(82b) Energy Efficient Design of Industrial Processes through Life Cycle Cost Optimization

Industrial sectors account for about one third of global energy consumption which rely on fossil fuels as the primary source of energy. A large portion of the energy consumption is spent on production of utilities for the process plants to produce energy for other sectors. Due to the impacts of fossil fuel combustion on the environment lots of effort are made to minimize it and also environmental regulations are affecting the cost of energy to produce it. Furthermore, this is competitive world and with ever increasing energy prices the industrial communities are invited to conserve energy resources. It is common to find options for process changes in a production process and identify opportunities to reduce the operating and capital costs. Designing any system have many constraints and the challenge is to utilize the imposed constraints in a way to improve the system efficiency. Proper utilization of system design constraint along with the available technology can lead to efficient system design which provide many options for optimization. All system design is defining its efficiency by operation, the best operation can achieve/approach to the design efficiency but you cannot improve further without changing the system design. So, if a system is designed for higher efficiency will perform always superior that an inefficient designed system. Hence, it is very important to optimize the new facility design and develop methodology to investigate all possible alternatives during the design stage of the project. In this paper, optimization of the new facility design with simultaneous process and utility integration is demonstrated by conducting energy optimization assessment for one of the upcoming facilities during DBSP phase of the project. The objective of the assessment is to optimize the project life-cycle cost by assessing and examining all technical feasible design alternatives. The new facility is installation of additional units in the existing natural gas processing plant. Natural gas processing plants require a series of process units to remove contaminants such as water, carbon dioxide and hydrogen sulfide. These units have different process heating and cooling demands. Proper matching of the heating and cooling requirements leads to significant operating cost reductions. Excessive heat from process units can be recovered which may be used for satisfying heating requirements of other units or for power generation. The purpose of the new facility is to install dew point control unit, de-ethanizer and condensate stripper to meet the required products specification. The assessment results in energy and capital savings as well as GHG reduction and also assure that the new facility design is energy efficient while satisfying all intended objectives.