0900. diverting FOGs from wastewater stream for biodiesel ......consumption for biodiesel made from trap grease • Typically the energy consumption of trap grease biodiesel is lower

Diverting FOGs from Wastewater Stream for Biodiesel Production

by:

Qingshi TuPhD student in Environmental Engineering

University of Cincinnati

Ohio WEA-AWWA 2014 Technical Conference & ExpoColumbus, Ohio August 26-29, 2014

Agenda• Problem statement

– Fats, oils and greases (FOGs): issues & opportunities

• Research focus– Technical innovations– Life cycle assessment (LCA)

• Summary• Acknowledgement• References

Problem Statement

Sewer Grease

Trap Grease

Treated in wastewater treatment plants

Collected by grease haulers Landfill

Problem Statement• Significant generation: 3,800 million lbs produced

annually in US (Tyson, 2002)

• Environmental nuisance: −Clogging pipes overflow, corrosion−Landfill burden

• Economical concerns: clean-up and maintenance costs

• Social impacts: odor, contamination, inconvenience

Problem Statement

• Strategies to address the problem:−Reduce waste FOG generation− Improve monitoring−Alternative disposal approaches

• FOG-to-Biodiesel: −Renewable fuel, compatible with diesel engine −Large potential: > 400 million gal/year −Revenue: Renewable Identification Number (RIN)

~$0.3/gal

Problem Statement

• Challenges: −Difficulty in separation: FOGs entrapped in the

scum−Degraded FOGs: contains high concentration of

free fatty acids (FFA)impacts biodiesel yield and cost

−Energy efficiency of the process?−Environmental impacts?

Structure of the PresentationProblem

statement

Technical innovations

In-situ conversionGlycerolysis

LCA

LC energy consumption

Environmental impacts

Structure of the presentation

Problem statement



LCA



Structure of the proposal

Technical Innovations

Technical Innovations

11

Trap Grease Sewer GreaseDecanted FOG Entrapped FOG

Up to 60% FFA Difficult to separate FOG

Challenge to address:Reducing FFA

Challenge to address:Separating FOG

Glycerolysis “In-situ Conversion”

Problem statement



LCA




http://www.intechopen.com/

High FFA concentration in trap grease leads to:

• Soap formation

• Waste of catalyst

• Reduced yield

• Increased process costhttp://biodiesel.infopop.cc

Glycerolysis

Glycerolysis•Glycerol is a by-production from biodiesel production•Glycerol sales price is decreasing

GlycerolysisEsterification Glycerolysis

# of steps ≥2 1

Temp. low high

Chemicals H2SO4, MeOH glycerol

Separation MeOH/Water NA

• Goal of this study– Reduce FFA% in FOGs derived from trap grease– Novel catalyst production– Parametric analysis and optimization

Glycerolysis

• Materials– Trap grease: obtained from local food processer– Synthetic high FFA oil: oleic acid + waste cooking oil– Crude glycerol: lab-scale biodiesel production– Other chemicals: Fisher Scientific®

• Analytical methods– FFA measurement: AOCS Cd 3d 63– Glycerol purity: modified AOCS method Cc 17-79 (van

Gerpen et al., 2004)

Methodology

Methodology• Preparation of catalyst

– From chemicals (Macierzanka and Szelag, 2004)

– From solids in trap grease• Determine the amount of residual FFA and oil• Calculate the NaOH to saponify the residual FFA and

oil

Left: ZnC Right: ZnC from solids

• Experiment series– Synthetic high FFA oil w/o

catalyst– FOGs w/o catalyst– FOGs w/ catalyst– FOGs w/ catalyst (derived

from solids)

Methodology

Experimental Setup

• Experiment matrix (synthetic high FFA oil)

Methodology

Parameter -1 +1

Gly-FFA molar ratio 1:1 2:1

Temperature 160C 200C

Time 3 hr 6 hr

Glycerol Pure Crude

• Experiment matrix (other experiments)

