ملخص البحث :

ملخص البحث :

In this study, a new multi-criteria decision analysis (MCDA) framework was designed and adopted for assessing the sustainability of solid waste treatment techniques (six treatment techniques) in urban areas of Baghdad (the capital of Iraq). A questionnaire has been developed that contains the four dimensions of sustainability (environmental, economic, social, and technical) and their indicators. These indicators have been studied, analyzed, and evaluated by a group of specialists working on solid waste management. Then the data were modelled adopting the weighted sum model (WSM), weighted product model (WPM) and technique for order preference by similarity to ideal solution (TOPSIS). The main results of the study clearly showed that the sustainability of municipal solid waste treatment in the city of Baghdad is directly related to the four dimensions in variable proportions (weights), and the environmental dimension gained the largest impact (46.9%) while the technical dimension gained the least impact (16.1%) on sustainability. By analyzing the questionnaire data according to the designed framework with reference to the three methods of MCDA (WSM, WPM, and TOPSIS) and in the presence of three Scenarios of the multi-criteria weights, Recycling by Source-Separation (RSS) Technique gained the highest score (0.896) which means that it is the best alternative, while Anaerobic Digestion Technique (AD) gained the lowest score (0.397) which means that it is the worst alternative, other scores are (0.874) for material recycling facility (MRF) Technique, (0.84) for Landill Technique, (0.813) for Composting Technique, and (0.584) for mass-burn incineration (MBI) Technique.

ملخص البحث :

The Great Al-Mussaib channel (GMC), in Babylon province, Iraq, has been selected as a case study to measure the concentration of nine heavy metals (Pb, Ni, Zn, Fe, Cd, Cr, Cu, Mn and Co) in both water and sediments of the GMC. The channel is used as a raw water source for two cities, which reveals the importance of the current study. Where, any heavy metals pollution could cause significant health problems for the population of these cities. The obtained results revealed that the concentrations of the studied heavy metals in the water of the GMC were less than the pollution levels and followed the order: Pb < Ni < Cu < Cr < Mn < Zn < Fe. It is noteworthy to highlight that the concentrations of Co and Cd were below the detectable limits. Additionally, the results obtained from the analyses of the studied sediment samples showed, according to the values of pollution load index and geo-accumulation index (I ), that the concentrations of studied metals were less than the pollution levels (except for a few cases) and followed the order: Cd < Co < Cu < Pb < Ni < Cr < Zn < Mn < Fe.

ملخص البحث :

An investigation into two non-toxic natural coagulants abundantly growing in different countries, cactus (Opuntia spp.) and okra was performed on monthly river water samples (one-year period). The studied case was the Euphrates river/Al-Mashroo canal/Iraq. Six statistical models were interpreted and tested describing the residual turbidity after Coagulation-Flocculation for the three studied cases (Optimum-Coagulant-Dose, Optimum-Flocculator-Velocity-Gradient and Optimum-Flocculation-Time). According to the environmental parameters recorded during the study and the statistical analyses, two facts were concluded. The first fact was that controlling the Optimum-Flocculator-Velocity-Gradient of the Coagulation-Flocculation process gave the highest contribution ratio of the models. The second fact was that the most significant environmental parameter (statistically) in the Coagulation-Flocculation process was the initial turbidity. This was proved for the two natural coagulants under study. Also, from the results of the study, it was concluded that the two natural coagulants were of similar coagulation-flocculation properties, and they were competent for turbidity removal.

ملخص البحث :

A batch leaching test was performed to measure the leached concentrations of chromium (Cr), lead (Pb), arsenic (As), nickel (Ni), copper (Cu), cadmium (Cd), and zinc (Zn) from dredged sediment samples from the Leeds & Liverpool canal/ Liverpool section. The obtained results confirmed that the leached concentrations of the studied heavy metals were less than the toxicity levels and followed the order: Zn > Cu > Ni > Pb > Cr > As > Cd. The highest concentration was of Zn (about 0.28 mg/L), followed by Cu at a concentration of 0.17 mg/L, while the lowest concentration was of Cd at 0.009 mg/L. Therefore, the dredged sediments from this canal can be safely relocated in dumping sites such as landfills, or reused such as by spreading on agricultural fields.

ملخص البحث :

This study investigates the influence of the current density on both removal of reactive black 5 dye (RB5) from water and energy consumption using aluminium-based electrocoagulation (EC) reactor. The influence of the current density was investigated by electrolysing coloured water samples containing 25 mg/l of RB5 for 60 min at three different current densities (1, 2, and 3 mA/cm2). While the initial pH, distance between electrodes, flow rate, and initial temperature of water were kept constant at 5, 4 mm, 1 L/h, and 20 ± 10C, respectively. The obtained results showed that both the removal of RB5 dye and energy consumption increased with the increase of the applied current density. For example, it has been found that the removal RB5 and the power consumption increased from about 95% to 99.5%, and the power consumption increased from 4.3 to 10.4 kWh/m3 as the current density increased from 1 to 3 mA/cm2, respectively.