RETROFITTING REFINERY AND PETROCHEMICAL PLANTS

The author focuses on process improvements as the best way to reduce plant energy use. Despite the progress to date, there is growing evidence that these heat losses can be further reduced economically by about 20-30% in most refineries and petrochemical plants. One way to reduce the losses is to increase recovery of low-level heat by improved heat exchange, which has been the subject of most publications on plant energy conservation. A better way is to develop new process schemes that require less air/water cooling. One useful concept in developing new schemes is to concentrate on heat losses, rather than heat input, as an easier measure of proposed improvements. By an overall heat balance, eliminating a unit of energy loss is equivalent to saving a unit of heat input somewhere in the plant.