In the late 1970s, pinch technology has been developed as a thermodynamic approach to energy savings in industriji.Osnovni tool is called the "Composite Curve" plot, which represented graphically the heat available to heat and requires a process flowsheet. These curves allowed the designer to set realistic goals for minimum heating and cooling utilities required, and establish the existence of a "pinch point" that limits further heat.
Following a systematic design method, based on the avoidance of heat transfer through the pinch, it is possible to design a network of heat exchangers that meet the targets accurately. Over the past 30 years, pinch technology has been applied to thousands of processes in both new and retrofit design. The results were very impressive, with energy savings of 30% or more of exercise. There is renewed interest recently, driven mainly by high oil prices and a desire to reduce carbon dioxide emissions.
Following a systematic design method, based on the avoidance of heat transfer through the pinch, it is possible to design a network of heat exchangers that meet the targets accurately. Over the past 30 years, pinch technology has been applied to thousands of processes in both new and retrofit design. The results were very impressive, with energy savings of 30% or more of exercise. There is renewed interest recently, driven mainly by high oil prices and a desire to reduce carbon dioxide emissions.
...Hydrogen Pinch Technology is a newer program that addressed the problems faced by oil refineries around the 21 century. Until then, the hydrogen availability was not a big problem for most refineries. However, this began to change when more stringent regulations on sulfur content in fuels has led to increased demand for hydrotreating. At the same time, higher aromatics limits meant that the catalytic reforming, traditionally the main source of hydrogen, was ograničen.Neto result is that the existing capacity for hydrogen production often become a bottleneck.
Pinch Technology approach to building a hydrogen Composite curves showing the requirements and sources of on-site hydrogen in terms of purities and stream flow. This diagram allows the engineer to find a "hydrogen pinch" and set targets for the recovery of hydrogen, hydrogen plant production and import requirements. Hydrogen savings experienced are usually hundreds of thousands or even millions, of dollars a year. Alternatively, the liberated hydrogen is used to increase the partial pressures in the individual reactors and to improve their conversion, yield, and selectivity, while increasing the catalyst life.
0 comments: