Innovative Biological Emissions Treatment Technology to Reduce Air Pollution for Petroleum and Petrochemical Operations

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1 1/31/2017 Kim Jones, David Ramirez, Shooka Khoramfar Department of Environmental Engineering, Texas A&M University-Kingsville, Kingsville, TX 78363, USA Project consultant: James Boswell, Boswell Environmental, Montgomery, Texas Project Sponsor: Carolyn LaFleur, Houston Advanced Research Center (HARC) Project partners: George King, Sam Pittman, Cody Garcia, Apache Resources Production Facility Innovative Biological Emissions Treatment Technology to Reduce Air Pollution for Petroleum and Petrochemical Operations

2 Potential opportunities for biological air emission control Waste Water during Drilling, Fracturing and Natural Gas Production Process equipment such as Compressors and motors on the drilling and production sites Condensate storage tanks Based on Occupational Safety and Health Administration (OSHA), permissible exposure limit (PEL) (8 h TWA) of benzene for general industry = 1.0 ppm 2

3 Why biological treatment? Biological treatment of air emissions offers a cost-effective and sustainable control technology for industrial facilities facing increasingly stringent air emissions limits. This system uses the capacity of microorganisms to degrade air toxins (HAPs, Hazardous Air Pollutants), like benzene without the use of natural gas as fuel or the creation of secondary pollutants. The replacement of conventional thermal oxidizers with biofilters will yield natural gas savings alone in the range of thousands of dollars to over $1 million per year per unit. Any new technology that could replace a single thermal oxidizer (100,000cfm size) could provide a savings of more than 4,166 MM BTUs of natural gas annually (based on 8,760 hrs of operation and MM BTU per hour of usage). That represents enough natural gas to comfortably heat or cool approximately 120 homes annually for each thermal oxidizer or flare replaced. Water vapor, carbon dioxide and biomass are the products of aerobic biodegradation of organic pollutants. However, the carbon emissions in biologically based units is much less than incinerators and flares. 3 (Source: Boswell, 2008)

4 Successful pilot scale sequential treatment for VOC emissions at different industries Forest product plant, Stimson Lumber Co. Gaston, Oregon Paint & Coatings Eugene, Oregon 4

5 Process description The goal of this project is to demonstrate a novel sequential treatment technology that integrates two types of bio-oxidation systems biotrickling filter and fixed bed biofilter for controlling petrochemical industries air emissions. This coupled design can be optimized to maximize the conditions for microbial degradation of VOC vapors. The first bed takes the highest inlet VOC loadings, to remove the more water soluble organics, while the secondary bed acts as an overload and polishing stage to remove more complex organic compounds. The first unit also controls the incoming air stream temperature and regulates humidity and dampens fluctuations in contaminant loadings. Less hydrophobic pollutants can be removed in the first stage Bio-trickling Chamber by the biofilm on the surfaces of the X-Flow media and microbes in the sump and more hydrophobic compounds should be removed within the Bio-Matrix Chamber periodically sprayed with sump water to maintain proper moisture for best biofilm development. Water entering the biotrickling filter is collected in a sump, monitored for water quality parameters, and continuously sprayed onto the top of the X-flow media bed in the BTF. The flowing water phase benefits the biotrickling filter by providing a continuous supply of nutrients, removing possible degradation by-products, suspending biomass for continual reseeding of the system, and aiding in the transfer of hydrophilic pollutants onto the biofilm. 5

6 Objectives for the Apache (TAMU #2 tank battery) field test 1 Sampling and characterization of some field VOCs emissions 2 Design, build, process test and implementation of a field scale sequential treatment unit in 12 months 3 Demonstrate the ability of bio-oxidation systems to treat variable loadings of VOC emissions as experienced in refineries and production facilities during routine operations, process turnarounds or upsets 4 Optimize the process for the ability to efficiently degrade mixtures of hydrophobic compounds typically encountered in refinery and oil and gas production facility emissions 6

7 Characterization of VOCs GC-FID PID GC-MS 7

8 Biotrickle filter media (First vessel) 8

9 Biofilter media (Second vessel) 9

10 Key design and operational parameters Temperature ph and Conductivity Nutrient concentration Water flow rate Pressure Air flow rate Key design and operational parameters Biofilter bed moisture 10

11 Field scale unit start up at Apache TAMU #2 tank battery- 10 May 2016 to 1 August 2016 The field unit consists of a skid mounted two vessel system (100 cubic feet of total treatment volume) made of fiberglass with corrosion resistant schedule PVC piping (Diamond Fiberglass Fabricator, Victoria, TX).

12 Field scale unit start up at Apache TAMU #2 tank battery- 6 May

13 Field scale unit start up at Apache TAMU #2 tank battery- 28 April 2016 to 30 May Date Completed task 04/28/16 Load the BF media to the second vessel 05/05/16-05/25/16 Safety meeting, Generator set up, Sampled of the headspace for GC-MS analysis, Loaded the BTF media to the first vessel, Checked the immediate area around the system for hydrocarbon content with a photoionization detector (PID), Inoculation of the system with oily water and compost tea, Checked the water pump and blower performance 05/30/16 Inoculation of the system with the CITGO s Corpus Christi Refinery wastewater 13

14 Main dimensions and characteristics of the two tanks BTF Bed height (ft) 4 4 Diameter (ft) 4 4 Ratio height to diameter 1 1 BF Recirculation tank volume (gal) Water make-up tank volume (gal) 300 Air flow rate (ft 3 /min) Recirculation flow rate (gal/min) 3.5 (optimization possible) 3.5 (optimization possible) Spraying frequency 24/7 2 min every 8 hr (optimization possible) Gas velocity, (ft/min) EBRT (min) 2 (optimization possible) 2 (optimization possible) 14

15 GC-MS characterization from the headspace of the Apache TAMU #2 tank battery Peak # Component Retention Time Conc. (ppm) 1 Butane Isobutane Pentane Butane, 2-methyl Hexane Pentane, 2-methyl Cyclohexane, methyl Heptane Cyclopentane, methyl Toluene Octane Benzene Nonane p-xylene

16 Fluctuation in VOC concentration at inlet of the bio-oxidation unit 1 August Apache TAMU #2 tank battery VOC (ppm isobutylene equivalent) :24 AM 9:36 AM 10:48 AM 12:00 PM 1:12 PM 2:24 PM 3:36 PM Time 16

17 PID measurements from the inlet and outlet of the bio-oxidation unit- 10 May 2016 to 29 July Apache TAMU #2 tank battery VOC (ppm isobutylene equivalent) May 20-May 30-May 9-Jun 19-Jun 29-Jun 9-Jul 19-Jul 29-Jul Time Inlet Outlet 17

18 Removal efficiency of the biooxidation unit- 10 May 2016 to 29 July Apache TAMU #2 tank battery RE (%) 70% 60% 50% Average RE of the system (July month): 53% Average RE of the BTF (July month): 40% Average RE of the BF (July month): 23% 40% 30% 20% 10% 0% 10-May 20-May 30-May 9-Jun 19-Jun 29-Jun 9-Jul 19-Jul 29-Jul Time BTF removal efficiency Overall removal efficiency BF removal efficiency 18

19 Performance characteristics of the BTF unit using GC- FID- Sampling at 28 July using 3 tedlar bags Inlet Outlet Retention time Compound concentration concentration (min) (ppm) (ppm) RE (%) p-xylene % o-xylene % Benzene % 19

20 Biofiltration Summary In spite of the hydrophobic nature of the pollutants, a relatively high VOC removal was observed in the BTF unit probably due to high biofilm growth and continuous spraying of water and nutrients. BF watering is an important operational parameter since it directly influences the water content and the ph value on the filter media. At the Apache site, given the very warm temperatures during the field biofiltration test, increased irrigation of the BF unit was probably needed. The surprisingly high VOC removal capabilities of the BTF unit suggests that a combination of both suspended growth and attached growth biofilms may provide an important new approach toward biotreatment optimization of VOCs for the oil and gas and petrochemical industries The bio-technology employed in this project may be a cost-effective treatment technique to mitigate VOC emissions from oil and gas facilities and should be evaluated as a possible MACT (Maximum Achievable Control Technology) to control HAPs. 20

21 Next steps To improve the removal efficiency in the bio-oxidation unit, water addition to the system (BTF and BF) should be optimized along with the nutrients concentration. 1. Collecting media samples periodically in order to measure moisture and nutrient concentration of the compost media according to standard methods. 2. Periodically, monitoring ph, conductivity and nutrient (ammonia, nitrate nitrogen, total phosphorus) concentration of the sump. Since the air flow rate or empty bed residence time (e.g. the size of the unit, etc.) will obviously affect the treatment costs, the biooxidation performance will be optimized under various operation conditions. To improve the removal efficiency in the BTF unit for hydrophobic pollutants, addition of surfactants may be tested. 21

