CO2 Utilization and Optimization for Benefit to the National Economy

Overview

Since times immemorial, there has been emphasis towards protection of the environment and its sustainability. The Industrial Revolution however had its own advantages and side effects. While life in general has improved substantially based on the benefits of the Technology and Mechanical devices emanating out of the Industrial Revolution, the not so welcome ingredients of the Technological Revolution alongside, have also become a stark reality. The Power Plants, Steel Plants, Hydrocarbon facilities etc. are major facilities where the environmental pollution as such, has gradually emerged as a serious area of concern. In the various International meets as well as, the policy formulation centres within the Nation, discussion for mitigation of the receding quality of environment remains a major concern and a dominant topic of discussion and debate. The rising levels of the sea, flash floods, melting of the icebergs, gradual change in the ambient temperatures and the distinct shift of the weather cycles are obvious areas of concern. Most of these adverse changes are believed to be resulting out of the grave environment pollution hazards, created on account of Industrialization and somewhat unorganized development.

One of the most significant problems that is encountered by the industry, is the consistent pumping of gaseous emissions into the atmosphere. Incremental SOx, NOx, Particulates and CO2 are an extremely distressing environmental problem with which, almost all the Nations are currently seized with. The Developing Nations more so, are caught between the horns of a dilemma of sorts. On the one hand, they need to provide to industrialization and growth to sustain the rising demands of people, while on the other, the pressures to protect the environment and its pristine quality alongside, has to be ensured and balanced.

The recognition of the CO2 increment in the Atmosphere being a Major problem is a recognition of recent origin. No wonder that ever since the global warming discussion has picked up momentum various measures to combat the Cor2 Intensity is evident. While the discussion towards carbon capture and mitigation is certainly a matter of great attention the talk of Electric vehicles too has gained momentum. Had the recognition that the CO2 could have deleterious effect on the environment been understood a little earlier, perhaps the electric vehicle revolution would not have waited for this long to gain the attention and focus that it is inviting now and certainly would not have faded into obscurity as it did in early 1900.

The World is committed to the commitments of COP 21 though it focuses primarily on the Carbon intensity and the fallout thereof across the globe. Notwithstanding the same the avenues are now being opened up to investigate the various other means which could help mitigating the CO2 related problems for instance through useful utilization of CO2.

Amongst the serious polluters to the environment, particularly the air quality, the Power Plants, Hydrocarbon Complexes and the Steel Plants obviously stand out.  It may be worthy of reiteration, that a typical economically sized plant in these industries leads to incremental pollution to the levels which needs to be mitigated. This is extremely important as environment quality control and Management is of extreme importance. The various quality stipulations with respect to various pollutants are mentioned in table below: 

The above numbers are certainly a central objective of constructing an existing or new facility. It is also noteworthy, that while specific measures with respect to the SOx, NOx, Particulates and their entrapment, as part of environmental sustainability projects are being implemented variously in the Complexes, there is however, very little that is happening for CO2 abatement on the ground, though of course one cannot complain with respect to the efforts that are being made to circumvent the same.

As a matter of fact, CO2 as a gaseous compound is fairly stable and is certainly not easily transposed into useful chemicals and other materials through which, CO2 reduction and abatement could be ensured. Even while some progress has been made in this direction, it is essentially towards developing intermediate products, which would lead to CO2 recycling in one way or the other. Utilization of CO2 to generate chemicals, fuels etc poses a serious question of energy requirement. Some of these issues are perhaps now getting sorted out through the wide spread availability of zero carbon emitting energy sources, such as solar and wind which perhaps, could be instrumental in effecting a transformative change in the carbon cycle. Most of the work however in this direction, continues to remain in the R&D Stage, though of course, it is beginning to gradually become the Centre stage of attraction.