Methodology

Parameter Value

Gly-FFA molar ratio 1:1

Temperature 200/240°C

Time 3 hr

Glycerol Crude

Catalyst-FFA molar ratio 0.025-0.2:1

• Synthetic high FFA oil w/o catalyst

Preliminary Results

Range of FFA reduction:50.00%-99.49%

Preliminary Results

ExperimentSeries

3-hr FFA Reduction (%)

Catalyst-FFAmolar ratio Temperature (°C)

Synthetic high FFA oil 22.22-82.86 NA 160/200

FOG w/o catalyst 74.66-97.65 NA 200/240FOG w/ catalyst 80.57-87.33 0.025-0.2 200FOG w/ catalyst

(from solids) 80.57-86.45 0.025/0.05 200

Section Summary

• Temperature and time are the most influential parameters

• Catalyst made from trap grease solids can reduce the reaction time and temperature

• Future work– Improve catalyst production process (e.g. time, doses of NaOH

and ZnSO4)– Parametric optimization of glycerolysis: time, temperature and

dose of catalyst

Problem statement



LCA




In-situ Conversion

(http://409g4.wikispaces.com/%E2%97%8F+Production+(Biodiesel))

Lam et al. 2010

1) Acid-catalyzed transesterification

2) Acid-catalyzed esterification

• Materials– Sewer grease samples: collected from the skimmers

in the a local WWTP and dried in air for weeks before sent to UC

– Sample pretreatment: heating at 105 °C in the oven for 24 hours remove the moisture

– Chemicals: Fisher Scientific®

Methodology

Hard to separate

FOG

• Analytical methods– FFA: AOCS Cd 3d 63– Oil content (tri-/di-/mono-glycerides): GC/FID ASTM D 6584 – 00

– FAME: GC/MS Restek Rxi®-5ms (Bellefonte, PA) column (30 m,

0.25 mm i.d., and 0.25 μm df)

Methodology

• Experimental Procedure– Preheat and mix the MeOH and

H2SO4

– Add 10 g sewer grease into the liquid mixture

– After reaction, let the mixture settle and filtrate out the solids

– Transfer liquid phase to a rotary evaporator for MeOH recovery

– Remaining liquid is taken up by 25 ml hexane and transfer to a vial for analysis

Methodology

Reactor setup

• Experimental matrix

Methodology

ParameterLevel

- +

Temperature (°C) 55 65

MeOH-to-sewer Grease Ratio (v/wt) 5:1 10:1

H2SO4 % (wt%) 25% 50%

Duration (hr) 2 4

• Characterization of sewer grease samples

Preliminary Results

Properties ValueC (%) 74.36H (%) 12.47N (%) 0.2S (%) 0.14O (%) 8.91

Ash (%) 3.92HHV (Btu/lb) 15,083

Ultimate Analysis

Composition ValueMoisture (%) 49.39

Oil (%) 13.10

FFA(%) 12.64Solids (%) 24.87

Composition Analysis

* Done by a third-party analytical lab

Composition ValueOil (%) 25.88FFA (%) 24.98

Oil+FFA (%) 50.86Solids (%) 49.14

• FAME + oil concentration in the final product

Preliminary Results

* average=11.88% of dry TG

Section Summary• Under selected experiment conditions:

– FAME in the final product: 8.27% of dry sewer grease

– Total converted and extracted (FAME+oil) in the final product:

20.15% of dry TG

– Hydrolysis may be necessary to convert oil into FFA to

expedite the reaction

– Parameter optimization is necessary to improve the formation

of FAME

Section Summary

• Future Work−Test hydrolysis pretreatment

−Alter the 24 full factorial experiment design

−Analyze the impact of each parameter and their

interactions on the in-situ reaction

−Optimize the parameters

Problem statement



LCA




LCA

(ISO 14040, 2006)

