ASI PP Operating Manual

8/12/2019 ASI PP Operating Manual

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AUDUBON SUGAR INSTITUTE

CANE-TO-SYRUP PILOT PLANT

OPERATING MANUALUnit Operations Laboratory Edition

Shivkumar Bale

AbstractBackground, Operations Concepts, Startup and Shutdown and Experimental Protocols


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Operating Manual

1. Overview of Cane Sugar Production1.1 General

Sugar is one of the dominant products in the agricultural sector and its global

production has increased linearly from 100 million tons in 1988 to more than 165 million

tons in 2008/09 [1]. Sugar is also known as sucrose, which belongs to the family of

saccharides. Saccharides are naturally occurring carbohydrates with the general chemical

formula CnH2nOn. Glucose is the simplest saccharide, a monosaccharide with the formula

C6H12O6. Sucrose is a disaccharide, C12H22O11, made up of two glucose molecules. Plants

produce saccharides through photosynthesis the process of combining carbon dioxide

and water to generate saccharides and oxygen, with sunlight as the energy source.

2 2 6 12 6 2

Glucose

6 6 6SunlightCO H O C H O O (0.0)

2 2 212 22 11

Sucrose

12 11 12SunlightCO H O OC H O (0.0)

Sugar is produced from plants like sugar cane and sugar beet. Sugar cane accounts for

approximately 70% of the global sugar production, whereas remaining 30% is produced

from sugar beets [2].

This manual focuses on sugar production from sugar cane. Much of the general

information and process description in the remainder of this section is a condensation of

material from United States Environmental Protection Agency documentation on sugar

cane processing [3].

1.2 Sugar Cane ProductionSugar cane is a tropical grass, which rather looks like a bamboo cane, where the

sucrose is stored in its stem. Sugar cane prefers strong sunlight and abundant water for


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its satisfactory growth. Sugar cane is a group of Saccharum species and its species

include S. officinarum, S. spontaneum, S. barberiand S. sinense. The cane can grow up

to 5 metres tall depending upon the species, whereas it can reach its maturity between

about 10 and 22 months depending upon the local climatic conditions [4]. The local

conditions also dictate the cane yields, which ranges from 50 to 120 x 103

kg/hectare/year [5, 6]. The sugar content of a mature cane depends upon the species, the

season and the location; however, typically it is 10% by weight. There are two methods

to harvest sugarcane: hand cutting and mechanical harvesting. If the land is flat, the

mechanical harvesting has been used for several years; however hand cutting is the most

common method. The sugar cane is different from most crops because they can regrow

after harvesting, if the roots are kept undisturbed. This cycle of regrowing the plant and

cropping it, is known as ratooning, and the plant lasts many cycles until it is worn out.

The number of cycles depends upon the vigor of the cane and the growing location.

The refined (white) sugar is produced from sugar cane in two stages. In the first

stage, the raw sugar, which is also known as cane sugar, is produced from sugar cane in

a cane sugar mill. The process flow diagram for cane sugar production is shown in

Figure 1. In the second stage, the cane sugar is refined to white sugar in a sugar refinery.

In U.S., the sugar cane is produced, harvested and processed through the first stage in

four states: Florida, Texas, Louisiana and Hawaii. The second stage is carried out in

eight states: Florida, Texas, Louisiana, Hawaii, New York, California, Maryland and

Georgia [3].

In cane sugar production, the other products are bagasse, molasses and filter cake.

Bagasse is the fibrous residue of sugarcane after milling process and it is a very high


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value by-product. It can be used in numerous ways, however in the cane sugar industry it

is used as an energy generation source by burning it in boilers. Molasses is the runoff

syrup after the final step of crystallization, from which no additional sugar can be

extracted. There are two forms of molasses: edible and non-edible (blackstrap). The

edible molasses is used as blends with maple syrup, inverted sugars, or corn syrup,

whereas the non-edible molasses is mainly used as an animal feed additive, however it is

also used to produce ethanol, compressed yeast, citric acid and rum. The filter cake

(filter mud) is the filtration residue of the mud, which is obtained from the clarification

process. The filter cake is used as an animal feed supplement, fertilizer and source of

sugarcane wax [3].

