G R O U P :

LU I S A M A R O

I S T VA N LÓ P EZ

V I C TOR S E R R A NO

M A N U EL F O NTÁ N

Research Purpose:

Find alternative solutions or remedies for producing clean energy from poultry waste

Through data, we will evaluate if there is any possibility to use bio-gas as an economic fuel

Analyze its composition and properties

Describe and illustrate the process for producing bio-gas

Provide an example involving the Carnot Cycle (an ideal cycle with zero irreversibility)

Provide a study for public health

General analysis of producing energy through bio-gas

Benefits of using poultry waste as fuel:

Properly convert waste into eco-friendly energy which will improve economical issues

Improve general community well being

Prevents the propagation of diseases, mosquitoes, flies, and other pests

Low cost for machinery maintenance because of its simple process

During anaerobic digestion, organic nitrogen is converted into a more-valuable fertilizer, ammonium

Independent of rising fuel costs, it is a predictable and, almost, constant energy production and costs

Beneficial process because it improves various aspects of society

Bio-gas Composition:

Gas Properties Composition Porcentage Molecular Weight

Methane (CH4) 60% 16.04 lb/lbmol

Carbon Dioxide (CO2) 35% 44.01 lb/lbmol

Hydrogen Sulfide (H2S) 1.67% 34.08 lb/lbmol

Ammonia (NH3) 1.67% 17.03 lb/lbmol

Water Vapor (H20) 1.67& 18.02 lb/lbmol

Bio-gas is composed of various compounds (mostly methane gas)

What is methane gas?

Methane gas (CH4) is a chemical compound that is a principal component of natural gas due to

its simplest alkane

Most potent greenhouse gas with over 20 times the heat-retaining capacity as CO2.

Burns easily and produces a hot flame

Odorless, harmless, and tasteless

Good source to use as a fuel

A chemical compound highly useful for combustion

Precautions and Cons of process:

Requires expertise and skills for anaerobic digesters

Manure and digestive system must be compatible

Requires much waste for it to be feasible

Methane can be dangerous if mixed with air

Methane leaks are difficult to detect because it is odorless, colorless, and it’s not visible

Requires additional work and precautions

How methane gas is produced naturally?

Production of methane is a natural occurring process

What is a digester:

They are typically constructed from concrete or steel

Most digesters require 20-30 days for the bacteria to convert the organic wastes into acids and then methane gas

The bacteria in a digester are very sensitive, requiring a pH of 7 and a consistent temperature near 35o C

Some use a cogeneration in which heat is added to accelerate the process

Digester is the principal and one of the most important component of the process

Process for decomposition of the bio-gas

Problem Proposed:

Engineering Process:

Carnot Cycle

Engineering Process Continued: Defining the system

Dividing the Cycle into 4 processes

-Process 1-2

-Process 2-3

-Process 3-4

-Process 4-1

Applying Energy Balance Equation (First Law of Thermodynamics) to obtain heat transfer and work in each process

Total work for the cycle will be obtained by the summation of each work in each process

