Bioremediation of oily sludge-contaminated soil by stimulating indigenous microbes

Abstract

In situ bioremediation of oily sludge-contaminated soil by biostimulation of indigenous microbes through adding manure was conducted at the Shengli oilfield in northern China. After bioremediation for 360 days, total petroleum hydrocarbon (TPH) content was reduced by 58.2% in the treated plots compared with only 15.6% in the control plot. Moreover, bioremediation significantly improved the physicochemical properties of the soil in the treated plot. Soil microbial counts and community-level physiological profiling were also examined. Manure addition increased TPH degraders and polycyclic aromatic hydrocarbon (PAH) degraders in the contaminated soil by one to two orders of magnitude. The activity and biodiversity of soil microbial communities also increased markedly in the treated plot compared with that of the control. Finally, biotoxicity was used to evaluate the soils and a sharp increase in the EC50 of the soil after bioremediation was observed, indicating that bioremediation had reduced the toxicity of the soil.

Treatment of phenanthrene and benzene using microbial fuel cells operated continuously for possible in situ and ex situ applications

“…Toxicity levels of the treated wastewater must be below a permissible levels and pose no risk to public health and the environment (Liu et al, 2010;Melo et al, 2013). Fig.…”

Comparative analysis of microbial communities during enrichment and isolation of DDT-degrading bacteria by culture-dependent and -independent methods

“…Investigations have demonstrated that bioremediation is a feasible solution for treating organic contaminants including PCB, PCNB, DDT, DDE and DDD (Fang et al, 2010;Li and Yang, 2013;Liu et al, 2010;Wang et al, 2016a). High efficiency degradation strains are a key factor for bioremediation of organic pollutants.…”

Biological degradation of oil sludge: A review of the current state of development

“…In recent years, most refineries treat oil sludge using conventional methods which includes; physical treatment (storage, landfilling, combustion and incineration in a rotary kiln, lime stabilization, stabilization and solidification) (Wright and Noordhius, 1991;Karamalidis and Voudrias, 2001;Bhattacharyy and Shekdar, 2003;Radetski et al, 2006;Beech et al, 2009;Liu et al, 2010), chemical treatment (oxidative thermal treatment, treatment with fly-ash, pyrolysis treatment and solvent extraction) (Bonnier et al, 1980;Atlas, 1984;Taiwo and Otolorin, 2009) and biological treatment (landfarming, bio-reactor treatment and composting) (Pereira-Neta, 1987;Piotrowski, 1991;Lees, 1996;Singh et al, 2001;Hejazi et al, 2003;Mahmoud, 2004;De-qing et al, 2007;Srinivasarao et al, 2011;Udotong et al, 2011;Besalatpour et al, 2011). Most of the physical and chemical methods require expensive equipments and high energy to treat the oil sludge.…”

“…Some of these methods convert oil sludge into lighter products and reduce the quantity before disposal. Some of the methods may generate by-products that may need to be treated using other methods before disposal to a landfill (Liu et al, 2010), making them more expensive. Exam-ples of the conventional methods used are discussed below.…”

“…Oil sludge has been classified by the United States Environmental Protection Agency (US EPA) as a hazardous organic complex (US EPA, 1997; Liu et al, 2010). This contaminant enters the environment as a result of human activities, which includes deliberate dumping, improper treatments and management, storage, transportation and landfill disposal.…”