CO2 Abatement

Global warming has been a subject of intense debate, discussions and also concern amongst various Nations and COP Summits. The incremental CO2 being emitted to the atmosphere from the industries, certainly has been under focus in this context. The point at issue has been since CO2 apparently has not been able to be made useful in effecting recycling processes. It is generally considered to be a molecule of relatively less importance and hence is rejected. This has had its own repercussions in terms of the all-round negative impact on the environment which ensues on this account. Consequently, CO2 abatement has remained a subject of focus and concerted R&D

Amongst the various initiatives that are being taken towards CO2 management, two major areas of focus are visible:

1.    Carbon Capture and Storage

2.    Carbon Capture and Utilization

Carbon Capture and Storage

Given the fact, that not much headway could be made towards recycling of CO2 in chemical processes except urea, the vast quantities of CO2 being produced perforce are being let out to atmosphere. Carbon capture and storage therefore, emerges as the first area for CO2 abatement. Over four to five decades carbon dioxide has been used for enhanced oil recovery as one of its major opportunity to utilize/sequester. In the process, crude production has been enhanced and CO2 utilized to fill the reservoirs to remain stored in the same for posterity. Considerable amount of carbon dioxide has been abated through this mechanism, particularly in the Western World, including USA and Europe. However, this form of utilization of enhanced oil recovery has only been partially utilized in India. The geographical set up of the country and lack of clusters of hydrocarbon exploration which would facilitate such solutions are scarce, except for certain pockets in Bombay High. 

In early 2000, various incentives to provide tax credit for abatement of CO2 and its sequestration led to a lot of scientific development, to examine the feasibility of other forms of CO2 abatement. Another major area, which appeared to be somewhat successful, was to pump CO2 into mountainous terrains, which had pre-dominance of calcium and magnesium minerals in it. This was essentially to enable abatement of CO2 through formation of carbonates of calcium and magnesium. A lot of CO2 was abated elsewhere in the world in this way. Both these technologies enabling large volumes of CO2 to be disposed off, are solutions which inevitably will continue to abate CO2 for times to come.  

Another major technology which is under focus and development is with respect to CO2 abatement from the Coal Based Power Plants, wherein CO2 is utilized for algae formation. This would in turn be utilized for production of fuels. While work on the subject remains a process in continuity, its success to a large extent is still under question as vast tracks of land and waterways are required to harness the algae and green mass through utilization of CO2. An alternative of considering seaweeds as a potential area for growth of green mass has also been under consideration. The transportation and handling cost of CO2 however, remains a technological and engineering challenge as economics remains to be established.

The major problem with CO2, in addition to its own stable nature is the fact, that most of the CO2 is rejected from processing facilities at relatively low pressures, closer to ambient conditions. This in itself warrants a lot of energy penalty in case CO2 were to be utilized for conversion to other substances. The CO2 molecule is stable and breaking and bonds through a chemical/catalytic method often requires a large amount of energy. This effects the life cycle analysis of emission reduction process too. The recent headway into renewable energy dominated by solar and wind is somewhat a solution in this direction, wherein large quantum of energy would be available at practically zero additional carbon generation. Again, the problem of such modes of power generation remains availability of vast tracts of land and specific meteorological conditions before the same could be effectively harnessed.

Utilization of CO2 for food preservation is another opportunity, by which CO2 could be utilized for refrigeration. This of course, is only an intermediate step in abatement of CO2 as solid ice upon melting would lead to CO2 formation to be let out to atmosphere anyway.

The problem of CO2 abatement therefore, remains a huge challenge and unless parallel measures, in addition to the carbon capture and storage are supplemented by chemical utilization of CO2 as a feedstock, possibly, the problems with respect to the CO2 abatement would continue.

CO2 Utilization

All this has led to a very high level of research particularly in USA and Germany, to examine the options of re-use of CO2. It is known that re-use of CO2 is highly energy and cost intensive and as of now it is not easy to compare the performance and commensurate benefits thereof. Till date, the economic benefits of CO2 conversion remains in early stages of development and its effective direct benefits on the environment also are not fully available or quantified. 

Gasification

Gasification of coal and its utilization to chemicals is one of the important technologies which is making prominent headway in countries, where the energy import pressure is high. Gasification remains the backbone of the process as in addition to power generation, production of chemicals such as methanol, DME are important chemicals through which, lot of carbon can be sequestrated. In addition, the synthesis gas produced forms a critical feedstock to the Fertilizer Complexes. 

