TITLE:
Retrofit of the Heat Recovery System of a Petroleum Refinery Using Pinch Analysis
AUTHORS:
John M. Joe, Ademola M. Rabiu
KEYWORDS:
Plant Retrofit; Heat Integration; Crude Distillation Unit; Heat Exchanger Network; Pinch Analysis; Optimization; Remaining Problem Analysis
JOURNAL NAME:
Journal of Power and Energy Engineering,
Vol.1 No.5,
November
26,
2013
ABSTRACT: Energy
efficiency has become an important feature in the design of process plants with
the rising cost of energy and the more stringent environmental regulations
being implemented worldwide. In South
Africa, as elsewhere, most process plants
built during the era of cheap energy place little emphasis on the need for
energy recovery due to the abundance of cheap utilities sources such as coal.
In most of these plants, there exist significant potential for substantial
process heat recovery by conceptual design of the heat recovery system. By
maximizing heat recovery from the processes, there will be a reduction in the
process utilities requirement and the associated environmental effects. Pinch
analysis has been demonstrated to be a simple but very effective tool for heat
integration and optimization of chemical plants. This study uses the pinch principle to retrofit the
heat exchanger networks (HEN) of the crude distillation unit of an integrated petroleum
refinery to evolve a HEN that features optimum energy recovery. The network was
further relaxed by trading off energy cost with capital cost to obtain an
optimal HEN topology not too different from the existing network. The
simulation works were implemented in AspenPlus v8.0 environment. Analysis
revealed that 34 per cent saving on energy usage per annum is realizable. This
significant saving in energy also results in diminished gaseous pollutants
associated with energy usage.