Government approves pricing formula for bio-ethanol procurement
Approval of the pricing formula for procurement of bio-ethanol is suggested by the Expert Committee, coupled with a floor price and a ceiling price
The Cabinet Committee on Economic Affairs has approved the pricing for bio-ethanol procurement by Oil Marketing Companies (OMCs) for Ethanol Blended Petrol (EBP) Programme as per the following:
(i) The 5% mandatory ethanol blending with petrol as already decided by the CCEA in the past, should be implemented across the country, for which the Ministry of Petroleum & Natural Gas will immediately issue a gazette notification, for the OMCs to implement from the 2012-13 sugar season, effective from 1st December, 2012.
(ii) Procurement price of ethanol will be decided henceforth between OMCs and suppliers of ethanol. (iii) In case of any shortfall in domestic supply, the OMCs and Chemical companies are free to import ethanol. It is expected that 5% bio-ethanol will be blended with petrol sold in all the States/ UTs across the country.
The EBP Programme is presently being implemented in a total of 13 States with blending level of about 2% against a mandatory target of 5%.
A stable EBP Programme would ensure sustainable benefits for sugarcane farmers across the nation.
It will ensure an alternative market for the farmers who frequently get adversely affected in case of bumper crop of sugarcane and lack of its demand in the market.
It will also provide an incentive to small and medium farmers to increase efforts towards sugarcane crop as better returns would be ensured.
Procurement of ethanol at a price determined by the market will ensure stability.
EBP programme not only provides opportunities to sugarcane farmers, but also ensures the use of ethanol as bio-fuel in a big way, which is environment friendly.
Besides, the extent of implementation reduces the dependence on imported crude and leads the nation ahead on fuel self sufficiency.
ETHANOL (Anhydrous Alcohol)
1. Relative Density at 15.6 deg C - Max.0.7961
2. Ethanol content at 15.6 deg C % v/v -Min. 99.80
3. Miscibility with water - Miscible
4. Alkalinity ppm - Nil
5. Acidity (CH3COOH) ppm Max.- 30
6. Residue on evaporation percent by mass ppm - Min. 50
7. Aldehyde (as CH3CHO) ppm - Max. 60
8. Copper ppm - Max. 1
9. Lead, as Pb ppm - Max. 1
10. Appearance - clear
The CCEA, in its meeting held on 16th August 2010, had approved the ad-hoc price of Rs. 27.00 per litre for bio-ethanol for procurement by OMCs.
This price was subject to adjustment on the basis of recommendation of an expert committee for pricing of ethanol. Later an Expert Committee headed by Dr. Saumitra Chaudhury, Member, Planning Commission, considered the issue of pricing of ethanol.
In its report, submitted in March 2011, the expert committee recommended a formula, which was derived broadly from the price of motor spirit.
Subsequently, a report by the Economic Advisory Council to the Prime Minister, submitted on 10.03.2011, recommended the fixation of price of bio-ethanol through the market mechanism. The issue of procurement price for bio-ethanol has been considered by a Group of Ministers and the CCEA.
The distillery plant is based on technologies of Continuous/fed-batch fermentation process with multi-pressure distillation to produce Rectified spirit (RS), Extra Neutral Alcohol (ENA) and Molecular Sieve Dehydration (MSDH) system to produce anhydrous ethanol.
The distillery and MSDH plants were supplied by DistiChemkiirocess Engineering Pvt. Ltd., Mumbai, Maharashtra. Fermentation, MPR distillation and Molecular Sieve Dehydration technologies installed by SSOPL are energy efficient processes capable of producing R.S. and fuel ethanol. Required quantity of molasses for alcohol production and rice husk for incineration boiler are purchased from nearby sugar mills and farmers, respectively.
