Locating Oil-Water Interfaces in Process Vessels

EPA Grant Number: R827015C015
Subproject: this is subproject number 015 , established and managed by the Center Director under grant R827015
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: IPEC University of Tulsa (TU)
Center Director: Sublette, Kerry L.
Title: Locating Oil-Water Interfaces in Process Vessels
Investigators: LoPresti, Peter G. , Manning, Francis S.
Institution: University of Tulsa
EPA Project Officer: Lasat, Mitch
Project Period: June 14, 2001 through November 30, 2001
RFA: Integrated Petroleum Environmental Consortium (IPEC) (1999) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , Targeted Research

Objective:

Crude oil is always produced with connate water, and the water-to-oil ratio is often greater than 10 to 1. In the field, the well stream is first separated into its three phases: natural gas, crude oil, and produced water. Unfortunately, crude oil and produced water often form stable emulsions that severely impede the oil-water separation. Development of a thick emulsion or rag layer between the oil and water phases is the precursor to an upset. Such upsets reduce production and increase the emissions to land, water and air. The current method of using floats to sense the oil-water interface in separators, treaters, and desalters fails when the emulsion layer thickens.

The current goal is to assess the capability of a new technique for locating the oil/water inferface and measuring the thickness of any rag layer inside production vessels. The technique consists of locating any oil/water or oil/emulsion or emulsion/water interfaces using fiber-optic pressure sensors. The relative amounts of oil and water present at any location can be obtained by calculating the bulk average density form the veritcal pressure profile. In pure water, the pressure increases by 0.433 psi per foot of vertical depth compared to 0.38 psi for a clean 38° API crude oil. Therefore the pressure gradient must be measured to 0.01 psi/ft. Recent work by LoPresti [1, 2] indicates that this can be achieved using fiber pressure sensors.

This work aims at improving the current fiber optic sensors to achieve real-time measurement of the pressure profile in a test column. Differential measurements of pressure will be obtained using the repsonse of fiber Bragg gratings to applied strain. A shift in the wavelength reflected by the grating can be translated into a physical shift in a focused spot of light using a diffraction graing, CCD camera, appropriate optics, and computer processing. Using the appropriate transducers, pressure from the weight of the oil or water can be translated to a fiber strain larger than the rexolution limit of the system.

Supplemental Keywords:

RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Sustainable Industry/Business, Environmental Chemistry, Sustainable Environment, Technology for Sustainable Environment, Analytical Chemistry, Economics and Business, Technical Assistance, Ecological Risk Assessment, Ecology and Ecosystems, pollution prevention, Environmental Engineering, chemical waste, clean technologies, cleaner production, hazardous emissions, petrochemicals, oil production, hazardous waste, pollution control, IPEC, fiber optic pressure sensor, innovative technology, oil water separation, technology transfer, bioremediation

Progress and Final Reports:

  • Final Report

  • Main Center Abstract and Reports:

    R827015    IPEC University of Tulsa (TU)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827015C001 Evaluation of Road Base Material Derived from Tank Bottom Sludges
    R827015C002 Passive Sampling Devices (PSDs) for Bioavailability Screening of Soils Containing Petrochemicals
    R827015C003 Demonstration of a Subsurface Drainage System for the Remediation of Brine-Impacted Soil
    R827015C004 Anaerobic Intrinsic Bioremediation of Whole Gasoline
    R827015C005 Microflora Involved in Phytoremediation of Polyaromatic Hydrocarbons
    R827015C006 Microbial Treatment of Naturally Occurring Radioactive Material (NORM)
    R827015C007 Using Plants to Remediate Petroleum-Contaminated Soil
    R827015C008 The Use of Nitrate for the Control of Sulfide Formation in Oklahoma Oil Fields
    R827015C009 Surfactant-Enhanced Treatment of Oil-Contaminated Soils and Oil-Based Drill Cuttings
    R827015C010 Novel Materials for Facile Separation of Petroleum Products from Aqueous Mixtures Via Magnetic Filtration
    R827015C011 Development of Relevant Ecological Screening Criteria (RESC) for Petroleum Hydrocarbon-Contaminated Exploration and Production Sites
    R827015C012 Humate-Induced Remediation of Petroleum Contaminated Surface Soils
    R827015C013 New Process for Plugging Abandoned Wells
    R827015C014 Enhancement of Microbial Sulfate Reduction for the Remediation of Hydrocarbon Contaminated Aquifers - A Laboratory and Field Scale Demonstration
    R827015C015 Locating Oil-Water Interfaces in Process Vessels
    R827015C016 Remediation of Brine Spills with Hay
    R827015C017 Continuation of an Investigation into the Anaerobic Intrinsic Bioremediation of Whole Gasoline
    R827015C018 Using Plants to Remediate Petroleum-Contaminated Soil
    R827015C019 Biodegradation of Petroleum Hydrocarbons in Salt-Impacted Soil by Native Halophiles or Halotolerants and Strategies for Enhanced Degradation
    R827015C020 Anaerobic Intrinsic Bioremediation of MTBE
    R827015C021 Evaluation of Commercial, Microbial-Based Products to Treat Paraffin Deposition in Tank Bottoms and Oil Production Equipment
    R827015C022 A Continuation: Humate-Induced Remediation of Petroleum Contaminated Surface Soils
    R827015C023 Data for Design of Vapor Recovery Units for Crude Oil Stock Tank Emissions
    R827015C024 Development of an Environmentally Friendly and Economical Process for Plugging Abandoned Wells
    R827015C025 A Continuation of Remediation of Brine Spills with Hay
    R827015C026 Identifying the Signature of the Natural Attenuation of MTBE in Goundwater Using Molecular Methods and "Bug Traps"
    R827015C027 Identifying the Signature of Natural Attenuation in the Microbial Ecology of Hydrocarbon Contaminated Groundwater Using Molecular Methods and "Bug Traps"
    R827015C028 Using Plants to Remediate Petroleum-Contaminated Soil: Project Continuation
    R827015C030 Effective Stormwater and Sediment Control During Pipeline Construction Using a New Filter Fence Concept
    R827015C031 Evaluation of Sub-micellar Synthetic Surfactants versus Biosurfactants for Enhanced LNAPL Recovery
    R827015C032 Utilization of the Carbon and Hydrogen Isotopic Composition of Individual Compounds in Refined Hydrocarbon Products To Monitor Their Fate in the Environment
    R830633 Integrated Petroleum Environmental Consortium (IPEC)
    R830633C001 Development of an Environmentally Friendly and Economical Process for Plugging Abandoned Wells (Phase II)
    R830633C002 A Continuation of Remediation of Brine Spills with Hay
    R830633C003 Effective Stormwater and Sediment Control During Pipeline Construction Using a New Filter Fence Concept
    R830633C004 Evaluation of Sub-micellar Synthetic Surfactants versus Biosurfactants for Enhanced LNAPL Recovery
    R830633C005 Utilization of the Carbon and Hydrogen Isotopic Composition of Individual Compounds in Refined Hydrocarbon Products To Monitor Their Fate in the Environment
    R830633C006 Evaluation of Commercial, Microbial-Based Products to Treat Paraffin Deposition in Tank Bottoms and Oil Production Equipment
    R830633C007 Identifying the Signature of the Natural Attenuation in the Microbial Ecology of Hydrocarbon Contaminated Groundwater Using Molecular Methods and “Bug Traps”
    R830633C008 Using Plants to Remediate Petroleum-Contaminated Soil: Project Continuation
    R830633C009 Use of Earthworms to Accelerate the Restoration of Oil and Brine Impacted Sites