mfc.results 1-10 (1).pptx

‫الرحيم‬ ‫الرحمن‬ ‫هللا‬ ‫بسم‬
)
‫أنت‬ ‫إنك‬ ‫علمتنا‬ ‫ما‬ ‫إال‬ ‫لنا‬ ‫علم‬ ‫ال‬ ‫سبحانك‬ ‫قالوا‬
‫الحكيم‬ ‫العليم‬
(
‫العظيم‬ ‫هللا‬ ‫صدق‬
‫اآلية‬
(
32
)
‫البقرة‬ ‫سورة‬

The Effect of Variable Microorganisms on The Efficiency of
Microbial Fuel Cell
A Thesis
Submitted in partial fulfillment of the requirements for the degree of
Master of Science in Microbiology
To
Botany and Microbiology Department, Faculty of Science, AL-Azhar University, Assuit
By
Mahmoud Sadek Mohamed
Under Supervision Of
Dr. Elsayed khalaf Bakhiet
Assistant prof. of Microbiology, Botany and
Microbiology Department, Faculty of
Science, AL-Azhar University, Assuit.
Prof. Dr. Salah El-Din Gamal
El-Din Badr
Professor of Microbiology, Botany and
Microbiology Department, Faculty of Science,
AL-Azhar University, Assuit.

 Energy considers one of our needs in modern life, Continued use of petroleum fuels
is widely being recognized as unsustainable because of their depleting supplies, That
created a gap between the accelerating demand for energy and on other hand
availability of fossil fuels, which causes the market price to increase. In fact, the
price of crude oil has trebled over the last ten years.
 Worldwide electricity generation is still mainly dependent on fossil resources. Over
67% of the electricity produced is originating from coal, oil or natural gas. Other
sources are nuclear 13.4%, hydropower (16.2%) and others including wind, solar
biofuels and waste 3.3% (International Energy Agency, 2014).
 It is no doubt that using Fossil fuels has a catastrophic impact on the nature such as
global warming and atmospheric pollution because the emission of carbon dioxide
results from consumption of fossil fuels, hence there is considerable interest in
research finding cheap alternative renewable energy.
Energy issues

 Renewable energy is the energy created by sources, which are naturally replenished such
as sunlight, rain, wind, biomass and tides.
 Renewable Energy sources are not depleted, and it is distributed over a wide
geographical area, these resources are quickly renewed through natural process. It won’t
create any environmental pollution problems the main advantage of using renewable
resource is it is available throughout the year.
 Bioenergy is a broad category of energy fuels manufactured from a variety of feedstock
of biological origin and by numerous conversion technologies to generate heat, power,
liquid biofuels and gaseous biofuels.
 Bio-power capacity increased by an estimated 5% in 2015, to 106.4 GW, and generation
rose by 8% to 464 TWh; the rise in the generation was due in part to increased use of
existing capacity
 In this context, microbial fuel cells (MFCs) have emerged as a promising yet challenging
technology.

A microbial fuel cell is a device that converts chemical energy to electrical energy by the
catalytic reaction of microorganisms. ”
“ A microbial fuel cell (MFC) or biological fuel cell is a bio-electrochemical system that
drives a current by mimicking bacterial interactions found in nature. ”
 A MFC often consist of two compartments, the anode and the cathode chambers separated
by a proton exchange membrane (PEM). Microbes in the anode chamber oxidize reduced
substrates and generate electrons and protons in the process.
 After crossing the PEM, the protons enter the cathode chamber where they combine with
oxygen to form water (Figure 2).
 MFC operates at near about ambient temperature & nearly neutral solutions.
 They operate on complex substrate present in wastes.
Principle

