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Introduction

Brief Background The mango industry, which is one of the Philippines aid in sustaining the country’s economy, produces about 685 thousand metric tons of mango from January 2018 up to September 2018 (Philippine Statistics Authority, 2018). Around 41% of the total mango production is then used for the mango processing industry (BAS, 2004) which accumulated to roughly around 281 thousand metric tons of processed mango products such as dried mango, mango puree and mango concentrates. Majority of the processing plants for the production of dehydrated candied and puree mangoes are located in Cebu. Profood, which is one of the main exporter of processed mango, have an operating capacity of 1140 metric tons of mango per day (Galolo, 2017) along with nine more mango processing plants based in Cebu making Cebu as a top producer and exporter of processed mango products. Along with banana, pineapple and other agricultural products, processed mango products has played an important role in the foreign trade market. Philippines, being ranked seventh amongst the exporters of fresh and dried mangoes, exports around 4% share of the global market and 98% of the total production is used for domestic consumption (Couto et.al, 2017). Processing of mango come into life for the purpose of extending the mangoes shelf life since ripe mangoes tend to degrade faster causing for a loss in profit and also, accumulation of wastes in the landfill. In the said processing of mangoes, only the flesh part of the mango is used and is then processed to produced dried mango, puree, candies,

2 and juice concentrates as its end products leaving 50% by-products or wastes such as mango seeds and peels. Around 40%, by average, is the percent waste accumulated by the mango seeds (Feedipedia, 2016). According to Istiana et.al (2017), using Luff Schoorl testing method, Mangifera Indica L. species of mango seeds has a glucose content of 15.29% which can be therefore be used to produce a bioethanol through converting the glucose content into alcohol using the fermentation process and distillation process for purification. Mango seeds are normally dried and is used as fuel for the reboiler. However, due to large amounts of mango being processed every day, generation of mango seeds and its storage is becoming a problem for the processing plants. As a raw material being this abundant, as well as the need of its proper disposal and high market gap of bioethanol in the country, mango seed wastes can be of used as a raw material in producing bioethanol. Bioethanol, on the other hand, is a fuel that contains energy from geologically recent carbon fixation, produced from living organisms, such as plants and algae. Fuels are made by biomass conversion. The biomass can be converted into liquid fuel. Biofuels have increased in popularity because of rising oil prices and the need for energy security (Jacques et.al, 2015). Bioethanol is also used as an additive for gasoline because of its property that oxygenates the fuel mixture so that it burns completely and can therefore reduce greenhouse gases emission. Greenhouse gases are the one to blame for the rapid increase of temperature of the Earth’s atmosphere so to cut down greenhouse gases emissions, experts, scientists, researchers and the government aimed to switch to alternative source of energy aside from the use of fossil fuels. At present time, the most common blend is 90% gasoline and 10% ethanol which the blend is called E10 (Pirolini,

3 2015) but the Department of Energy wants to pursue the E20 or 20% ethanol blend in gasoline by the year 2020 (USDA, 2017). The only thing that hinders the E20 blend is the lack of renewable sources of raw material and lack of bioethanol plant operating in the country. Therefore, this driven the researchers to come up with a plant design for the production of bioethanol using mango seeds. The name of the plant will be MaKernel Bioethanol Plant. The logo of the company is

Objectives of the Study The main objective of this study is to come up with a plant design for the production of bioethanol from mango seeds kernel. Furthermore, the specific objectives of this study are: 1. To generate a process that will be able to produce bioethanol from mango seeds kernel using two stage acid hydrolysis 2. Conduct a market study which includes the evaluation of the local market production of bioethanol

4 3. Select a plant location that provides proximity to the source of raw material, provides good target market and is easily accessible. 4. To provide the necessary design of all the equipment needed for the production of bioethanol and the treatment of the waste produced based on the material balances attained. 5. Prepare financial statements for the first five years of operation of the plant

Scope and Limitations The study of the production of bioethanol using mango seeds kernel as the raw material is objectively chosen based on market, technical, financial and social aspects of business. Mango seeds waste will be the main raw material that will be used in this plant design which will be supplied by the mango processing industries in Cebu. The proposed plant will be located near to the source of raw material and water. All designs made are purely theoretical and are based for the ideal operation of the plant. The proposed duration of the construction of the plant will be roughly around two years and a financial study covering the first five years of the plant operation will be provided. Estimates for the costs of goods, equipment, buildings, facilities, labor and services were taken from Chemical Engineering books and other reliable internet sites. Significance of the Study The study of the Production of Bioethanol from Mango Seeds Kernel will be of great benefit to the following:

5 Biofuel Industry. Production of bioethanol from a new source of raw material which is mango seeds kernel will be of great benefit to the biofuel industry in the Philippines especially now that the target ethanol blend for gasoline is E20. As the demand of the bioethanol increases, the demand for renewable sources also increases. Environment. Due to the increasing consumption of fossil fuel every year, generation and accumulation of toxic pollutants and compound in the atmosphere increases which are harmful to the environment. Therefore, the use of bioethanol mixed in the gasoline is helpful to the environment because it reduces greenhouse gases, it is carbon neutral and it can be easily diluted to non-toxic concentrations or can be easily degraded in case of fuel spills. By-product gases produced by bioethanol is much cleaner compared to petroleum based fuels. Community. From the construction up to the operation of the plant, many will be given jobs which results to the increase in employment rate of the people in the community that would somehow help them in providing their needs. Increase in the economic growth of the city is also one of the great opportunities that the community can benefit for the building of a bioethanol plant in their place. Mango Processing Industries. Mango seed is an industrial waste generated from the mango processing industries. It is considered as a waste material of dried mango manufacturers that causes problem of storage and contributes to the pollution in the processing plants due to its

6 accumulation on the surroundings. Utilization of the mango seeds by using it as a raw material for the production of bioethanol can help reduce the problem of the dried mango manufacturers in their storage problem and cost for disposal.