Slowly but importantly, gasification technologies for exploitation of coal to Power/chemicals on the above lines is gaining popularity. China certainly has led the way in this direction though of course, the aggressiveness with which they have supported coal to chemicals with or without adequately sequestering CO2 is perhaps, an area of concern and certainly, has led to a lot of pressure on them to moderate their coal based technology utilization. However, this is an important route and if both the synthesis gas, as well as CO2, are integrated in purposeful use one major solution for CO2 abatement is there for asking!  The Talcher Project in India in this connection, possibly would a land mark Project through which, fertilizer production for utilization of CO2 is one of the key objectives.

Additionally, conversion of synthetic gas to methane is also being addressed for pumping gas into cross country pipelines to cater to the rising demand of gaseous fuels. The sustained emphasis of Niti Aayog for converting coal to methanol, and perhaps also to DME with CO2 utilized in the Fertilizer Complexes, possibly is the technology route which will gain momentum in India and in other countries. These facilities wherein power, fertilizer and hydrocarbon/chemicals production can be initiated in a single location with maximum protection to the environment is sure to attract attention. Incidentally, gasification can be an extremely environment friendly technology, if integrated appropriately.  

Slurry for Desulphurization

The central problem of CO2 emissions from the Power Plants at relatively low pressures remains an issue. One important area which possibly can emerge as a reasonable solution, could be to convert most of the carbon dioxide let out from the Coal based Power Plants, into lime slurry in presence of magnesium and calcium salts, for the lime to be utilized for desulphurization of the flue gases from the Power Plant itself.

Specific ores would be required for enabling the CO2 recycling for formation of the lime based for desulphurization. Again the power requirement for re-compression of the carbon dioxide could be an important area of concern to be addressed. The disposition of calcium sulphate formed in the process of desulphurization as gypsum could be in Cement Plants, Construction Industry, roads as well as in Agriculture. It is believed, that now that desulphurization of the gases from coal based Power Plants is in the focus of the country, under the direction of the Hon’ble Supreme Court, possibly a holistic solution to pollution abatement and carbon dioxide venting could be looked into.

This article is essentially divided into two parts. Part 1 is essentially focuses on the carbon capture mechanism though utilisation of CO2 remains a central objective through a strategic route which focus of utilisation into one of its more popular and large scale utilisation viz production of Ammonia. This can also be termed as a short term or immediate measure to mitigate the continuously rising quantum of Co2 In Air. Part 2 essentially focuses on the more long term solution of utilising CO2 as a feedstock to manufacture chemicals and petrochemicals. The Research in this area is underway and perhaps in the next 5 to 10 years this could possibly be of significance wherein CO2 perhaps would no longer be looked into with contempt and discomfort. It could emerge as a more useful feedstock for certain important and significant chemicals.

Carbon Dioxide to Chemicals  

The other major area which could be important to consider is the conversion of CO2 to chemicals. While CO2 to urea is a known established process, the other processes with respect to CO2 formation to poly carbonate is an area of tremendous interest and research across the world.

It is worthy of notice, that about 3500 Million tons of CO2 worldwide is added annually into the atmosphere and consequently, all the means of CO2 sequestration be it EOR storage, fuels generation, gasification, all of these would be useful. Additionally, utilization of CO2 for production of cyclic carbonate, and poly carbonates which have a large worldwide consumption annually could be an area of interest. The current mode of formation of poly carbonates is through the Bisphenyl route.  However, an alternative to that, could be the controlled polymerisation of CO2 and epoxides in presence of catalyst to produce poly carbonates Propylene Poly Carbonates.

These poly carbonates could be utilized for formation of several other important materials. The synthesis of cyclic carbonates could be utilized to form propylene poly carbonates, which is in turn potentially utilized as a binder resin, to serve as a substitute for thermosplastics in several applications including medical devices. Several plants to produce Poly Carbonates and Propylene Poly Carbonates are in pilot stages wherein, with the utilization of propylene oxide to perform carboxylic reactions for production of PC-PPC is making interesting advancement and enabling utilization of CO2 as a feedstock.  

