REQUIREMENTS FOR AMENDMENT IN ENVIRONMENTAL CLEARANCE JUSTIFICATION FOR MODIFICATION IN THE SCHEME FOR SPENT WASH HANDLING IN THE DISTILLERY PLANT

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1 AMENDMENT IN ENVIRONMENTAL CLEARANCE GRANTED BY MINISTRY OF ENVONMENT AND FORESTS, NEW DELHI VIDE FILE NO. J-11011/773/2007 IA II (I) DATED 16 TH JANUARY, 2008 REQUIREMENTS FOR AMENDMENT IN ENVIRONMENTAL CLEARANCE 1. Modification in the scheme for spent wash handling in the distillery plant 2. Modification of APCD in the boilers 3. Utilization of ETP sludge, Yeast sludge in the incineration boiler with conc. and dried spent wash. 4. Inclusion of ENA as product alongwith Rectified Spirit/Export Quality Rectified Spirit/Special Denatured Spirit JUSTIFICATION FOR MODIFICATION IN THE SCHEME FOR SPENT WASH HANDLING IN THE DISTILLERY PLANT Khandoba Distilleries Ltd. are setting up a 150 KLPD molasses based distillery plant and 6 MW of Cogeneration Power Plant located at MIDC Tembhurni, Village Tembhurni, Taluka Madha, District Solapur, Maharastra. The industry has been granted Environmental Clearance by the MoEF. As per the EC granted to the industry, whole of the spent wash has to be handled by directly concentrating the spent wash in MEE and then incinerating the conc. spent wash into the incinerator boiler. The industry intends to modify the scheme for the treatment and handling of spent wash, to be generated by the industry. The proposed scheme for the spent wash treatment is as below; Anaerobic digestion of spent wash for methane gas recovery from the organics present in it Conc. of spent wash in MEE after methane gas recovery (Biomethanation) Drying of conc. spent wash in drier Pelletisation of dried spent wash and dewatered yeast and ETP sludge Burning of pellets in low pressure incineration boiler

2 Problems in direct conc. of spent wash in MEE and then incinerating the conc. spent wash into incinerator boiler 1. The molasses based distillery spent wash contains more than 35 % inorganic solids which are chiefly potassium oxide, calcium oxide and sodium oxide. 2. The spent wash contains around % of potassium oxide (on dry basis). 3. The vaporization temperature of potassium is 850 O C. Due to low vaporization temperature, the potassium salts present in the conc. spent wash vaporizes in the incinerator boiler furnace and travels alongwith the hot air in the boiler area. During the contact of the hot air with the boiler tubes, the potassium vapors start adhering to the boiler tubes from their outer surface. With regular adhesion, the scaling formation takes place on the outer surface of the boiler tubes and heat transfer efficiency of the boiler tubes reduces with every passing day. Every industry has to clean the boiler tubes regularly from its outer surface once in a month. The cleaning operation takes around 5-6 days and during this period, the plant has to be shut down. Benefits of the scheme proposed 1. Methane gas would be recovered from the spent wash through anaerobic digestion which is pure and clean source of energy. Methane gas would be used within the industry and would be burnt in the distillery plant boiler alongwith bagasse and other biomass as fuel. The methane gas would replace around % of fuel requirements for the CHP boiler. 2. After methane recovery in the anaerobic digestion, due to low organic contents present in the spent wash, the operation of MEE for concentration of spent wash would be more effective. The industry can concentrate the spent wash upto 70 % solid concentration. 3. Drying of conc. spent wash in a drier would be easy due to presence of low organic non fermentable sugars. 4. The industry would be able to use all the sludges generated from the plant for the production of fuel pellets by mixing dewatered sludge and dried spent wash. 5. Low pressure standalone incineration boiler would be installed with fuel pellets being used as fuel. Due to low temperature of the boiler furnace, the scaling problem of the potassium salt would be eliminated. JUSTIFICATION FOR MODIFICATION OF APCD IN THE BOILERS The industry would install 30 TPH capacity main plant boiler operating at upto 67 kg/m 2 working pressure with power cogeneration. The fuel for the boiler furnace would be bagasse/biomass, coal and methane to be generated from the anaerobic digestion of the spent wash. The industry would install Electrostatic Precipitator for the 30 TPH capacity main plant boiler. The industry would install 15 TPH capacity incineration boiler operating at upto 10 kg/m 2 working pressure. Due to low size of the boiler and effective recovery of boiler ash (to be used as fertilizer in the cane fields due to high potassium conc.), the industry intends to install Bag House Filter for the Incineration Boiler.