7 Chapter 1 Market Study

Product Description Ethanol, C2H5OH is an alcohol, a group of chemical compounds whose molecules contain a hydroxyl group, –OH, bonded to a carbon atom. Ethanol is a natural byproduct of plant fermentation. Since ethanol is produced from plants that harness the power of the sun, ethanol is also considered as a renewable, environment-friendly fuel that is inherently cleaner than gasoline. On the other hand, Bioethanol is a good source of renewable fuel. Its expanding use is helping to reduce harmful pollutants in our air. Bioethanol is produced through processing biological matter, either waste products or crops grown specifically for the purpose of creating Ethanol. In Philippines, gasoline and petroleum diesel is blended with 10% v/v bioethanol and used in motor vehicles to improve vehicle emissions and power. The raw material used to produce bioethanol product is Mango seed kernel which considered waste by the Mango processing industries. The mango seeds were known to contain sugar make it a potential feedstock for bioethanol production and this will be done by fermentation of glucose with Saccharomyces cerevisiae producing high grade bioethanol. Product Demand Within the span of seven years, local bioethanol supply increased approximately 12 times, ranging from 23 million liters (ML) in 2009 to 274 ML in 2017, resulting to the reduction of bioethanol importation to about half of the total bioethanol requirement.

8 With the expected entry of three more bioethanol distilleries by 2018 with a combined capacity of 149M L, local bioethanol supply can cover about 72% of the current bioethanol requirement at E10, based on the assumed local bioethanol distilleries utilization rate of 100%. However, increase in the bioethanol blending to E20 by 2020 corresponds to a rise in bioethanol supply requirement from 605M L in 2018 at E10 to a projected 860M L in 2020 using E20. Assuming a 100% local bioethanol distillery utilization rate, the realistic local bioethanol capacity in 2020 is only about 386M L, or 45% of the bioethanol supply requirement in 2020 implementing E20. The following table shows the ethanol blend targets and implementation dates since inception. As an aspirational goal, the DOE wants to make available an 85 percent ethanol blend to be promoted voluntarily by 2025. (* aspirational and voluntary goal)

Table 1 Percent Ethanol Blend of Gasoline for the Past years Year

% Blend

2009

5

2011

10

2015

10

2020

20

2025

20/85*

Product Supply Table 2 shows the ten accredited bioethanol producers here in the Philippines while Table 3 shows the additional bioethanol plant constructed for the sole purpose of

9 decreasing the importation of bioethanol and utilizing the feedstock available in the country.

Table 2. List of Accredited Bioethanol Producers Producer Registered

Location

Feedstock

Capacity (Million liters/ year) San Carlos

40

Bioenergy Corp.

San Carlos City,

Sugarcane

Negros Occidental

Leyte Agri Corp.

9

Ormoc City, Leyte

Molasses

Roxol Bioenergy

30

La Carlota City,

Molasses

Corp. Green Future

Negros Occidental 54

Innovations, Inc Balayan Distillery,

San Mariano,

Sugarcane

Isabela 30

Calaca, Batangas

Molasses

15

Apalit, Pampanga

Molasses

14.12

Talisay City,

Molasses

Incorporated Far East Alcohol Corp. Kooll Company Inc. Universal Robina Corporation

Negros Occidental 30

Bais City, Negros Oriental

Molasses

10 Absolute Distillers

30

Lian, Batangas

Molasses

30

Nasugbu, Batangas

Molasses

Inc. Progreen Agricorp Inc. Total

282.12

Table 3. Certificate Registration with Notice to Proceed Producer Registered

Location

Feedstock

Capacity (Million liters/ year) Cavite Biofuels

38

Magallanes, Cavite

Sugarcane

45

Bago City, Negros

Sugarcane

Producers, Inc. Canlaon Alcogreen Agro Industrial

Occidental

Corp. Emperador

66

Distillers, Inc. Total

Gimalas, Balayan,

Sugarcane/

Batangas

Molasses

149

Source: Department of Energy

Based from Table 2 and Table 3, as given by the Department of Energy, there are currently 13 bioethanol plants registered in the crop year 2017-2018. Meanwhile, according to the Sugar Regulatory Administration, the country’s ethanol production

11 gradually increases every year but is still short of the annual demand of 174.12 million liters. Insufficient feedstock availability and high domestic ethanol price are the two main challenges identified to bridge the bioethanol supply gap and accelerate local bioethanol investment. At present time, Philippines uses only molasses and sugarcane for bioethanol production. However, available molasses in the country cannot cater the demand for an E20 blend. Additionally, sugarcane is used in the production for bioethanol and as well as for the production of sugar which is a common necessity in the country. Higher price of local ethanol than gasoline is also a factor that threatens the stability of the Philippines bioethanol production (Demafelis et.al, 2017). Demand – Supply Analysis The Philippines was the first country in Southeast Asia to enact biofuels legislation. The blend mandate was gradually increased in accordance with the Biofuels Act of 2007, ending with a 10 percent ethanol requirement in August 2011, which remains the current mandate. However, meeting this target with domestically produced ethanol has been a challenge due to the inadequate capacity of existing sugarcane distilleries, low productivity and high production costs (Foreign Agricultural Service, 2016). Imported ethanol is expected to satisfy at least one quarter of the domestic demand in the Philippines for the next several years even though domestic production capacity is catching up. Fuel use is predicted to increase as the population and economy continue to expand (Foreign Agricultural Service, 2016). Increasing motor vehicle sales, accelerating construction activities, a growing population and continued expansion of the Philippine economy, all translate to increased

