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NETRA Presentation On Carbon mitigation technologies 20 th Dec. 2011 Prakash D Hirani. N TPC E nergy T echnology R esearch A lliance Developing Economic and Green Energy Technologies. Presentation Outline NTPC overview (5 slides) About NETRA (12 slides)
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NETRA Presentation On Carbon mitigation technologies 20th Dec. 2011 Prakash D Hirani NTPC Energy Technology Research Alliance Developing Economic and Green Energy Technologies
Presentation Outline • NTPC overview (5 slides) • About NETRA (12 slides) • Carbon sequestration (26 slides)
35 Years since Inception and ‘Energizing India PAN India Presence
Performance Highlights - Operational Consistently Delivering
Capacity Addition by 2017 Long Term Corporate Plan prepared for next 21 years upto GW by 2032 to position NTPC as the World’s largest and best power producer and leader in Green Power
Global Stature Number 1 independent power producer in Asia in 2010 (by Platts, a division of McGraw-Hill companies) # 1 in the world in capacity utilization # 3 in Asia in electricity output and # 10 in the world # 3 in the world in plant availability 10th largest generator in the world
Environmental Initiatives More than 30 Million tons of CO2 has been avoided in NTPC
Focus Areas of NETRA Efficiency and Availability Improvement & Cost reduction NETRA New & Renewable Energy Climate Change Support to Stations
Feasibility of CO2 capture technology by aqueous carbonation of ash at Ramagundam Principle: Ramagundam fly ash contains 4.5% CaO (i.e. 1 T/Hr. per 200 MW unit) which requires 0.78 T CO2 for carbonation Lab. Studies conducted and established carbonation by mixing CO2 in ash Slurry with Ramagundam fly ash. Chimney ID Fan Flue gas ESP Blower Objectives: 1. CO2 Utilization 2. Reduction in scaling in ash pipelines 3. Reduction in acid consumption 4. Reduction in acidic gases from flue gas 5. Reduction in maintenance cost 6. Carbonated ash for construction purposes or Agriculture use Treated Ash Slurry to Ash Pond/disposal Flue gas Scrubber Schematic of trials • Further Activities (Ramagundam) • Design of a pilot plant for 1 T/hour of Ash Slurry • Fabrication & Installation at site • Trials at Ramagundam • Feasibility Report Carbonated fly ash after 2 days in air Tests with Dadri Flue gas
Installation of integrated biodiesel pilot unit from Pomognia fruit at Dadri Objective: Demonstrating utilization of 83% of energy from Pomognia fruit in form of Biodiesel and power instead of existing 15% (total) • Benefit: Unique technology, self powered useful in remote areas • Technique: • Previous set up produces only raw oil from fruit using expeller. Cake and shells were used as manure (Utilization 15% energy) • Now, Shell and cakes are gasified and power is also generated to make the system self driven (Utilization 83% energy) • Status: Pilot setup is demonstrated at Dadri and surplus power is also generated for lighting. Patent filed Integrated biodiesel pilot plant at Dadri From 65 Kg Pomognia Fruit Biodiesel: 8kg Electricity production: 24Kwh From 1 Hectare plantation Biodiesel: 1 Ton Electricity gen: 4800 Kwh Saving Power: 3800Kwh Payback: 5 Years
Waste Heat Recovery System: FGHR-AC Pilot Plant Hot Flue Gas Hot Flue Gas ID Fan 130oC 155 oC 12 oC 90 oC Vapor Absorption Machine (100 T R) Heat Recovery (500 kW th ) Heat Recovery (500 kW th ) 80 oC 7 oC • Objective- • Waste heat from flue gas for 100TR Air Conditioning at Ramagundam • Benefit- • Utilizes Waste heat instead of electrical power/ steam to generate Air Conditioning • Green house gas free Air conditioning. • Auxiliary Power Saving of 0.4 MU per year (266 ton of CO2) • Initial cost of demonstration pilot plant is high, but expected to come down after large scale deployment Chimney Fan Status :Technical specification for Ramagundam STPS completed, NIT by Apr2011
Aqua Ammonia Power Cycle Objective • More efficient utilization of low grade/waste heat from flue gases, LP steam, solar energy for increasing cycle efficiency and power generation Technique • Use of ammonia-water mixture as working fluid instead of water & taking advantage of variable temperature boiling and condensation Benefits Efficiency improvement by around 1 % compare to Rankine cycle in low temperature range source (150oC ; Sink-32oC) Status:
