Study of refining wastewater pollution: Case of vegetable oil refining industry Morocco

Rapid industrial development and growth of cities throughout the world especially in developing nations have led to the recognition and an increase in understanding of the relationship between pollution, public health and the environment at large. Generally, industries produce more pollutants than any other sector in society. Previously, effluents from the vegetable oil industry were directly discharged into the soil or ground water. However, due to their important environmental impact, national legislations have become stricter and imposed stringent norms. The oleaginous industry produces large volumes of aqueous wastes that must be first characterized as a step to their management. This study is focused on the sources, characteristics, and composition of vegetable oil refinery wastewaters. The obtained results were very much useful in identification and rectification of operational and maintenance problems as well as the future expansion to be carried out in the plant to meet the increased hydraulic and organic loadings. Types of wastewaters evaluated are refinery, soap, acidic and process wastewater. Samples were collected and analysed for the following water quality parameters: biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS) and oil & grease phenol and surfactant. Results present data for 13 week sampling period. In our characterization studies, the maximum values COD were 205800 mgL-1 and 240500 mgL-1 for acidic and soap wastewater respectively. These results confirm that the vegetable oil refinery wastewater has a high organic pollution load. Knowledge of the effluent quality parameters and subsequently the treatability of wastewater would help for the development of sustainable treatment strategies