Characterization of oily sludge from a Tehran oil refinery

Abstract

In this study, oily sludge samples generated from a Tehran oil refinery (Pond I) were evaluated for their contamination levels and to propose an adequate remediation technique for the wastes. A simple, random, sampling method was used to collect the samples. The samples were analyzed to measure Total petroleum hydrocarbon (TPH), polyaromatic hydrocarbon (PAH) and heavy metal concentrations in the sludge. Statistical analysis showed that seven samples were adequate to assess the sludge with respect to TPH analyses. The mean concentration of TPHs in the samples was 265,600 mg kg⁻¹. A composite sample prepared from a mix of the seven samples was used to determine the sludge's additional characteristics. Composite sample analysis showed that there were no detectable amounts of PAHs in the sludge. In addition, mean concentrations of the selected heavy metals Ni, Pb, Cd and Zn were 2700, 850, 100, 6100 mg kg⁻¹, respectively. To assess the sludge contamination level, the results from the analysis above were compared with soil clean-up levels. Due to a lack of national standards for soil clean-up levels in Iran, sludge pollutant concentrations were compared with standards set in developed countries. According to these standards, the sludge was highly polluted with petroleum hydrocarbons. The results indicated that incineration, biological treatment and solidification/stabilization treatments would be the most appropriate methods for treatment of the sludges. In the case of solidification/stabilization, due to the high organic content of the sludge, it is recommended to use organophilic clays prior to treatment of the wastes.

Isolation and characterisation of crude oil sludge degrading bacteria

“…This has resulted in an increased generation of large amounts of oily waste (Bhattacharyya and Shekdar 2003). An important example of such waste is crude oil sludge, which is a highly viscous material consisting of a mixture of oil contaminated sand (clay, silica and oxides) and the associated chemicals and water used during the refining process (Heidarzadeh et al 2010). Crude oil sludge is mainly generated during the cleaning of storage tanks and the treatment of waste water from refineries.…”

Bioremediation of Petroleum Sludge Impacted Soils Using Agro-Waste from Moringa Seed

“…Thereafter, in subsequent experiments, they were watered regularly to retain 60-70% moisture to make sure the moisture content was not below the recommended range for microorganisms. Also, the contents of the experiment were manually mixed twice a week to allow aeration and homogenous mixture of the materials [45,46]. At 30 days interval, samples were collected and air-dried for two weeks at ambient temperature, rolled manually with a steel roller, sieved to remove stones and debris.…”

Soil Washing for Reduction of Aromatic and Aliphatic Contaminants in Soil

“…Iran is seriously facing soil contamination problem, due to owning 8.58% of the global oil fields; generating 35 million tons of petrochemical products; and having more than 20 000 km of pipelines . The extraction of 1 kg of crude oil usually generates 10–20 g of waste residues . As can be seen in Fig.…”