For treatment and disposal of spent wash and for achieving “Zero Liquid Discharge (ZLD)” as per directions of CPCB/BSPCB, the SSOPL has installed integrated spent wash evaporation as a primary effluent treatment system followed by standalone evaporation plant as a secondary effluent treatment system followed by spent wash incineration as a final effluent treatment system. As per directions of CPCB, the Vasantdada Sugar Institute, Pune, has already prepared Adequacy Assessment Report of distillery ETPs and Up-gradation Plan of Effluent Treatment Plants In August 2017. The CPCB has directed Vasantdada Sugar Institute (VSI), Pune, to validate Adequacy Assessment Report of distillery ETPs submitted to CPCB during actual operation of the plant.
Accordingly, a team comprising of Mr R V Godage, Scientist and Mr R S Patil, Asst. Technical Officer of the Department of Alcohol Technology and Biofuels, visited the SSOPL distillery and effluent treatment plants from 3rd to 5th July, 2018 for validation of Adequacy Assessment Report of the distillery ETPs.
The distillery and effluent treatment plants were in operation during the visit of VSI team.
The distillery plant was in operation in fermented wash to ethanol mode. The technical team of VSI had detailed discussions With Mr Kishan Prakash Sharma. General Manager, Mr Atul Chaudhary, Production Manager and other technical staff of the distillery about the performance of distillery and effluent treatment plants during the current season. During the visit, operations & performance of each unit were verified and discussed with the technical staff of the distillery. Visits were made to the molasses storage faculty, molasses handling section, yeast propagation section, fermentation, distillation, integrated evaporation section, standalone multiple effect evaporation plant, incineration boiler and condensate polishing unit site jointly by the VSI team and technical staff of the distillery plant.
During the visit and inspection of various sections, observations on various process problems, operations and performance of each unit were made and jointly discussed with the technical staff.
The dlstillery plant details are as follows:
Year of commissioning: 2013, License capacity of distillery: 13.500 KL/annum, Distillery plant capacity: 45 KLPD (now enhanced to 75 KLPD), Name of supplier: DiStiChemi Process Engineering Pvt. Ltd. Mumbai. Fermentation Technology: Cascade continuous/Fed-batch Distillation Technology: Multi pressure to produce R. S. or ENA Fuel Ethanol Plant. 45 KLPD (Molecular sieve dehydration technology) Steam is supplied for distillation and evaporation plant from the spent wash incineration boiler of capacity of 20 TPH (@ 45 Kg/cm2 pressure.
Power is supplied from distillery TG set of capacity of 2 MW/hr. Fuel used for boiler is spent wash with supplementary fuel rice husk.
The alcohol % (vlv) in fermented broth observed during the VSI team’s visit was 10.25 to 10.50%.
Based on alcohol % in fermented wash, the spent wash generation of about 8.85 Lit./lLit. of alcohol produced seems to be realistic. The average of molasses distilled, alcohol production and raw spent wash generation during one month prior to the visit to distillery plant is given in table no. 2.0.
Table no. 2.0: Average of alcohol production & spent wash generation during one month (June 2018) prior to visit. 2. Primary Effluent Treatment system-Integrated evaporation plant (IMEE):- SSOPL has installed an integrated evaporation plant along with distillery.
In integrated evaporation plant, the spent wash generation is reduced by using distillation section heat energy (alcohol vapors) instead of steam.
Spent wash is generated from analyzer column with 14% solids, which is fed to integrated evaporation plant and concentrated up to 340 to 400 M3/day of 18% solids.
The SSOPL has achieved high alcohol concentration in fermented wash and raw spent wash concentration has about 18% solids.