Fig (2): A schematic diagram of the Microbial Fuel Cell

 Anode at anaerobic conditions & cathode at aerobic.
 Unlike chemical fuel cells, MFC anodes are ‘bio-electrodes’ consisting of living
microorganisms on conductive solid material.
 In cathode, Oxygen is the most obvious choice of electron acceptor for an MFC due
to its high oxidation potential, availability, low cost (free), sustainability, and the
lack of a chemical waste product (water being the only end product).
 Anodic Reaction ex.
CH3COO + 2H2O -------- ► 2CO2 + 7H+ + 8e –
 Cathodic Reaction ex.
O2 + 4H+ + 4e- -------- ► 2H2O
 IEMs are still widely used in MFC research due to their good performance. The
most commonly used IEMs in MFCs are cation exchange membranes (CEMs)
especially Nafion®.
 For MFC power generation and cost, the choice of suitable electrode materials is
very important, the selected electrode materials should be able to improve
efficiency and reduce cost.
 Exoelectrogenic (ex; E. coli) “exo-“for exocellular and “electrogene” based on the
ability to directly transfer electrons to a chemical or material that is not the
immediate electron acceptor this, bacteria are the most suited to function within an
MFC .

Microbes Substrate Applications
Geobacter metallireducens
Geobacter sulfurreducens
Acetate Mediator-less MFC
Shewanella oneidensis Lactate Mediator-less MFC
Alcaligenes faecalis,
Enterococcus gallinarum,
Pseudomonas aeruginosa
Glucose Self-mediate consortia isolated from MFC
with a maximal level of 4.31 W m− 2.
Pseudomonas aeruginosa Glucose Pyocyanin and phenazine-1-carboxamide as
Mediator MFC
Clostridium butyricum Starch, glucose,
lactate, molasses
Fermentative bacterium
Various Microbes used in MFCs

 Double chambered fuel cells as the name suggests are
composed of two compartments or chambers. Both the
cathode and anode are housed in different compartments
connected via a proton exchange membrane (PEM) or
sometimes PEMs or salt bridges mainly function as a
medium for transfer of protons to make the circuit or
reaction process complete
Designs of MFC
 These MFCs consist of only one compartment - an
anode compartment. They are simple, there is no
definitive cathode compartment and they may or may
not contain a PEM. Porous cathodes form one side of
the wall of the chamber and can utilize oxygen from the
atmosphere allowing protons to diffuse through them.

 Microbial fuel cells which use a mediator to transfer electrons produced from the
microbial metabolism of small chain carbohydrates to the anode (Logan et al., 2006).
This is necessary because most bacteria cannot transfer electrons directly to the anode
(Scholz et al, 2003). Mediators like thionine, methyl blue, methyl viologen and humic
acid tap into the electron transport chain and abstract electrons (becoming reduced in
the process) and carry these electrons through the lipid membrane and the outer cell
membrane.
 Mediator-free microbial fuel cells do not require a mediator but use electrochemically
active bacteria to transfer electrons to the electrode (electrons are carried directly from
the bacterial respiratory enzyme to the electrode). Among the electrochemically active
bacteria are, Shewanella putrefaciens, Aeromonas hydrophila, and others.
Types of MFC

Types of MFC
 Energy can be harvested from organic matter in aquatic
sediments .They consist of an anode embedded in anoxic
sediments connected to a cathode suspended in the overlying
aerobic water (Lovley, 2006). In these systems no addition
of organic matter is necessary and complex organic matter
from the sediments is broken down by hydrolytic and
fermentative microorganisms to acetate and other electron
donors.
 The Plant-Microbial Fuel Cell (P-MFC) uses living plants
and bacteria to generate electricity. It makes use of
naturally occurring processes around the roots of plants to
directly generate electricity. This organic matter can be
oxidized by bacteria living at and around the roots,
releasing CO2, protons and electrons. Electrons are
donated by the bacteria to the anode of a microbial fuel
cell.
The Plant-Microbial Fuel Cell
The Sediment Microbial Fuel Cell

