Development of Advanced Recovery-Separation-Degradation Solutions for Green Treatment of Oily Sludge from Petroleum Industry

Oily sludge is a major hazardous waste generated in large volumes from the petroleum industry. Due to its toxic nature, safe disposal of oily sludge becomes challenging and costly. Economic losses can be incurred if the valuable oil is not recycled from the sludge. Previously, various methods were developed to investigate sludge oil recovery, however, mixed results have been obtained and furthermore little attention has been given to the quality of the recovered oil. In terms of the conventional oil sludge disposal approaches, most of them are either inadequate to meeting environmental standards or having various limitations. Besides, large volume of high-content oily wastewater is generated from the sludge disposal and little attention has focused on its effective treatment. Thus, there are growing interests for better oily sludge recovery and treatment solutions. In response to the needs, the proposed research will focus on the advancement and development of novel and green oil recovery and waste disposal technologies. The perspectives of Recovery (of oil), Separation (of wastes), and Degradation (of hydrocarbons) are the main mechanisms for achieving the goals through the following designed tasks: (1) To develop advanced oil recovery approaches with improved oil recovery efficiency and high-purified oil quality through using an integrated techniques of supercritical fluid extraction (SFE) and differential scanning calorimetry (DSC); (2) To discover new microbial strains with high capabilities in producing bio-surfactants and recovering oil from sludge, and their ability in recovering oil will be assessed through an optimized sludge washing process; (3) To explore the biodegradability of residual sludge (i.e., the sludge after its majority of oil being recover by bio-surfactant and SFE techniques) under designed bio-augmentation scenarios for further waste disposal; (4) To develop a submerged PTFE-membrane-bioreactor microfiltration-adsorption unit (PTFE-MABR) through using a new synthetic membrane material and a green process design for handling large volume of high-content oily wastewater generated from the sludge treatment process. A variety of absorbents will be used in conjunction with the MBR unit to remove the impurities in the wastewater effluent. The proposed research will focus on Canada's oily sludge issue and aims to develop green technologies for improving oily sludge management practices in Canada. The research outputs will be informative for sound design of oily sludge treatment in industrial application, and will eventually benefit petroleum industrial stakeholders, Canadian communities and environment. The proposed research will also help train a number of HQPs for enhancing their abilities to address Canada's future environmental challenges.