Detailed experimentation reveals that with the first charge of catalyst introduced into process facilities, about  13.7 TPH of PPC and 0.8 TPH of PC can be produced by using 8.7 TPH of CO2 alongwith 6.6 TPH of propylene oxide. The processes established that the initial catalyst to the tune of 36 Kg/hr is recyclable to the extent of 90%. The key area of course remains the pressure profile of the reaction which is invariably high and in the range of 60-70 Kg/Cm2g when PPC is intended to be produced. For CO2 to be provided at such pressure would imply a lot of power consumption and consequently, if CO2 is available at a relatively higher pressure source then of course, a lot of value addition can be achieved. The conversion of CO2 to poly carbonates is an important area of research and it is expected that in the next 5-10 years’ time, this technology will begin to gain momentum and high degree of commercialisation. Perhaps, it could be another positive way of looking into the utilization of CO2 as feedstock for partial abatement of the environment.

In the ensuing paragraphs, a detailed study of utilization of CO2 for urea production from the port based refineries and their Hydrogen Plants to provide CO2 as feedstock alongwith imported ammonia to produce urea has been conducted. Huge techno-commercial benefits are foreseen for the same. For the other refineries, which are land locked, possibility of integration of CO2 for production of poly carbonates could be an important area of study. A brief for the same in terms of broad capex/opex analysis has also been elaborated.

Integration of CO2 in the Utilization Cycles for Optimization

One of the major areas, where perhaps lot of work can be carried out in a country like India, is perhaps the Refinery segment. This would entail integration of a significant quantum of CO2 produced from the Refineries to Fertilizer Complexes as well as, for Utilisation in development of chemicals in the times to come.

As we are aware, on account of the environmental pressures, the quality of fuels is being gradually improved such that, the sulphur levels in the distillates is being gradually reduced to extremely low levels of less than 10 ppm. This is with the intention of reducing SOX emissions from the automobiles as a measure of pollution abatement. This objective however, warrants that a very large degree of hydrogen should be available for affecting the desulphurization of distillates. Typically, therefore all the Refineries in general, are equipped with one or more Hydrogen Plants to cater to the process requirements.

India of course is scarce in terms of availability of natural gas which incidentally, is a premier feedstock to serve the Hydrogen Plants. Instead therefore, light naphtha produced within the Refineries invariably, is utilized for production of Hydrogen.  

The production of hydrogen involves upfront desulphurization of naphtha, followed by a steam reforming reaction wherein, the hydrocarbon is converted into hydrogen, carbon monoxide and carbon dioxide. The carbon monoxide produced as part of the reforming reaction, is further shifted towards the production of hydrogen, in presence of steam and selective catalyst resulting in incremental production of carbon dioxide, alongwith enhanced hydrogen. In a way therefore apart from the Captive Power Plant in the Refineries, the Hydrogen Plant forms the major source of CO2 produced from a Refinery.

As a corollary, there are a significant number of Fertilizer Complexes in the country, which require Hydrogen to be produced within the Fertilizer complexes for production of ammonia. In the early days liquid feedstock in general was being utilized for production of hydrogen in the Ammonia Plants. These have gradually been switched over to LNG/Gas as a measure of system efficiency improvement, and better economics. This certainly has made the efficiency of the Ammonia Plants increase and also effectively has reduced production of the net CO2 from the Hydrogen generation facilities.

In the Ammonia/Urea Plants, Hydrogen and nitrogen are combined together to produce Ammonia, which is further chemically reacted with carbon dioxide to produce urea. In general, the carbon dioxide produced captively in the Hydrogen generation facilities for Ammonia Production, is utilized as feedstock to the Urea Plants and hence to a large extent the CO2 balance is met within the Fertilizer Complex premises.

