Green Blends

In order to reduce the dependency on crude oil import and save its foreign exchange reserves, the government announced the Ethanol-Blending Programme (EBP) on September 4, 2002. Initially, the programme mandated the blending of 5 per cent ethanol in petrol, which was revised upwards to 10 per cent on January 2, 2013. However, only 3.2-4 per cent ethanol blending could be achieved during 2015-17. The centre has now set an ambitious target of 10 per cent ethanol blending in petrol by 2022.

Ethanol is produced in India mainly from molasses and foodgrains. However, of the total ethanol produced, only one-third is available for EBP, while the rest is consumed by the liquor and chemical industries. First-generation biofuels are made from the sugar and vegetable oils found in food crops using standard processing technologies. Second-generation (2G) biofuels, also known as advanced biofuels, are fuels that can be manufactured from various types of non-food biomass such as plant materials and animal waste. The government is encouraging the production of 2G ethanol from agricultural residue to provide an additional source of income to farmers, address the growing environmental concerns and support the EBP.

New alternatives/ventures

HPCL Biofuels Limited (HBL) was incorporated in October 2009 as a wholly owned subsidiary of Hindustan Petroleum Corporation Limited (HPCL) to set up integrated sugar, ethanol and cogeneration power plants by reviving two closed sugar mills in the state of Bihar.

In December 2007, when the Bihar government invited requests for qualification (RfQs) for 15 closed sugar mills owned by Bihar State Sugarcane Corporation Limited, HPCL participated in the bids for four sugar mills. The company emerged as the highest bidder for two sugar mills – one at Sugauli in East Champaran district and the other at Lauriya in West Champaran.

HPCL acquired the defunct mills from the the Bihar State Sugar Corporation in 2009-10 and formed HBL to handle this new venture. As the existing machinery in both mills was in a dilapidated condition and very outdated, it was sold as scrap, and modern state-of-the-art, integrated sugar, ethanol and cogeneration plants were set up with the following features:

  • Crushing capacity of 3,500 tonnes of cane per day (tcd).
  • Distillery plant with 60 kilolitres per day (klpd) of capacity.
  • 20 MW cogeneration plant (turbine generator) and a 110 tonne per hour steam generator.

Both integrated sugar plants were commissioned in December 2011 and have been operational since the 2011-12 season. The plants have state-of-the-art cane/ bagasse diffusion technologies with highly efficient and continuously operating boiling and sugar process houses for processing juice generated from 3,500 tcde cane crushing, to manufacture good quality white plantation sugar.

The cogeneration plants utilise the captively generated bagasse to produce steam and power. The surplus power so generated is exported to the Bihar state power grid, for which HBL has signed a power purchase agreement with the state power corporation.

Each distillery has a biocompost yard and a biodigester, and produces 60 klpd of fuel-grade ethanol. The biomethanation plant reduces the biological/chemical oxygen demand levels and generates biogas to be used as fuel in the cogeneration power plant boiler. The biocompost equipment is used to treat the spent wash generated from the ethanol plant, while ensuring zero effluent discharge, and the compost fertiliser thus produced is sold to the farmers in the command area. The company’s ethanol production is being sold to the HPCL, Bharat Petroleum Corporation Limited (BPCL) and Indian Oil Corporation Limited (IOCL) depots in the vicinity.

Environmental compliance

To ensure environmental compliance of the integrated sugar mill, distillery and cogeneration projects, the company has installed an effluent treatment plant (ETP) of 700 cubic metre per day capacity (for the sugar mill and cogeneration plant), multi-effect evaporators (MEEs) for the distillery unit and an electrostatic precipitator so that the treated effluent and stack emissions generated from the unit meet the norms stipulated by the Environmental Protection Agency and the Bihar State Pollution Control Board (BSPCB). In case of process disturbances or failure of the pollution control equipment, the respective unit will be shut down and will not be restarted until control measures are taken to achieve the desired efficiency.

HBL was the first company in Bihar to install an online effluent monitoring system in line with the Central Pollution Control Board (CPCB) direction issued on February 5, 2014. The details of the same were submitted to the CPCB/SPCB. Cameras and GPS-enabled flow meters were installed at the outlet, from where raw spent wash is generated, and at the inlet and outlet of the MEEs, along with a suspended particulate matter analyser in the chimney.

