2007 Energy Efficiency RCF

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2007 Technical Committee Meeting12-14 March 2007 -Ho Chi Minh City, Viet Nam

Workshop on Energy Efficiency and CO2 ReductionProspects in Ammonia Production

Energy Eff iciency and CO2 Emissions in theIndian Ammonia Sector

presented by

H.S. KarangleRashtriya Chemicals and Fertilizers Limited India


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About the IFA Technical Committee

The IFA Technical Committee encourages the development and adoption of technology improvements

that can lead to greater production efficiencies and reduced emissions, as well as better health and safety

standards throughout the fertilizer industry. Our mission is to actively promote the sustainable

development of efficient and responsible production, storage and transportation of all plant nutrients. The

Technical Committee accomplishes these objectives through a variety of channels, including:

Technical and policy-oriented information materials. The committee regularly conducts surveys and

produces reports on key industry metrics, including the IFA Energy Efficiency and CO2 Emissions

Report, the IFA Safety Report, and the IFA Emissions Report. This work enables member companies to

assess their operations over time, make comparisons with similar facilities on an established level ofperformance, determine the need for technology improvements and identify good industrial and

management practices.

Regular exchange of information on technology developments and industrial practices. A key role of

the IFA Technical Committee is to encourage ongoing technical innovation in the fertilizer industry

through the development, compilation and exchange of technical information between members,

researchers, engineers, equipment suppliers and other industry associations. To this end, the

committee organizes a Technical Symposium every other year to examine progress in the production

technology of fertilizers. Each Symposium traditionally features the presentation of 30-40 new

technical papers from member companies worldwide, providing members with information on the

latest technological developments. In the intervening years, the committee holds a variety of meetingsto assess current industrial practices and standards, with an eye toward identifying key developments

of interest to members.

Technical and educational workshops and special events. The IFA Technical Committee provides

workshops designed for engineers working in the fertilizer industry, particularly those who have

recently assumed new responsibilities, and for new engineers to increase their technical knowledge.

These workshops (e.g. concentrating on nitrogen and/or phosphate fertilizer production) are designed

to improve the participants skills and broaden their vision and understanding of the entire industry,

including technology, economics, energy use, safety and environmental stewardship. Workshops also

provide engineers with an opportunity to exchange ideas, solve specific problems and improve plant

operations and profitability.

Education and advocacy. The IFA Technical Committee recognizes that customers, markets and

regulatory environments are best served by clear and concise information on the fertilizer industry and

its practices and products. Because the knowledge and expertise found within the fertilizer industry is

the best source for this information, the Technical Committee endeavours to educate policymakers,

standardization bodies, customers and the public on industry achievements, technological advances,

voluntary initiatives and best practices. The committee also encourages universities and development

centres to conduct research on fertilizer product development and production processes.


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(as provided by the author for distribution in Ho Chi Minh City)

Energy Efficiency and CO2 Emissions in the

Indian Ammonia Sector

Abstract

Ammonia production is an energy intensive process operation where energy is consumed

both in the form of feedstock and fuel. Currently the efficient plants operate at an energy

level of 7.0 GCal/MT which is quite close to the practical minimal energy required for

production of Ammonia. The primary driving force for reducing energy consumption in

such ammonia plants is the cost of energy for which India is dependent on imports.

Majority of the ammonia plants in India are combined with urea production. Urea is a price

controlled commodity. Thus the cost of production of urea and thereby ammonia is

indirectly controlled by Government of India. The Government policies are directed

towards improving energy efficiency in ammonia plants and bringing them up to par with

most energy efficient plants. This is a formidable task given the vintage of Indian plants

and differing feedstock. The results, however, are encouraging. The average energy

consumption per ton of ammonia has dropped currently to around 9.1 GCal/MT from the

highs of 20 GCal /MT that was prevailing in the 1960s.

This paper describes the levels of energy efficiency in Ammonia plants in India and

measures taken to this endeavor. Further energy saving is becoming increasingly capital

intensive. The paper highlights the benefits of carbon trading under the UNs Clean

Development Mechanism for increasing industrial energy efficiency.

Contact details:Rashtriya Chemicals and Fertilizers Limited

Priyadarshini, Eastern Express Highway, Mumbai 400 022, IndiaTel: +91 22 2404 5191 - Fax: +91 22 2404 0028

E-mails: [email protected] - [email protected]

All papers and presentations prepared for the IFA Technical Committee Meeting in

Ho Chi Minh City will be compiled on a cd-rom to be released in May 2006.


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Energy Eff iciency and CO2 Emissions in theIndian Ammonia Sector

1. Overview

India ranks second in the world in production of nitrogenous fertilizer. A whopping 87% of thisis urea, which is produced through the ammonia route.

India produced 12.8 million MT of ammonia in the year 2005-06. Ammonia production is oneof the most energy intensive processes in the Indian Industry. Currently, the average energyconsumption is around 9.1 Gcal/MT of ammonia.

2. Feedstock wise capacity of Ammonia

The Indian ammonia plants are of various vintage and use differing feedstock. The choice offeedstock is dependent on the availability of feedstock and the plant location.