Hydrogen Generation Process

Typically, the Hydrogen generated in the Reformers comprise of 4 major sections viz:

1.    Feedstock Purification System

2.    Reforming Section

3.    Shift Section

4.    PSA Section

The PSA section is intended to recover pure hydrogen from the mix of gases downstream of the shift section. In the process it leaves behind tail gas comprising essentially of CO2, CO, small quantities of H2 and residual hydrocarbon. The important part is that, while the stream inlet pressures to the PSA Unit are in the regime of 20-24 Kg/cm2g, the tail gas is available almost at ambient pressures or slightly below that. This tail gas is generally utilized within the reformer as fuel, wherein all the residual hydrocarbon is combusted and the resultant CO2 from the combustion as well as the CO2 laden in the tail gas stream is vented to atmosphere. The quantum of CO2 produced is extremely large and is directionally dependent on the size of the Hydrogen Plant. The key and interesting fact however is that the gases available after the shift section comprise largely of Hydrogen + CO2 + CO + Residual Hydrocarbon at a relatively higher pressure of 22-24 Kg/Cm2g. These conditions are somewhat similar, as to the ones, which are available in the Hydrogen Plant equipped in Ammonia Units of the Fertilizer Complexes. Consequently, therefore, since CO2 is utilized as a feedstock in the Urea Unit, in case the CO2 is recovered from the Hydrogen Plants and the Refinery at a higher pressure, the same could be utilized in the Urea Units of the Fertilizer Complex. The central point however is, that the Fertilizer Plant should be in close proximity of the Refineries to avoid long leads of CO2 Pipelines and minimization of transportation costs. 

The critical issue is the fact that the feedstock for the generation of hydrogen in the Ammonia Plants is natural gas or LNG, which is essentially imported. The point therefore begs the question, as to why we would route natural gas or LNG for production of Hydrogen in the Ammonia Plants? Instead Ammonia which is freely traded in the world could be sourced and utilized straightway as a feedstock for the production of urea by utilization of the CO2 available at a relatively high pressure of Hydrogen Plant of the Refineries.

It is observed that Ammonia is freely traded in the world and in general, is found to be available in surplus. Also since the natural gas prices in major gas exploration centres, such as USA, USSR, Middle East is extremely low, the Ammonia prices in general, are fairly suppressed. At a time when Shale Gas in USA was only a matter of discussion, the natural gas prices were high, and so were the prices of ammonia. However, natural gas now being available at 1 to 2 $/MMBTU in several countries and being produced in bounty, have brought down ammonia prices significantly which keep floating between $ 300/Ton to   $ 400/Ton. These prices have remained fairly stable in the past couple of years and with the prognostication of gas being available in large quantity on a sustained basis, there is a good reason to believe that Ammonia prices would remain fairly stable in the price band mentioned above or even lower. This certainly calls for re-visiting of our National Strategy towards utilization of imported gas in a more effective manner, rather than utilize it for production of Hydrogen for ammonia production in Ammonia-Urea Plants

The imported ammonia and CO2 from Refineries, could meet the requirements of the Urea Complexes, either existing or new ones. Since India is an agricultural country and urea is pre-dominantly subsidised, it is important to assess whether there are possibilities of reducing the prices of urea, or reducing cost of production of urea itself, through the proposed mechanism of setting up Urea Plants based on imported Ammonia and CO2 from the Hydrogen Plants of Refineries provided at a relatively high pressure of 20-24 Kg/cm2g.

A case study to this effect is revealing. The important part alongside is that the CO2 served by the Hydrogen Plants from the Refineries is relatively pure and free from contaminants.

Hydrogen Capacities and Potential CO2 Recovery

As we are aware, India has gradually emerged as a Refining Hub in the recent times and continues to add refining capacity to cater to its rising distillate demands. A brief review of the existing major Refineries excluding the North East Refineries reveals that the capacity of Hydrogen Plants set up in these plants alongwith their effective CO2 potential is as below:

All the above Hydrogen Plants in general are fed with light naphtha as feedstock except for those plants where the switchover from Naphtha to Gas has taken place for instance Paradip, HMEL, Mathura part Panipat etc. For the others the process of conversion is critically dependent upon availability of gas. 

