Impact of salinity on coagulation and dissolved air flotation treatment for oil and gas produced water

2013 ◽  
Vol 49 (2) ◽  
pp. 135-143 ◽  
Author(s):  
Jessica M. Younker ◽  
Margaret E. Walsh

Produced water is a major wastewater stream in the oil and gas industry which typically consists of dispersed and dissolved oils, and high levels of salinity. Despite concerns that dissolved aromatics in produced water may be detrimental to marine life, discharge regulations and treatment technologies for produced water largely focus on dispersed oil and grease removal. The purpose of this research project was to investigate coagulation with ferric chloride (FeCl3) and dissolved air flotation (DAF) at bench-scale for the removal of both dispersed and dissolved oils from synthetic and offshore produced water samples, with a specific focus on the impact of salinity on the coagulation process. Coagulation and DAF treatment of the produced water samples achieved high removals of dispersed oil and grease, but had limited impact on dissolved aromatics. The coagulation process in the saline produced water samples reduced dispersed oil and grease concentrations from 100 mg/L to below North American discharge limits (i.e. 30 mg/L in Canada, 29 mg/L in the USA) under all conditions tested, while the effectiveness of coagulation treatment in the fresh water synthetic samples was highly dependent on coagulation pH.

1995 ◽  
Vol 31 (3-4) ◽  
pp. 1-23 ◽  
Author(s):  
James K. Edzwald

Principles of dissolved air flotation (DAF) discussed include: bubble formation and size, bubble-particle interactions, measures of supplied air, and modeling of the reaction and clarification zones of the flotation tank. Favorable flotation conditions for bubble attachment or adhesion to particles requires a reduction in the charge of particles and production of hydrophobic particles or hydrophobic spots on particle surfaces. A conceptual model for the bubble-particle reaction zone based on the single collector collision efficiency is summarized and discussed. An alternative modeling approach is considered. Clarification or separation zone modeling is based on particle-bubble agglomerate rise velocities. The application of DAF in drinking water treatment is addressed beginning with summaries of design and operating parameters for several countries. DAF should not be considered as a separate process, but integrated into the design and operation of the overall treatment plant. This concept shows that flocculation ahead of DAF has different requirements regarding floc size and strength compared to sedimentation. The efficiency of DAF in removing particles and reducing particle loads to filters needs to be integrated into DAF plant design. The impact on filtration performance is illustrated. Finally, fundamental and applied research needs are addressed.


JUMINTEN ◽  
2020 ◽  
Vol 1 (2) ◽  
pp. 93-104
Author(s):  
Amanullah Fathurrahman ◽  
Iriani Iriani ◽  
Dwi Sukma Donoriyanto

CV. ABC merupakan pabrik yang bergerak dalam bidang olahan kayu seperti speaker aktif dan mebel-mebel. Dimana perusahaan tersebut memiliki sebuah komitmen internal dalam proses produksinya, agar dapat mengurangi dampak lingkungan dan memelihara ekosistem disekitarnya. Namun dalam kenyataannya, dalam proses produksinya baku mutu air perusahaan melebihi dari standar PERGUBJATIM No. 72 Tahun 2013, COD (Chemical Oxygen Demand) yang diatas batas standar sebesar 61,40 mg/l dan Oil and Grease sebesar 12 mg/l. Dimana akan berdampak pada lingkungan sekitar yang dapat mengganggu kesehatan lingkungan sekitar, selain itu dapat berdampak menurunnya produktivitas dan kinerja lingkungan perusahaan. Dengan adanya permasalahan tersebut pendekatan yang tepat untuk membantu perusahaan agar dapat mampu meningkatkan produktivitas serta kinerja lingkungan tersebut adalah dengan menerapkan metode Green Productivity (GP). Penelitian ini bertujuan untuk dapat mengevaluasi pengelolaan limbah berbasis Green Productivity, serta dapat memberikan usulan perbaikan dalam pengelolaan limbah. Hasil yang didapat diketahui bahwa terdapat 2 alternatif yang dapat menurunkan tingkat BOD (Biological Oxygen Demand), COD (Chemical Oxygen Demand), TSS (Total Suspeded Solid), Oil and Grease. Akan tetapi solusi yang dapat dijadikan usulan perbaikan adalah alternatif 2, yitu pemasangan alat DAF (Dissolved Air Flotation). Keuntungan yang didapatkan CV. ABC dengan alternatif 2 ini adalah peningkatan Green Productivity Index yang ditunjukan Green Productivity Ratio sebesar 13,06 dan Tingkat Produktivitas meningkat sebesar 0,01 %


