(556e) Tracking of Flare Streams Emissions and Tax Implication during Process Abnormal Situations

Upset flaring is the controlled burning of gas stream that cannot be processed due to a disturbance within the steady state process which leads to abnormal situation. The main concern with flaring is its contribution to global climate change due to GHG formation during the combustion process. Global Gas Flaring Reduction (GGFR) public-private partnership reported that flaring gas emits about 390 million tons of CO2 annually. Countries who have signed on with GGFR and other environmental regulatory authorities are concerned with reducing the GHG emissions footprint that results from flaring. Hence there is a need for, a standard, reliable and consistent approach to quantify GHG emissions. These values will be used to report to regulatory agencies; and furthermore such estimation methods will be very useful in assessing potential flare reduction mitigation methods. The aim of this work is to illustrate systematic procedure for estimating Carbon dioxide (CO2) and Carbon dioxide equivalent (CO2-e) of process upset flares based on standard published Global Warming Potential (GWP) values. The merit of the CO2 calculator is that it has the ability to estimate CO2 emissions for different process upset scenarios while each scenario has multiple known flare sources. As a part of carbon emissions reduction motivation, this CO2 calculator is able to estimate the carbon tax and credit using the latest carbon tax rates at various focal countries around the globe. The calculator is developed as part of an ongoing project that studies and develops mitigation methods for flare reduction during process upsets. In this paper the base case ethylene process is studied and simulated. The process prevalent flare sources during normal and abnormal (upset) operations are highlighted. The calculator is used to assess the process emissions during normal and during abnormal situations; in addition, the calculator was integrated with an optimization framework used to asses the impact of two proposed mitigation techniques for flare utilization. The calculator was useful in assessing both the environmental and economic implications of the studies cases.