University of Puerto RicoPhysics & Chemistry Department

Renewable Energy : Biofuel Production

Physics & Chemistry DepartmentArecibo

Renewable Energy : Biofuel ProductionKinetic Analysis of Manure Waste Destruction and Biogas

Formation in a Batch Reactor.

5th Forum for Undergraduate ResearchD b 19 2011December 19, 2011

Azgad J Cardona MartiAzgad J. Cardona MartiHéctor E. Claudio Cintrón

Jonathan Reyes ArceLeroy Goñez RodríguezLeroy Goñez Rodríguez

Luis M. Font LewisXioneyl Román González

Advisor: Prof. Hirohito Torres Díaz, PhD,PE

Research ObjectivesResearch Objectives

To determine the biogas production rate (ft3 Biogas/ ft3 digester-day) forrate (ft Biogas/ ft digester day) for different manure waste concentrations.To complete a digester scale up modelTo complete a digester scale-up model to run a 1-HP internal combustion engine.

What is Biogas?What is Biogas?

The bacterial degradation of organic material thatThe bacterial degradation of organic material that produces a gas ( in this case CH4 and CO2), in the absence of oxygen, so it can be used as a fuel source.

AIREXHAUST

BIOGAS INTAKE CHAMBER

POWER KWs

Biogas PropertiesBiogas Properties

Mixture Of Gases:Mixture Of Gases: ~ 40 to 70% of Methane (CH4)~ 30 to 60% of Carbon Dioxide (CO2) 30 to 60% of Carbon Dioxide (CO2)Trace levels of other components such as H2S and NH4H2S and NH4

Biogas Average Density (STD) ≈ 0.074 lbs/ft3

Biogas Average Energy ≈ 560 BTU/ft3Biogas Average Energy ≈ 560 BTU/ftNatural Gas (NG) ≈ 1000 BTU/ft3

Pure Methane ≈ 1200 BTU/ft3

Manure Waste Degradation via an biAnaerobic Process

Dairy WasteT i ll

15%

Typically a cow can produce ≈ 100

lbs/day of manure

15%Total Solid

85% H2O

20% 80%

organicinorganic

12 lbs of 60% of CH4 Biogas ≈ 12.8 ft3/ lbs V.S. For the 100% conversion to

biogas

volatile solid (V.S)

4 g

Experimental Setup for Biogas Generation and Flow Measurement

Gas Bubble Trap (Flapper)Gas Bubble Trap (Flapper)Reed Swich Flapper off

Magnet

Flapper on

BubbleFlapper on

PLC Setup For Biogas Flow Measurements

Flapper Volume CalibrationFlapper Volume Calibration

Flapper Buoyancy Actionpp y y

Experimental Setup for Different Manure Waste Total Solid Concentrations

(Experiments in Duplicates)

Name % of Manure ReactorName % of Manure(TS)

Reactor Volume (L)

Xioneyl 1 % 3

Luis 3 % 3

Leroy 5 % 3

Jonathan 5 % 7

Azgad 10 % 7

Hector 10 % 7

Reactor PreparationReactor Preparation

Basic Concept of Cow ManureBasic Concept of Cow Manure

85% Water

15% Total Solids

Cow Manure “As-Is’’

Reactors to Prepare% TS

Concent. 1% 3% 5% 10%

Volume (L) 3L (duplicate)

3L(duplicate) 7L 7L

(duplicate)

Reactor PreparationExample 3L Reactor at 3% TS

How much water and manure were needed to prepare a 3Lreactor (duplicate) at 3% TS?

1.4 lbs

Manure

Total Weight9.9 lbs Duplicate Reactors at 3% TS

Water from oxidation pond

Actual Total Solids (TS) Vs. E i d V lEstimated Values

V ifi ti f TSVerification of TS

Reactors Concentration Measured Average Concentration

1 0207 % 0 9133 %1%

1.0207 % 0.9133 % 1.0%

1.2251 % 1.2312 % 1.2 %4 3111 % 4 2754 % 4 3 %

3%4.3111 % 4.2754 % 4.3 %

4.2732 % 4.3982 % 4.3 %

5% 5.2772 % 5.4044 % 5.3 %

10%11.8999 % 12.1122 % 12.0 %12.7578% 12.5377 % 12.6 %

Example of Data Gathering and A l iAnalysis

Reactor A 3 % (Flapper Volume = 24mL)Reactor A 3 % (Flapper Volume = 24mL)

Day Flapper Pulse

VolumeVented (mL)

VolumeAccumulated

(mL)Daily Rate Accumulated

Rate(mL) (mL)1 60 1,440 1,440 0.480 0.4802 101 2,424 3,864 0.808 0.6443 109 2 616 6 480 0 872 0 7203 109 2,616 6,480 0.872 0.7204 111 2,664 9,144 0.888 0.7625 94 2,256 11,400 0.752 0.760… … … … … …30 3 72 27,720 0.024 0.308

Summary of ResultsSummary of Results

% 1% 3% 5% 10%Max.

Accumulated Volume

4,296 27,349 111,228 …

Summary of ResultsSummary of Results

Name %Rate *

@ 30 daysRate *

@ 60 days

Xioneyl 1% 0.045 ± 0.036 ------

Luis 3% 0.062 ± 0.215 ------

Jonathan 5% 0.306 ± 0.088 0.110 ± 0.059

AzgadHector

10% 0.392 ± 0.145 0.415 ± 0.140

mLbiogasbiogasft=3

3

* daymLreactordayreactorft −−3

Challenge for Future WorkChallenge for Future Work

Reactor (TS) Rate5% 0.31 ft^3 biogas / ft^3 reactor -day% g y

System ModelyBiogas tube storage

I t k

ExhaustValve

Intake Chamber Engine

a eExhaust

Power (w)

Airvalve

55 gallons drums

Reactors

ConclusionsConclusionsAn experimental setup was configured for the biogas production and fl f llflow measurements successfully. The system currently allows for eight (8) digesters, but based on the PLC I/O cards, it can handle up to 28 digesters simultaneously.Biogas production started immediately (within one day) after mixing manure and water from an oxidation pound.The biogas production for digesters 1% and 3% (TS) ceased at around 30 days. Digesters at 5% and 10% never stopped producing biogas even after 60 days.The biogas production rate (within the range of these experiments) appears proportional to the TS concentration. The pH of the digesters at 10% were adjusted with NaOH several times during the first month. Digesters at 5% or less, the pH remained neutral. Hence, no pH adjustment was required.

ACKNOWLEDGEMENTACKNOWLEDGEMENT

The authors of this project want to thanks theThe authors of this project want to thanks the following contributors:

Torrado’s Dairy Farm for providing the raw y p gmaterial and the knowhow about the day-to-day dairy operationCentro de Investigación y Creación (CIC) for providing the funds for this project.

FOOD FOR THOUGHT…Ref. Thomas Menke, Menke Consulting Inc.