 MFCs could be installed to wastewater treatment plants. The bacteria would consume waste
material from the water and produce supplementary power for the plant.
 Chemical energy of Organic compounds converted into electricity rather than heat. Hence
higher conversion energy comparable to chemicals cells is achieved.
 Higher electron recovery again as electricity of up to 89% was also reported (Rabaey, et al.,
2003) .
 In an MEC, an external voltage must be applied to overcome the thermodynamic barrier,
Protons and electrons produced at the anode are combined at the cathode to form Hydrogen.
 The hydrogen can be accumulated and stored for later use to overcome inherent low power
feature of MFCs.
Applications of MFC

Applications of MFC
 Municipal wastewater, Sanitary waste, Organic waste from farms or industry has
multitude of organic compounds that fuel MFCs.
 MFCs can enhance the growth of bio electrochemically active microbes during
wastewater treatment thus they have good operational stabilities.
 COD up to 80% can be removed and has a high columbic efficiency of 80%.
 Since the current generated from a microbial fuel cell is directly proportional to
the strength of wastewater used as the fuel, an MFC can be used to measure the
strength of wastewater.
 MFCs can be up to 90% efficient in power production compared to 50% for
typical fossil fuel power plants.

Applications of MFC
 MFCs can run low-power sensors that collect data from remote areas. A simple
microbial fuel cell consisting of a cathode attached to an anode by a metal wire.
 Microbial Fuel Cell-type biosensor can be used to measure real time BOD values
 One major advantage of using a microbial fuel cell in remote sensing rather than a
traditional battery is that the bacteria reproduce, giving the MFC a significantly
longer lifetime than traditional batteries.
 Microbial fuel cell technology can be modified to desalinate marine water.
 This can be done by placing a third chamber between the anodic and cathodic
chambers, separating the third chamber from the other two with ion-specific
membranes that allow for the passage of either positive ions or negative ions but
not the both of them in one direction.

1. Efficient and direct conversion of organic substrate to electricity.
2. Unlike conventional cells MFC could operate well in mild conditions,
20°C to 40°C and also at pH of around 7.
3. Can be installed in locations lacking electrical infrastructures.
4. Alternative to present source of fuel to meet energy needs.
5. The gains to be made are that MFCs are a very clean and efficient
method of energy production and they also treat waste generated in
daily life so use of MFCs are like “Hitting two birds with one stone”.
Advantages of MFC

1. Limit on surface area of anode as bacteria can clog small pores and
hence limit on current.
2. Still not economically competitive.
3. Power produced way below when compared with conventional cells.
4. The practical value of maximum voltage achieved is very low when
compared to the theoretical value
5. This can be attributed to
1. Activation losses.
2. Bacterial metabolic losses.
3. Concentration losses.
Limitations of MFCs

1. Substrate,
2. Microorganisms and their metabolism, electron transfer mechanism
in an anodic chamber
3. Electrodes material and the shape of electrodes,
4. Type of membrane,
5. Operating conditions such as temperature, pH and salinity,
6. Electron acceptor in a cathodic chamber
7. Geometric design of the MFC

Enlarging reactor size
 When the MFC is scaled up to several liters or more, the volumetric power density
can be 2–4 orders of magnitude lower than that of laboratory-scale MFCs.
 The solution resistance and pH gradient and inhomogeneity affect on the efficiency
of large-sized MFCs.
MFC stacks
 May be a more feasible option for MFC scaling-up.
 is to construct stacks of moderately-scaled MFC units. To practically apply MFCs
as an energy source, one can connect MFC units in parallel to produce a higher
current or in series for a higher voltage.
Scaling up MFCs

This thesis sets out to fulfill the following objectives:
1- Assessment of novel MFC design for generating electricity from waste.
2- To observe and find the characteristics of maximum generated power
for anode solution.
for cathode solution.
for different electrode type and surface area.
5- Analysis of anodic biofilms on MFC electrodes.
for different microorganisms.
7-Assessment of Up Scale MFCs.
7- Assessment of novel MFC efficiency for generating electricity by COD,
Columbic efficiency, Polarization curve, power cost ratio(PCR)