12 fuel consumption in the next 3 - 5 years. According to GAIN report, as of year 2018 the fuel consumption is 605 ML which is composed of the fuel production and fuel imports of 280 ML and 325 ML, respectively. The present distilleries can supply 431.12 ML of bioethanol leaving a 173.88 ML market gap. The plant will produce 17.4 ML of bioethanol per year contributing to about 10% of the market gap. It will therefore cut down the market gap to about 156.49 ML in the year 2019. Moreover, the capacity is based on the growing demand and consumption and inadequate domestic production of bioethanol. Price Study According to Sugar regulatory administration the average bioethanol price index for 2nd half of the crop year 2017 – 2018 is at Php 50 per Liter however on July 2018 the reference price increase to Php 58.08 compared to Php 42.42 per liter. Prices are seen moving when the 4th quarter comes because of the start of milling season where molasses is available (Biofuels Digest, 2018). Mango seeds has an average market value of Php 725 per ton and it is available all year round. Compared to the molasses that is Php 8,216 per ton. Using the mango seed as a feedstock for bioethanol productions will help the energy sector in finding a new source of ethanol that can cater the consumers demand. Marketing Program The marketing program for bioethanol from mango seed wastes will be as focused on the following: 1. Raw material will be used promotes environment friendly program;

13 2. Emphasize key advantages of the product that can be compared to sugarcane-, raw sugar-, molasses-derived and imported ethanol; 3. Create a strong distribution channels to ensure stability of production; 4. Offer a competitive price at the level of Philippine market; 5. Focus for local Filipino distributors as key target for the market; and 6. Build a relationship business, long-term relationships, not single-transaction deals with customers.

14 Chapter 2 Technical Study

Raw Material Mangoes proved to be abundant in the Philippines with roughly around 800 to 900 thousand metric tons of mango produced annually in the country. This is due to the country’s location which fits the conditions needed to grow a mango bearing tree. According to Philippine Statistics Authority in the year 2018, the country still has an existing production area of 185,194 hectares with 9,460,132 number of bearing trees. Base on export volume and value, mango industry is one of the aid for Philippines industry economic standing. Peak season for harvesting mangoes is between April to June, however, Central Visayas and Mindanao produce mango fruits during off season to avoid the oversupplying of mango during the peak season. According to K&R United (2016), production of mango fruit in the country is all year round compared to other countries such as Indonesia, USA, Malaysia and Thailand which harvest time for mango are only around 2 months, 4 months, 4 months and 8 months, respectively, per year. Around 90% of the total production of mango in the country is used for local consumption while the remaining 10% are the only ones exported. Processed mango products such as dried mangoes, purees, or concentrated juices takes the 41% of the mango supply left for local consumption (AgriBusiness, 2016). There are several mango processing companies currently operating in the Philippines which causes a rapid accumulation of mango wastes that is not utilized well and ended up being a pollution.

15 From this mango consumption, the part of the fruit which always becomes waste and is discarded are its seed. Since mango seed is a large industrial waste available due to expanding mango processing plants, and lack of bioethanol supply in the country, a research about the possibility of converting the mango seeds kernel as a renewable source of energy such as bioethanol were conducted (Cristina,2017). By average, around 40% of the total weight is the weight of the mango seed in the entire fruit and around 60% of the total weight of the mango seed is composed of the kernel (Archimede et.al, 2015). According to Cristina et.al.(2017), mango seeds kernel cont201ains 15.29% of soluble sugars. Additionally, Table 1 shows the chemical composition of mango seed kernel (MSK) using the values taken from the research study of Chime et.al, (2017). These includes the cellulose, hemicellulose, and lignin content which can be further convert into sugar using acid hydrolysis.

Table 4. Chemical Composition of MSK Constituents

Dry weight, %

Ash

3.88

Fat and Wax

8.7

Lignin

15.0

Hemicelluloses

34.06

Cellulose

25.2

Using all the data gathered, this proves that utilizing the mango seed waste is the best suitable raw material to be used in the process to produce bioethanol.

16 Manufacturing Process Schematic Diagram. Figure 1 shows the overall processes involved in producing bioethanol from mango seeds. Mango Seeds Breaking Rolls Sieving Water

Mango seed kernel powder 70% H2SO4

1st Stage Acid Hydrolysis

Outer Shell

Drying

Milling Biomass

2nd Stage Acid Hydrolysis

Acid-sugar-solution

Recovered H2SO4

Gypsum

Yeast, DAP, Urea

Electrodialysis Neutralization

Ca(OH)2

Fermentation

Carbon Dioxide

Distillation Dehydration

Slops

Ethanol

Figure 1. Schematic diagram for producing bioethanol from mango seeds

30% H2SO4

17 Process Involved. Preparation of Mango Seed Kernel (MSK). Mango seeds will be collected from wastes produced from various mango processing plants which are located in Cebu and other places in the Philippines. Breaking Rolls. Mango seed contains, by average, around 60% kernel and the remaining 40% for the outer shell. The material needed for the process is the kernel so the mango seeds undergo the crusher to free the kernel inside of the mango seeds. Sieving. Since the outer shell and the MSK are mixed, a sieving machine which is used to separate the two. The outer shell is then used for the boiler while the MSK proceeds to the next process. Drying. The MSK which contains 44.4% moisture will be dried to achieve a 12% moisture. Co-current rotary drier will be used to the process for the purpose of reducing the moisture content of the MSK. Milling. After the MSK have been dried, it further undergoes milling to reduce its particle size up to 40 mesh through the use of pin mill. Acid Hydrolysis. The powdered MSK will undergo a two-stage acid hydrolysis process to convert the lignocellulosic materials into fermentable sugars. Arkenol process will be used in converting the lignocellulosic materials into sugars.

