TRI-CONTROL TRI-JACK WWW.ZWICK-VALVES.COM
Process Engineering and Optimization
electricity, producing CaC2 along with carbon monoxide, which can subsequently be converted into chemicals via the syngas route (see FIG. 2 in Part 1).28
While this method is expected to reduce energy consump-tion, the development of such technology for Indian low-grade coal is needed, along with due analysis of the accompanying techno-economic aspects. Similarly, coal pyrolysis in hydrogen in a thermal plasma reactor provides a direct and cleaner route to acetylene production, bypassing the energy-intensive car-bide step. This results in no direct CO2 emissions and avoids the requirement of large amounts of water.
A 5-MW arc reactor has been developed in China that dem-onstrates total energy cost savings of about 25%, a CO2 emis-sions reduction of about 50%, a water requirement reduction of about 60%, and coal savings of about 40% in comparison with the conventional calcium-carbide method.26
Also, the traditional fixed-bed reactors for VCM production from acetylene are replaced by fluidized bed reactors, which allow for better control of temperature, increased VCM con-version rate (≥ 99 %), reduced mercury catalyst sublimation, decreased equipment and catalyst costs, and dramatically in-creased production capacity.18
These developments suggest that new-generation technol-ogies can have a significant impact on the cost of coal-based chemicals compared to the traditional calcium-carbide route.
India should explore and exploit these upcoming technologies to its advantage.
Conclusions. The comparative cost analysis herein suggests that manufacturing fit-for-purpose quantities of coal-based PVC can be an economically viable option, especially in high-oil-price scenarios. This will also help to avoid the high CAPEX require-ments and associated project risks of large cracker complexes.
Moreover, since the existing process is largely reliant on vin-tage technologies, it provides opportunities to implement mod-ern technological advances and gives further scope for applying energy-efficient techniques to curtail production costs, poten-tially further reducing breakeven costs.
The fit-for-purpose scale of such plants is apt for decentral-ized production near coal mining belts, with consequent ben-efits to local communities. Moreover, while the feasibility for PVC from coal is illustrated, analogous analyses may be carried out for other ethylene-based chemicals, especially for relatively low-volume ethylene derivatives. The authors believe that the above aspects will make many coal-based chemicals alluring, particularly from the Indian perspective.
These advances could make India self-sufficient, curtail its dollar-based imports, bolster a “made-in-India”-tagged chemical industry, and justify strategic investment in these alternatives to meet the long-term objectives of energy import independence.
The Indian industrial and scientific communities should ex-plore and exploit developments in the carbide world, as well as newer processes for producing acetylene directly (which avoid the carbide step altogether). Recent remarks by the India’s sec-retary of the Department of Chemicals and Petrochemicals on
Select 161 at www.HydrocarbonProcessing.com/RS
Process Engineering and Optimization
the potential of coal-based chemicals in India29 acknowledge the need to substitute petroleum feedstocks with coal.
End of series. Part 1 of this article appeared in April 2016.
LITERATURE CITED
1 IHS, “Outlook for olefins and polyolefins…and the great energy price deflation,” 2015.
2 Deutsche Bank, “China’s coal to olefins Industry,” 2014.
3 US Environmental Information Administration (EIA), “Short-term energy outlook”
and “Annual energy outlook,” 2015.
4 World Bank, “World Bank commodities forecast,” 2016.
5 BNEF, “Is the US chemicals renaissance a flash in the pan?” 2014.
6 US EIA, “Technically recoverable shale oil and shale gas resources: An assessment of 137 shale formations in 41 countries outside the US,” 2013.
7 Mukherji, B. and S. Chaturvedi, “Why India can’t unlock its shale gas,” Wall Street Journal, June 11, 2011, online: http://blogs.wsj.com/indiarealtime/2013/06/11/
why-india-cant-unlock-its-shale-gas/
8 IEA Clean Coal Center, “Techno-economics of modern pre-drying technologies for lignite-fired power plants,” 2014.
9 IEA Clean Coal Center, “Utilisation of low rank coals,” 2011.
10 IEA Clean Coal Center, “Coal upgrading,” 2009.
11 Kumar, V., C. Banerjee, P. K. Biswas, “Optimization of solvent extraction process parameters of Indian coal,” Mineral Processing & Extractive Metall. Rev., Vol. 33, 2012.
12 Sharma, D. K. and S. Gihar, “Chemical cleaning of low grade coals through alkali-acid leaching employing mild conditions under ambient pressure,” Fuel, Vol. 70, 1991.
13 Li., G., Q. Liu and Z. Liu, “CaC2 production from pulverized coke and CaO at low temperatures—reaction mechanisms,” Ind. Eng. Chem. Res., Vol. 51, 2012.
14 Paessler, P. et. al, “Acetylene,” Ullmann’s Encyclopedia of Industrial Chemistry, 2012.
15 Schobert, H., “Production of acetylene and acetylene-based chemicals from coal,”
Chemical Reviews, Vol. 114, 2014.
16 Corones, M., “Is coal’s decline permanent?” Reuters, January 6, 2015, online:
http://blogs.reuters.com/data-dive/2015/01/06/is-coals-decline-permanent/
17 Hoyle, R., “As coal prices fall, miners cut output,” Wall Street Journal, June 2, 2015,
online: http://www.wsj.com/articles/as-coal-prices-fall-miners-cut-output- 1433269071
18 China’s Ministry of Environmental Protection, “Project report on the reduction of mercury use and emission in carbide PVC production,” 2010.
19 UNEP, “Vinyl chloride monomer production,” online: http://www.unep.org /chemicalsandwaste/Mercury/PrioritiesforAction/VinylChlorideMonomer Production/tabid/4523/Default.aspx
Complete literature cited available at HydrocarbonProcessing.com
MAHESH MARVE is chief technology officer (CTO) and senior vice president at Tata Consulting Engineers (TCE) Ltd. He has a chemical engineering degree from ICT in Mumbai, India, with 25 years of extensive experience in refining, petrochemicals and technology management. Prior to joining TCE, he worked for Reliance Industries for 24 years. His last role at Reliance was chief of advanced technical services for Reliance’s Jamnagar refinery. He was instrumental in a significant debottlenecking of the original refinery and played a key role in concept-to-commissioning work of the second refinery at Jamnagar.
S. SAKTHIVEL has been senior technologist at Tata Consulting Engineers Ltd. since 2009. He holds a BTech degree, an MTech degree and a PhD from the University of Madras, Anna University and the Indian Institute of Technology Delhi, respectively. Dr. Sakthivel has experience in chemical processes, nano and particle technology, and biofuel energy. He is the author of 12 articles in peer-reviewed journals.
PARESH V. PALUSKAR is a senior technologist at Tata Consulting Engineers Ltd. He completed his PhD in physics from Eindhoven University of Technology in the Netherlands in 2008, and his MSc in sensor systems technology from FH-Karlsruhe in Germany in 2003. Dr. Paluskar has been working with Tata Consulting Engineers since 2009 in the field of renewable and sustainable energy.
Process Engineering and Optimization
H. DE PAZ CARMONA and A. BRITO ALAYÓN, University of La Laguna, Santa Cruz de Tenerife, Spain; M. ROMERO VÁZQUEZ and J. FRONTELA DELGADO, Cepsa Research Center, Alcala de Henares, Spain; J. J. MACÍAS HERNÁNDEZ, Cepsa, Santa Cruz de Tenerife, Spain