World’s first “Carbon Capture and Sequestration” (CCS) plant integrated with Solar Thermal Technologies has been Installed at RKDF Unity in Bhopal and Gujarat based Sunrise CSP designed, manufactured and supplied the same.
It’s now accepted fact that “Carbon Emissions” from burning of fossil fuels lead to Global warming. World over government and scientists are working on policy and finding solutions to combat global warming and climate change. Its consequences are being felt world over leading to loss of Lives and Property. India too has been leading in its efforts and our Prime Minister Shri Narendra Modi in “Paris COP Meet” has committed that India will retrofit five of its coal fired power plant of 500 MW each with Carbon Capture & Sequestration (CCS).
A small pilot plant was developed and installed by Prof V K Sethi while he was working at RGPV in Bhopal. It was a proof-of-concept project where a System was built to scrub 1 kg/hr co2 from flue gas.
The present project is further extension to scale up the CCS technology. Central Power Research Institute (CPRI) based in Bangalore sanctioned this larger project to show and demonstrate its working. Prof V K Sethi who had shifted to RKDF as Vice Chancellor, accepted the assignment as Principal Investigator (PI) with Dr Sunil Kumar Gupta VC of RGPV was the co-investigator in this project.
After tendering Gujarat based Solar Concentrating Company Sunrise CSP India Pvt. Ltd was selected. In my earlier blog I have already covered Sunrise CSP India Pvt. Ltd. In which my Mentor Deepak Gadhia is the Chairman. It is bringing to India a game changing BIGDISH Concentrator of 520 m2 and the installation of the BIGDISH is going on in full swing at Muni Seva Ashram (The Green Ashram) , Goraj, Vadodara.
Since there was budget limit, it was decided to go for the CCS system. It is designed to tap-off 250 kgs/hr flue gas from Stack of the chimneys of coal fired power plant. Co2 content in the coal fired flue gas is about 18 % and thus the system is to remove 45 kg/hr co2 from the flue gas and recovered for potential use.
One of the major impediments to use and spread of CCS Technology till date has been that part of the Energy produced by Power Plant had to be used to release the co2 absorbed in MEA Solution and thus seen as Energy Penalty.
To overcome the problem of Energy Penalty it was decided to integrate Solar Thermal System to generate the steam needed for releasing the Co2 absorbed in MEA Solution.
Sunrise offered to undertake the Project on turn-key basis i.e. not only supply Solar Concentrators for thermal energy for generating steam but also design, manufacture, supply install and testing the complete CCS System and integrate the system with the Solar Thermal Concentrators.
RKDF Uni accepted the proposal after floating tender and scrutinizing the cost competitiveness and technical competence of Sunrise CSP India’s team.
It was decided to first install and test the system in RKDF University campus and once tested shift it to any pulverized coal fired power plant.
Thus the CCS integrated with Solar Concentrator has been installed in premises of RKDF Uni, Bhopal and the project was completed on 1st March 2021 and handed over.
One month of data collected and evaluated has proved that the system has performed as offered and has efficiency above 84 % of CO2 capture and recovery. It was decided to launch the system by inaugurating the same at the hands of Minister of Higher Education of State of Madhya Pradesh Dr. Mohan Yadav on 3rd March 2021
Working of Carbon Capture System. (CCS):
The Schematic below depicts the Process of CCS with Solar thermal.
The Process :
- 250 kg/hr of flue gas is generated at RKDF in coal fired boiler. It is first sent in/ over ash collection tank and the ash is removed from the flue gases. Just before the inlet where the flue gas enters the ash removal system, a CO2 analyser collects the sample and measures the amount of CO2 entering the cyclone separator.
- The cyclone separator removes the moisture and remaining dust particle from the flue gas with the centrifugal force effect.
- The flue gases are than sent to Na2CO3 scrubber tower with the help of blower, which provide sufficient pressure to flue gas so that the flue gases passes smoothly through the scrubber tower.
- There are two Na2CO3 scrubber tower and the function of the Na2co3 scrubber is use to remove the Sox and NOx present in the flue gas. Flue gas is let into the scrubber tower from the bottom and from the Na2CO3 solution is sprayed from the top of the Scrubber. The Na2co3 solution is appropriately pressurized by the pump to enable proper chemical reaction. To improve the absorption efficiency the tower is packed with packing known as Paul Ring. They maximize the surface area and increases the residence time for complete reaction to take place. This process is repeated in second Scrubbing tower so that complete and Sox and NOx is removed. Removal of Sox and Nox from Flue increases the life cycle of MEA Solution.
- In next step the flue gas passes through the third scrubber in which the MEA Solution absorbs the CO2 from the flue gas and the rest gases in flue such as Nitrogen and Oxygen are released into the atmosphere. The duration for the MEA Solutions to get staturated by absorbing Co2 is about 16 hours.
- The saturated MEA is then transferred to an intermediate storage tank.
- The saturated solution MEA from the intermediate tank is transferred to reactor. The reactor has an outer jacket through which steam is circulated to heat the MEA Solution. There is also an inner pipe coil immersed in the MEA Solution to cook the MEA when needed. The steam is generated with Solar Concentrators called Scheffler Concentrators. As back-up boiler is used. The reactor also has a stirrer to continuously mix the MEA Solution to maintain the constant temperature inside the reactor.
- When reactor temperature reaches 130 degree C the CO2 starts to release. The maximum CO2 is absorbed at 165 degree C. During this release of CO2 the water vapour and MEA start evaporating.
- To recover the evaporated water a water-cooled condenser is used, and CO2 remains in gases state.
- It is planned to use the CO2 for the production of hydrogen, methane, bio-diesel, Solid CO2 (dry ice). CO2 can also be filled into gas cylinders and used for welding. It can also be converted into food grade CO2 for its use in the beverage industries for manufactured aerated drinks.
Way forward for Solar Thermal Sector ….
In India, the main drivers for solar thermal are the GEF-UNDP programme for concentrating solar thermal (CST) market development, and the GEF-UNIDO programme for solar thermal industrial process heat. While GEF-UNDP achieved 44,949 m² of CST market, GEF-UNIDO is progressing with an additional 45,000 m² installed area of CST systems. As an incentive, the Indian Renewable Energy Development Agency (IREDA) offers a 5%-interest loan. This scheme is also extended to manufacturing now, which makes this the first instance of any incentive for the solar thermal manufacturing industry ever announced.
MNRE has estimated the potential of solar thermal collectors to be about 140 million m². The Government of India wants to install 175 GW of renewable energy for power generation and an estimated 20.13 million m² installed area of solar thermal collectors by the year 2022.
The National Solar Mission (NSM), which was announced in January 2010, was a turning point for the solar thermal market development with targets of cumulative solar thermal area of 20 million m² and is spread over three phases:
- Phase 1 : 2010 – 2013 – 7 million m²
- Phase 2 : 2013 – 2017 – 15 million m²
- Phase 3 : 2017 – 2022 – 20 million m²
So What’s Stopping & holding back the adoption of Solar Thermal in India !
- May be a Policy that makes it mandatory for industries to meet a certain percentage of heat through solar collectors ! as what is prevailing in Solar PV currently in many states.
- Massive Lack of awareness amongst bankers and financial institutions about the performance solar concentrators, which drastically impairs their ability to finance projects and provide working capital.
While government is helpful in announcing the solar policies but the bureaucracy is exhausting.
However, I am sure the solar thermal technology has great potential to re-start a new Era for Solar Thermal applications specially in heating, cooling and Power in India !
Meanwhile, please #StaySafe #StayHome & #StayHealthy
And till we meet next time with more updates… !
Solar Project Consultant – India