18 1st Stage Acid Hydrolysis. The powdered MSK which consists of 25.2% cellulose, 34.06% hemicelluloses,15% lignin, 15.29% soluble sugar and the remaining is made up of solids, will be subjected to a dilute sulfuric acid pre-treatment for 20 minutes for the purpose of achieving high reaction rates and improving the hydrolysis of cellulose. Sulfuric acid (70% v/v) with a ratio of 1 g biomass per 1.25 g of acid will be used for the breaking down of complex structures such as cellulose, hemicellulose and lignin which is then converted into fermentable sugars. The working temperature will be 50oC. A mass of 17,231 kg per hour of sulphuric acid will be used. According to Arkenol Technology, the acid hydrolysis process converts 90% of cellulose, hemicellulose and lignin into fermentable sugars. 2nd Stage Acid Hydrolysis. For the 2nd stage of acid hydrolysis, biomass produced from the previous hydrolysis process will react with 30% sulphuric acid with a ratio similar to that in the 1st stage acid hydrolysis. With a working temperature of 100oC, the mixture will be thoroughly mixed with a retention time of 30 minutes per batch. A biomass having a flow rate of 4,702 kg per hour will be used. The acid-sugar solution will be further processed while the biomass left will be collected to be used as fertilizers. Electrodialysis. A total of 33,100.26 kg per hour of acid-sugar solution contained from two stages of acid hydrolysis enters the electrodialysis tank, where an assumption is made that 95% of the H2SO4 will be recovered and will be returned back to the two-stage acid hydrolysis while the remaining sugar solution with 5% remaining H2SO4 will be

19 forwarded to neutralization process. A retention time of 15 minutes and working of temperature of 60oC will be used. Neutralization. The acid-sugar solution which contains fermentable sugar will be neutralized with Ca(OH)2 to the pH conditions (4.4-4.6) which is the best suitable pH solution for fermentation. Sulfuric acid neutralized using Ca(OH)2 produces a byproduct which is gypsum. Gypsum is then allowed to settle down in the neutralization tank which is then further filtered. Gypsum can be sold which can be an additional profit for the company. Ethanol Fermentation. The obtained sugar solution with a brix of 19, which is ideal for fermentation, undergoes fermentation for the conversion of fermentable sugars into bioethanol by using yeast, or the Saccharomyces cerevisiae. The sugar solution will be further supplemented with other nutritional components of fermentation such as urea and DAP which are needed by the yeasts to achieve higher activity rate from the yeasts. The pH will then be maintained within the range of 4.0-4.2. This process will start by feeding a small amount of fermentable sugar solution in the culture vessel containing yeasts for propagation (Piriya et.al,2012). There will be three culture vessels for the growth of yeasts cells, which will then be transferred in the three pre-fermenter tank for its propagation and growth. Fermentation will occur by fed-batch method. The fermentable sugar solution will be fed gradually to the main fermenter.

20 Filter. The beer produced from the fermentation process will undergo filtering to remove the residue which are the yeast, DAP, urea and solids that were not filtered. Clarified beer will then be further processed in the distillation. Distillation. The clarified beer which contains 6.64% (v/v) enters the distillation and is then heated up to 78.5oC which is its operating temperature which is determined using the differences of volatilities of components in a mixture. Using the principle of distillation, low boiling components are concentrated in the vapour phase, and the vapour is then condensed giving a more concentrated less volatile compounds in a liquid phase. In ethanol production, and efficient distillation tower is used to separate the water and ethanol. Water, having the high boiling point stays in the bottom while the ethanol is obtained from the top of the tower (Onuki, 2008). A good distillation obtains 95% (v/v) ethanol in the distillate and 2% (v/v) ethanol in the bottoms. Dehydration. An extra process is required before the final blending of the pure ethanol with gasoline because the required purity of ethanol to be used for blend with the fuel is 99.99%. Since distillation only achieved 95% purity, the distillate will undergo further separation of water and ethanol with the use of molecular sieve dehydrator. In ensuring the level of dryness in final ethanol product but not compromising the energy consumption of the plant, zeolite has been proven to be ideal. The dehydration process will be using Zeolite 3A as the adsorbent of the Pressure Swing Adsorption process.