.1 Collection of substrate samples
Five samples of different substrate were collected from different localities at
Sohag Governorate .
[Cow dung – diluted Wheat straw hydrolystate – Nile sediment – Wastewater –
Human urine],
Samples were collected during the period from April 2016 (summer) to January
2017(winter).
Chemical & Physical properties of theses substrate samples were measured. such as:
2.1 COD Measurement
2.2 Measurement of total organic carbon TOC
2.2 Measurement of total nitrogen TN
2.4 pH measurement
2. Determination of chemical parameters for samples

.3Microbial Fuel Cells (MFCs) Design
Comparison of electricity production while varying experimental parameters like substrate,
microbes, electrode, cathode for improving electricity generation.
3.1. Separator
Type I: MFCs with salt bridge cell (H shape).
Type II: MFCs with clay pot membrane less system two chambers from plastic separated
by separator from clay pot
3.1.1 Effect of difference between two types of separators
Type I Type II

Anode chamber
1-50 ml of L.B media
2-50 ml of 100 mM phosphate buffer (pH 7.0)
3 - 2 ml of E.coli suspension
Anodic chamber was sealed completely by double sheet of aluminum foil for the growth of
facultative anaerobic conditions.
Cathode chamber
50 ml of phosphate buffer
50 ml of 50 mM K4Fe (CN) 3
Make pores in upper side of chamber for aerobic condition
Electrode
Electrode material which used in each cathode and anode chamber contain one copper electrode
as rod form with diameter 0.13 × 6.37 cm.

Salt Bridge at type I
The PVC pipe used in salt bridge construction had dimensions of 5 cm length and 1cm diameter.
Volume 3.9 cm3 was calculated using the formula r2h. Salt bridge was prepared using 20 ml of 1
M KCl solution and 5 % agar. The solution was first subjected to heat for blending, which in
return gave a clear solution of agar and KCl
Clay pot sheet at typeII
We used customs made cylinder clay pot-all cylinder or sheet of it was sterilized by immersed in
5 % hypochlorite bleaching solution then washed by 70 % ethyl alcohol before used.
Microbe
A pure culture of E.coli was used as the inoculum in the anode compartment of the MFC, was
developed by growing on LB broth medium .
MFC Operation
*The MFC operated at room temperature ( 30 +/- 5C (.
*The generated voltage was recorded from the desktop multimeter for 7 day.
* The voltage (V) across an external resistor (100Ω( in the MFC circuit was continuously
recorded at the intervals of 24 h for all the cells.

3.1.2 Effects of designs of clay pots sheet
Type III Type II
3.1.3 Effects of different thickness of clay pots as anode chamber
1- Pottery clay pot with thickness (3.0 mm) as water colder.
2- Pottery clay pot with thickness (5.0 mm) as drink birds.
3- Pottery clay pot with thickness (5.0 mm) as food container coating with pigment.
4- Pottery clay pot with thickness (10.0 mm) as a piggy bank.

3.2. ANODE
3.2.1 Effect of different Substrate types
The purpose of the present study was to evaluate the availability of the different five types of
substrate as fuel for an anode MFC as: [Cow dung – diluted Wheat straw hydrolystate – Nile
sediment – Wastewater – Human urine] to generate electricity in double chamber microbial
fuel cell system.
3.2.2 Effect of different volumes of wastewater in anode chamber
Trials: In the first trial, 150 ml of wastewater was added.
During second trial, 200 ml of wastewater was added.
In third trial, 250 ml of wastewater was added.
In fourth trial, 300 ml of wastewater was added.

3.2.3 Effect of long period on electric power of MFCs
3.2.3.1 Wheat Straw
In this trial, anode chamber contains 50 g of Wheat Straw in 250 ml dist. water.
3.2.3.2 Wastewater
During second trial, anode chamber containing 250 ml wastewater.