The units generate 180 cubic metres of spent wash per day, which, after biomethanation in the anaerobic digester, is concentrated in the MEEs and the concentrated spent wash is composted with press mud. The distillery operates for maximum 270 days in a year and cannot operate during the rainy season. The effluent from the sugar unit and cogeneration power plant, and the wastewater from washings of the distillery unit are treated in the ETP, which operates on the activated sludge process followed by extended aeration.

Acres of land have been earmarked for a biocomposting yard. Spent wash is stored in an impervious pucca lagoon with proper HDPE (high density polyethylene) lining, with a storage capacity of 30 days spent wash generation, to prevent groundwater pollution. Treated effluent from the sugar mill is recycled and re-utilised within the project premises for plantation, dust suppression and green belt development. Bagasse from the sugar mill is stored in a covered shed for further use as boiler fuel.

Sharing experiences

As per Rajeshkumar R. Chavada, chief operating officer, HBL, during the 2017-18 season, HBL’s sugar industries faced peculiar challenges, along with other mills in Bihar. The restrictions imposed on sugar sales by the government in its control order have severely impacted the cash flow of the industry, leading to storage issues.

Also, the stringent regulations imposed by the CPCB on sugar mills and distilleries in the Ganga basin have affected ethanol production. The major issue arising out of these is spent wash management.

At a business meet organised by the Cogeneration Association of India in Lucknow, in March 2018, an appropriate solution for spent wash management was proposed by ISGEC Heavy Engineering Limited, a major manufacturer of spent wash/slop-fired travelling grate boilers (incineration boilers). Also, user feedback on the same by Balrampur Chini Mills proved extremely useful for HBL.

Expansion plans

In December 2016, the Institute of Chemical Technology (ICT) signed MoUs with petroleum giants BPCL and HPCL for technology transfer and for building commercial-scale ethanol plants based entirely on the technology developed by the Department of Biotechnology (DBT)-ICT Centre for Energy Biosciences. These plants will be operational by the end of 2018.

BPCL is setting up a 2G biomass ethanol biorefinery in Bina, Madhya Pradesh, with a capacity to process 400 tonnes per day of biomass (equivalent to 100 klpd of ethanol generation capacity). The plant is expected to produce around 32,000 kl of ethanol per year. A 2G ethanol plant with 100 klpd capacity is proposed to be set up by HPCL in Bathinda, Punjab. The proposed plant is expected to utilise around 400 tonnes of agricultural residue per day or 128,000 tonnes of biomass as fuel to produce around 100 klpd of ethanol.

In May 2017, HPCL awarded a contract to Engineers India Limited, DBT and International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) for setting up the 2G ethanol biorefinery in Bathinda at a cost of Rs 6,000 million. The plant may use sugarcane, biomass and other agricultural residues like rice straw, wheat stubble and maize residue for the production of ethanol. It will help in reducing CO2 emissions from the paddy straw, burnt after harvesting. The biorefinery will also produce about 32,000 tonnes of bio-fertiliser per annum, which can be used as a soil nutrient. Apart from this, the plant will produce bio-CNG, which can be used as fuel for cooking and vehicles.

ICRISAT will conduct a viability study on various sources of ethanol in the state so as to reduce its dependence on one particular source. It is exploring sources other than sugarcane, such as other biomass, rice straw, wheat stubble and maize residue, along with their availability and viability for producing ethanol.

These projects are not without challenges though. In August 2016, due to lack of availability and commercial viability, the three oil marketing companies – IOCL, BPCL and HPCL – shut down the joint venture companies they had started for jatropha cultivation to manufacture biodiesel. As per experts, a jatropha tree takes seven to eight years to grow. Besides the long gestation period, there were assumptions that jatropha should be grown on barren land. Though the plants survived without water, they did not yield oil. The assumption that they would produce oil even without irrigation was misleading.

In conclusion, oil management companies have made commendable efforts to explore all avenues of ethanol production. It is hoped that all stakeholders will work together in a transparent manner to make these current projects a success, so that they could be replicated across the country to help reduce India’s petrol import bills.

(With inputs from HPCL Biofuels Limited, Patna)

By Anita Khuller

GET FREE ACCESS TO OUR ARTICLES

Enter your email address