3 JUSTIFICATION FOR UTILISATION OF ETP SLUDGE, YEAST SLUDGE IN THE INCINERATION BOILER WITH CONC. AND DRIED SPENT WASH The ETP sludge and yeast sludge has organic contents present in it. In order to make the industry more hygienic and adopting sound environmental practices, the ETP sludge and yeast sludge would be dewatered using decanter. The dewatered sludge would be mixed with the dried spent wash for the production of fuel pellets. JUSTIFICATION FOR INCLUSION OF ENA AS PRODUCT ALONGWITH RECTIFIED SPIRIT/EXPORT QUALITY RECTIFIED SPIRIT/SPECIAL DENATURED SPIRIT The industry is installing molasses based distillery plant at the site. Presently, the industry would produce anhydrous alcohol for its utilization in the gasoline fuel. Since, the petroleum prices are moving southwards, there are chances of non-utilization of anhydrous alcohol in the gasoline fuel. For this reason, the industry intends that it should have the permission for the production of ENA as product for future. We request to MoEF to add the main product from the plant as ENA/Anhydrous Ethanol/RS/Export Quality RS/Denatured Spirit. The byproduct would be CO2 and incineration ash to be used as fertilizer.

4 Molasses (600) Spent Lees and MEE Condensate (600) Yeast Culturing and Fermentation (1790) 665 CO2 (120) Fresh Water (590) Steam (550) 1670 Multi-pressure Distillation (1670) Steam Condensate (550) Spent Wash (1220) Spent Lees (300) 1220 Alcohol (150) Anaerobic Digesters for methane recovery (1220) Biogas (107) Steam Condensate (250) Steam (250) Multi Effect Evap. For conc. of biomethanated spent wash (1220) Conc. Spent Wash (170) MEE Condensate (1050) Steam (50) Dryer for drying of conc. spent wash (170) Dried Spent Wash (130) Coal (45) Dewatered Yeast and ETP + digester Sludge (25) Pelletisation of dried spent wash, coal and Yeast and ETP Sludge (200) Pellets to Incineration Boiler (200) Figure : Idealized Mass Balance All values are in MT/day Khandoba Distilleries Ltd. Solapur (Maharastra)

5 Water Balance for Cooling Towers MEE Condensate (750) Fresh Water (450) Cooling Tower (1200) Evaporation Losses (1140) Blow Down to ETP (60) Balance for Misc. use Domestic Use (20) Domestic Eff. to ETP (18) Water for Softening (1000) Rejects to ETP (50) Ferm./floor washing (25) Wastewater to ETP (25) Water Balance for Treatment Ferm./floor washing (25) C. T. Blowdown (60) Domestic Effluent (18) ETP (183) Irrigation purposes (183) WTP Reject (50) Boiler Blow down (30) Khandoba Distilleries Ltd. Solapur (Maharastra)

6 CO2 (120) Composition of Molasses (600) Fermentable Sugars (270) Non Ferm. Sugars and other other organics (120) Water (120) Inorganics (90) Fermentation Distillation Process and Alcohol (117 MT/150 KL) Spent Wash (240) Organics (residual ferm. Sugars, non ferm. sugars and other organics (153) Inorganics (90) Anaerobic Digestion of spent wash having 153 MT of organic mass 70 % efficiency) Methane (30.94) CO2 and other gases (76.16) VSS separation from partially treated spent wash (45.9) VSS (18.9) Multi Effect Evap. (117) Organics 27 Inorganics - 90 Conc. Spent Wash (170) Steam Dryer for drying of conc. spent wash (170) Dried Spent Wash (130) Coal (45) Dewatered Yeast and ETP + digester Sludge (25) Pelletisation of dried spent wash, coal and Yeast and ETP Sludge (200) Pellets to Incineration Boiler (200) Fertilizer Ash for fields (100) Figure : Idealized Mass Balance for spent wash handling All values are in MT/day Khandoba Distilleries Ltd. Solapur (Maharastra)