Ecology, Environment and Conservation Paper

TREATMENT OF OIL CONTENT IN OILFIELD PRODUCED WATER USING CHEMICALLY MODIFIED WASTE SAWDUST AS BIOSORBENT

Adil H. Rashid, Ali A.Hassan, Raid T. Hadi and Ahmed Samir Naje 1Al- Muthanna University, Chemical Engineering Departmen, Al- Muthanna, Iraq.

Abstract

Produced water is one of the major technical, environmental, and economical problems associated with oil and gas production. Due to legislation and environmental concerns, it was very important to treat the produced water before recycling and reusing. The removal of hazardous contaminants present in many of these industrial streams became the main interest of many researchers and different methods and techniques such as gravity separation, membrane -filtration, ultra-filtration, biological processes, etc. were developed in this field. The present study showed that the waste sawdust (WS) is an effective adsorbent for the removal of organic compounds from produced water aqueous solution. The raw waste sawdust (WS) was analyzed using Fourier Transform Infra-Red (FTIR) for identification of functional groups present on the adsorbent surface. Adsorption experiments were carried out in batch mode for the removal of the residuals organic pollutants present in the produced water. The effects of different parameters such as pH, adsorbent dosage, particle size and contact time on the adsorption uptake at room temperature were investigated. The highest percentage removal of organics was found to be 85.5% at 2 g of adsorbent dosage, pH = 3, 90 min, and 0.075 mm particle size at room temperature. At the same conditions, 96.4% of organics was adsorbed by treated waste sawdust. Furthermore, the high adsorption capacity of modified waste sawdust to remove organics from aqueous solution makes it preferable and attractive alternative to commercial adsorbent. The adsorption data for waste sawdust and treated waste sawdust was fitted into Langmuir and Freundlich isotherm equations. It appears that the Freundlich model best fits the experimental results over the experimental range with good coefficients of correlation (R2>0.95). Finally, treated waste sawdust is characterized significantly by its high ability to adsorb oil and suspended solids from produced water, as a result, reduces the economic cost of water treatment.