Treatment of petroleum refinery wastewater containing heavily polluting substances in an aerobic submerged fixed-bed reactor

Abstract

Petroleum refineries produce large amount of wastewaters, which often contain a wide range of different compounds. Some of these constituents may be recalcitrant and therefore difficult to be treated biologically. This study evaluated the capability of an aerobic submerged fixed-bed reactor (ASFBR) containing a corrugated PVC support material for biofilm attachment to treat a complex and high-strength organic wastewater coming from a petroleum refinery. The reactor operation was divided into five experimental runs which lasted more than 250 days. During the reactor operation, the applied volumetric organic load was varied within the range of 0.5-2.4 kgCOD.m(-3).d(-1). Despite the inherent fluctuations on the characteristics of the complex wastewater and the slight decrease in the reactor performance when the influent organic load was increased, the ASFBR showed good stability and allowed to reach chemical oxygen demand, dissolved organic carbon and total suspended solids removals up to 91%, 90% and 92%, respectively. Appreciable ammonium removal was obtained (around 90%). Some challenging aspects of reactor operation such as biofilm quantification and important biofilm constituents (e.g. polysaccharides (PS) and proteins (PT)) were also addressed in this work. Average PS/volatile attached solids (VAS) and PT/VAS ratios were around 6% and 50%, respectively. The support material promoted biofilm attachment without appreciable loss of solids and allowed long-term operation without clogging. Microscopic observations of the microbial community revealed great diversity of higher organisms, such as protozoa and rotifers, suggesting that toxic compounds found in the wastewater were possibly removed in the biofilm.

Performance of advanced oxidation processes to treat the petroleum wastewater A review

“…Table 1. Characteristics of petroleum wastewater and standard discharge limits for refinery effluents reported by various researchers (Vendramel et al, 2015) 8 When a crude oil contained appreciable quantities of Sulphur, it was called sour crude. Thus, Sour water was a specific stream of petroleum refineries, which contain slowly biodegradable compounds and toxic substances (Coelho et al, 2006).…”

“…In addition, the oil wells produce the petroleum wastewater during oil drilling, which often contain recalcitrant compounds and rich in organic pollutants. Therefore, the petroleum wastewater could not be treated easily and difficult to be treated biologically (Rasheed et al, 2011;Vendramel et al, 2015). Removal of pollutants from the petroleum wastewater is a requirement for reuse of water and obtained to environmental standards (Farajnezhad & Gharbani, 2012).…”

“…Thus, petroleum refineries produced large volumes of wastewater including oil well produced water brought to the surface during oil drilling, which often contain a recalcitrant compounds and rich in organic pollutants therefore could not be treated easily and difficult to be treated biologically (Vendramel S. et al, 2015;Rasheed et al, 2011;Asatekin A. et al, 2009). Removal of pollutants produced by industrial plants was the requirement for reuse of water and obtained to environmental standards (Farajnezhad and Gharbani, 2012).…”

Effects of Abiotic Factors on Microbial Characteristics of Petroleum Contaminated Soils in Northern China

“…ETROlEUM is a complex compound containing a mixture of saturated and unsaturated alkanes, polyaromatic hydrocarbons (Pahs) and, in minor amounts, inorganic compounds like sulfides and nitrates [1][2][3][4][5].…”

Assessment and optimization of environmental systems using data analysis and simulation.

“…Generally, it is challenging to remove small suspended oil particles and dissolved elements by sole use of physical or chemical technologies. In this case, the processes that rely on the ability of microorganisms to use wastewater components for their metabolisms are found to be more cost-effective and sustainable compared to physical and chemical oxidation processes (Vendramel et al 2015).…”