Process 1-2:P = 10 Bar

T = 179°C = 452K Process is Isobaric and Isothermal

m = 25kg of 𝐻2𝑂 It goes from saturated liquid to saturated vapor

ν 1=1.1273x10−3𝑚3

𝑘𝑔𝑢1=761.81

𝐾𝐽

𝑘𝑔ℎ1=762.81

𝐾𝐽

𝑘𝑔

ν 2=0.1944𝑚3

𝑘𝑔𝑢2=2,583

𝐾𝐽

𝑘𝑔ℎ2=2,778.1

𝐾𝐽

𝑘𝑔

𝑊1−2 = 12𝑑𝑣 = 𝑝 𝑣2 − 𝑣1 = 10𝑥105

𝑁

𝑚2 0.1932727𝑚

𝑘𝑔= 193.2727

𝐾𝐽

𝑘𝑔

𝑄1−2 = 𝑚 ℎ2 − ℎ1 = 50,382.25𝐾𝐽

Process 2-3:Steady State→ = 𝑄𝑐𝑣 − 𝑊𝑐𝑣 + 𝑚𝑖 ℎ𝑖 − 𝑚𝑒(ℎ𝑒) 𝑥3 = 90%

Adiabatic

𝑃3 = 1 Bar 𝑇𝑠𝑎𝑡 = 99.63°∁

𝑄𝑐𝑣 = 0

𝑊𝑐𝑣 = 𝑚 328.404𝐾𝐽

𝑘𝑔 𝑚 = 1

𝑘𝑔

𝑠

𝑊𝑐𝑣 = 328.404𝑘𝐽

𝑠

Process 3-4:𝑄3−4 =

𝑇𝑐

𝑇𝐻𝑄2−1 𝑄2−1=2,015.2900

𝐾𝐽

𝑘𝑔𝑇𝐻 = 453𝐾 𝑇𝐶 = 373𝐾 P=1Bar

𝑄3−4 =𝑇𝐶

𝑇𝐻−2,015.29

𝐾𝐽

𝑘𝑔)= −1,659.3889

𝐾𝐽

𝑘𝑔

ℎ4 = ℎ3 + 𝑄3−4

ℎ4 = 790.3071𝐾𝐽

𝑘𝑔

Process 4-1:Q = 0

𝑣4 = 0.2369𝑚3

𝑘𝑔𝑢4 = 708.3215

𝐾𝐽

𝑘𝑔

𝑣1 = 1.1273𝑥10−3𝑚3

𝑘𝑔𝑢1 = 761.68

𝐾𝐽

𝑘𝑔

𝑊4−1 = 𝑢4 − 𝑢1

𝑊4−1 = −53.36𝐾𝐽

𝑘𝑔

Efficiency:η =

𝑊𝑐𝑦𝑐𝑙𝑒

𝑄𝐻 𝑊𝑝𝑟𝑜𝑐𝑒𝑠𝑠 = 𝑊1−2 +𝑊2−3 +𝑊3−4 +𝑊4−1=339.5367

𝐾𝐽

𝑘𝑔

η =339.5367𝐾𝐽/𝑘𝑔

2,015.29𝐾𝐽/𝑘𝑔= 0.1684

η = 16.85%

η𝑚𝑎𝑥 = 1 −𝑇𝐶

𝑇𝐻= 0.1766

η𝑚𝑎𝑥 = 17.66%

The process is possible

Exergy Analysis:

𝑃0 = 1𝐵𝑎𝑟

𝑇0 = 7℃ = 280𝐾

𝑑𝐴𝑐𝑣

𝑑𝑡= 2.5104

𝐾𝐽

𝑘𝑔

Change in availability is positive

Public Health Impact:Methane is not toxic; however, it is extremely flammable and may form explosive mixtures with air

Breathing in methane at high concentrations, resulting in oxygen deficiency, are increased breathing and pulse rates, lack of muscular coordination, emotional upset, nausea and vomiting, loss of consciousness, respiratory collapse and death

Hydrogen sulfide is a highly toxic and flammable gas that cause eye irritation, a sore throat and cough, nausea, shortness of breath, and fluid in the lungs (pulmonary edema). Also, may result in fatigue, loss of appetite, headaches, irritability, poor memory, and dizziness, or immediate collapse, with a high probability of death

Ammonia is irritating and corrosive that may cause burning of the nose, throat and respiratory tract, if breathed. Also,

High concentration of carbon dioxide may result in nausea and vomiting, collapse, convulsions, coma and death can occur

Effects for improper handling of this process

Public Health Impact Continued:

Provides a renewable source of energy

Leads to improvement in the environment, and better sanitation and hygiene

Lower the greenhouse effects on the earth’s atmosphere

Produces enriched organic manure, which can supplement or even replace chemical fertilizers

Anaerobic digestion inactivates pathogens and parasites

Pros that makes the process feasible

Economical benefits: The digester produces a richer fertilizer with 3 times more nitrogen than a conventional product. Also it is natural and free from harmful synthetic chemicals

Biogas is fully capable of replacing other rural energy sources like wood, hard coal, kerosene, plant residues, and propane

Biogas can be used for cooking, lighting, space heating, water heating, grain drying, gas-fired refrigeration or air conditioning

The technology is cheaper and much simpler than those for other bio-fuels, and it is ideal for small scale application

Leads to employment generation in the rural areas

This method will sustain basic energy needs. Initial period will yield losses, but has potential to obtain long-term profit

Real Example:

Real Example Continued:

Annual-total investment of $23,911 and annual savings of $14,300, giving an annual loss of $9,600 in first year

Approximated Example:

· Fresh Manure @ 25% Solids = 1,620 gallons per day

· Dilution Water Required for 8% Solids = 3,440 gallons per day

· Total Waste Volume Generated = 5,060 gallons per day

· Digester Detention Time = 22.5 days

· Digester Tank Capacity = 22.5 x 5060 = 113,850 gallons

50,000 - BIRD LAYER OPERATION

Round tank: 27 ft (diameter) x 26.5 ft (tall)

References:

http://www.greencarcongress.com/2010/02/biogas-climate-benefit-greater-than-previously-thoughtlund-20100219.html

http://www.bae.ncsu.edu/programs/extension/publicat/wqwm/ebae071_80.html

http://hyperphysics.phyastr.gsu.edu/hbase/thermo/carnot.html

Questions?