Problem statement



LCA

LC energyconsumption



• Goal– Assess life cycle energy consumption for trap

grease biodiesel production– Investigate the influence of input variables

• Scope− “Gate-to-gate”− Functional unit: 1 gal BioD

37

Goal and Scope

Approach and Assumptions• Process model for each stage is derived from

references• Material and energy inputs are based on the

regression of data from corresponding references• Assume “perfect” applicability of the model and

regression equations • Life cycle energy (indirect energy included) for

material and energy inputs

Data Source– Transportation stages: grease haulers, MSD– FOG separation stage: personal communication with experts,

journal papers and reports, and online resources– FOG treatment stage: journal papers and reports– Biodiesel production stage: journal papers and reports– Anaerobic digestion stage: journal papers and reports

Process Description (FOG separation)

Energy input:• Heat generated by burning natural gas to facilitate the separation• Electricity to support the transfer of raw trap grease through the systemMaterial input: raw TG

Process Description (Esterification)

Energy input:• Heat generated by burning natural gas to recover the excessive MeOH and to maintain the temperature of the reaction system

• Electricity to support operation of the systemMaterial input:FFA, MeOH, H2SO4, NaOH

Process Description (BioD Production)

Energy input:• Heat generated by burning natural gas to recover the excessive MeOH and to maintain the temperature of the reaction system

• Electricity to support operation of the systemMaterial input:FOG, MeOH, HCl, NaOCH3

Process Description (AD & Transportation)Transportation Distance (miles)

Restaurant-to-hauler’s facility

150

Hauler’s facility-to-WWTP 47.4

WWTP-to-landfill 100

http://www.wtert.eu/default.asp?Menue=13&ShowDok=17

Results and Discussion (Baseline Case)



Results and Discussion (Comparison w/ Existing Studies)

Results and Discussion (Sensitivity Analysis)

Results and Discussion (Sensitivity Analysis)

Results and Discussion (Monte Carlo)

• Randomization of variables (e.g. FOG concentration) based on their cdfs

• Generate a range of results • Offer options to evaluate the process based on

possibilities• Construct MC model in PythonTM

• 10,000 lbs raw trap grease• x10,000 runs

Section Summary• Utilizing the solids for AD is vital to reducing the energy

consumption for biodiesel made from trap grease• Typically the energy consumption of trap grease

biodiesel is lower than that of biodiesel made from other feedstocks

• CH4 generation rate, FOG% and FFA% are the three major factors that influence the energy consumption

MJ/gal 5th % 25th % 50th % 75th % 95th %w/ AD -822.05 -21.84 19.36 32.83 47.61w/o AD 3.76 44.65 52.66 62.77 88.12

Problem statement



LCA




TG LC Environmental Impact• Goal:

– GHG inventory– Major impact categories: global warming potential

(GWP), acidification potential (AP), ozone depletion potential (ODP), and eutrophication potential (EP)

• Scope:– Same as TG LC Energy

• Software: OpenLCA®

• Emission inventory– National Renewable Energy Laboratory’s (NREL) U.S. Life Cycle

Inventory database– LCA reports from national laboratories, research institutes and

peer-reviewed journal articles

• Characterization factors: – Tool for the Reduction and Assessment of Chemical and Other

Environmental Impacts (TRACI)– ReCiPe

• Sensitivity analysis and MC

Methodology

Summary of the Presentation • Several research projects tied together to

promote FOG-to-Biodiesel practice• Technology development to improve the FOG-

to-biodiesel process• Assess the life cycle energy consumption and

environmental impacts of the trap grease-to-biodiesel process

AcknowledgementFunding support:• US EPA’s P3-“People, Prosperity, and the Planet”

Student Design Competition for Sustainability (Phase I-SU836038; Phase II-SU835291)

In-kind support:• Metropolitan Sewer District of Greater Cincinnati• Bluegrass Biodiesel®

AcknowledgementDr. Mingming Lu (academic adviser), Univ. of CincinnatiDr. Drew C. McAvoy, Univ. of CincinnatiDr. Ting Lu, Black & VeatchBryant McDonnell, ArcadisDr. Ming Chai, Greenleaf Biofuels… and many more…