Author(s):  
Siyasanga Mbulawa ◽  
Seteno Karabo Obed Ntwampe ◽  
Moses Basitere ◽  
Yolanda Mpentshu ◽  
Cynthia Dlangamandla ◽  
...  

Delipidation is a method of defatting that is generally associated with the removal of residual lipids or lipid groups from matrices in which they are present in minute quantities. The bio-delipidation of protein-rich poultry slaughterhouse wastewater (PSW) pre-treated with a dissolved air flotation (DAF) system was developed using microbial lipases from bacterial strains isolated from the PSW. The efficacy of the bio-delipidation system was quantitatively characterised by comparing the quality parameters i.e., fats, oil and grease (FOGs), turbidity, total suspended solutes (TSS), total chemical oxygen demand (tCOD) and protein concentration of the DAF pre-treated PSW and bio-lipidized samples. As hypothesised, the bio-delipidation system was able to effectively reduce the levels of these quality parameters when crude lipases of Bacillus cereus AB1 (BF3) and Bacillus cereus CC-1 (B30) strains were used. Strain-dependent quality characteristics were also observed in bio-delipidized samples. The study successfully managed to complement physical reduction techniques (DAF) with biological strategies (bio-delipidation) for improved PSW quality, with potential industrial applications.


1994 ◽  
Vol 29 (8) ◽  
pp. 47-50 ◽  
Author(s):  
Kee Kean Chin

Processes used in the treatment of a petroleum refinery wastewater included initial API oil separator to be followed by dissolved air flotation and an extended aeration system. The API oil separator removed most of the settleable solids and oil. The residual oil varied from around 680 mg/l to 104 mg/l and was further treated with chemical coagulation, flocculation and dissolved air flotation which remove more than 80 % of the oil and grease. Mean COD after dissolved air flotation was around 970 mg/l and it was lowered to around 378 mg/l using the extended aeration biological system at 15-day HRT. The final effluent COD/BOD ratio was high indicating the presence of a high percentage of refractory organic compounds.


2013 ◽  
Vol 40 (12) ◽  
pp. 1164-1172 ◽  
Author(s):  
Wayne Chung ◽  
Stephanie Young

Restaurant dishwashers consume a large quantity of fresh water and produce significant amounts of high strength oily wastewater which may cause serious problems when discharged into the sewer. An analysis of restaurant dishwasher effluent (RDE) from a busy upscale restaurant identified high levels of oil and grease, chemical oxygen demand (COD), biochemical oxygen demand (BOD), alkalinity, pH, and chlorine, but low levels of nitrogen and phosphorus. In this study, RDE was treated using an internationally patented chemical dissolved air flotation (chemical DAF) system. The chemical DAF system was designed so that coagulation, flocculation, and flotation processes could be carried out within the same reactor. The treatment system is therefore small and compact and suitable for use in restaurants where space is limited. The treatment performance of the chemical DAF was evaluated by determining optimal process conditions, contaminant removal efficiencies, and residual contaminant concentrations. It was found that removal efficiencies of 98.90%, 93.16%, 98.68%, 90.04%, and 88.20% could be achieved under optimal process conditions for turbidity, oil, TSS, BOD5, and COD, respectively. Total coliform and E. coli were not detected in either the raw dishwasher effluent or the treated dishwasher effluent due to the use of sodium hypochlorite as a dishwashing sanitizer. Water quality of the treated effluent met the criteria put forth in the Canadian Guidelines for Domestic Reclaimed Water for Use in Toilet and Urinal Flushing, with the exception of BOD5. Present findings suggest that chemical DAF is a promising treatment process for the removal of contaminants from restaurant dishwasher effluent.


Sign in / Sign up

Export Citation Format

Share Document