3.2.5 Effect of substrate feed batch each 3 day on power generation
In batch MFC: take 100 ml from anode by sterilized syringe and add 100 ml from new
wastewater to anode each 3 days for 15 days.
In control MFC: no addition during the experiment.
3.2.6 Effect of different between summer and winter waste samples
Setup two MFC cells using of wastewater as hot and cold Samples in the anode chamber.
3.2.7 Effect of mixed wastes in anode chamber
In the first trial, 100 g of Wheat Straw in 250 ml of Human Urine.
During the second trial, 100 g of Cow Dung in 250 ml Human Urine.

3.3.CATHODE
3.3.1 Bio Cathode
Each Cathode and Anode chamber contains 250 ml of substrate as:
1. Human urine
2. Wheat Straw
3. Cow dung
4. Wastewater
3.3.2 Aquatic Cathode
Cathode chamber for all cells contains250 ml dist. water only but Anode chamber contains 250
ml of substrate as:
1. Human urine
2. Wheat Straw
3. Cow dung
4. Wastewater

3.4. ELECTRODE
3.4.1 Effect of electrode materials
We use two types of electrodes [carbon- copper]
In first cell Anode and cathode contain Carbon electrode with Surface Area: 15.0 cm2.
In second cell Anode and cathode contain Copper electrode with Surface Area: 5.3 cm2.
1. Wheat Straw
2. Cow dung
3. Human Urine
4. Wastewater

3.5. MICROBES
3.5.1 Isolation and identification viable microorganisms from anode electrode surface
3.5.1.1. Strains Isolation
3.5.1.2 Identification and characterization of micro-organisms
3.5.1.2.1. Colony Morphology
The size and morphology of the bacterial colonies was determined by the help of an ocular and
stage microscope.
3.5.1.2.2. Gram staining
Smear of the colonies was made on slides and Gram staining techniques were carried out.
3.5.1.2.3. Biochemical detection tests
Various biochemical tests had done on two isolates which had given high voltage to identify the
bacteria like starch test, Methyl Red test, citrate test, Urease test, by using Bergey's Manual of
Determinative Bacteriology.

3.5.1.2.4. SEM Analysis
The images were captured using scanning electron microscope (SEM) (Hitachi) JEOL JMS
5300 scanning electron microscope at magnifications of 7500 using an electron beam high
voltage of 30 kV.
3.5.2 Assay isolated cultures bacteria used in MFCs
A pure cultures of [Isolate 1, 2, 3, 4, 5,] were isolated and identification at experiments 3.5.1
used as inoculum in the anode compartment of the MFC
3.5.3 Assay pure and mixed identified cultures bacteria used in MFCs
Pure cultures of [Escherichia coli– Bacillus subtilis- Staphylococcus aureus] were used as
inoculum in the anode compartment of the MFC.

4. Up Scale Experiment
we designed two Types of up scale MFCs as:
1- Large Size MFC (1L of waste)
Large dual chambered MFC and filled up by 1.0 L wastewater as substrate .while cathode
filled up 1.0 L tap water.
2- Stack MFCs (250 ml waste × 4 combined cell)
Four MFCs Connecting successively in two series each cell contain small dual chambered
5.Some Analyses and calculations
5.1. Polarization curve & power curve
The polarization and power density curves were obtained by operating the cells at different
external circuit resistances (100 –10000 Ω( after the addition of fresh wastewater a steady state
of operation.

5.2. COD Removal Efficiency
According to this equation we can detect the efficiency of MFC to remove chemical oxygen
demand COD for upscale MFC.
COD removal efficiency = COD inlet - COD outlet × 100
COD inlet
5.3. The Columbic Efficiency (CE)
The Columbic efficiency, defined as the ratio of total charge actually transferred to the anode
from the substrate to the maximum charge if all the substrate removal produced current.
5.4. Power to cost ratio (PCR)
According to Ashutosh Patra (2008), method Power to cost ratio (PCR) metric was used to
compare the low-cost MFCs to more costly MFCs that produce higher amounts of power.
Power (mW) = voltage (V) × current (mA)
Assuming power output is proportional to anode surface area, then:
Surface power density (mW/m2) = Power (mW) ×10 000 / surface area (cm2)
Power to cost ratio (PCR) = surface power density (mW/m2) / Cost ($)
CE = 8 ∫0
tb
𝑖𝑑𝑡
𝐹𝑉an Δ𝐶𝑂𝐷