ReferencesAgnew R, Chai M, Lu M, Dendramis N (2009) Making biodiesel from recycled cooking oil generated in campus dining facilities. Sustainability 2: 303-307.Agriculture Marketing Resource Center (AgMRC). Soybean oil and biodiesel usage projects & balance sheet. http://www.extension.iastate.edu/agdm/crops/outlook/biodieselbalancesheet.pdf, accessed on Oct. 2013.Alternative Fuels Data Center (AFDC). http://www.afdc.energy.gov/laws/matrix/tech, accessed on Oct. 2013.Austic, G. 2010. Evaluating the profitability of a trap effluent dewatering facility in the Raleigh area. http://www.biofuels.coop/wp-content/uploads/2011/02/ECO-Collections-trap-grease-feasibility.pdf, accessed on May, 2011.Canakci M (2007) The potential of restaurant waste lipids as biodiesel feedstocks, Bioresource Technol 98: 183-190.Canakci, M., and van Gerpen, J. 2003. A pilot plant to produce biodiesel from high free fatty acid feedstocks. Transactions of the ASAE. 46 (4), 945-954.Canoira, L., Rodríguez-Gamero, M., Querol, E., Alc_antara, R., Lapuerta, M., and Oliva, F. 2008. Biodiesel from low-grade animal fat: Production process assessment and biodiesel properties characterization. Ind. Eng. Chem. Res. 47, 7997–8004.Cassman, KG., Liska, A.J. 2007. Food and fuel for all: realistic or foolish? Biofuels, Bioproducts and Birefining. 1(1): 18-23.Chakrabarti, A. R., Hake, J. M., Zarchi, I., Gray, D. M. D. 2008. Waste Grease Biodiesel Production at a Wastewater Treatment Plant. WEFTEC Report, 2770-2789.Dagher, M., Panicker, R., Myles, E., Bell, N. 2004. Mississippi biodiesel feasibility study. http://www.southeastdiesel.org/Photos/Library/Ag/AlcornSec3_Report.pdf, accessed on Oct. 2013.Diaz-Felix W, Riley MR, Zimmt W, Kazz M (2009) Pretreatment of yellow grease for efficient production of fatty acid methyl esters Biomass Bioenerg 33: 558-563.Eastern Municipal Water District. Biodiesel production from grease waste. http://www.emwd.org/modules/showdocument.aspx?documentid=94, accessed on March 2012.Energy Information Adminstration (EIA). 2004. Biodiesel performance, costs, and use. http://www.eia.gov/oiaf/analysispaper/biodiesel/, accessed on Oct., 2013.Energy Efficiency and Renewable Energy (EERE). “Energy cost calculator for air-cooled electric chillers”. http://www1.eere.energy.gov/femp/technologies/eep_ac_chillers_calc.html, accessed on March 2012.Haas, M. J. 2010. Alternate feedstocks and technologies for biodiesel production. IN: the Biodiesel Handbook, 2nd edition, AOCS publishing, Urbana, IL. pp. 47-66.Harris, A. 2009 Food for fuel. Engineering & Technology. 4 (19): 53.Hass, M. J. 2011. Extraction and use of DDGS lipids for biodiesel production. In: “Distillers grains: production, properties, and utilization”. CRC Press, Baca Raton, FL. pp 487-502.Huo, H., Wang, M., Bloyd, C. and Putsche, V. 2008. Life-cycle assessment of energy and greenhouse gas effects of soybean-derived biodiesel and renewable fuels. ANL/ESD/08-2. Argonne National Laboratory, Argonne, IL. King, C.W., and Webber, M.E. 2008. Water intensity of transportation. Environ Sci & Technol 42, 21: 7866-7872.Kulkarni MG, Dalai AK (2006) Waste cooking oil - An economical source for biodiesel: A review. Ind Eng Chem Res 45: 2901-2913.Lopez, D.E., Mullins, J.C., and Bruce, D.A. 2010. Energy life cycle assessment for the production of biodiesel from rendered lipids in the United States. Ind. Eng. Chem. Res. 49, 2419-2432.Menendez, M.R. How we use energy at wastewater plants…and how we can use less. http://www.ncsafewater.org/Pics/Training/AnnualConference/AC10TechnicalPapers/AC10_Wastewater/WW_T.AM_10.30_Menendez.pdf, accessed on March 2012.National Biodiesel Board (NBB). Production statistics. http://www.biodiesel.org/production/production-statistics, accessed on Oct. 2013.New York City Department of Environmental Protection. 