In-house development of two axis solar tracker for heliostat application • Solar tracker, tracks the movement of sun • Used for focusing • Various measuring instruments to the sun. • Photovoltaic module to the sun for harnessing more energy. • heliostat for natural lighting/solar tower Microcontroller Unit Motor Driving Circuit Real time clock Stepper motor Power supply unit • Features: • Microprocessor controlled • Track the sun with 0.072 Deg of accuracy. • Power Consumption – 28 Watt Cost - Rs. 30,000/- approximately (Market cost Rs. 5 lacs)
Why MSW to Energy ? Energy content of typical treated Indian MSW = 3766 Kcal/kg
Waste to Energy Technology : Using high pressure steam to convert municipal solid waste (MSW) into solid fuel, and it may be used as a co-firing fuel in boiler / stand alone system. • Comparison with other technologies • Use of Saturated steam for treatment (All in one process) • (other technology uses – 1. Dry – 2. Shred – 3. Compress with binders to produce pellets – Energy intensive process) • Requires low energy consumption (only steam is required) • Produce grounded fuel with uniform properties • Moisture removal is easy (Inherent moisture is removed) • (Others – Only surface moisture is removed) • Increase the shelf life of the fuel (fuel becomes non hygroscopic) • (others – Moisture will be reabsorbed by the fuel) • Removes bad / stinky odor (Sterilize the waste)
Treatment Performance Experiment Result of treated MSW * Calorific value comparable to the Indian coal Co-firing with coal Steam Treatment MSW Solid Fuel Stand alone system Kitchen Waste Paper Waste * * Proposed Usage of MSW
Plant schematic Boiler
Proposed steam treatment Requires 39 % less energy compared to traditional methods
Carbon Sequestration Carbon Capture Technologies
CO2 Management Single source CO2 Emission CO2 Capture Utilization Storage • Geological storage • Oceanic storage Physical & chemical methods Biological methods • Fuel • Chemicals • Absorption • Adsorption • Membrane • Cryogenic distillation • Bacteria • Algae • Other related items
The Energy-Carbon Conflict • There are three option to control the CO2 emission without severely or negatively changing the standards of living: • - Increase in energy efficiency • - Switching over to less carbon intensive source of energy • - Carbon sequestration • Major steps for carbon sequestration: • Capture -CO2 separation from flue gases • Transport -Probably in liquid form at high pressure • Fix -Back to mother Earth- storage in geological formation • The Separated gas may also be used for: • - Use for enhanced coal bed methane [ECBM] recovery • - Use for enhanced oil recovery [EOR] • - Making value added products
Carbon Emission Reduction Technologies Efficiency Enhancement Pre-combustion • Combustion efficiency • improvement in conventional • power plant • Low grade heat utilization • IGCC • Super critical & Ultra super • critical technology • Advanced class gas turbine • Hydrogen technology & • fuel Cell CO2 Capture During Combustion Post combustion
CO2 Capture Technologies Pre-Combustion During -Combustion Post-Combustion • IGCC • Gas turbine • Hydrogen separation • for Fuel Cell • CFBC • PFBC • Oxy- fuel • Combustion • Pulverized coal • fired based plant
Fuel IGCC Gas Shift reaction & CO2 separation H2 Air CO2 Flue gas CO2 Separation GT CO2 Fuel Pulverized coal based Power Plant Flue gas CO2 Separation Air CO2 Post Combustion approach Pre-combustion approach Oxy-fuel Combustion Fuel CO2 Oxygen Air Separation Air
Major steps for carbon sequestration Fundamental Research is required to develop Cost Effective Technology CO2 Capture Fundamental R&D may not required as Options are known Major Issues are CO2 Transport • Environmental and Safety • CO2 piping network • Long Term Integrity of CO2 storage • Monitoring and Verification • Legal Frame Work • CO2 Fixation
CO2 Capture Process Cryogenic Distillation Physical Separation High Pressure Separation Chemical Separation Membrane Separation Hybrid Separation Technologies for CO2 Separation
Indian condition FGD / SCR System To be installed Higher Generation cost CO2 Capture Flue gas Western country FGD / SCR System Already existing Need for Cost effective Technologies Carbon Capture Technologies CO2 Capture Technology • The Separated CO2 may also be used for: • Use for enhanced coal bed methane [ECBM] recovery • Use for enhanced oil recovery [EOR] • Makingvalue added products