1.3 Sugar Cane ProcessingAfter harvesting, the cane is transported to the mill. In the mill, the cane is

unloaded, cleaned and prepared for the extraction of the juice. The preparation requires

the cane to be cut into small pieces, shredded and crushed. Thus, the preparation step

involves knives, a shredder and a crusher. This step is carried out to break the hard

structure of the cane and make the juice readily available for the extraction. After

preparation, the cane is passed through a multiple sets of three roller mills for the

extraction of juice. This step is known as milling or grinding. The process flow diagram

for milling is shown in Figure 2. As per requirement, the four, five and six roller mills

are also available for milling. Conveyors are used to transport the cane from one mill to

other, and to enhance the extraction, the water or the thin juice is sprayed on the cane

before it enters the next mill. This technique is known as imbibition (Figure 2). In

imbibition, fresh water is sprayed on the cane before it enters the last mill, and then it is


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transferred from one mill to other until it reaches the second mill. Whereas, the cane

travels from the first mill to the last mill. The crushed cane exiting the last mill is known

as bagasse. The juice from the first two mills is filtered to remove large particles of

bagasse, and then it is clarified [3].

In the clarification process, the juice is treated with lime and heat. The lime

neutralizes the organic acids, and the temperature of the juice is raised to 95oC. Thus, a

heavy precipitate is formed, which settles down in the clarifier. The limed juice is

separated from the precipitate, which is also known as mud, by gravity or centrifuge. The

mud is filtered and the filter cake is rinsed. The clarified juice is preheated and then

transferred to the evaporation station. The evaporation station consists of a series of

evaporators and the employed method is known as multiple-effect evaporation. The

process flow diagram for multiple-effect evaporation system is shown in Figure 3. In

multiple-effect evaporation, the steam from a boiler is used to heat the first evaporator,

and the steam generated from the first evaporator is used to heat the second evaporator

and so on. The temperature decreases from first to last evaporator due to the heat loss.

Hence, to reduce the boiling temperature in subsequent evaporators, the pressure is

decreased. The raw sugar syrup exiting the evaporation station has 65% solids and 35%

water. From evaporation station, the syrup is transferred to the vacuum pans for

crystallization [3].

The process flow diagram for crystallization is shown in Figure 4. The purpose of

vacuum pans is to produce sugar crystals from the syrup. In the vacuum pan, the syrup is

boiled until it reaches the supersaturation stage. At this stage, the crystallization is

initiated by seeding the solution. The seeding is carried out by adding isopropyl


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alcohol, ground sugar, or sugar crystals from the process to the syrup. After seeding, the

mixture of liquor and sugar crystals, which is also known as massecuite, is further

evaporated in the vacuum pan until the final massecuite is formed. The massecuite from

the vacuum pan (called strike) is transferred to crystallizer to maximize the sugar

crystal extraction from the syrup. The massecuite (massecuite A) from the crystallizer is

centrifuged to separate the crystals from the mother liquor (molasses A). The crystals are

rinsed and the wash water is centrifuged from the crystals [3].

The liquor (molasses A) from the first centrifugal is reboiled in the vacuum pans

to form massecuite B. The massecuite B is discharged to the crystallizer and centrifuged

to separate raw sugar from the liquor (molasses B). The liquor separated from

massecuite B is reboiled to form a low-grade massecuite C. The massecuite C is

crystallized and centrifuged to separate a low-grade cane sugar, which is used for

seeding the solution or mixed with the syrup. The liquor (blackstrap molasses)

separated from massecuite C is a heavy, viscous material, which is used as a supplement

for cattle feed. The cane sugar from massecuite A and B are dried and cooled. After

cooling, the raw cane sugar is transferred to the packing bins and stored [3].


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Figure 1. PFD for cane sugar production. The dotted rectangle represents the PFD for the pilot

plant in Audubon Sugar Institute.

Weighing

Preparation

Cane

Milling

Clarification

Mixed Juice

Evaporation

Clarified Juice

Crystallization

Syrup

Centrifugal

Separation

Massecuite

Drying

Raw Sugar

Bagasse

Filtration Filter Cake

Water

Filtrate

Water

Final Molasses

1st& 2

ndMolasses

Audubon

SugarInstitute


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Figure 2. PFD for milling.