Determination of Physiochemical parameters for samples
These measurements shown that waste water the value high COD value as 980 mg/l
While, diluted wheat straw had low value as 510 mg/l , In other hand there was not high
variation between pH values for different samples which given high at diluted Nile
Sediment as 7.3 while the low value at cow dung as 6.6.
parameters wastewater cow dung urine Nile sediments wheat straw
pH 6.9 6.6 7.0 7.3 6.8
COD mg/L 980 720 627 578 510
TOC mg/L 1014.6 973.9 889.3 912.6 725.2
Total N mg/L 58 41 67 35 46
Table 1: waste parameters

1.1. Effects of different types of separators
Figure1:Difference between MFC designs Type I and Type II
246
147

1.2. Effects of different designs of clay pots sheet as separator
Figure 2:Difference between MFC designs Type II and Type III
334
246

1.3. Effects of different types of clay pots as anode chamber
Figure.3: Effect of Clay Pots Thickness on production of electricity in Type III MFCs.
124
351
151
302

2- ANODE
2.1. Effect of different substrate types
Figure.4: Effect of different Substrate types on production of electricity in Type III MFCs.
351
421
336
414
478

2.2. Effect of different volumes of wastewater in anode chamber
Figure.5: Effect of different Substrate Concentrations on production of electricity in Type III MFCs.
292
151
302
124

2.3. Effect of long period on electric power of MFCs
Figure.6: Effect of Long period on production of electricity in Type III MFCs.
472
218

2.5. Effect of substrate batches on power generation each 3 day
Figure.8: Effect of substrate Flow Rates each 3 day on production of electricity
524
418
313
347

2.6. Effect of difference between summer and winter wastewater samples
Figure.9: Effect of summer and winter season on production of electricity

2.7. Effect of mixed wastes in anode chamber
Figure.10: Effect of Mixed different Substrate Concentrations on production of electricity
638
384

3- CATHODE
Bio Cathode and Aquatic Cathode
Figure.11: Effect of difference between maximum voltage in Aquatic and Bio cathode on production of electricity

4-ELECTRODE
4.1. Effect of electrode materials
Figure.12:Effect of difference between Copper and carbon electrode on Maximum voltage

4.2. Effect of surface area of electrode in Anode chambers
Figure.13: Effect of different Copper electrode surface Area in anode chamber on production of electricity
354
317

4.3. Effect of surface area of electrode in cathode chambers.
Figure.14: Effect of different Copper electrode surface Area in cathode chamber on production of electricity
380
318

5- MICROBES
5.1.1. Sample isolation
The Five bacterial isolates were designated as ISO 1, ISO 2, ISO 3, ISO 4, ISO 5
Figure15: Colony
morphology of five isolates

5.1.2. Identification and characterization of organism
5.1.2.1. Colony Morphology
The size and morphology of the bacterial colonies was determined by the help of an ocular and stage
ISOLATE NO. Form color Surface margins elevation
ISO 1 irregular translucent smooth entire convex
ISO 2 circular white smooth entire raise
ISO 3 circular yellow smooth entire flat
ISO 4 circular white smooth entire flat
ISO 5 circular orange smooth entire flat
Table 2: Colony morphology of five isolated strains from electrode of anode chamber Type III MFCs.