22 Implementation of Air Quality Technology for the Oil and Gas Industry in Coastal Areas: Air Emission Measurements and Control Contract No. CITP0910-TAMUK0513B Coastal Impact Assistance Program Investigator: Dr. David Ramirez

23 Project Goal The development and testing of a thermal-swing adsorption (TSA) system to capture and recover toxic air emissions from point sources (storage condensate tanks) Current Practice Proposed TSA System 23

24 Design and Development of TSA System: Phase I Bench Scale 24

25 BTEX Emission Rate (lb/yr) Summary of BTEX Concentrations (ppm) from Bench Scale Condensate Tank with Sample API, 54.2 Summary Benzene Toluene Ethyl m, p- o-xylene benzene Xylene Average Maximum Minimum Comparison of Experimental BTEX Emissions with Simulations from Promax 3.2 and Tanks 4.09D Experiment Tank 4.09d Promax 3.2 Benzene Toluene Ethylbenzene m, p-xylene o-xylene Xylene (m, p and o) 25

26 Effect of Regeneration Temperature on the Liquid Recovery (80-90) C ( ) C Recovered liquid hydrocarbons at regeneration temperatures between C 26

27 Phase II of the TSA System: Pilot Scale Schematic of the 100 slpm-capacity Pilot Scale TSA System 27

28 Phase III of the TSA System: the 3,000 slpm Pilot Scale Unit Pilot Scale TSA System for Continuous Operation 28

29 Phase III of the TSA System: Field Deployment of the 3,000 slpm Pilot Scale Unit Field testing at the Apache site for capturing vapor emissions from the tank battery 29

30 Total Hydrocarbon Concentration (ppmv) Operation Conditions and Removal Efficiencies for the Pilot-Scale TSA Unit During the Field Test Parameter Value Gas stream temperature 110 F Gas volumetric flow rate 142 slpm Inlet concentration Outlet concentration Amount of granular activated carbon in adsorption column 1 Amount of granular activated carbon in adsorption column 2 Removal efficiency of total hydrocarbons before breakthrough 5 kg 8 kg 99.6% Removal efficiency of H 2 S 100% Removal efficiency of CO % Time (min) Adsorption Column 1 30

31 Total Hydrocarbon Concentration (ppmv) Adsorption Breakthrough for the Pilot-Scale TSA Unit During the Field Test: Adsorption Column Inlet concentration Outlet concentration Time (min) 31

32 Next steps The field deployable GC-FID will be used along with the PIDs in order to continuously monitor the concentration of BTEX compounds in the gas phase. We would welcome more opportunities to work with Apache/HARC to optimize our field scale unit for removal of BTEX compounds. Subsequent phases of this project would be optimization of air flow, water flow and residence time for the most effective BTEX degradation for remote oil and gas facilities, and the deployment of more telemetry and modem communication, with a Programmable Logic Controller (PLC) to remotely monitor unit performance and operating conditions. 32

33 Acknowledgements This project was funded by the Houston Advanced Research Center s (HARC) Environmentally Friendly Drilling - Coastal Impacts Technology Program GLO Contract #M11AF00005 Apache Corporation, Houston and Bryan/College Station, Texas Institute for Sustainable Energy and the Environment Texas A&M University-Kingsville (TAMUK) TAMUK team of students Shooka Khoramfar Joshua Robbins Fasae Olusola Erich Potthast Josie Rios 33

34 The environmental crisis is a global problem, and only global action will resolve it. ~ Barry Commoner, biologist Thank you for your attention! 34

35 35

36 Mitigation of Vapor Emissions Preventive Methods Destructive Methods Recovery Methods Source reduction Modifying process Thermal combustion Flaring Catalytic incineration Biofiltration Condensation Membrane separation Absorption Adsorption 36

37 Storage Tank Emissions Oil and condensate tanks are used to store produced liquid at individual well sites. Two primary emission loss are: Flashing loss, condensate brought from down hole pressure to atmospheric pressure may experience a sudden volatilization of some of the condensate Oil and Condensate Tank Battery at Eagle Ford Shale Working and breathing losses, whereby some volatilization of stored product occurs through valves and other openings in the tank battery over time. (TCEQ,2010) Alamo Area Council of Governments Report,

38 VOC Emission Inventory at the Eagle Ford Shale Source Category, Moderate Scenario Source: AACOG,

39 Acknowledgment We would like to thank the Houston Advanced Research Centre for their grant support for this research. Thank you!