1stMill 2

ndMill 3

rdMill 4

thMill

Cane

FreshWater

Mixed Syrup

To Clarification

1stMill Juice 2

ndMill Juice

3rd

Mill Juice 4th

Mill Juice

Ba


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Figure 3: PFD for triple effect evaporation system.

Feed

Steam

Feed to 2nd

Eva . Feed to 3rd

Evap.

Product

Vapor Vapor

Condensate Condensate Condensate

VaporCondenser

P1 P

2

P3

1st

Evaporator2

nd

Evaporator3

rd

Evaporator

P = Pressure

P1> P

2> P

3

Condensate


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Figure 4. PFD for crystallization.

Vacuum Pans

Isopropyl Alcohol

And Ground Sugar(optional)

Crystallizer

Centrifugal

Water Wash

Cane Sugar

(A and B Massecuite)

C Massecuite Seeding Solution

Water

Wash

Water

Sugar

Crystals

Blackstrap

Molasses

Syrup

A and B

Molasses

A, B and C

Massecuite

Raw Cane Sugar

To Dryer

Water


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2. Biofuels Pilot Plant at the Audubon Sugar InstituteAt the Audubon Sugar Institute (ASI), a biofuels pilot plant has been constructed

and commissioned as part of the Sustainable Bioproducts Initiative (SUBI) [7]. This pilot

plant produces raw sugar syrup from sugar cane, part of an overall cane sugar production

process. The process flow diagram of the biofuels pilot plant at ASI is shown in Figure 1;

a photo of the pilot plant is shown in Figure 5. To produce raw sugar syrup, the sugar

cane is processed through the milling, clarification and evaporation stages of cane sugar

production. The syrup from the pilot plant is distributed to ASIs research and

manufacturing partners to make biofuels and bioproducts. The pilot plant is designed to

process one ton of feedstock per hour and to produce 300 pounds per hour of syrup.

Figure 5. Photograph of the Pilot Plant at Audubon Sugar Institute


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This operating manual will be divided into the process unit operations: (1) Milling

(2) Clarification and (3) Evaporation.

2.1 Milling2.1.1. Objective

The objective of the milling operation is to extract the juice from the sugarcane.

2.1.2. Basic Theory

The basic theory of the milling process is to squeeze the juice from the sugarcane by

applying pressure. Therefore, the cane is passed through multiple sets of three, four or

five roller mills. Water or thin juice is added to the bagasse after each mill to dilute the

contained juice and enhance the extraction. This technique is known as imbibition.

2.1.3. Principle of Operation

In ASI, the milling process consists of four mills in series and each mill has four rollers.

The process flow diagram for milling process in ASI is shown in Figure 2, and it is

similar to a countercurrent solid-liquid extraction (leaching). Pretreated cane enters the

first mill and bagasse exits the last mill. Fresh water is added to the bagasse entering the

last mill, and the juice from the last mill is added to the bagasse entering the preceding

mill, until it reaches the second mill. The dry milling is carried out in the first mill, and

the juice from the first and the second mill is pretreated and sent for clarification process.

2.1.4. Pretreatment

In ASI, the pretreatment for the milling process involves two sets of revolving knives, a

shredder and a magnet. The revolving knives cut the cane into small pieces and the

shredder tear the cane into shreds. The knives and the shredder help break the hard


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structure of the cane and make the juice readily available for extraction. The magnet is

used to separate broken or loose pieces of metal from the shredded cane.

2.1.5. Critical Variables

Sucrose content in the juice is the critical variable indicating the efficiency of extraction

in a mill. The efficiency of milling is expressed as sucrose in juice percent sucrose in

cane. The sucrose content in the juice of a mill varies with the pressure in the mill and the

extent of imbibition.

2.1.6. Startup and Shutdown procedures

- Start the master switch on MCC. MCC stands for motor control center, and it has both

manual and automatic provisions to start the motors in the pilot plant. In order to start a

motor automatically, a digital input signal is provided by the control panel to the MCC

panel. Control panel consists of PLC controllers.

- Open the seal water valves for all the pumps and maintain the seal water flow.

- Start the computers in the control room and click on the ASI icon. Ask lab coordinator

for the password to access the computers. The control cabinet is also located in the

control room.

- Equipment and process color representation: 1. Grey indicates the equipment is on and

working. 2. Green indicates the process reached the stable state. 3. Blue indicates the

process is in transition state. 4. Red indicates alarms.

