ORC SYSTEM USING R1233ZD(E) FOR WASTE HEAT RECOVERY FROM THE UPSTREAM PROCESS

Abstract

The upstream is an energy-intensive sector of the petroleum industry. Nearly one-third of the industry's energy is discharged as thermal losses via cooling systems or into the environment. Waste heat recovery (WHR) from upstream processes could significantly reduce current fossil energy's carbon footprint and competitiveness and stimulate the transition to carbon-neutral renewable energy sources by utilizing the free energy generated from WHR to support renewable energy production. In the WHR system, the working fluid selection is critical to the design, thermodynamic performance, operation practicality, and environmental impact of organic Rankine cycles (ORC). This study comparatively examined the ORC performance of six working fluids (easily accessible in Malaysia) for WHR from upstream processes using a thermodynamic model. Results showed that R1233zd(E) is a promising working fluid for WHR due to its zero Global Warming Potential (GWP). The single-loop ORC cycle using R1233zd(E) delivered 6.2% thermal efficiency at a 250°C temperature difference by maintaining an operating pressure ratio of 9:1. These conditions ensured a practical turbine expander design for mechanical work recovery. The WHR process reduced the overall carbon footprint of the upstream product by 6.2%.