EPA Agreement Number: R82-7015-010
Title: Data for Design of Vapor Recovery Units for Crude Oil Stock Tank Emissions
Investigators: R. E. Babcock
Institution: University of Arkansas
EPA Project Officer: Bala Krishnan
Project Period: January 27, 2003 - August 30, 2003
Research Category: Pollution Prevention
Hydrocarbon emissions from petroleum field stock tanks provide a nuisance because of smell and in rare cases, even in the absence of hydrogen sulfide, actually create an identifiable health hazard. The June 17, 1999 regulations issued by EPA call for control systems to reduce emissions by 95% on stock tanks containing API gravity oil greater than 40" and having a gas-oil ratio (GOR) greater than 1750 SCF/STB. Emission control is desirable on stock tanks fluids with less volatility than those that fall under the promulgated national standards because of odor and loss of saleable product. Vapor recovery units (VRU=s) are now available from vendors for capturing 95% of the emissions from stock tanks, but close tolerance on the design of such units is required to be cost effective. Economic driven is preferred to regulation driven.
This project will develop a model for accurately quantifying actual stock tank emissions from Adead oil@ (emission rate < 10 lb/hr) stock tanks. The model will be compared to measured emission rates from three site visits to three different gravity lease sites under varying climatic conditions. This model will then be used to design lease-site specific VRU=s followed by a sensitivity analysis of the economic feasibility of the units as a function of the accuracy of the emission vapor design parameters. The overall objective of the project will be to present a protocol for evaluating the economic feasibility of capturing and utilizing stock tank emissions from a particular lease site. The protocol will only use data that is routinely available for lease sites and the target cost of the evaluation is $1000 per site.