Pinch Technology: Energy not only

In late 1970, pinch technology was developed as a thermodynamic approach to energy conservation in industry. The basic tool was called the "Composite Curve" plot, which plots the available heat and the heat required for a process flow diagram. These curves also allows a designer to set realistic goals for minimum heating and cooling required utilities, and identify the existence of "pressure points", which further limits the heat recovery.

Following systematic methods of design, based on preventing the transfer of heat across the pinch, it is possible to design heat exchanger networks that meet the targets accurately. In the past 30 years, pinch technology was applied in thousands of processes, both new and retrofit designs. The results have been impressive, with an energy saving of 30% or more to be achieved. There has been renewed interest recently, mainly driven by high oil prices and the desire to reduce carbon emissions.

In late 1980, researchers at the University of California at Los Angeles pinch apply concepts of mass transfer, triggering a whole new area of ​​research. Instead of drawing compound curves of the temperature and energy, the new approach to map the composition of bulk load. This pioneering work in mass exchange networks was followed by researchers at the University of Manchester, which is applied in water and wastewater minimization. The result of "Water Pinch Technology" was quickly industrial applications worldwide. The results were equally impressive, although the relatively low cost of water in many countries means that the technology has not yet been fully exploited. As water becomes scarcer in the future, we expect that to change.

Hydrogen Technology was a bit more recent application that addresses the problems of the oil refineries around the beginning of the 21st century. Until then, the availability of hydrogen is not an issue for most refineries. However, this began to change when a more stringent legislation on the sulfur content in fuels led to greater demand for hydrotreating. At the same time, new aromatics limits meant that the catalytic reforming, traditionally an important source of hydrogen, was restricted. The net result was that the capacity of existing hydrogen production often become a bottleneck.

The pinch technology approach builds hydrogen compound curves, which shows the demands and sources of hydrogen in the place in terms of flow purities and flow rates. This scheme allows the engineer to find the "hydrogen pinch" and set targets for the recovery of hydrogen, hydrogen production plants and import requirements. Savings experienced hydrogen are typically hundreds of thousands or even millions of dollars per year. On the other hand, the released hydrogen has been used to increase the partial pressures in some reactors and improve conversion and selectivity performance, while increasing the life of the catalyst.