21 Mass Production Flow Rate. Different manufacturing plants, mainly dried mango and mango juices manufacturing plant, are considered as source of the raw material with the basis of 50 tons per day per manufacturing plant, of waste generated during off season and is expected to increase during peak season (Profood Corp., 2016). As of present time, a total of 46 manufacturing plants for the production of dried mango and mango juices exists in the country. The desired production per year is the 10% of the present market gap of the bioethanol industry here in the Philippines for the year 2018 which is 17.4 Million Liter. A total of 58,000 L per day of bioethanol is used as the basis. The mass of mango seeds to be processed is based on the capacity of Profood, which is one of the main exporter of processed mango, with an operating capacity of 1140 metric tons of mango per day (Galolo, 2017) along with nine more mango processing plants which is also based on Cebu. However, the presumptive amount of mango seeds calculated needed per day to provide the required 58,000 L of ethanol have a small discrepancy due to other processes added and the loss per process undergone by the raw material compared to the study of Cristina et al. which causes some variations in the yield of the bioethanol. Figure 2 shows the mass flow rate diagram of the entire operation. It is the material balance in every process which indicates the mass of the material that goes in and goes out in a process.

22

Figure 2. Mass Flow Rate Diagram

23 Process Flow Diagram. The process flow diagram is used to illustrate the entire process of operation involved in a bioethanol plant. Figure 3 shows the block flow diagram of the each processes the raw material undergoes before it produce the main product, the bioethanol. Figure 4 shows the production flow diagram which shows the equipment and vessels used in every process in the entire operation.

24 Acid

MSK

Breaking Rolls

Sieving

Drying

Outer Shell

Water

Milling

Acid

Centrifugal Separation

Yeast, DAP, Urea

Ca(OH)2

Fermentation

Neutralizatio n

Undissolve d yeast and suspended solids

Electrodialys is

95% Alcohol Biodigester

Slops Figure 3. Block Flow Diagram

2nd Stage Acid Hydrolysis

Recovered H2SO4

Gypsum

CO2

Beer

1st Stage Acid Hydrolysis

Distillation

Dehydration

At least 99.99% alcohol

25

Figure 4. Production Flow Diagram

26 Power Plant Diagram. Electrical power generation has long been recognized as highly inefficient. Two-thirds of the energy fueling the process is wasted as unused heat after high pressure, high temperature steam does its work. When the typical efficiency of electrical generation is added to the typical efficiency of a boiler system providing process heat to an ethanol plant, the combined efficiency is roughly 49 percent. Bringing the power generation to the ethanol plant and making use of the electrical generation's waste heat in a combined heat and power (CHP) system, boosts that efficiency to 75 percent. Increasing the efficiency of power and steam generation, in turn, reduces carbon emissions (Schill, 2009). Instead of separately purchasing electricity from the local grid and a gas boiler for onsite heating, the plant will use power co-generation technology for its operations (Cogen, 2017). A combination of biomass such as Napier grass, mango seed shell and methane, which are recovered from the process, will be used in the co-generation plant as boiler fuel. Through conveying system that connects biomass shed and biomass-fired boiler, the biomass will be fed to the furnace. Demineralized water from water treatment plant will be used in the boiler to avoid scaling in the boiler and pipes. This water will be converted to steam through heating in the furnace. The steam from the boiler will pass through super heaters, to be heated above its saturation temperature, which will convert it from saturated steam or wet steam to superheated steam or dry steam (Vallourec, 2017). And then transformation of thermal energy to mechanical energy takes place where the high-pressured steam will pass through a series of rotor blades of the non-condensing turbine (Thermal Engineering, 2011). The turbine will be connected to a generator where

27 mechanical energy will be converted to electrical energy that will supply power to the entire bioethanol plant. The steam from the turbine will then be used for the production of bioethanol in the process area. The exhaust stream from the production will be liquefy in a condenser and will be cooled down through the cooling tower. The cooled water will undergo recovery in the water treatment plant and will supply the demineralized water that will recirculate in the power plant. Before heating in the economizer and feeding it to the boiler, the demineralized water will be introduced in the deaerator. The deaerator has significant importance in remove the trapped air in the water molecules which can affect the boiler drum badly and lead to corrosion (Sethi, 2016). The flue gas coming from the boiler can be further utilized through the use of economizer, part of the heat will be extracted to heat the feed water to the boiler. The rest of the flue gas will be introduced in the gas scrubber before releasing it to the atmosphere. The use of economizer reduces the fuel consumption thus, increasing the boiler efficiency (Sethi, 2016). Figure 5 shows the Power Plant Diagram of the bioethanol plant.

28

Figure 5. Power Plant Diagram

29 Waste Water Treatment Plant. The process will be carried out in anaerobic digester. The slops will then be fed into the reactor where anaerobic bacterial culture will be maintained in suspension. Inlet temperature of the slops will be assumed to be at 40oC. According to Metcalf and Eddy (1991), an average period of 10 days as a residence time for anaerobic digestion at 40oC is the recommended time for the slops to be retained in the reactor. Produced gas such as methane gas and carbon dioxide gas due to the decomposition of organic matter present in the wastewater are then fed into the degasser for the separation of two gases. Methane gas will then be fired to the boiler meanwhile the carbon dioxide will be produced will be stored to sell it out for usage in carbonated drinks. The remaining wastewater after the anaerobic digestion process will flow to the clarifier for further treatment before it will be completely disposed to the lagoon. Important parameters such as BOD, COD and pH of the wastewater will be monitored and reduced in order to meet the effluent standards set by the DENR. Figure 6 shows the waste water treatment plant diagram of bioethanol producing plant.

30

Figure 6. Waste Water Treatment Plant Diagram of a Bioethanol Producing Plant.