Issues 1. Low partial pressure of CO2 Bulky equipment - Higher capital costs High Energy for pressurization Combustion in boiler at Atmospheric pressure Facts Combustion in boiler at Atmospheric pressure Low Discharge pressure of Flue Gas: 350-500 mmwc Low partial pressure of CO2 High partial pressure based CO2 separation process like Benefild or Catacrab cannot be used Low CO2 concentration in Flue Gas: GT / Gas fired boiler is 4-5% Low CO2 concentration in Flue Gas: Coal fired boiler: 13-15% Challenges in Carbon Capture
Concerns Issues Facts • Flue gas temperature is generally 140-160 °C • Present solvent based process operates at 40-50 °C • CO2 laden solvent is regenerated at 120 °C -130 °C • Cooling is very energy intensive process • Lower temperatures also pose risk of acid corrosion • Cooling is required for CO2 separation • Flue gas cooling below 50°C is required for membrane or PSA process 2. High temperature of flue gases Challenges in Carbon Capture
Cost of FGD (not mandatory otherwise), results in higher cost of CO2 capture Concerns: • The acceptable limits of SO2 for solvent process is 10 ppmv • A lime stone or wet FGD system followed by caustic soda or soda ash based scrubber is must for SO2 removal Issues: 3. SOx Removal • Flue gases from coal fired units contains 700-1200 mg/Nm3 of SOx • In amine process, SO2 reacts with amines to form thermally stable corrosive salt. • SO3 forms sulfuric acid mist in cooler causing corrosion • SOx may adversely reacts with membrane materials or solid adsorbent or may get adsorbed on adsorbent Facts: Challenges in Carbon Capture
Facts Issues Concern Level in flue gas 500- 800 mg/Nm3 NOX is removed by SCR process at 250-300 °C Cost of NOx removal results in higher cost of CO2 capture In amine process, solvent degradation due to formation of thermally stable salts Plugging of catalyst by fly ash is a problem Development of Nox / corrosion resistant process will be better option Flue gas heating to reaction temperature not possible when SCR is after Economizer. 4. NOx Removal Corrosion due to nitric acid formation Adverse reaction or adsorbed in solid absorbents SNCR at high temperature is an option NOx may degrade membrane materials Challenges in Carbon Capture
Facts: About 100 -150 mg/Nm3 of fly ash present in flue gases 5. Fly Ash in Flue Gas Issues: This causes plugging, erosion, solvent degradation etc. in solvent based process Fly ash may also plug membranes and solid adsorbents Challenges in Carbon Capture
Chemical Absorption Process • Flue gas is cooled and scrubbed in a direct contact cooler • CO2 isadsorbed in 15-20 % aqueous solution of MEA at 40-45 ºC in a Absorption Tower • The absorbed CO2 is regenerated by stripping around 120-130 ºC • Steam (3 kg/cm2) required for regeneration is supplied by a reboiler • Regeneration, the most energy intensive process, requires 2 ton of steam per ton of CO2 • Corrosion is a major issue Absorption Process most widely used Technology
Introduction of Steric Hindrance Lower Regeneration Energy Solvent Development Pri. Amine High Regeneration Energy Waste Heat Utilization of flue Gas for Reboiler Regeneration Target 100 °C
Chemical Process for CO2 Separation • Major Concerns: • In amine process, 80-90%of total energy required, is consumed in solvent regeneration • For a 210 MW coal fired boiler the total energy requirement is about 65 MWe of power. • This will bring down total efficiency by at least 30%. • This will approximately double the power generation cost
Fuel IGCC Gas Shift reaction & CO2 separation H2 Air CO2 Flue gas CO2 Separation GT CO2 Efficiency Enhancement: The IGCC Technology The IGCC Cycle • CO2 Emission: • CO2 Emission: 0.80-0.85 Ton/MW • For 200 MW Size Unit: 160-170 T/Hr • For 500 MW Size Unit: 400-425 T/Hr Improvement of overall efficiency would reduce the CO2 emission level.
Gas Separation Membrane Absorption Process Gas Absorption Membrane [CO2] [H2] [H2, CO] Polymer Membrane [T< 100C] Gas Clean-Up IGCC WGSR Gas Cleanup & Ceramic Membrane Carbon Capture Technologies: Membrane Membrane process The Cycle
Membrane CO2 Flue gas CO2 absorbing liquid Carbon Capture Technologies: Membrane Membrane process • Absorbents • Ionic Liquids • Non-Corrosive molten organic salts • Alkyl ammonium, Phosphonium, Imidazolium and pyridinium halide salt • Aqueous solution of KOH, NaOH, Na2CO3, NH3 etc. Needs large efforts on development of Membrane with right permeability & selectivity.