It may be highlighted, that in case these Hydrogen Plants are integrated with gas, significant quantum of liquid feedstock could be displaced, which can either be utilized for augmenting distillate pool or to serve as feedstock to the Petrochemical Complexes.  We shall examine all these aspects as we go along. For the moment, it is important to recognise that significant quantum of CO2, which any way is finding its way into the atmosphere can perhaps be recovered and utilized as feedstock to the Urea Plants, in case Ammonia is imported and Reformers are not set up as part of the Fertilizer Complexes but instead connected with the Hydrogen Plants of Refineries for availability of CO2.

Typical World Scale Size Ammonia/Urea Plant

A typical world scale size Ammonia-Urea Plant in general, comprises of 2200 TPD of Ammonia Plant integrated with 3850 TPD of Urea Complex. All the ammonia produced within the Ammonia Plant is typically utilized as feedstock to the Urea Complex. Of course, Ammonia can be utilized for many other products, such as Nitric Acid, Ammonium Nitrate etc, but for the immediate purposes of discussion, a one to one correlation between the Ammonia-Urea Complex, as mentioned above can be considered.

The point at issue is that commensurate with 2200 TPD of Ammonia Plant, the typical CO2 production is to the tune of 1650 TPD, which is all captively consumed in the Urea Complex. Consequently, a world scale complexes are to be set up or closely supported by capacities closer to 1650 TPD of CO2 would have to be made available.

Another important point at issue is the fact, that most of the Refinery Complexes listed above are likely to undergo expansion, both in term of capacity, as well as in terms of inclusion of facilities to upgrade their product qualities for which, additional hydrogen capacity would inevitably be required.

Port Based Refineries and Proposed Urea Complexes

From the above list of Refineries, it would be important to shortlist the Refineries which are port based such that, to start with, only those are considered as opportune facilities for integration to existing or new Fertilizer Complexes. The following Units stand shortlisted therefore.

From the above, it may be noted that Paradip & CPCL are the two facilities where perhaps the Ammonia Plants may have to be rationalized as 1650 TPD of C02 is not fully available. For Vizag Refinery since the Expansion + the Existing Facilities are located together the net production is in the positive domain only and consequently availability of CO2 in large quantity is not an issue. In view of the above, the Ammonia Plant capacities in the various locations mentioned above can be inferred as below:

*the C02 production from existing Hydrogen Plant + Hydrogen Plant of Expansion have been combined to support the proposed Urea Complexes.

The above table signifies that majority of the world scale capacity plant can be supported in the Complexes and a total additional urea production of 31,715 TPD through 10 additional Urea Plants can be foreseen. This when built in 4-6 years time, could cater not only to the additional urea demand in the country, but also enable sufficient surplus urea available, either for export or for production of value added products such as, Urea formaldehyde etc.

Ammonia Urea Economics

For the proposition to be justified it is important that the net revenue gain should be foreseen. As mentioned above the Urea prices in general, have been varying between $ 300-500/T in the past few years and have more or less settled around $ 310-320/T in the recent past. Given the directional price of natural gas to be generally low, it is expected that Urea prices may continue to rule around this number. For the purposes of study, Urea prices are considered as $ 320/T. Also for the study, the Ammonia Prices are considered as $ 405/T, although they have been ruling around $ 325-350/T in the recent past. Nevertheless, a more conservative number of $ 405/T has been considered for study. Based on the urea capacities mentioned above and the potential ammonia quantity that would be required to support the commensurate urea production from which all the facilities tabulated above the following broad inferences may be drawn:

Total Revenue out of Urea production @ $ 320/T              $ 3400 Million

Total Ammonia purchased @ $405/T                                     $ 2495 Million

Net Revenue Accrual/ Annum                                                $  905 Million OR                                                                                             Rs.6345 crores

It is worthy of notice that the Urea Subsidies is close to Rs.70,000 crores per annum as of now. This could be in some way be obviated on account of the price differential gain based on the above strategy (Saving as above + saving in gas required required to produce ammonia). In the above analysis, the CO2 sourced from the Refineries is considered to be available free of cost. However, even if some value is added to the same, the savings would be substantial in terms of the differential net price between Urea Produced domestically and imported ammonia.

