Shuokr Qarani Aziz

Leachate characterization in semi-aerobic and anaerobic sanitary landfills: A comparative study

This study analyzes and compares the results of leachate composition at the semi-aerobic Pulau Burung Landfill Site (PBLS) (unaerated pond and intermittently aerated pond) and the anaerobic Kulim Sanitary Landfill in the northern region of Malaysia. The raw samples were collected and analyzed for twenty parameters. The average values of the parameters such as phenols (1.2, 6.7, and 2.6 mg/L), total nitrogen (448, 1200, and 300 mg/L N-TN), ammonia-N (542, 1568, and 538 mg/L NH(3)-N), nitrite (91, 49, and 52 mg/L NO(2)(-)-N), total phosphorus (21, 17, and 19 mg/L), BOD(5) (83, 243, and 326 mg/L), COD (935, 2345, and 1892 mg/L), BOD(5)/COD (0.096,0.1124,0.205%), pH (8.20, 8.28, and 7.76), turbidity (1546, 180, and 1936 Formazin attenuation units (FAU)), and color (3334, 3347, and 4041 Pt Co) for leachate at the semi-aerobic PBLS (unaerated and intermittently aerated) and the anaerobic Kulim Sanitary Landfill were recorded, respectively. The obtained results were compared with previously published data and data from the Malaysia Environmental Quality Act 1974. The results indicated that Pulau Burung leachate was more stabilized compared with Kulim leachate. Furthermore, the aeration process in PBLS has a considerable effect on reducing the concentration of several pollutants. The studied leachate requires treatment to minimize the pollutants to an acceptable level prior to discharge into water courses.

Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH(3)-N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1L/min and contact time of 5.5h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH(3)-N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

Stabilized sanitary landfill leachate treatment using anionic resin: treatment optimization by response surface methodology.

The treatability of stabilized sanitary landfill leachate via synthetic anion exchange resin (INDION FFIP MB) was investigated. An ideal experimental design was conducted based on central composite design using a response surface methodology to assess individual and interactive effects of critical operational variables (i.e., anionic dosage; contact time; shaking speed) and pH on treatment performance in terms of color, chemical oxygen demand (COD), suspended solid (SS), and turbidity removal efficiencies. Optimum operational conditions were established as 30.9 cm(3) anionic dosage, 90 min contact time, 150 rpm shaking speed, and pH 3.1. Under these conditions, the color, COD, SS, and turbidity removal efficiencies of 91.5, 70.3, 93.1, and 92.4% were experimentally attained and were found to fit well with the prediction model. According to these results, stabilized leachate treatment using INDION FFIP MB could be an effective alternative in the administration of color, COD, SS, and turbidity problems of landfill leachates.

An overview of electro-oxidation processes performance in stabilized landfill leachate treatment

Abstract Among numerous techniques, electro-oxidation occupies a noticeable place in landfill leachate treatment. In recent years, electro-oxidation processes have been shown to be effective alternative for the removal of refractory organic compounds from stabilized landfill leachate. This paper aims to provide an overview about the effectiveness and mechanism of electro-oxidation processes employed for stabilized landfill leachate treatment. A review of the recent literature published on the electro-oxidation processes (i.e. electrochemical, electro-Fenton, photoelectro-Fenton, photoelectrochemical, and electrochemical peroxidation) performance and efficiency in stabilized leachate treatment are summarized and presented in this study. This study concluded that, although the high treatment cost caused by the energy consumption may limit electro-oxidation techniques, electro-oxidation processes are still a promising and effectual technology for the reduction of pollutants in stabilized landfill leachate.

Powdered ZELIAC augmented sequencing batch reactors (SBR) process for co-treatment of landfill leachate and domestic wastewater.