31 Ground Water Treatment Plant. Utilizing the ground water sources the location site provides, the bioethanol plant will provide its own water supply through deep well injection. The groundwater will be extracted from the source using pumps and the raw water tank will store the water pumped from the deep well. For the primary treatment, a sedimentation process will be done that will cause the suspended solids to form slurry which will then be moved to the center of the tank which is then collected in a trough (Fein and Kaplan, 2014). Therefore, the raw water from the tank will be fed to the clarifier to remove any suspended solids. The clarified water tank will store the collected overflow from the clarifier. The clarified water will then pass through the Activated Carbon Filter tank where through using activated carbon, organic matter from the feed water will be removed through adsorption process (Kneen, 1995). For the softening of water, or the removal of iron and manganese, the water will pass through the ion exchange unit. This involves a chemical process where water is filtered through an exchange media such as NaCl. As the water flows through the unit, the resin releases its sodium ions and trades them for calcium and magnesium ions (Penn State College of Agricultural Sciences, 2017). Lastly, the softened water then undergoes reverse osmosis. In reverse osmosis, the softened water will travel through semi-permeable membrane using pressurized pumps to filter out minerals and other contaminants. The water that will be collected after the process will be the demineralized water. The demineralized water will

32 go into the cooling tower to be fed to condenser and boiler. The rest of the demineralized water will be fed into the remaining process. The processed water tank will store the water from the activated carbon filter which will be used for the heat exchanger, fermentation and utilities. The softened water tank will store the water from the softening unit which will then be used for the hydrolysis process and utilities. For the water supply needed in the power plant, the demineralized water from the reverse osmosis process will be used which is then further stored in a demineralized water tank. Using the cooling water, the used water from the distillation process and power plant will be cooled down and recover it again in the water treatment plant for further use.

33 Production Schedule The plant will be designed to operate 24 hours a day, 7 days a week. A total of 300 days a year will the plant be operating while allocating the remaining 65 days for scheduled maintenance. Full inspection, repairs and modification of machineries and facilities are done during maintenance. For the production and engineering department, the daily 24 hour work schedule will be divided into 3 shifts (8 AM-4 PM, 4PM-12 AM, 12 AM-8 AM) where in each shift, there will be at least 2 on duty operators on each division and 1 supervisor. The initiation of shifts will start after steady-state condition of the plant is reached which is expected 2 months after the start-up of the plant. For the administrative department, they will have 8 hours (8 AM-5 PM) of duty per day with 1 hour of lunch period from 12 NOON to 1 PM, 6 days a week. The employees will continue on working on regular days, non-working holidays and will be entitled to leaves. Incentives will be provided for those who will work on holidays, both for all the departments. The plant has the capacity to process 38,685 kg of mango seeds per hour to produce 1,882 kg of bioethanol per hour. The maximum annual bioethanol production of the plant is 17.4 million liter which can help in boosting the country’s bioethanol supply and can cater the country’s increasing demand for bioethanol. Table 2.3.1 and 2.3.4 shows the number of employees under each department.

34 Table 5. Personnel with Shifting Schedule DEPARTMENT

POSITION

Administrative

Security Guards Nurse Driver Maintenance Supervisor Maintenance Staff Electrical Supervisor Instrumentation Supervisor Instrumentation Operators Power Plant Supervisor Power Plant operator Production Supervisor Raw Materials Handling Dryer and Mill Acid Hydrolysis Fermentation Distilling Column Operator Waste Treatment Plant Ground Water Plant Quality Control Analyst Laboratory Sampler Production Helper

Maintenance and Engineering

Production

NUMBER OF PERSONNEL SHIFT 2 SHIFT 3 SHIFT 1 (4 PM-12 (12 AM-8 (8 AM-4 PM) AM) AM) 4 4 4 1 1 1 1 1 1 1 1 1 2

2

2

1

1

1

1

1

1

1

1

1

1

1

1

2

2

2

1

1

1

2

2

2

1 2 2 1

1 2 2 1

1 2 2 1

1

1

1

1

1

1

2

2

2

2

2

2

5

5

5

35 Table 6. Personnel with Regular Day Schedule (8 AM- 5 PM) DEPARTMENT

Administrative

Production

POSITION Plant Manager Administration Head Human Resources Head Human Resources Staff Attending Physician Accounting and Finance Head Accounting and Finance Staff Sales and Marketing Head Sales and Marketing Staff Logistics and Purchasing Head Logistics and Purchasing Staff Production Head Engineering Head Maintenance Head Quality Control Officer Pollution Control Officer Safety Officer Driver

NUMBER OF PERSONNEL 1 1 1 1 1 1 2 1 1 3 1 1 1 1 1 1 1 4

36 Equipment Design and Specifications Rolling Mill (Ready Made). Function: To break the outer shell Model: FW 812 by CPM SKET Material to be crushed: Mango seed Number of unit: 3 units Capacity (each unit): 13,000 kg/hr Dimensions: Length: 2670 mm Width: 3740 mm Height: 1990 mm

Sieving (Ready Made). Function: to separate Mango kernel from seed Type: Vibrating screen Model: LDS1-2700-7.2 by Sinfonia Technology Co., Ltd. Number of unit: 3 units Capacity (each unit): 13,000 kg/hr Dimensions: Length: 4.5 m Width: 3.4 m Height: 2.4 m

37 Dryer (by Feeco International Inc.). Function: To reduce the seed moisture content from 44.4% to 12% moisture to maintains its viability and vigor in process. Type: Rotary Drum Dryer Number of Units: 3 units Capacity (each unit): 7736.93 kg/hr Heating System: Steam-heated air Gas Flow Pattern in Dryer: Co-current gas flow Residence Time: 1.69 hrs Dimensions: Length: 25.5 m Diameter: 2.88 m

