Energy and Resource Utilization of Refining Industry Oil Sludge by Microwave Treatment

Abstract

The oily sludge from crude oil contains hazardous BTEX (benzene, toluene, ethylbenzene, xylene) found in the bottom sediment of the crude oil tank in the petroleum refining plant. This study uses microwave treatment of the oily sludge to remove BTEX by utilizing the heat energy generated by the microwave. The results show that when the oily sludge sample was treated for 60 s under microwave power from 200 to 300 W, the electric field energy absorbed by the sample increased from 0.17 to 0.31 V/m and the temperature at the center of the sludge sample increased from 66.5 °C to 96.5 °C. In addition, when the oily sludge was treated for 900 s under microwave power 300 W, the removal rates were 98.5% for benzene, 62.8% for toluene, 51.6% for ethylbenzene, and 29.9% for xylene. Meanwhile, the highest recovery rates of light volatile hydrocarbons in sludge reached 71.9% for C3, 71.3% for C4, 71.0% for C5, and 78.2% for C6.

Analysis of the Changes in the Components of the Chemical Hot Washing Treatment of Oily Sludge and the Mechanism of Oil Removal

“…3−5 Oily sludge is difficult to treat due to its natural emulsifiers such as resins and asphaltenes as well as artificially added surfactants, making it heavily emulsified, highly viscous, high in oil content, rich in fine particles, and difficult to dewater. 6 Several technologies exist that can recover crude oil from oily sludge and render it harmless, including solvent extraction, 7 pyrolysis, 8 electrolysis, 9 microwave, 10 and chemical thermal washing. 11 However, oily sludge contains a large amount of economically valuable oil resources, and HJ 607-2011 stipulates that oily sludge and oil silt with an oil content greater than 5% should be recycled, meaning that oil resources need to be recovered.…”

Mechanism of Magnetic Nanoparticle Enhanced Microwave Pyrolysis for Oily Sludge

“…For nonpolar substances with molecular structures, the effect is poor even though they do not directly heat. Through experiments, researchers found that adding microwave absorbers such as SiC, Fe 2 O 3 , graphite, activated carbon and pyrolytic coke powder to the heating material can make the pyrolysis effect more significant [14][15][16]. Salema et al [17] found that the addition of biochar as a material with good dielectric properties to oily sludge could significantly improve the heating rate of microwave pyrolysis and promote the decomposition of hydrocarbon substances in oily sludge.…”

“…In recent years, nanotechnology has advanced by leaps and bounds. A new type of nanomaterial, magnetic nanoparticles, has attracted increasing attention from scientific and technological workers around the world [15]. Mario et al [29] believe that the adsorption performance of magnetic nanoparticles depends largely on its particle size.…”

An Overview of the Current State and Prospects for Oil Recovery from Oily Sludge

“…As a result, refineries generate more oil sludge, which collects at the bottom of tanks when oil is being stored. This sludge negatively affects the tank's capacity and operational safety [1][2][3][4][5]. When discussing the production, exploration, storage, transportation, and processing of crude oil, the term "oil sludge" refers to a thick, viscous, and challenging-to-handle fluid [6][7][8][9][10].…”