Petroleum refinery liquid wastes: environmental, energy & economic impacts

Analysis of the operation of a petroleum refinery in terms of environmental, energy and economic terms has led to the development of mathematical models which simulate liquid waste generation and treatment. One model is based on a module concept whereby a refinery system is broken down into its smallest elements contributing to the liquid waste generated by the total system. In this way it was possible to account for the many variables associated with petroleum refining and liquid waste generation such as (1) variation in cru.de oils used, (2) sulfur levels. (3) process configurations, (4) product slate, (5) raw water used, and other significant parameters. Liquid wastes are characterized as to (1) sewer segregation, (2) quantity, (3) analysis in terms of the most common parameters and (4) various manners of refinery operations. The data from this liquid waste generation model has been applied to develop a characteristic factor similiar to Nelson's Complexity, for descriping refinery configurations in terms of liquid waste generation from the various processing components of the refinery. A second model has been developed which simulates treatment of the liquid wastes generated by the refinery model. This model considers treatment to produce acceptable effluents suitable for discharge to the environment. Costs associated with the waste treatment system are generated from this model. The combination of the two simulation models permits one to predict the economics of water reuse and recycle, and an example is given showing the application of water reuse to refinery operations in terms of economic incentives. The manner of developing the models permits easy updating and provides a great deal of flexibility which makes it possible to apply the models to many other chemical processing operations aside from petroleum refining. New data can be easily incorporated into the model thereby making it a valuable tool for future study in the general area of chemical processing and liquid waste generation.