Isolate No. Shape Gram stain
ISO 1 Rod Gram negative
ISO 2 Cocco bacill Gram negative
ISO 3 Cocci Gram positive
ISO 4 Rod Gram negative
ISO 5 Cocci Gram positive
5.1.2.2. Gram staining
Smear of the 5 colonies were made on slides and gram staining techniques was carried out and
the results were obtained as shown in table 3
Table 3: Gram Stain of five isolates

Test W 1 W 3
Catalase - -
Methyl red - +
Indole - +
Citrate + -
Nitrate + -
starch + -
Oxidase - +
5.1.2.3.Biochemical detection tests:-
Various biochemical tests to identify the most potent strains for electricity generation like starch
test, Methyl Red test, citrate test, Urease test as Based on colony Morphology the staining and the
biochemical test the bacterial isolates were identified (Table 4 ).
Table 4: Biochemical tests of two high potential isolates

5.1.2.4. SEM Analysis
a b
c d
Figure16: SEM images of electrode surface before and after using in Type III MFCs

ISOLATE NO. SPECIES
W 1 Enterobacter sp.
W 3 Streptococcus sp
The present work showed that the five bacterial species, Enterobacter sp and Streptococcus
sp. were separated from anode surface of MFC after experiment detected after isolation and
purification on nutrient agar and MacConky agar and Gram stain then some biochemical
tests after it had given high voltage.
Table 5: identification of high potential two isolate

5.2. Assay isolated cultures bacteria used in MFCs
Figure.17 Maximum voltage for different five isolates from Type III MFCs.
179
184

5.3. Assay pure cultures bacteria used in MFCs
Figure.18 Effect of different pure Bacterial Strain in anode chamber on production of electricity
121
100
146
274

Part II: up Scale Experiment
Figure.19 Effect of different up Scale MFC designs on production of electricity

Analyses and calculations
1-Polarization curve
Figure.21 Stack MFCs polarization power curve
Figure.20 large MFC polarization power curve

2-COD Removal Efficiency
For large scale Type III MFCs
The initial COD value recorded before the MFC process for the activated
Wastewater was 980 mg/l, and the final COD after the MFC process was 330
mg/l .Based on the COD removal after the MFC process, the carbon removal
efficiency was demonstrated by the wastewater , which had a value of 66.3%.
For Stack Type III MFCs
The initial COD value recorded before the MFC process for the activated
Wastewater was 980 mg/l, and the final COD after the MFC process was 240 mg/l
Based on the COD removal after the MFC process, the carbon removal efficiency
was demonstrated by the wastewater, which had a value of 75.5 %.

3-The Columbic Efficiency
large scale Type III Mfc
I = 0.000270 A
tb=7 days, F= 96,500 C/mol.
Van= 1000 mL = 0.0010 m3
COD=980 mg/L - 330 mg/L= 650 mg = 0.650 g/L
tb= 7 days = 7 x 24 x 3600 seconds
CE = 20.89 % for large scale Type III Mfc
Stack Type III MFCs
I = 0.000058 A
tb=7 days, F= 96,500 C/mol.
Van= 1000 mL = 0.0010 m3
COD=980 mg/L - 240 mg/L= 740 mg = 0.740 g/L
tb= 7 days = 7 x 24 x 3600 seconds
CE = 30.66% for Stack Type III MFCs

4-Power to cost ratio (PCR)
Component Units Value($) Value(ᵽ)
Clay Pot ( Small ) $ / piece 0.75 11
Plastic Box $ / piece 1.0 15
Copper electrode $ / 100 cm2 0.50 7.5
Aluminum Foil $ / 100 cm2 1.0 15
Copper wire $ / 100 cm 0.25 4
Total cost for MFC $ / m2 of anode 3.5 52.5
Table 6. Cost of Type III MFCs
• Final power to cost ratio of our MFC by $ = 21.64 mW / 3.5 $ = 6.18 mW/$
• While Ashutosh Patra design MFC had PCR = 0.42 mW/$
• Final power to cost ratio of our MFC by P = 21.64 mW / 52.5 P = 0.41 mW/P
• Final power to cost ratio of our large MFC by $ = 40.6 mW / 5.0 $ = 8.12
• Final power to cost ratio of our stack MFC by $ = 4.06 mW / 5.0 $ = 8.6 mW/$
• The experiments demonstrated the ability to construct low-cost, effective MFCs. For
example, Design Type III was 15 times as cost efficient ($/mW) as the typical Ashutosh
Patra MFC design

