Small Scale NZ Biofuel Techno-Economic Investigation
description
Transcript of Small Scale NZ Biofuel Techno-Economic Investigation
Small Scale NZ Biofuel Small Scale NZ Biofuel Techno-Economic Techno-Economic InvestigationInvestigation
VISHESH ACHARYAVISHESH ACHARYAMASTER OF ENGINEERINGMASTER OF ENGINEERING
DR. BRENT YOUNGDR. BRENT YOUNGCHEMICAL AND MATERIALS ENGINEERINGCHEMICAL AND MATERIALS ENGINEERING
UNIVERSITY OF AUCKLANDUNIVERSITY OF AUCKLAND
OVERVIEWOVERVIEW
Introduction to Bio EthanolIntroduction to Bio Ethanol Benefits of Blending Ethanol with PetrolBenefits of Blending Ethanol with Petrol Bio Ethanol Manufacturing ProcessBio Ethanol Manufacturing Process Classification of feedstockClassification of feedstock Potential of various Starch, Sugar and Potential of various Starch, Sugar and
Cellulosic materials as Feedstock in NZCellulosic materials as Feedstock in NZ ConclusionsConclusions
What is Bio Ethanol?What is Bio Ethanol?
Alcohol based liquid fuel made from Alcohol based liquid fuel made from agricultural bio massagricultural bio mass
Produced by fermenting sugar from Energy Produced by fermenting sugar from Energy crops crops
EU, USA and Brazil mandate a minimum EU, USA and Brazil mandate a minimum ethanol blend.ethanol blend.
NZ govt mandates selling a minimum of 0.25% NZ govt mandates selling a minimum of 0.25% of all fuel sold to be that of Bio fuels, starting of all fuel sold to be that of Bio fuels, starting 20082008
Benefits of Blending Benefits of Blending Ethanol with PetrolEthanol with Petrol
Contains 35 mole percent OContains 35 mole percent O22
Acts as an oxygenate – facilitates combustion to a Acts as an oxygenate – facilitates combustion to a greater extentgreater extent
Increases energy efficiency by 1%Increases energy efficiency by 1%
EmissionReduction in
Emissions
Carbon Monoxide 25-30%
Carbon Dioxide Up to 10%
Volatile Organic Compounds 7%
SO2 Decrease
Aromatics Decrease
Manufacturing ProcessManufacturing Process
PRE-TREATMENT
ENZYMES
FERMENTATION
ENZYMESYEAST
123
456
123
456
BEER STRIPPER
RECTIFIER
SOLIDS
50% EtOH
10% EtOH
WATER
95% EtOH
DEHYDRATOR
99.6% FUEL GRADE
ETHANOL
AZEOPTROPIC
Feedstock
HYDROLYSIS
Classification of FeedstockClassification of FeedstockClassified into 3 types depending upon the constituent sugars
• SACCHARINE: Directly fermentable 6 and 12 C sugars
Glucose, Fructose and Maltose
E.g. Sugar cane, Sugar beet, Whey, etc.
• STARCH: Carbohydrates such as Starch and Inulin
E.g. Maize, Wheat, Potatoes, etc.
• CELLULOSE: Common material in plants
Primary constituent of plant cell wall
Wood, wood waste, paper, straw, etc.
SACHHARINEFruits Molasses
STARCHGrains Potatoes
CELLULOSEDRY Green
MASHING
DILUTION DILUTION
LIQUEFACTION
MILLING
HYDROLYSIS HYDROLYSIS
PRE TREATMENT SHREDDING
FERMENTATION
DISTILLATION
DEHYDRATION
DENATURING STORAGE
MASHING
DILUTION
Starch CropsStarch Crops Maize, Wheat, Barley and Milo Maize, Wheat, Barley and Milo
(Sorghum) are the most extensively used (Sorghum) are the most extensively used Starch based feedstockStarch based feedstock
Maize is the most widely used feedstockMaize is the most widely used feedstock
Current annual production of Maize Current annual production of Maize based ethanol is ~20 Billion Lbased ethanol is ~20 Billion L
Ethanol from MaizeEthanol from Maize
Ethanol from Maize is produced by 2 methods:
1. Dry Milling
Ethanol - Primary product
Distiller Dried Grains and Solubles (DDGS) and CO2
– Secondary Products
Typical yields: 460 L EtOH/T Maize
380 kg DDGS/T Maize
Dry Milling Process for the production of Ethanol from Maize [Henderson, C. (2006)]
Ethanol from MaizeEthanol from Maize
2. Wet Milling2. Wet Milling
Gluten Feed, Starch, Corn oil, Corn Germ and Corn Syrup Gluten Feed, Starch, Corn oil, Corn Germ and Corn Syrup Liquid – Primary products.Liquid – Primary products.
