معالجة واعادة استخدام المياه الناتجة من حقول نفط الاحدب العراقية == Treatment And Reuse of Produced Water From Al - Ahdab Iraqi Oilfields
Author name:
حسين باسم عليوي
Supervisor name:
Basma A. Abdul | Majeed
General topic:
Chemical Engineering
Specific topic:
Chemical Engineering
Degree:
Doctorate
University:
University of Baghdad - College Of Engineering - Department Of Chemical Engineering
Language:
English
University location:
Baghdad
First pages:
38T281 - p.pdf
Abstract:
الهدف الاساسي من هذا البحث هو تطوير طريقة عملية لمعالجة المياه المنتجة من حقول النفط العراقية. في هذه الدراسة تم توظيف نظام متحد من ثلاث عمليات معالجة هي التخثير والامتزاز والتبادل الايوني لازالة وتقليل بعض الملوثات الرئيسية مثل العكورة والمحتوى الزيتي وم | The overall goal of this research was to develop a practical method of treating co - produced waters from oil - field sources. In this study, combined coagulation - adsorption - ion exchange treatment was employed for the removal of some main contaminants like turbidity, oil content, and total dissolved solids from produced water. These combination steps are not studied before. The wastewater used in this work was taken freshly form Al - Ahdab oilfields. The coagulants used in this study were aluminum sulfate (alum) as a primary coagulant and calcium hydroxide (lime) as a coagulant aid. The performance of these coagulants was investigated through jar test by comparing turbidity removal at different coagulant / coagulants aid ratio, coagulant dose, water pH, and sedimentation time. The best conditions for turbidity removal can be obtained at coagulant dosage of 80 mg/L at pH 6 and 120 min for sedimentation time. There was an improvement in the turbidity removal when 25% lime was used in conjunction with 75% alum. At these conditions, the turbidity reading was reduced from 92 to 2.1 NTU. In addition, an attempt was made to examine the relationship between turbidity (NTU) and total suspended solids (mg/L) on the same samples of produced water. This study presents an investigation on the technical feasibility of using organoclay for adsorption of oil content from produced water. The organoclay was prepared by combination of Iraqi bentonite with quaternary amine (tetraethylammonium chloride). Batch mode experiments were conducted to study the effects of amine/ bentonite ratio, organoclay quantity, pH, and contact time. The analysis results showed that the organoclay adsorbent was very effective in removing oil content from produced water and the best results obtained for the removal of oil content are 16 g/L of prepared organoclay having 35 g amine/ 100 g bentonite, pH 3, and 120 min for contact time. These results reduce the concentration of oil content from 532.1 to 2.7 mg/L. Equilibrium adsorption isotherms and kinetics were investigated. The adsorption isotherm data were fitted well to Temkin isotherm as highest coefficient of correlation (R2=0.996) and lowest value of standard deviation (Sd=2.385). The adsorption kinetic data were fitted very well the pseudo - second order kinetics model (R2=0.997 and Sd=1.644). The continuous experiments were carried out in a fixed - bed column. The results revealed that adsorption capacity increases with increasing bed depth and with decreasing flow rate. In this work, a continuous ion exchange study in fixed - bed columns was performed to reduce TDS concentration from produced water. The experiments were subjected to lab - scale ion exchangers, consisting of two types of commercial resins connected in series. The two types of resins used in this work were : strongly acidic cation exchanger of type Dowex 650C and strongly basic anion exchanger of type Dowex I. 550A. Comparison of Thomas, Yoon - Nelson, and Adams - Bohart models with experimental kinetics results was done, and model parameters were evaluated by linear regression analysis for TDS reduction in different bed depths and flow rates. The obtained experimental data were in good agreement with Thomas and Yoon - Nelson models (R2 reaches to 0.996). Reverse flow regeneration was carried out in a fixed - bed column for exhausted resin by washing with diluted acid and base solutions. The regenerated resin was reused in the same column. Approximately, 65% of the original sorption capacity was restored.
