Hydrogen pinch applications in chemical industries

Hydrogen is the fuel of the future and it is the most important renewable energy source. It offers solutions to some of the greatest energy problems and challenges facing future generations. Hydrogen is a well-established industrial gas that nowadays has many applications. At the same times, it reacts with many elements and for that reason is used in many industries. It is investigated that to increase the yield through the more efficient used of hydrogen on the plant, to achieve lower cost alternatives, to reduce CO2 emission, etc. In addition to these, there are main critical problems based on hydrogen utilization in chemical plant. Operating cost increases if more hydrogen needs to be produced or purchased. If hydrogen production capacity needs to be scaled up, capital investment cost also increases. To eliminate the critical problems hydrogen management is necessary especially for petrochemical refineries and some other chemical industries. Hydrogen pinch as a concept is an optimization of hydrogen supply and demand. Utilities are analyzed in terms of quantity and quality to identify the most appropriate internal recovery opportunities. Hydrogen management become a priority in the current refinery operations and when planning to produce the lower sulphur gasoline and diesel fuel. The effective management and efficient integration of hydrogen and off gases are becoming important tasks for all refineries. Increased demand for the lighter fuels and products, a desire for higher performance products, and an insistence on the more environmentally acceptable products require the hydrogen management around the plants. In this study, the hydrogen pinch analysis is to perform a mass balance on hydrogen sources and demands in the petrochemical industry hydrogen network. By this way, surplus hydrogen amount of network is determined by using graphical method, minimum hydrogen demand for the refinery is identified, strategies are developed to achieve minimum demand, and yield is improved on key process units, capital cost reduces and ongoing operating cost savings.Energy optimization is provided by hydrogen pinch approach. As a result, hydrogen recovery is obtained approximately %30. In addition to these results, operating cost is decreased according to the unit operating costs and annual cost of hydrogen as a raw material. In this study, refinery hydrogen network which is selected to management needs pure hydrogen amount 277.2mol/s to operate exactly. By applying hydrogen pinch approach pure hydrogen amount of network decreased to 268.8mol/s. Additionally, purification process has applied and pure hydrogen amount of network decreased to 196.8mol/s. Exergy analysis has applied to the available and retrofit system to examine the exergy efficiency and integrated system relation. Excess hydrogen amount has decreased by purification of outlet hydrogen and recycled to the system. As a result, fresh hydrogen consumption has decreased. For six units, exergy efficiencies have calculated and compared available system. Retrofit system exergy efficiency is higher than available system. This means that retrofitted system has useful energy and more ecofriendly.