Use of the steam at 1.4 bar in the MDI plant to heat caustic soda 30%

Identifier:  TFG:9138

Handle: https://hdl.handle.net/20.500.11797/TFG9138

Authors:  Zheng, Siyi

Abstract:
The project is based on the energy use of the supersaturated low-pressure steam left over from the MDI/MDA plant, which is currently being expanded into the atmosphere. The energy saving strategy consists of two stages, the first is based on the configuration of a steam delivery pipe from the MDI plant to the ELO plant, the second stage consists of the configuration of two heat exchangers to heat the caustic soda up to 120ºC. In the first stage of the project, the pipe will be designed taking into account the pressure losses, condensation, as well as the quality and quantity of steam in order to ensure that it reaches the appropriate conditions at the entrance to the first heat exchanger. The design of the first heat exchanger will be designed to be capable of heating the caustic soda at 30% concentration from 79ºC to a temperature of 100ºC, likewise the second heat exchanger will achieve that the caustic soda reaches a temperature of 120ºC. The initial configuration of the heat exchangers will be carried out with the Aspen HYSYS software, then it will be compared with the exchangers of the company J. Negre. Likewise, safety, environmental and maintenance studies are contemplated. The CO2 foodprint will be calculated in order to verify that emissions into the atmosphere are reduced. Regarding the safety of the process, a HAZOP study will be carried out and emergency plans will be defined. For the maintenance of the process, the inspection times of the equipment and pipes will be classified and defined in order to guarantee the safety and proper functioning of the installation. Finally, an economic study is carried out and the NPV and Payback Period are calculated to verify that the project is economically viable.