Document Type : Research Paper

Authors

1 The State Company for Glass and Refractories, the Ministry of Industry and Minerals(MIM), Ramadi, Iraq

2 Sadar Al-Iraq University, College of Engineering, Baghdad, Iraq

3 School of Science, Engineering and Design, Teesside University, Middleborough, The UK

4 Department of Civil Engineering, College of Engineering, University of Basrah, Basrah, Iraq

10.30772/qjes.2024.148635.1191

Abstract

This study examines the impact of mixing methods in enhancing the coagulation-flocculation process. Two types of coagulants: Aluminum Sulfate Hydrate [Al2(SO4)3.16H2O] and Magnesium Chloride [MgCl2] were used. The polymer polyacrylamide (C3H5n) was utilized as a flocculent aid. A fully baffled mixing tank agitated with retreat curve impellers rotates in the range of  as an increment step and a mixing time of  was used in the present study. The present investigation includes two methodologies: the first is based on numerical solutions using MIXSIM 2.0 and ANSYS Fluent, while the second is based on experimental work. The Kaolin particles were utilized to represent the suspension collides in natural raw water. The image analysis technique was used to determine the surface area of producing flocs. The results established that the most appropriate impeller rotational speed for the flocculation process is in the range of and for alum coagulants. The maximum surface area of the floc was found to be  produced at  with  of mixing time and the maximum final floc surface area was  at  and  of mixing time. For magnesium chloride coagulant the max surface area of floc was produced at  and  of mixing time, the best impeller rotation speed was  produced the final surface area of floc which is  0.783 after  of the mixing tank. These types of floc are appropriate for the sedimentation process to be followed by the normal procedure of drinking water treatment.

Keywords

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