Milling (Ready Made). Function: To reduce the size of kernel to optimum particle size Particle size: 0.212-1.180 mm Type: Pin mill Model: Simpactor Pin Mill by Sturtevant Inc. Capacity: 5000 kg/hr Dimensions: Length: 2.4384 m Width: 1.524 m Height: 2.5908 m

38 Hydrolysis. 1st Stage Acid Hydrolysis. Equipment: Pitched – blade turbine mixing reactor Function: Facilitates the breaking down of cellulosic and hemi-cellulosic lignin wall for the recovery of fermentable sugars Type of Material: Carbon Steel No. of Units: 1 Operation: Batch Operating time per batch: 30 min Feed Rate: 744,395.4 kg/day = 31,016.475 kg/hr Volume per unit: 15.657 m3 Dimension: Diameter: 2.585 m Height: 3.8775 m Working Pressure: 137.895 kPa Wall thickness: 5.765x10-3 m Width of Baffle: 0.2154 m No. of Impellers: 2 Impeller Diameter: 0.862 m Length of Blade: 0.2155 m Width of Blade: 0.1724 m Impeller above vessel floor: 0.862 m Lower impeller clearance: 0.862 m

39 Upper impeller clearance: 2.585 m

2nd Stage Acid Hydrolysis Equipment: Pitched – blade turbine mixing reactor Function: Facilitates the breaking down of cellulosic and hemi-cellulosic lignin wall for the recovery of fermentable sugars Type of Material: Carbon Steel No. of Units: 1 Operation: Batch Operating time per batch: 30 min Feed Rate: 253,901.97 kg/day = 10,579.25 kg/hr Volume per unit: 5.2896 m3 Dimension: Diameter: 1.8 m Height: 2.7 m Working Pressure: 137.895 kPa Wall thickness: 4.4547x10-3 m Width of Baffle: 0.15 m No. of Impellers: 2 Impeller Diameter: 0.6 m Length of Blade: 0.15 m Width of Blade: 0.12 m Impeller above vessel floor: 0.6 m

40 Lower impeller clearance: 0.6 m Upper impeller clearance: 1.8 m

Electrodialysis (Ready Made). Function: Provision for recovery of sulphuric acid from the two-stage hydrolysis process. Unit Model: Model 5 by Beta Control System Inc. Capacity: 1000-7000 gal per day Dimensions: Immersion exchangers: 1.3 m2 Reactor Tank: 1.8 x 1.5 x 1.5 m Settler Tank: 1.3 m diameter

Main Fermenter (Stirred Tank Reactor). Function: Production of Industrial Alcohol by Fermentation Type of Material: Carbon Steel No. of Units: 5 Operation: Batch Volume per unit: 755.49 m3 Dimension: Diameter: 7.83 m Height: 15.66 m Working Pressure: 443.49 kPa

41 Type of Head: Torispherical Depth of Dished Bottom: 1 meter Wall Thickness: 0.0237 m Head Thickness: 0.0259 m Width of Baffle: 0.6525 m Height of Baffle: 15.66 m No. of Impellers: 2 Impeller Diameter: 2.61 m Length of Blade:0.6525 m Width of Blade: 0.522 m Impeller above vessel floor: 2.61 m Lower Impeller Clearance: 2.61 m Upper Impeller Clearance: 11.11 m

Pre-fermenter. Function: For the preparation of yeast before it enters the main fermenter No. of Units: 3 Type of Material: Carbon Steel Volume per unit: 75.55 m3 Dimension: Diameter: 3.64 m Height: 7.28 m Wall thickness: 0.0121 m

42 Width of Baffle: 0.3033 m Height of Baffle: 7.28 m No. of Impellers: 2 Length of Blade: 0.3033 m Width of Blade: 0.2426 m Impeller above vessel floor: 1.2133 m m Lower Impeller Clearance: 1.2133 m Upper Impeller Clearance: 5.52 m

Culture Vessel. Function: Preparing of the yeast cultures Type of Material: Carbon Steel

3rd Culture Vessel. No. of Units: 1 Volume of Vessel: 75.55 m3 Diameter of Vessel: 3.64 m Height of the Vessel: 7.28 m

1st and 2nd Culture Vessel No. of Units: 1 Volume of Vessel: 7.56 m3 Diameter of Vessel: 1.69 m

43 Height of the Vessel: 3.38 m H= 2(1.69) = 3.38 m

Bd-95 Disk Stack Centrifuge (Ready Made). Function: To separate the dead yeasts cells and suspended solids present in the fermented solution. Type of Material: Stainless Steel 1.4418 49 No. of Units: 1 Throughput capacity (max): 60 m3/hr Bowl Speed: 4,300 rpm Bowl Volume: 66 L Sludge Space: 17 L Motor Speed: 1,821 rpm Motor power installed: 60 kW

Neutralization. Short Retention Time Clarifier Function: For the neutralization of the acid-sugar solution Type of Material: Type 304 Stainless Steel No of Units: 1 Capacity: 462,694.28 kg/day Volume of tank: 555.2331 m3 Dimension:

44 Height of tank: 8.9083m Diameter of Tank: 8.9083m Width of Baffle: 0.7424 m Impeller above vessel floor: 2.9694 m Impeller Diameter: 2.9694 𝑚 Length of Blade: 2.2271 m Width of Blade: 1.7817 m Operating Temperature: 30 oC

