively treated with the EO process. By establishing a regular landfill, Bishkek municipal solid wastes must be disposed of in the landfill and treated of the leachate.