Formulation of Bio-Based Washing Agent and Its Application for Removal of Petroleum Hydrocarbons From Drill Cuttings Before Bioremediation

Abstract

Drill cuttings from petroleum exploration and production sites can cause diverse environmental problems. Total petroleum hydrocarbons (TPHs) are a major pollutant from the use of polyolefin-based mud. As an alternative to incineration, this study investigated the application of surfactant-enhanced washing technology prior to bioremediation. The washing step was necessary because the initial TPH concentrations were quite high at approximately 15% (w/w). Washing agents were formulated by varying the concentration of lipopeptide biosurfactant (in foamate or cell-free broth), Dehydol LS7TH (fatty alcohol ethoxylate 7EO, oleochemical surfactant) and butanol (as a lipophilic linker) at different salinities. The most efficient formula produced a Winsor Type I microemulsion (oil-in-water microemulsion) with polyolefin and contained only 20% (v/v) foamate and 2% (v/v) Dehydol LS7TH in water. Due to the synergistic behavior between the anionic lipopeptides and non-ionic Dehydol LS7TH, the formula efficiently removed 92% of the TPHs from the drill cuttings when applied in a jar test. To reduce the cost, the concentrations of each surfactant should be reduced; thus, the formula was optimized by the simplex lattice mixture design. In addition, cell-free broth, at a pH of 10, containing 3.0 g/L lipopeptides was applied instead of foamate because it was easy to prepare. The optimized formula removed 81.2% of the TPHs and contained 72.0% cell-free broth and 1.4% Dehydol LS7TH in water. A 20-kg soil washing system was later tested where the petroleum removal efficiency decreased to 70.7% due to polyolefin redeposition during separation of the washing solution. The remaining TPHs (4.5%) in the washed drilled cuttings were further degraded by a mixture of Marinobacter

Application of Hydrophilic–Lipophilic Deviation Equations to the Formulation of a Mixed‐Surfactant Washing Agent for Crude Rice Bran Oil Removal from Spent Bleaching Earth

“…Buathip (2018) reported that the CMC of LS3 obtained from the adsorption on the VBE‐solid surface at a solution pH of 7.0 ± 0.5 at room temperature was approximately 3 vol.%. These results are consistent with those of Arpornpong et al (2020), who found that the greater total petroleum hydrocarbon removal was observed as the biosurfactant concentration increased beyond its CMC value.…”

“…In contrast, negative HLD values (HLD < 0) are obtained for hydrophilic surfactants that produce a Winsor type I microemulsion. For soil washing applications, the washing solution is formulated at HLD = 0 because a Winsor type III microemulsion gives the lowest interfacial tension (IFT) between the washing solution and the oil, resulting in high oil removal efficiency (Arpornpong et al, 2018, 2020; Naksuk et al, 2009; Tongcumpou et al, 2003).…”

“…An ideal washing solution for soil washing is biodegradable and has high pollutant solubilization ability and low sorption by soil particles (Befkadu and Chen, 2018). Using anionic‐nonionic mixed surfactants for solubility enhancement and desorption of contaminants from the soil is more efficient than using a single surfactant (Arpornpong et al, 2020; Paria and Khilar, 2004). In numerous scientific studies, mixed‐surfactant systems have been used to enhance the desorption of contaminants from various adsorbents; examples include enhancement of the desorption of hexachlorobenzene from kaolin (Yuan et al, 2007), enhancement of the solubilization of herbicides (Galan‐Jimenez et al, 2015), and enhancement of the solubilization of DNAPL from aquifers (Zhao et al, 2006).…”

Research Progress and Prospects on the Treating and Disposal for Waste Oil-Based Drilling Cuttings from Shale Gas Wells

“…The experimental results indicated that the oil phase recovery rate was more than 85%, and the total petroleum hydrocarbon content (TPH) of waste residues was less than 2% after the cleaning. In addition, some scholars used biobased surface cleaning agents instead of chemical cleaning agents to remove hydrocarbons in drilling cuttings before microbiological treatment, and the content of hydrocarbons in biologically treated drilling cuttings decreased to less than 1% [54,55]. Compared with single biodegradation or chemical cleaning, the combination of chemical cleaning and biodegradation is more efficient for treating OBDC.…”

Physicochemical Upgrading of a Biodetergent for Application in the Industrial Energy Sector

“…Helmy et al [16] successfully applied a rhamnolipid biosurfactant in the formulation of a washing biodetergent, whose stain removal efficiency was close to that of a standard detergent, thus showing potential as a promising substitute for synthetic surfactants. Arpornpong et al [17] prepared cleaning agents at variable salinity values by changing the concentrations of a lipopeptidic biosurfactant, the natural surfactant Dehydol LS7TH (D) and butanol as a hydrophobic binder. The best formulation led to an oil-in-water (O/W) microemulsion with polyolefin containing no more than 20% (v/v) foam and 2% (v/v) D. Thanks to the synergism of anionic lipopeptides with nonionic D, the preparation was able to remove, in a jar test, > 90% of total petroleum hydrocarbons adsorbed on drill cuttings and fragments.…”