Capex Saving

The other major benefits out of this Integration would be in terms of the fact that the Ammonia Complex and its associated Utilities and Offsites/Financing Charges and IDC to support the same would be eliminated. This would be a significant gain. A typical Ammonia/Urea Complex costs about Rs.4800 crores, for which the effective share of the Ammonia Complex and its supporting facilities computes to about Rs.2825 crores. These numbers are typically for world scale Grassroots Complex of 2200 TPD of Ammonia and 3850 TPD of Urea. These numbers when pro-rated to the proposed Ammonia/Urea Complexes, as mentioned above, the net capex saving towards the Ammonia Plant itself works out to Rs.23,620 crores, which would be a net gain. This can be further moderated considering CO2 Recovery and transportation costs of Rs.500 crores/facility i.e. Rs.5,000 crores. The net saving still would be a whopping Rs.18,620 crores. In fact, this cost saving itself would be reasonably good enough to support a Grassroots World Scale Size Olefin based Petrochemical Complex. Consequently, therefore, there is immense sense in examining this potential opportunity.

LNG Saving from the Ammonia Plant and Naphtha Displacement

Typically, 2.1 to 2.2 MMSCMD of Natural Gas is required to support world scale sized Grassroots Ammonia-Urea Complex of 2200/3850 TPD capacity. With the Complexes mentioned above, where the Ammonia Plant are not required, as the same is proposed to be imported, the effective natural gas saving would be significantly high.  For the complexes, as mentioned above, i.e. Paradip, Haldia, MRPL, CPCL, HPCL Vizag-1, Kochi and HPCL Vizag Expansion, the total effective LNG saving would be to the tune of 18.1 MMSCMD of gas or an equivalent 5035 KTA of LNG. It is worthy of notice, that for all the additional Refineries mentioned in Table-2 above, the total LNG i.e. required to displace liquid naphtha as feedstock in the Hydrogen Plant of the Refineries computes to 4200 KTPA. In a way, it implies that the LNG saved by not setting up an Ammonia Plants for production of Urea, the same could be effectively diverted to all these Refineries to displace liquid feedstock.

A brief analysis reveals that the displaced naphtha from the Hydrogen Plant itself from the 15 Refineries listed above, would compute to 5200 KTPA. This quantum of naphtha itself is good enough to support world scale size Petrochemical Complex, though of course, it may not be realistic to actually assume that all the naphtha displaced from these Refineries could be centrally pooled. The transportation cost for the same would be significantly high. Nevertheless, very significant quantum of naphtha would be available in close proximity of certain Refineries, which can be clustered and supplemented with other feedstock to support huge Petrochemical facility. This way not only, tremendous amount of carbon recycling and optimization would take place, but also, a very significant Petrochemical capacity could be added in the country with significant feedstock available capacity without incremental imports. This would also be truly reflective of the Make in India concept, which the Hon’ble Prime Minister has been propagating. And that too, without any additional crude imports! The additional revenue that would result out of this Petrochemical Integration production would serve the economy in a big way. This will apparently provide a techno economic solution to the country’s major import reduction intent as well.

The CO2 foot print reduction by way of utilization of huge quantities of CO2 produced from the Refineries would be an added benefit, thereby serving as a major environmental objective. From the facilities as mentioned above, an effective CO2 reduction would be to the tune of 5 Million tons per annum.