Cooling Jacket for neutralization. Cooling Fluid: Water Height of Jacket: 8.55m No. of spirals: 15 Mass flow rate of water: 2611.4 kg/hr Spacing between jacket and vessel wall: 0.3m Pitch: 0.5938 m Cross sectional area of channel: 0.17814m2 Length of channel: 391.807 m

Distillation. Function: To separate ethanol from the fermented beer. Type: Bubble Cap Tray Distilling Column Capacity:

45 No. of Units: 1 Height of Tower: 28.05 𝑚 Diameter of Tower: 1.87 m Tray Spacing: 0.5 No. of Stages: 11 stages (including reboiler) Feed Tray: 8th tray

Condenser. Function: To condense the vapor containing by 95% volume ethanol. Materials of Construction: Carbon steel except for plates No. of units: 1 Materials of Construction for the plates: 304 Stainless Steel Dimensions: Area: 128.55 m2 Length of tubes: 8m Diameter of tubes: 7

Outside diameter: 8 𝑖𝑛 =22.23mm Inside diameter: 0.652 in = 16.56mm Surface area of one tube = 0.5587 m2 Number of tubes: 230 Pitch: Square pitch at 27.79 mm Bundle Diameter: 537.04 mm No. of tubes in Center row: 19

46 Reboiler. Function: To generate vapors in the bottoms which are returned to the column. No. of Units: 1 Materials of Construction: Carbon Steel Materials of Construction for Tube: 317 Stainless Steel Type: Kettle Type (Shell and Tube) Dimensions: Area: 21.56 m2 Nominal length (One U tube): 10 m Number of U tubes: 46 Outside Diameter: 50 mm Inside diameter 45 mm Pitch: Square pitch at 62.5 mm Bundle diameter: 0.57m Shell diameter: 1.14m Liquid level from base: 1 m Freeboard: 0.14 m

Molecular Sieve Dehydrator. Function: To further remove the water in the water-ethanol solution of the distillate No. of Units: 1 Capacity: 48,580.8 kg/day = 48.3333 kmol/hr

47 Type of Material: Carbon Steel Type of Vessel: Pressure Swing Adsorption Height of Vessel: 3 m Diameter of Vessel: 1 m Absorbent Used: Zeolite 3Ǻ Pore Size: 3Ǻ Moisture Adsorption Capacity: 20% Pressure: 25 atm max with 3.673 atm H2O partial pressure 2 atm min with 1.90 atm H2O partial pressure

Storage Tanks. Mango Seed Kernel (MSK) Powder Storage (Ready-Made). Function: Will be used in the storage of mango seed kernel powder Type of material: Stainless Steel No. of units: 2 Capacity: 200 tons Tank Diameter: 3.6 m Tank Height: 13.6 m Total Height: 18.6 m

48 Ethanol Storage Tank. Function: Serves as a container for the 99.99% ethanol from the molecular sieve dehydration section for the whole day production. The product will be stored for several days until distributed to the loading trucks. Number of units: 3 Type of Material: Carbon Steel Capacity (per unit): 175.933 m3 Diameter of the tank: 4.47 m Height of the tank: 11.175 m

Hydrolysate Storage Tank. Function: To store the hydrolysate produced from the acid hydrolysis process Volume: 118.36 m3 Diameter: 4.49 m Height: 7.48 m

70% H2SO4 Storage Tank. Function: To store the 70% blend of sulphuric acid which will be used in the 1st stage hydrolysis Number of units: 1 Type of Material: Carbon Steel Capacity: 477.035 m3 Diameter of the tank: 7.14 m

49 Height of the Tank: 11.9 m

30% H2SO4 Storage Tank. Function: To store the 30% blend of sulphuric acid which will be used in the 2nd stage hydrolysis Number of units: 1 Type of Material: Carbon Steel Capacity: 162.71 m3 Diameter of the tank: 4.99 m Height of the Tank: 8.32 m

H2SO4 Recovery Tank. Function: To store the recovered sulphuric acid from electrodialysis Number of Units: 1 Type of material: Carbon Steel Capacity: 363.6 m3 Diameter of the tank: 6.52 m Height of the tank: 10.87 m

Water Treatment Plant. Anaerobic Digester. Function: Anaerobic digestion is a process in which microorganisms break down organic materials into methane (CH4) and carbon dioxide. This is accomplished in

50 the absence of oxygen therefore the anaerobic digester tank is capped to prevent oxygen from coming in and to capture the methane and carbon dioxide produced. The produced methane will be fed in the boiler for fuel consumption while the carbon dioxide is sold to bottling companies. Number of Units: 3 Type of Material: Carbon Steel Capacity: 390 m3 Diameter of tank: 6.92 m Height of tank: 10.38 m Impeller Diameter: 2.31 Height of impeller from ground: 2.31 m Width of Baffle: 0.5775 m No. of Impellers: 2 Length of Blade: 0.5775 m Width of Blade: 0.462 m Lower Impeller Clearance: 2.31 m Upper Impeller Clearance: 6.92 m

Process Water Tank. Function: To store the groundwater from the source that will be used in the process Number of units: 1 Type of material: Carbon Steel Diameter of the tank: 3.25 m

51 Height of the tank: 6.5 m

Demineralized Water Tank. Function: To stock the demineralized water after the reverse osmosis process Number of units:1 Type of material: Carbon Steel Capacity: 95m3 Diameter of the tank: 3.93 m Height of the tank: 7.85 m

Clarifier. Type: Circular Clarifier Material of Construction: Carbon Steel Operating Conditions Suspended Solids