Therefore, the SSOPL is not operating IMEE plant. 3. Secondary Effluent Treatment system Standalone Multiple effect spent wash evaporation plant (SMEE): The outlet spent wash of around 350 to 400 M3/day at 18% solids from distillation plant is fed to the standalone SMEE plant feed tank. Standalone spent wash evaporation plant is based on forced circulation type (five effects) and finisher (one effect) to concentrate the spent wash from 18% solids to 60% solids. As per the evaporation plant log book, the final brix is ranging between 52 to 56 °brix. The SMEE plant requires around 130 140 MT/day of steam at 1.5 kg/cm2 pressure. The SMEE plant details are as given below
Name of SMEE plant supplier: DistiChemi Process Engineering Pvt. Ltd. Mumbai, SMEE plant commissioning year: 2013. Plant & Machinery: Evaporators (6 Nos.), pre-heaters, VLS, surface condenser, tanks, instrumentations, pumps & motors, safety devices, MCC, etc. Flow meters for SMEE feed, process condensate, concentrated spent wash and steam. MOC of SMEE plant: SS-304
The SMEE plant installed by SSOPL is found to be of advanced technology and energy efficient. The characteristic of raw spent wash is given in table 3.0. Performance parameters for Standalone Multiple Effect spent wash evaporation plant (SMEE) . The data was collected from the log books in the SMEE plant and after discussion with the technical staff.
The overall performance of the SMEE plant is given in table 4.0 Table no. 4.0: Overall performance of the SMEE plant Steam economy achieved by SSOPL. Distillery is 1.95 kg water evaporation per kg steam used and the frequency of cleaning is every 10-12 days.
The cleaning of SMEE and incineration boiler is completed in about 3 days. The process condensate 245.48 M3/day was sent to condensate polishing unit for further treatment.
4. Tertiary Effluent Treatment system Incineration of concentrated spent wash in Incineration Boiler The SSOPL has installed 20MT/hr capacity, 45 Kg/cm2 (9) working pressure, FBC type incineration boiler using conc. slop as main fuel and rice husk as supplementary fuel.
The incineration boiler was installed in the year 2013.
The incineration boiler was supplied by Cheema Boilers Ltd; Mohali, Chandigarh, Punjab.
Main furnace for incineration of slop and rice husk is fluidized bed. Furnace temperature is maintained in the range of 760°C to 770°C Conc.
Slop is fired in furnace with four spray guns.
Wet scrubbing system is installed for removal and cooling of ash discharged from flue gas passage and furnace.
The designed parameters of incineration boiler are given in table no.5.
Steam at 44-45 Kg/Cm2(g) Supplied to 2 MW, 3.5 Kg/cm2(g) back pressure turbine.
The exhaust steam is used for distillation, MSDH plant operation and evaporation of spent wash.
The power generated is sufficient to operate distillery, SMEE, CPU and boiler.
Cleaning frequency is once in every 12 days. Fouling on pressure parts and flue gas passage is removed by moderate pressure water jet.
Fouling of super-heater tubes is very less due to use of rice husk in the super-heater furnace.
The average ash generation is in the range of 25-30 MT/day. The ash generated after wet scrubbing is disposed off for land filling, making fertilizers and bricks manufacturing. The Standard Particulate Matter emission from the stack is observed between 50 to 70 mg/NM3 and is within permissible limits.
Boiler log book and test report of monitoring stack emission, monitoring of ambient air quality & monitoring of ambient noise level (day time) within plant premises are enclosed. 5. Condensate Polishing Unit (CPU) The SSOPL has installed CPU of capacity 600 M3/day in the year 2013 and supplied by DistiChemi Process Engineering P. Ltd. Mumbai.
The type of CPU is conventional i.e. anaerobic followed by aerobic followed by clarifier.
During the team’s visit, it was found that this CPU was not in operation. The SSOPL installed a new CPU (RO plant – I & II) in 2018 for treatment of process condensate, spent lees and other streams of water. It was observed that the treated water (Permeate) is used for cooling tower make-up & dilution of molasses in fermentation section.
It was also observed that the reject of CPU is used for boiler ash quenching and gardening.
During visit the RO-I was in operation and RO-II was under maintenance. CPU permeate recovery - 86% Permeate water used for cooling tower - 300 M3/day Permeate water used for Molasses dilution - 148.98 M3/day Detailed analysis report of untreated, treated & reject process condensate sample is enclosed.