40 Recommended exposure limit guidelines for benzene in ambient air Name of agency Parameter Concentration American Conference of Governmental Industrial Hygienists (ACGIH) Threshold limit values (TLV) Short-term exposure limit (STEL) 0.5 ppm 2.5 ppm National Institute for Occupational Safety and Health (NIOSH) Occupational Safety and Health Administration (OSHA) Environmental Protection Agency (EPA) (Source: Recommended exposure limit (REL) based on 10-h time weighted average (TWA) STEL Immediately dangerous to life or health (IDLH) Permissible exposure limit (PEL) (8 h TWA) for general industry Inhalation reference concentration (RfC) 0.1 ppm 1.0 ppm 500 ppm 1.0 ppm 0.03 mg m -3 Inhalation unit risk 2.2x xl0-6 μg m -3 40

41 Available technologies for removal of VOCs Many processes and technologies have been developed to control VOCs emission. There are six main processes by which a gaseous pollutant may be removed from an air stream. Biotreatment Absorption (wet scrubbing) Carbon Adsorption Condensation Thermal incineration Flares 41

42 Description of available technologies for removal of VOCs In the case of absorption, the target pollutant is transferred to the scrubbing solution. Recovery of the solvent might be undertaken by distillation or by stripping the absorbed materials from the solvent. Adsorption is an efficient technique for the treatment of low concentration of VOCs where pollutants get adsorbed onto the surface of activated carbon or zeolites which are used as adsorbents. Adsorption can provide the means for the materials to be more readily recovered. Condensation is preferable at high pollutant concentration where waste gas treatment involves recovery of some valuable solvents from the concentrated waste streams. The VOCs are partially recovered by simultaneous cooling and compressing the gaseous vapors. For organic pollutants when the concentration is low or recovering the material is not desired, incineration at high temperatures ( C) or in the presence of a catalytic such as platinum ( C) can be used to convert the pollutant to carbon dioxide and water. For large emissions such as those found in petroleum refineries the pollutant may be flared. 42

43 Technology Advantages Disadvantages Biotreatment Absorption (Wet Scrubbing) Simple and low cost (capitol, operational and maintenance) technology Low energy requirement, no fuel needed Effective removal of odours and VOCs Environmentally friendly without production of by-products Low carbon emissions Medium capital costs Relatively small footprint Ability to handle particulate and variable loads of the gas stream Difficulty in control of ph and moisture in biofilters Relatively large footprint Clogging and pressure drop due to extensive growing of biomass Very high operating costs Not effective for most of the VOCs Toxic and complex chemicals requirement Carbon Adsorption Incineration Medium capital costs Small footprint Reliable operation Small footprint Reliable and uniform performance for relatively all compounds irrespective of nature and concentration High operating costs Reduced carbon life due to the moisture of the gas stream Creates secondary waste stream due to spent carbon High operating and capital costs Huge amount of investment in fuel cost Creates secondary waste stream (Nox) 43

44 How it works? In the biofiltration process, contaminated air is moistened and is pumped into the biofilter. While the air slowly flows upward through the filter media, the contaminants in the air stream are absorbed and metabolized by the microorganisms. The purified air passes out of the top of the biofilter and into the atmosphere. Most biofilters that are in operation today can treat odor and VOCs at efficiencies greater that 90%. The technology is best suited to treat relatively low concentrations of pollutants (<1000 ppm) and loading rates between ft 3 /ft 2 -hr. 44

45 Schematic of the unit 45

46 Sampling of VOCs Tedlar bag sampling 46

47 Elimination capacity vs. pollutant loading rate- Apache TAMU #2 tank battery Elimination capacity (g/m 3.hr) Initial loading rate (g/m 3.hr) 47

48 Optimization of the BTF-BF unit for removal of hydrophobic pollutants Application of fungi 48

49 Cont Application of surfactants 49

50 Controlling instruments Water flow rate Air flow rate and Temperature Pressure gauges ph and Conductivity Biofilter bed moisture Nutrient concentration 50