Sequencing batch reactor (SBR) is one of the various methods of biological treatments used for treating wastewater and landfill leachate. This study investigated the treatment of landfill leachate and domestic wastewater by adding a new adsorbent (powdered ZELIAC; PZ) to the SBR technique. ZELIAC consists of zeolite, activated carbon, lime stone, rice husk ash, and Portland cement. The response surface methodology and central composite design were used to elucidate the nature of the response surface in the experimental design and describe the optimum conditions of the independent variables, including aeration rate (L/min), contact time (h), and ratio of leachate to wastewater mixture (%; v/v), as well as their responses (dependent variables). Appropriate conditions of operating variables were also optimized to predict the best value of responses. To perform an adequate analysis of the aerobic process, four dependent parameters, namely, chemical oxygen demand (COD), color, ammonia-nitrogen (NH3-N), and phenols, were measured as responses. The results indicated that the PZ-SBR showed higher performance in removing certain pollutants compared with SBR. Given the optimal conditions of aeration rate (1.74 L/min), leachate to wastewater ratio (20%), and contact time (10.31 h) for the PZ-SBR, the removal efficiencies for color, NH3-N, COD, and phenols were 84.11%, 99.01%, 72.84%, and 61.32%, respectively.

Metals removal from municipal landfill leachate and wastewater using adsorbents combined with biological method

Different physical, chemical, and biological treatment methods are used to eliminate heavy metals and pollutants from wastewater and landfill leachate. Sequencing batch reactor (SBR) is a type of biological treatment. This study was conducted to study heavy metals elimination from urban wastewater and landfill leachate using an adsorbent, namely powdered ZELIAC (PZ) that improved SBR. PZ consists of portland cement, limestone, rice husk ash, activated carbon, and zeolite. Response surface methodology and central composite design were used to elucidate the nature of the response surface in the experimental plan and determine the optimum settings of the independent variables [aeration rate (L/min), contact time (h), and leachate to wastewater ratio (%; v/v)] and their reactions. To study the aerobic process, four dependent factors (Fe, Mn, Ni, and Cd) were evaluated as reactions. The results indicated that compared with SBR, PZ-SBR removed heavy metals more efficiently. At the optimum contact time (11.70 h), aeration rate (2.87 L/min), and leachate to wastewater ratio (20.13%) in PZ-SBR, removal efficiencies for Fe, Mn, Ni, and Cd were 79.57, 73.38, 79.29, and 76.96%, respectively.

Optimum Process Parameters for the Treatment of Landfill Leachate Using Powdered Activated Carbon Augmented Sequencing Batch Reactor (SBR) Technology

The sequencing batch reactor (SBR) process was used for the treatment of raw landfill leachate. Optimum preliminary parameters of leachate/activated sludge ratio, powdered activated carbon (PAC) dosage, and settling time were studied. Optimum obtained parameters (mixing ratio of 10%, PAC dosage of 10 g/L, and settling time of 1.5 h) were applied on two types of SBRs, namely, non-powdered and powdered activated carbon (NPAC and PAC, respectively). Consequently, the effect of factors, the aeration rate and contact time, on both NPAC and PAC reactors were studied. Response surface methodology was used for the design, analysis, and optimization of the experiments. Removal efficiencies of ammonia (NH3-N), color, chemical oxygen demand (COD), total dissolved salts (TDS), and sludge volume index (SVI) were measured for 13 experiments. Based on the obtained results, the optimum aeration rate and contact time for both NPAC and PAC reactors were 2 and 1 L/min and 5.56 and 5.5 h, respectively. Better performance (in terms of NH3-N, color, COD, and TDS removal efficiencies and SVI values) was exhibited by PAC reactors rather than NPAC.