6. Details of utilities (Water, Steam & Power) consumption: Based on the discussion with technical staff of SSOPL and the data collected, the water balance considering fresh water consumption and recycled streams is given in table no. 7. Steam & power consumption for distillery, evaporation, incineration boiler & auxiliaries and CPU are given in table no. 9.
Online monitoring system: The onIine monitoring system has been installed, commissioned and connected to the CPCB and BSPCB servers.
The details of online monitoring system are given in table no. 9. Five Pizometers with DWLR (Digital water level recorder) are installed in the distillery premises.
Rain water harvesting program has been implemented by the SSOPL.
As per CPCB guidelines, the distillery has installed Mass flow meters instead of Magnetic volumetric flow meter. Enclosed herewith are annexure I to XIV of Environment Clearance, Consent to Operate, Discharge consent order, Emission consent order, Ground water withdrawal order, Excise License, Log book Xerox, online monitoring reports & test reports.
i) Fermentation process is operated in fed-batch mode. The average alcohol concentration in fermented wash was in the range of 10.25-10.50% v/v. Due to high alcohol concentration in wash, there is reduction in water required for molasses dilution, reduction in steam requirement for distillation and also reduction in spent wash generation per litre of alcohol production.
ii) In fermentation section, for post clarification the SSOPL has installed 2 decanters for sludge separation. The separated sludge is dried in impervious sludge drying beds. The dried sludge is used for agriculture manure.
iii) As per previous visit in August 2017 for Adequacy Assessment report, the plant was operating at more than 45 KLPD capacity.
At that time, the VSI recommended that SSOPL should not produce more than 45 KLPD spirit as per license capacity, because the effluent treatment system can handle only 45 KLPD distilleries spent wash. After capacity enhancement in 2019, SSOPL is now operating the distillery plant at enhanced capacity.
iv) Performance of SSOPL distillery effluent treatment plants was found satisfactory, considering the spent wash generation and available spent wash effluent treatment system (integrated evaporation followed by Standalone Multiple Effect raw spent wash evaporation followed by incineration of concentrated slop in slop cum rice husk fired boiler). It seems that the present effluent treatment system installed at SSOPL for treatment & disposal of spent wash is found satisfactory.
v) The 20 TPH slop cum rice husk fired boiler is adequate to burn the conc. wash with 60% TS. The incineration boiler runs for 12 days and then stopped for periodical cleaning for 2 to 3 days. Standard Particulate Emission from the stack is reported to be 50 mg/NM3 and is within prescribed limits.
vi) The process condensate, spent lees and other clear colorless effluents are treated in condensate polishing unit (R.O. base). Treated water, i.e. R.O. plant permeate, is used as cooling tower makeup water and for molasses dilution. The R.O. plant reject is used for boiler ash quenching and gardening.
vii) The R.O. reject has very high organic and inorganic load. Therefore, SSOPL should not use the R.O. reject directly for boiler ash quenching and gardening. It should be recycled to SMEE feed tank.
viii) The storage of spent wash impervious tank level should be maintained by SSOPL as per capacity. During the visit, it was observed that the spent wash in the spent wash storage tank was filled to almost 100% level.
ix) Online monitoring system is operational & connected to the servers of BSPCB and CPCB and working satisfactorily. As per CPCB guidelines, the SSOPL has installed mass flow meters Instead of volumetric magnetic flow meters.
x) During the visit, we have also inspected the surrounding area for evidence of discharge of spent wash, particularly the area near impervious spent wash storage tank and adjacent Nala. However, we have found the area near impervious spent wash storage tank and adjacent Nala dry.
11. Suggestions for up-gradation: For standalone evaporation plant, it is necessary to install standby evaporator bodies each for falling mm and forced circulation. Boiler ash needs to be analyzed regularly to explore the possibility of its applications for other purposes for value addition.
It is also advisable to take proper care of green belt surrounding the spent wash storage tank.