- The milling operation is divided into two stages: 1. Preparation and 2. Milling. During

startup, start milling first and then preparation, whereas during shutdown, stop

preparation first and then milling.


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- Preparation is further divided into three sections: 1stRun/Stop magnet, discharge gate

and rolling equipment, 2ndRun/Stop conveyors, and 3rdEnable/Disable feed deck. During

startup, start in the order of 1st, 2nd, and 3rd, because 3rdsection depends on 2ndsection,

and 2nd section depends on 1st section. During shutdown, stop 1st section and then

everything stops.

- Similarly, the milling stage is further divided into three sections: 1 stRun/Stop mills, 2nd

Run/Stop intermediate carriers, and 3rdEnable/Disable pumps. The order of startup and

shutdown is similar to the preparation stage.

- There are three emergency stops: two automatic and one manual. Two automatic

emergency stops can be accessed through the computers in the control room, and one

each for preparation and milling stage. Click once on the emergency stop icon to stop and

then click once again to relieve it. The manual emergency stop is located on the panel in

one of the corners of the milling stage.

2.1.7. Process Control

Two types of controller are used in the milling operation: PID controller and on-off

controller. PID controller is used to control the weight at the feed deck and the flow rate

of the imbibition water. On-off controller is used to control the juice level in the juice

tank from each mill, the level of bagasse entering the first mill, and the steam valves

open/close time for rotary screen cleaning. VFD, stands for variable-frequency drive,

with soft starters is used to control the motor speed and torque of the pumps by varying

motor input frequency and voltage. Rotation sensor is used to indicate the condition of

the pump (running or stopped).


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Figure 6. Photograph of the preparation stage (above) and milling stage (below) in the

milling operation at Audubon Sugar Institute.

2.2 Clarification2.2.1. Objective

The objective of the clarification operation is to remove both soluble and insoluble

impurities from the raw juice.

2.2.2. Basic Theory

The basic theory of the clarification process is to use lime and heat as the clarifying

agents. The raw juice from the milling process is acidic and turbid. Lime neutralizes the

organic acids and forms insoluble lime salts. The juice is heated to boiling or slightly

above, which helps to coagulate albumin and varying proportions of fats, waxes, and

gums. The flocculent precipitate thus formed traps finely suspended materials of the

juice. The heavy precipitate, also known as mud, is separated from the clarified juice by

sedimentation.


In ASI, hot liming process is used to clarify the raw juice. As per the hot liming process,

the juice is heated to 96oC and then the milk of lime is added, to precipitate the certain

colloids of the juice due to heat and pH. The advantages of this process are faster settling

rate, less mud volume, better turbidity level, and better color at 420 nm. A polymer

flocculent is also added to the limed juice. The main purpose of a flocculent is to increase

the clarity of the clarified juice, but it also improves flocculation, increases settling rate,

reduces mud volume, and decreases sucrose in cake. The treated juice is sent to the


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settling tank, also known as clarifier, where the mud is separated from the clarified juice

by gravity.

2.2.4. Pretreatment

According to the pretreatment to the clarification process, the raw juice from the mills is

passed through a rotary screen, which is a high quality filter for solid-liquid separation, to

remove additional fiber from the juice. This pretreatment improves clarifier capacity,

increases clarity of the juice, and gives a denser mud.


Increase in sucrose content between raw juice and clarified juice, is the critical variable

indicating the efficiency of the clarification process, whereas the pH is the critical

variable dictating the efficiency.

2.2.6. Startup and Shutdown Procedures

- Switch on the main power supply for clarification-evaporation skid.

- Switch on the MCC for the skid.

- Open the drain valve by two turns to drain the condensate.

- Open the main steam valve and close the drain valve.

- Open the seal water valves for all the pumps and maintain the seal water flow to 2 gph.

- Start the laptop in the control room and click on the PAC Display Runtime Professional

icon. Choose Clarification tab in the pop-up window. The control cabinet is located

within the MCC for the skid.

- Equipment and process color representation: 1. Green indicates the equipment is on and

working. 2. Red indicates the equipment is off.

- Start the main steam system on the control panel, and then start the mixed juice mixer.


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- Wait until the level in the mixed juice tank reaches 50%, then start the clarifier/heater

system on the control panel.