Feedstock Percent of TotalNatural Gas 60.2Naphtha 16.3Fuel Oil 8.5Others 1.2External Ammonia 13.8

Source: FAI statistics 2005-06.

3. Overall energy consumption scenario

Accelerating economic growth in India coupled with increasing population is putting pressureon energy needs of India. The energy needs are set for four fold increase by the year 2025.India is dependent heavily on imports for its energy needs. Currently 70% of hydrocarbondemand in India is met through imports.

Sustained efforts for efficient use of energy made over the years in the Indian ammoniaindustry have given phenomenal results. The average energy consumption per ton ofammonia has dropped from the highs of 23 Gcal /MT that was prevailing in the 1960s tocurrently around 9.1 Gcal/MT. The energy efficiency could be achieved due to several factors

including switchover of feedstock, advances in process technology, improved catalysts,higher stream sizes, increased capacity utilization and improved reliability.

Energy Consumption Trend

Over the years, the energy consumption of Ammonia has shown marked reduction.

Year Ammonia energy consumption Gcal/MT

1959-60 23

1969-70 15.25

1979-80 14.77

1984-90 11.551995-96 10.5

1999-2000 9.5

2005-06 9.1


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The energy consumption in production of ammonia is dependent on type of feedstock andthe consumption pattern is as under:

Gas based plants 7.56 to 9.90 Gcal/MT

Naphtha based plants 8.11 to 10.53 Gcal/MT

Fuel Oil based plants 11.45 to 20.81 Gcal/MT

4. Where does the extra energy go?

The most energy efficient ammonia plants in the world consume 6.7 Gcal per MT ofammonia. Inefficient ammonia plants consume much higher energy. A systematic breakdown of the energy consumption steps leads to gap analysis that helps to identify areas forimprovements.

Out of the net energy input of 6.7 Gcal/MT of Ammonia about 66.3% of the energy, i.e 4.44

Gcal/MT goes into the ammonia product as net calorific value.

The balance 33.7 % of the energy can typically be attributed to the following:

A comparison of actual energy consumption in any operating ammonia plant with thispractically achievable level will identify areas for improvement. There may be various optionsfor improvement but final choice depends on many factors including level of investmentneeded for bringing in the improvement.

Some of the possible areas of improvement are:

More efficient compressors and their drives.

Improvement in CO2 removal system including employing low energy CO2 removalsystems.

Introducing combustion air preheat.

Lowering steam carbon ratio.

Lowering pressure drop in front end.

Purge gas recovery.

Increasing per pass conversion in synthesis.

Providing distributed control system.

Fuel gas expander.

Generating High Pressure steam from waste heat.

Mechanical energy loss in drives and loss in steam condensers 16%

Loss on account of condensation, separation and cooling ofammonia produced

5%

Heat losses in inter-stage coolers of compressors 5%

Energy for CO2 removal 3%

Stack losses( Flue gas) 1.5%

Losses due to inadequate insulation 1%

Other losses 2.2%


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5. A case study

a) A 900 MTPD ammonia plant in India employing technologies of eighties wasrevamped in the year 2006. The revamp was focused on following objectives:

Reduction in the specific energy consumption.

Improvement in reliability.

Utilizing design margin to enhance capacity.

Minimizing the downtime to incorporate the changes.

The following modifications were selected and implemented:

i. Up-gradation of primary reformer

The Primary reformer up gradation consisted of:

Rearranging the staggered row of reformer tubes into Single row of catalysttubes for better distribution of heat.

Increasing the reformer tube diameter.

Installation of triple decker catalyst.

Replacement of reformer burners by force draught type.

Replacement of inlet distributors, pigtails and outlet hot collector.

Modification of roof, floor and its refractory.

Installation of combustion air pre-heater in reformer convection.

ii. Modification in Steam super heater

The auxiliary steam super heater of the plant was suffering from high degree of

inefficiency. There was no combustion air pre-heat. Moreover the stacktemperature was 465 degree C. This deficiency was corrected by providing forfeed gas and combustion air preheat in the flue gas.

iii. Process Air Compressor

To cater to increased requirement of air for secondary reforming as well as toimprove the compressor efficiency, the process air compressor internals werechanged.

iv. Carbon Dioxide Removal System

Improved tower packing, incorporation of a hydraulic turbine to recover energyfrom rich solution, a five stage flash vessel and use of steam compressor are themeasures employed for energy reduction in Carbon Dioxide removal system.

v. Condensate Stripper

The low pressure process condensate stripper was converted to mediumpressure condensate stripper whereby the steam used for stripping is recycledback to reformer as process steam. To this extent the steam addition to primaryreformer has been brought down. Further, the condensate quality has alsoimproved and fed directly to polishing unit.

vi. Synthesis

Major modifications were also carried out in synthesis section that includedinstallation of S-50 Converter, a loop boiler and replacement of the synthesis gascompressor that was inefficient and prone to frequent downtime.