Adsorption isotherms in landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor technique: Statistical analysis by response surface methodology

Abstract Landfill leachate was treated using non-powdered activated carbon sequencing batch reactor (NPAC-SBR) and powdered activated carbon (PAC) augmented SBR (PAC-SBR) processesto examine Langmuir and Freundlichadsorption isothermsin the SBR technique.Response surface methodology (RSM) was used for the experimental design and statistical analysis.Based on the obtained results, the maximum adsorption capacitiesof ammonia nitrogen (NH3-N), color, and chemical oxygen demand (COD) for the Langmuir adsorption isotherm were 5.63 mg/g, 25.30 Pt.Co/g, and 13.21 mg/g,respectively, whereas for the Freundlichadsorption isotherm, thesewere 6 mg/g, 46.29Pt.Co/g, and 15.41 mg/g, respectively.Generally, Freundlich isotherm values for NH3-N, color, and COD were higher than Langmuir isotherm values.The NH3-N adsorption on PAC was lower than the color and COD adsorptions because a great part of NH3-Nwas biologically removed in the SBR process.Increasing aeration rate and contact times in the SBR processes increased the adsorption isotherms of NH3-N, color, and COD on PAC

Application of Response Surface Methodology to Enhance Phenol Removal from Refinery Wastewater by Microwave Process

Phenol contaminated petroleum refinery wastewater presents a great threat on water resources safety. This study investigates the effect of microwave irradiation on removal of different concentrations of phenol in an attempt for petroleum refinery wastewater treatment. The obtained results show that the MW output power and irradiation time have a significant positive effect on the removal efficiency of phenol. The kinetic reaction is significantly affected by initial MW output power and initial phenol concentrations. Response surface methodology (RSM) was employed to optimize and study the interaction effects of process parameters: MW output power, irradiation time, salinity, pH, and H2O2 concentration using central composite design (CCD). From the CCD design matrix, a quadratic model was considered as an ultimate model (2 = 0.75) and its adequacy was justified through analysis of variance (ANOVA). The overall reaction rates were significantly enhanced in the combined MW/H2O2 system as proved by RSM. The optimum values for the design parameters of the MW/H2O2 process were evaluated giving predicted phenol removal percentage of 72.90% through RSM by differential approximation and were confirmed by experimental phenol removal of 75.70% in a batch experiment at optimum conditions of 439 W MW power, irradiation time of 24.22 min, salinity of 574 mg/L, pH 5.10, and initial H2O2 concentration of 10% (v/v).

Appraisal of domestic solid waste generation, components, and the feasibility of recycling in Erbil, Iraq:

Solid waste collection and disposal are among the most vital services provided to about 700 770 residents of the city of Erbil in northern Iraq. As such, proper waste management systems that consider both the quantity and composition of domestic solid waste are strongly required to address the increasing amount of solid waste. Unfortunately, these essential data are not easily available. The present study sought to gather data on the quantity and composition of domestic solid waste collected from different quarters in Erbil, and the feasibility of recycling these wastes. The solid waste generation rate (GR), uncompacted density, and weight percentages of combustible and incombustible materials were determined based on the collected materials (i.e., food, plastic, paper, metal, glass and cloth). The results show that the average GR and uncompacted density were 0.654 kg capita(-1) day(-1) and 175.72 kg m(-3), respectively. The weight percentages of food, plastic, paper, metal, glass, and cloth as components of domestic solid waste were 79.34, 6.28, 5.9, 3.6, 3.42 and 1.45%, respectively.Solid waste collection and disposal are among the most vital services provided to about 700 770 residents of the city of Erbil in northern Iraq. As such, proper waste management systems that consider both the quantity and composition of domestic solid waste are strongly required to address the increasing amount of solid waste. Unfortunately, these essential data are not easily available. The present study sought to gather data on the quantity and composition of domestic solid waste collected from different quarters in Erbil, and the feasibility of recycling these wastes. The solid waste generation rate (GR), uncompacted density, and weight percentages of combustible and incombustible materials were determined based on the collected materials (i.e., food, plastic, paper, metal, glass and cloth). The results show that the average GR and uncompacted density were 0.654 kg capita(-1) day(-1) and 175.72 kg m(-3), respectively. The weight percentages of food, plastic, paper, metal, glass, and cloth as components of domestic solid waste were 79.34, 6.28, 5.9, 3.6, 3.42 and 1.45%, respectively.