Conclusion
This works analyses the role of several designs locally available factors in MFC performance.
Our efforts were being made to improve the system performance, construction and operation cost.
1-In this study the five types of waste ( Wastewater -wheat straw -cow dung- human urine- Nile
Sediment )
we selected type III as best model by compared to Type I and Type II which had given high
voltage where type III has increasing in voltage by 244 % and 36% from type I and type II
respectively.
2-The results not shown too much variation but up stand these results we depended on
wastewater in next experiments as the substrate where the output of the voltage was
maximum.478 mV whereas in the case of cow dung as a substrate it was found to be 469 mV and
wheat straw maximum voltage. 421 mV and maximum voltage in the case of Nile sediment was
351 mV, human urine was found to be 336 mV.
3-limiting factors for anode chamber like the volume that we took the volume in anode chamber
as 250 ml of substrate and period as we took a 7 days after 31days of observation which had
given high output as 478 mv .

4-Mixed substrate in anode chamber would enhance giving high potential than single substrate for example
voltage generated at media Wheat Straw + Urine was 638 mV.
5-we noted that the summer season samples better than the winter season samples because voltage generated
at winter season was 302 mV while voltage generated at summer season was 478 mV.
6- in cathode chamber we saw that using water in cathode (aqua cathode) had given best output potential
than using waste of same material in cathode (biocathode) .
7-From this study, copper electrode was selected as the most efficient and consistent electrode than carbon
electrode although the carbon electrode has total surface area 15.0 cm2 and the copper electrode 5.3 cm2.
8-The increasing in surface area of electrode would have a little effect on output potential where the voltage
increased by 5 % and 17 % when we duplicated surface area from 5.3cm2 to 10.6 cm2 and 15.9 cm2
respectively in anode chamber 5 % and 25 % respectively at duplicated in cathode chamber .
9-The nutrient agar medium was used for isolation of bacteria from waste water with dilution 10-5.had given
five bacterial isolates.
We can see from these results that isolates 1 & 3 had given relative high voltage , the isolate 1 had given
179 mv and isolate 3 gave 184 mV at that were Enterobacter sp.and Streptococcus sp. were separated from
anode surface of MFC after experiment.

10-using a pure identified stains such E.coli had given power by 121 mV, Bacillus sp had given
power by 146 mV while Staphylococcus aureus had given power by 100 mV and mixed E.coli
and Staphylococcus aureus have given power by 274 mV.
11-the second goal was upscale and optimization MFC power. we made two ways one by enlarge
single MFC where Large Size MFC has given maximum voltage by 717 mV the other way that
connected 4 a small MFC in in series way, as we did which had given high voltage but low power
due to with connection in series where the voltage increase to1081 mV by 248%,
12-Some analysis did on upscale MFC like Polarization power curve when the polarization
curves and we found that the internal resistance of cell at 700 Ω for large MFCs and stack MFCs
.The Columbic efficiency was 20.9 for large MFC and 30.7 for stack MFCs. the COD the
carbon removal efficiency was demonstrated by the wastewater , which had a value of 66% it was
980 mg/L, and the final COD after the MFC process was 330 mg/L for large MFCs and 75.5 foe
stack MFCs.
13-According to Ashutosh Patra method power to cost ratio (PCR) these experiments
demonstrated the ability to construct low-cost, effective MFCs. For example, While Ashutosh
Patra design MFC had PCR 0.42 mW/$ Power to cost ratio (PCR) for our small MFC was 6.18
mW/$ by Type III it was near to 15 times as cost efficient ($/mW) as the typical Ashutosh Patra
MFC design.

mfc.results 1-10 (1).pptx

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mfc.results 1-10 (1).pptx