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b) Energy Saving

The various revamp measures are expected to reduce the energy consumption in thefollowing manner:

Sr.No. Scheme

Estimated Savings(Gcal/MT)

1 Primary Reformer 0.63

2 Aux. Steam Super heater 0.08

3 MP condensate stripper 0.25

4 Carbon Dioxide removal system 0.54

5 Other schemes (Synthesis, turbines, compressors etc.) 0.76

Total 2.26

The energy consumption prior to revamp was of the order of 11.0 -11.2 Gcal/MT of

ammonia on sustained load operation. After revamp the energy level of 8.7 - 8.8Gcal/MT of ammonia is expected on annualized basis. The other consequent benefitsintended are improved operability and reliability.

The total time required for implementation was 24 months. This could be achieved bymaximizing supply of prefabricated items and erection of the same during normaloperation. Following the modifications, the steam carbon ratio has been reduced from4.04 to 3.2 and reformer stack temperature brought down to 150 deg C.

The cost of the above modification is about US$ 55 million.

6. Energy efficiency and Carbon Dioxide emission

Typically energy saving in ammonia production process ultimately translates into reduction infuel consumption. Reduced fuel consumption means burning of lesser quantity of fossil fueland corresponding reduction in CO2 emissions. CO2 is a greenhouse gas. The projectsundertaken in a developing country causing reduction in greenhouse gas emissions qualifiesfor Certified Emission Reduction (CER) credits. An emission reduction of one MT of CO2qualifies for one CER. These CER credits are tradable and can be used to contribute to theemission reduction commitment of industrialized countries. All these projects, however,should satisfy additionality criteria under Clean Development Mechanism (CDM) of KyotoProtocol.

CDM: Additionality Criteria.

Emissionadditionality:

The project should lead to real, measurable and long termGreen House Gas reduction.

Financingadditionality:

The funding for CDM project activity should not lead todiversion of official development assistance.

Technologicaladditionality:

Investments should be for newest and sound technologies.

The project, therefore, needs to be carefully configured to qualify for CDM support.


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In India ammonia producers are linked to urea production facility. Urea is a price controlledcommodity where the selling price is regulated by the government. Even feedstock gas pricefor fertilizer is controlled by the government. Any capital investment in energy efficiencyproject is therefore subject to these restrictions. Further, it is well known fact that as energyconsumption pattern nears to its most efficient level it becomes increasingly capital intensive.Under such circumstances, financial benefits from CDM can improve the viability of theproject. In many cases such benefits of CER credits under CDM is acting as a booster inpursuing energy saving measures in ammonia plants.

7. Type of CDM projects

In ammonia industry the following type of CDM projects are pursued:

i. Energy Efficiency Improvement Projects

This is the most common type of CDM project that is applicable to ammonia Industry.Energy efficiency of 1 Gcal roughly translates into 0.2 CER. A 1000 MTPD ammoniaplant bringing about 2 Gcal/MT reduction in energy is capable of generatingapproximately 132,000 CER per year of operation. The methodology to be applied forsuch schemes for registering the project under CDM is well established. Someammonia plants in India have already registered their projects under thismethodology. Many other plants are on way to getting their projects registeredincluding the plant described in the case study.

ii. Feed Switch Projects

Switchover of feedstock from Naphtha to Gas leads to reduction in CO2 emission andthus qualifies for CDM benefits. However, there is no approved methodology as yet.Some projects have progressed on this front and are hopeful of getting registeredunder CDM once the methodology gets approved. There is a potential to generate atleast 2 million CER per year from switch over of feed in Indian ammonia plants.

iii. Carbon Dioxide Recovery (CDR) Projects

If the gas which is feeding to the ammonia plant is lean (less in carbon content) thenthe entire ammonia produced from the plant cannot be converted to urea. Themajority of ammonia plants in India are linked with urea production and hence there isa need to maximize CO2 generation so that ammonia produced is completelyconverted to urea. One of the ways to overcome shortfall in CO2 production is puttingup a CDR unit to recover CO2 from Flue gases exiting the reformer stack. It is highlycapital intensive but benefits derived under CDM will help in improving the financialviability. A methodology is in advanced stages of approval.

iv. General Waste Heat Recovery Projects connected with ammonia

Other waste recovery projects associated with ammonia production facility isdeveloped under this category and there are few approved methodologies which canbe adopted to develop them into CDM projects.

8. Basic steps towards registration of a Project Activity under CDM

To register a project activity under CDM the following basic steps need to be followed:

Preparation of Project Design Document (PDD).

Submission of PDD to UNFCC through Designated National Authority.


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Use of approved methodologies for the project under consideration.

Validation of CDM project Activity.

Registration of the CDM project activity.

9. Conclusion

Modern Indian plants are at par with world class plants. The older plants have kept pace withthe developments in technology and have put in serious efforts to bring energy efficiency to acomparable level. The way forward is to switch over to clean feedstock and fuel like gas andliquefied natural gas and upgrade & modernize with respect to technology, equipment andmachinery. While doing so the plants can avail the benefits under CDM for reducing greenhouse gas emission.

Documents

2007 Energy Efficiency RCF