2010. Preventing Grease Discharges into Sewers. http://www.nyc.gov/html/doh/downloads/pdf/rii/prevent-grease-discharge-sewers.pdf, accessed on Dec. 2012.North Carolina (NC). 2002. Considerations for the Management of Discharge of Fats, Oil and Grease to Sanitary Sewer Systems. http://infohouse.p2ric.org/ref/20/19024/19024-1.pdf, accessed on Dec. 2012.Orange County. 2004. Fact Sheet: Fats, oils and Grease (FOG) Source Control Program. www.ocsd.com/civica/filebank/blobdload.asp?BlobID=6523, accessed on Dec. 2012.Pradhan, A., Shrestha, D.S., McAloon, A., Yee, W., Haas, M., and Duffield, J.A. 2011. Energy life-cycle assessment of soybean biodiesel revisited. Transactions of the ASABE. 54, 3, 1031-1039.Pradhan, A.; Shrestha, D. S.; Van Gerpen, J.; and Duffield, J. 2008. The Energy Balance of Soybean Oil Biodiesel Production: A Review of Past Studies. Trans. ASABE. 51 (1), 185–194.San Francisco (SF) Water, Power, and Sewer. 2011. Brown grease to biodiesel demonstration project. http://www.sfwater.org/modules/showdocument.aspx?documentid=1540, accessed on Dec. 2012.Services of the San Francisco Public Utilities Commission (SFPUC). Brown grease to biodiesel demonstration project. http://www.sfwater.org/modules/showdocument.aspx?documentid=1540, accessed on March 2012.Sheehan, J., Camobreco, V., Duffield, J., Graboski, M., and Shapouri, H. 1998. Life cycle inventory of biodiesel and petroleum diesel for use in an urban bus. National Renewable Energy Laboratory, NREL/SR-580-24089.Sills, D.L., Paramita, V., Franke, M.J., Johnson, M.C., Akabas, T.M., Greene, C.H., and Tester, J.W. 2013. Quantitative uncertainty analysis of life cycle assessment for algal biofuel production. Environmental Science & Technology. 47, 687-694.Tashtoush G.M., Al-Widyan, M.I., Al-Jarrah, M.M. 2004. Experimental study on evaluation and optimization of conversion of waste animal fat into biodiesel. Energy Conversion and Management. 45: 2697-2711.Tu, Q., Chai, M., Lu, M., Yang, Y.J.. 2011. Kinetic study on the acid catalytic esterification of high level free fatty acids in the waste cooking oil. A&WMA 104th Annual Conference and Exhibition, June 21- 24, Orlando, Florida, 2011.Tu, Q., Wang, J., Lu, Ml, Chai, M., Lu, T. 2012. Feasibility and practices of making biodiesel out of low quality greases. EM. January Issue, pp26-29.Turner, N. B., Landsburg, E. B., Feldman, E., Varghese, A. R., Blaza, G. 2011. Beneficial reuses of sewer grease: biodiesel production vs. anaerobic digestion. Paper 2011-A-627-AWMA. Air & Waste Management Association 104th Annual Conference, Orlando, FL.AND MORE….

THANK YOU!

QUESTIONS?

Qingshi [email protected]

Documents

0900. diverting FOGs from wastewater stream for biodiesel ......consumption for biodiesel made from trap grease • Typically the energy consumption of trap grease biodiesel is lower