Present Analysis on CO2 , Carbon Capture And Moving from Sequestration to Utilization of CO2

Ankit Mathanker Shikha ChoubeyB.Tech 4th SemesterDept. of Chemical Engineering

Project MentorDr. D. Krishna Sandilya

CO2 Emission

Sequestration

Utilization

CO2 Capture

From where Humanity CO2 comes and goes

Present statistics of CO2 in atmosphere

300

320

340

360

380

400

420

440

Conc. Of CO2

Conc. Of CO2 (ppm)

Conc. of CO2 in ppmFeb 2013- 396.78 Feb 2014- 398.91Feb 2015- 401.26

• Average annual increase is 2.112ppm/y in

(2005-2014).• While it is

1.859ppm/y in (1995-2004).

Utilization

Carbon Saver TechnologyHow• Natural gas is treated in low energy cold

plasma with fast rotating arc at very short contact times.

CH4 + e- C + 2H2 + Decarbonized N.G

Why• Removed solid carbon is a high valued product

same as carbon black.• Today world carbon black production is based

on Oil and highly CO2 emissive could be replaced by a cleaner fuel.

• Cost of Carbon Black 700-1200$/t.

Side benefits of technology

• For 1 ton carbon removed, 3.7 tons of CO2 emission prevented.

• Production of 1 ton of carbon black results in 2.5-5 metric tons of CO2.

• Finally reduction of carbon footprint and energy efficiency.

Utilization : Microalgae for sustainable energy technology

Energy Technology• Biodiesel is a renewable fuel currently derived

from vegetable oil and animal fats.• One such source is microalgae.• Microalgae are sunlight driven cells factories

that converts CO2 to potential biofuels and other high value bio-active compounds.

Amount of Oil by different feedstockFeed Oil(Lit/Hectare)Castor 1413Palm 5950Coconut 2689Soya/Sunflower <1000Algae 1,00,000

Why Microalgae

Algae Production and facts• Growth depends on

i. pH control ii. Temperatureiii. Sunlight

Utilizationiv. Fluid Mechanics

• Algae will grow in most water sources varying pH levels.

• Growth of algae 10 to 50 gm/m2day.

• Algae is capable to fix (1.8 kg of CO2 for 1kg algae).

• Oil content (Oil per weight of dry biomass) ranges from 20 to 50% depending on species.

“Literary Review: 40 Hectare algae ponds fixes CO2 from 1MW power plant at 50% capture efficiency”.

Organization for algae product done by:

Parameter Open Raceway pond

Closed photo bioreactors

Scale Large & Pilot Scale Laboratory ScaleCost Cheaper to construct More expensiveUsage Commercial Not CommercialTypical cost of biodiesel

2.0-2.5 USD/L 5-6 USD/L

Light Utilization Poor Very HighCO2 loses to atmosphere

High Almost none

Typical biomass yield (g/m2.day)

10-60 60-100

Area requirement Large Small

Fossil Fuel

Stationary combustion

system Pre Process CO2 Removal

Post Process

Pre Process

Algae Cultivation

Algae Harvesting &

Drying

Lipid Extraction

Extracted Lipid

• Commercial Products( Biodiesel, Glycerol)• Fixed Carbon for sequestration

Power

Coming to Carbon CaptureMethods of Capturing CO2

• Pre-combustion: Pre-combustion is mainly applicable to IGCC (integrated gasification combined cycle) where solid fuel is converted into gaseous components called syngas by applying heat under pressure of steam and oxygen.

• Post combustion: In post combustion carbon capture CO2 from combustion flue gases prior to discharge to the atmosphere and this process is applicable to PC (Pulverized Coal) power plants.

• Oxy-combustion: In oxy-combustion capture process uses high purity oxygen instead of air, for fuel combustion to produce highly concentrated CO2.

Advantages and Dis-advantages of various Carbon Capture Processes

Membrane SeparationUses permeable or semi-permeable materials that allow for the selective transport and separation of CO2 from flue gas.

Quality or Membrane selectivity

• Ratio of permeate flow to feed flow.

• Ratio of permeate pressure to feed pressure.

Advantage

• Simple, passive operation with no moving parts.

• Immunity to chemical contaminants since no reactions occurs.

• Energy efficiency with low operation costs.

• Small footprints that is easily expandable due to modular nature.

Disadvantage

Multiple stage membrane separation is required leading to :• Increase complexity.• Energy consumption.• Capital cost.

Challenges

Generally viewed positively for high-pressure application but not as promisingly for low combustion flue gas.

Absorption

Physical Absorption

(Based on Henry’s Law)

Absorbents: Ionic liquids,

Alkanolamines & BlendsConcern:• CO2 capture efficiency• Absorption rate• Energy required in regeneration• Volume of absorber• CO2 is absorbed under

high pressure & low temperature.

• Desorbed at high temperature & low pressure

Existing commercial process

Selexol Process Rectisol ProcessAbsorbents: Dimethyl ether, Propylene glycol• For both CO2, H2S

removal• Low temperature

operation• Regeneration:

Decreasing pressure, or stripping.

Absorbents: Methanol• Favourable when

dealing with exhausted gas contains sulphur.

Advantage: • Low vapor pressure• Low toxicity• Less corrosive

solvent

Advantage:• Less corrosive• More absorbent

Chemical AbsorptionComponents: Absorber, Stripper

Process• CO2 enter packed bed absorber from

bottom.• Contacts counter-current with a CO2

lean absorbent• CO2 rich absorbent flow in stripper for

regeneration.

Advantages• Most mature technology• Commercialized for many decades• Suitable for retrofitting of the

existing power plants.

Drawbacks

• Low CO2 loading capacity.• High energy consumption during

high temperature regeneration.• Large equipment size.• Amine degradation by SO2, NO2 &

O

.

Conditions• Pressure 10 bar, temp: 40-60*C• Energy required =0.396 GJ/ton (for

recovery and compression till 150 bar).• Practically energy = 0.72 GJ/ton.

Chemical AbsorptionComponents: Absorber, Stripper

Process• CO2 enter packed bed absorber from

bottom.• Contacts counter-current with a CO2

lean absorbent• CO2 rich absorbent flow in stripper for

regeneration.

Advantages• Most mature technology• Commercialized for many decades• Suitable for retrofitting of the

existing power plants.

Drawbacks

• Low CO2 loading capacity.• High energy consumption during

high temperature regeneration.• Large equipment size.• Amine degradation by SO2, NO2 &

O

.

Conditions• Pressure 10 bar, temp: 40-60*C• Energy required =0.396 GJ/ton (for

recovery and compression till 150 bar).• Practically energy = 0.72 GJ/ton.

Adsorption

Fossil Fuel

Stationary combustion

system Pre Process CO2 Removal

Post Process

Pre Process

Algae Cultivation

Algae Harvesting &

Drying

Lipid Extraction

Extracted Lipid

• Commercial Products( Biodiesel, Glycerol)• Fixed Carbon for sequestration

Power