Polycarbonates Case Study -Part 2 Futuristic

From the list of various Refineries mentioned above, the land locked Refineries may be identified as below:

For the above plants considering that Barauni Refinery is relatively small and currently there are plans of setting up a Fertilizer Complex the CO2 produced from the same, for the moment, is not being considered for chemical upgradation. The other four plants viz. HMEL, Panipat, BORL & Mathura however, are being looked into for Poly Carbonate facilities. For the purposes of the study and given the fact that Poly Carbonate is an industry which is yet to develop and its potential in terms of utilization is a matter of detailed study. Only 25% of the CO2 potential available from these Refineries is being considered for production of Poly Carbonates. Balance of the Refineries and the effective capacities of the Plant may be considered as below:

From the literature available, it is observed that the balance of plant with CO2 consumption as 8.7 T/hr, PO consumption of 6.6 T/hr, the effective PPC production is to the tune of 13.7 TPH and PC to the tune of 0.8 TPH. These figures have been pro-rated for the standard 15 TPH plant and effective utilization of CO2 , PO and PPC are as below:

The price range of PC and PPC is to the tune of Rs.1,10,000/T and Rs.1,50,000/T which are extremely attractive. The capex for 260 KTPA Plant of PPC + PC is to the tune of Rs.200-220 crores. Brief economics for the above Plants suggests that about Rs.1300 crores of investment would be required for the 4 Plants envisaged above at HMEL, Panipat, BORL and Mathura with Panipat supporting 2 chains of 260 KTPA. The operating margin to the tune of Rs.300 crores per annum can be anticipated from all these Plants together. These numbers are of course, tentative and subject to updation based on the order of magnitude estimates as well as, the revenue calculations based on the actual price trends of PC and PPC. Nevertheless, the indicative direction is that poly carbonates in small useful capacities is perhaps, a way forward. For the four facilities mentioned above about 2.6 Million Tonne of carbon dioxide consumption can be foreseen. This is also quite substantial and since the carbon dioxide is expected to be available between 20-22 Kg/Cm2 g pressure, the additional transition cost of raising the pressure to 70 to 80 bars would be relatively low.

As time passes and most of the Polycarbonate and other solutions through Utilisation of CO2 becomes more and more evident and feasible, a policy frame work to provide the right kind of environment and incentives for encouraging the same will have to come into force. In the interim it would be worthwhile to once again look into carbon credits and similar such schemes to try and mitigate the increment of the CO2 intensity across the globe.

One of the possible ways to look into the incentive for the future would be consider that the carbon content in the poly-ethylene and polypropylene is to the tune of 85 %. The world production of the ethylene and propylene as of now is to the tune of 250 MMTPA which is steadily on the increase. It implies therefore that if the carbon content of these were to be supplied by CO2 it would require CO2 to the tune of 780 GTons. Therefore, even a percentage of the total conversion of ethylene and propylene, utilising Co2 as a raw material would be a huge CO2 mitigating factor. Of course the right sort of environment and the Technology for the same will have to exist to bring this about. From a futuristic glass prism this certainly does not seem to be an unusual and unrealistic assumption to make given the current trends of research.   

A brief Co2 Utilisation quantum may be assessed from the following

Conclusion

From the above, it may be summarised that CO2 abatement remains a challenge and a combination of capture and utilization in the times to come, perhaps only would be a solution. Broadly, the carbon dioxide abatement from Power Plants would have to find way into capture and storage solution, if the transportation cost work out to be reasonable or desulphurization with CO2 recycle to form lime can perhaps work out as a viable option, it would be a solution.

On the utilization side, gasification interlinked with fertilizer, chemical production or synthetic gas production allowing with power could possibly be an economical route with value addition remaining under focus in the complete chain i.e. Methanol and/or DME as produce to lead to naphtha displacement from the gasoline pools, which in turn could be utilized to support a Petrochemical Complex. While Urea and DME remain a by-products DME blending into diesel and LPG pool could also supplement the Petrochemical Complex with LPG as feedstock.

Conversion of CO2 in presence of epoxide such as Propylene Oxide leading to production of poly carbonates and propylene poly carbonates for part consumption and recharge for industrial use can also be a parallel route through which CO2 abatement could be addressed.

In conclusion however, no single mode of solution seems to be a way out. It apparently, needs to be a combination of all the solutions for a winning solution to emerge with respect to carbon dioxide.