N2 [Primary] CO2 [Secondary] Flue Gas • Research issues • Development of high performing adsorbents based on zeolite, mesoporous material, hydrotalcte etc. • Cycle of CO2 extractions (PSA, VSA, TSA) • Process integration • Attrition issue Adsorption Cycle De-sorption Cycle Gas Cleanup CO2, N2 Carbon Capture Technologies: Adsorption The Cycle Works on a Pressure Temperature / Vacuum swing process
Technology Development for post-combustion capture of CO2 by Adsorption Netra Research on CO2 Capture CSMCRI, BHAVNAGAR ADSORBENT DEVELOPMENT CSIR (IIP), DEHRADUN PROCESS DEV & OPTIMIZATION IIT, MUMBAI SIMULATION MODELING & PROCESS DESIGN NEERI, NAGPUR ADSORBENT DEVELOPMENT
Pressure Swing Adsorption (PSA) process for CO2 capture from flue gas • Conventional amine based CO2 capture process is cost and energy intensive • PSA process is being developed as an alternative process • In PSA process • CO2 is selectively adsorbed on adsorbent under moderate pressure • Adsorbed CO2 is recovered under vacuum • Research components in process development • Development of materials for CO2 adsorption • Development of PSA process using the materials • Modeling and simulation of PSA process • Experimentation in PSA test unit and • process optimization Synthetic Flue Gas CO2 : 12- 13 % Moisture : 4- 5 % Oxygen : 3-4 % Nitrogen : 78-81 % Temperature : 50-55 °C PSA Unit CO2 purity ~ 85 % recovery ~75% • Three Indian and PCT patent application filed on CO2 • selective zeolite based adsorption materials • The PSA unit has been shifted to NETRA from IIP for • further development of the process • Pilot scale development of the process in collaboration • with GNFC and CSMCRI is under active consideration PSA test unit
Outcome Highly selective adsorbent developed at CSMCRI superior to conventional adsorbents Novel VSA cycle devised and tested at IIP Over 92% CO2 purities at 80% recoveries achieved at 55 0C from CO2 levels of 11% in flue gas. Simulation model validated
Highlights Over 80% recovery of high purity (>90%) CO2 from flue gas at moderate temperature and low pressure Preliminary estimates of Power requirements 0.30 Kw-hr/kg CO2 recovered at 550C , lower than current amine based absorption processes Base adsorbent material is commercially available Process does not generate any waste stream requiring further treatment
Micro-algae • Absorbs CO2 • Produces • Bio-fuel • Micronutrients • Animal feed CO2 Fixation Initiative • Carbon Sequestration • CO2 Capture and its geological storage is energy & cost intensive (60-80USD/Tonne CO2), • uncertain and not yet proven • India’s focus for CO2 mitigation is directed towards biological fixation/utilization of • CO2 in addition to efficiency improvement and use of renewable • CO2 to Bio-oil : Micro Algal Process • Able to produce bio-oil, neutraceuticals, cattle food, etc. • Oil content upto 40% • Potential algal species are Dunaliella, Nannochloris, Spirulina • 30 times more oil production than other energy plantations for same land • No need for agricultural land – may avoid bio-oil crop conflict • Typical CO2 consumption : 100 gm/m2/day • Requirement of land for algal cultivation is an issue • Commercial process for algae to bio-oil using CO2 from power plant yet to establish • Extensive global R&D for development of the process
Micro-Algal process for mitigation of CO2 • Algae commercially grown for nutritional, feed and specialty • products • Lipid / oil content : 2% to 40% • Algae generate 7-30 times more oil than bio-plants like Jathropa, • Ratanjot etc • Global R&D for development of the process in open pond and • photo-bioreactorsystem • Typically for a open pond system • CO2 consumption rate : 100 gm/ square meter/ day • Dry algae production rate : 20 gm / square meter / day • Oil production : 30% Algae 1000 sq. meter algae based pilot plant • Benefit : The pilot study will help in assesing the feasibility of using flue gas as CO2 • source & the possibility of producing bio-diesel
TRASFORMING LIVES THANK YOU Email hiraniprakash@yahoo.co.in 49