Starch is further hydrolysed and fermented to EthanolStarch is further hydrolysed and fermented to Ethanol Typical Yield: 440 L EtOH / T Dry MaizeTypical Yield: 440 L EtOH / T Dry Maize Yield lower than Dry milling as some starch is lost in co-Yield lower than Dry milling as some starch is lost in co-
products.products. Process more complex than Dry millingProcess more complex than Dry milling Hence, requires higher capital investmentHence, requires higher capital investment
Wet Milling Process for the production of Ethanol from Maize [Henderson, C. (2006)]
Ethanol from NZ MaizeEthanol from NZ Maize
150,000 tonne Maize grown on 13,000 Ha. of land150,000 tonne Maize grown on 13,000 Ha. of land
NZ Maize yield: 12.5 t/Ha (U.S. Maize yield: 8 t/Ha)NZ Maize yield: 12.5 t/Ha (U.S. Maize yield: 8 t/Ha)
Energy input for un-irrigated arable Maize farming in Energy input for un-irrigated arable Maize farming in NZ : 1683 MJ / t MaizeNZ : 1683 MJ / t Maize
Avg. US Maize farming input : Avg. US Maize farming input : 24252425 MJ / t Maize MJ / t Maize
Cost – Ethanol from NZ Cost – Ethanol from NZ MaizeMaize
Potential Yield: 397 L EtOH / t MaizePotential Yield: 397 L EtOH / t Maize Dry Mill Process, 95 ML/yrDry Mill Process, 95 ML/yr
90.3 NZc/L EtOH90.3 NZc/L EtOH Maize sourced from within 100km @ NZ$10/tMaize sourced from within 100km @ NZ$10/t
Wet Mill Process, 95 ML/yrWet Mill Process, 95 ML/yr 76.6 NZc/L EtOH76.6 NZc/L EtOH Maize sourced from within 100km @ NZ$10/tMaize sourced from within 100km @ NZ$10/t
Ethanol made using Geothermal Steam to be Ethanol made using Geothermal Steam to be cheaper by 4.5 NZc/Lcheaper by 4.5 NZc/L
Ethanol from Sugar CropsEthanol from Sugar Crops Sugar Cane and Sugar Beet widely used Ethanol feedstocksSugar Cane and Sugar Beet widely used Ethanol feedstocks
Brazil produced 4.5b Gallons of Ethanol in 2006Brazil produced 4.5b Gallons of Ethanol in 2006
Contains Sucrose which can be directly fermented into EthanolContains Sucrose which can be directly fermented into Ethanol
Hence, processes are relatively simpler and more cost effectiveHence, processes are relatively simpler and more cost effective
Sugar Cane is of particular interestSugar Cane is of particular interest Has high ethanol yield: 7750 L/Ha (Corn: 2750 L/Ha)Has high ethanol yield: 7750 L/Ha (Corn: 2750 L/Ha) Shorter fermentation period of 6-10 hours (Corn: 48 - 72 hrs)Shorter fermentation period of 6-10 hours (Corn: 48 - 72 hrs)
Ethanol from Waste Ethanol from Waste Products – Cellulosic WasteProducts – Cellulosic Waste
Cellulosic materials – most abundant and potentially Cellulosic materials – most abundant and potentially cheap feedstock for ethanol productioncheap feedstock for ethanol production
Includes wastes from agriculture, forest and municipal Includes wastes from agriculture, forest and municipal solid waste.solid waste.
Potential to exploit 290,000 t.p.a of landfilled paper Potential to exploit 290,000 t.p.a of landfilled paper waste and 430,000 t.p.a. of cereal straw.waste and 430,000 t.p.a. of cereal straw.
Manufacturing cost estimated at NZ$0.7-NZ$1.30/ L Manufacturing cost estimated at NZ$0.7-NZ$1.30/ L EtOH EtOH
Technology currently exists on Lab. scale onlyTechnology currently exists on Lab. scale only
Ethanol from Potato Processing WasteEthanol from Potato Processing Waste
500,000 t.p.a grown on 20% of total arable farm land500,000 t.p.a grown on 20% of total arable farm land Solid potato waste accounts for about 20% of potato Solid potato waste accounts for about 20% of potato
cropcrop Potatoes have a high fermentable carbohydrate Potatoes have a high fermentable carbohydrate
content of 20% w/wcontent of 20% w/w Starch from 150,000 tonne potato waste can be Starch from 150,000 tonne potato waste can be
potentially converted to 1.5 MML of ethanolpotentially converted to 1.5 MML of ethanol Estimated production cost: NZ$1.4-1.5 / L EtOHEstimated production cost: NZ$1.4-1.5 / L EtOH Co-processing with other feedstock likely to reduce Co-processing with other feedstock likely to reduce
these costs by 50c to NZ$0.9-1.0 / L EtOHthese costs by 50c to NZ$0.9-1.0 / L EtOH
Ethanol from Fruit Crop Ethanol from Fruit Crop Waste – Kiwi fruitWaste – Kiwi fruit
Kiwi fruit has very high content of Starch, Kiwi fruit has very high content of Starch, Fructose and Sucrose.Fructose and Sucrose.
Fermentable sugar content estimated as 8%Fermentable sugar content estimated as 8%(w/w).(w/w).
Average ethanol yield of 44 L EtOH/t kiwi fruit.Average ethanol yield of 44 L EtOH/t kiwi fruit. Cost of making ethanol from kiwi fruit, in an Cost of making ethanol from kiwi fruit, in an
already existing ethanol plant is estimated at already existing ethanol plant is estimated at NZ$0.7-0.8/ L EtOHNZ$0.7-0.8/ L EtOH
ConclusionsConclusions
NZ grows several agricultural products that NZ grows several agricultural products that have the potential to be converted into bio have the potential to be converted into bio ethanolethanol
Sugars crops such as Sugar cane are easier to Sugars crops such as Sugar cane are easier to process than Starch crops such as Maize.process than Starch crops such as Maize.
Ethanol can be produced in NZ at the cost of Ethanol can be produced in NZ at the cost of NZ$0.7-1.0/L EtOH depending upon the NZ$0.7-1.0/L EtOH depending upon the feedstock used.feedstock used.
AcknowledgementAcknowledgement
Foundation of Research Science and Foundation of Research Science and Technology (FRST) for their generous Technology (FRST) for their generous financial supportfinancial support
Derek Turnbull, Steve HolmesDerek Turnbull, Steve Holmes
Tamaki Controls Ltd.Tamaki Controls Ltd.
Project MentorsProject Mentors