- In order to shutdown, wait until the mixed juice tank is empty and then stop the

clarifier/heater system on the control panel. In case of emergency shutdown, simply stop

the clarifier/heater system and the main steam system on the control panel.

- Equipment being controlled has both manual and automatic provisions. While under

control, equipment is in automatic mode; but if one needs to override an action, the

equipment should be in manual mode and then the necessary changes should be made.


PID controllers are used in the clarification operation. It is used to control the level of the

mixed juice in the mixed juice tank, the main steam pressure, the exit temperature of the

mixed juice through the mixed juice preheater, and the pH of the clarifier.

Figure 7. Photograph of the clarification operation at Audubon Sugar Institute


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2.3 Evaporation2.3.1. Objective

The objective of the evaporation operation is to concentrate the juice by evaporating

water.

2.3.2. Basic Theory

The basic theory of the evaporation process is to concentrate a non-volatile solute from a

solvent - mostly water - by difference in their boiling point. An evaporator consists of a

heat exchanger to boil the solution and a separator to separate vapor from the boiling

liquid. The energy consumption of the evaporation process is significant; therefore a

multiple-effect evaporation system is typically employed to reduce the energy cost. In

multiple-effect evaporation, the vapor generated in the first effect is used as the heat

source for the second effect.


In the biofuels pilot plant, a triple-effect evaporator with forward feed is employed in the

evaporation process. The process flow diagram for this triple-effect evaporation system is

shown in Figure 3. In a forward feed design, the preheated clarified juice enters the first

effect and the syrup is withdrawn from the third (and last) effect. The juice and the steam

flow parallel to each other from one effect to another. Each effect consists of a plate-type

heat exchanger and a vapor separator. Since the vapor from each prior effect is used to

heat the next effect, the pressure is reduced in each subsequent effect to operate at lower

boiling temperature. Indeed, the last effect is operated under vacuum.


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2.3.4. Pretreatment

The clarified juice is heated before entering the triple-effect evaporator to increase the

efficiency of the evaporation process and minimizes the thermal shock to the

components. In the ASI biofuels pilot plant, preheating is carried out in a plate-type heat

exchanger.


The total mass of water evaporated is the critical variable indicating the efficiency of the

evaporation process. The efficiency of an evaporator is expressed as the total mass of

water evaporated with respect to the total mass of steam supplied. The liquid level in

vapor separators is the critical variable in dictating the efficiency of the evaporation

process, because the separator needs air space in the chamber to be effective.

2.3.6. Startup and Shutdown Procedures

- To access the evaporation window through the clarification window on the control

panel, just click the To Evaporator tab on the clarification window.

- Equipment and process color representation: 1. Green indicates the equipment is on and

working. 2. Red indicates the equipment is off.

- When the level in the clarified juice tank reaches 50%, start the evaporator system on

the control panel.

- In order to shutdown, wait until the third evaporator is empty, and then stop the

evaporator system on the control panel. Meanwhile dont leave the pre-heater, first and

second evaporator empty, pass water through them by opening water valve on the

clarified juice tank. In case of emergency shutdown, simply stop the evaporator system

and main steam system on the control panel.


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- Equipment being controlled has both manual and automatic provisions. While under

control, equipment is in automatic mode; but if one needs to override an action, the

equipment should be in manual mode and then the necessary changes should be made.


PID controllers are used in the evaporation operation. It is used to control the main steam

pressure, the exit temperature of the clarified juice through the clarified juice preheater,

the flow rate of the pre-heated clarified juice, the level of the juice in the first vapor

separator, the level of the juice in the second vapor separator, the flow rate of the juice

through the third vapor separator (before the brix is achieved), the level of the juice in the

third vapor separator (after the brix is achieved), the pressure in the third vapor separator,

and the level of the condensate in the vacuum condensate tank.

Figure 8. Photograph of the evaporation stage at Audubon Sugar Institute


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2.4 Minimum Safety Regulations2.4.1. Authorization

- Each student must read and understand the minimum safety regulations section of this

document, and sign and submit the statement of understanding and compliance form (see

Appendix B) to the pilot plant coordinator before working in the facility.

- Each student must receive instructions on using the assigned equipment prior to

beginning any work. They must also fill out Job Safety Analysis Form in order to be

trained on the specific hazards of their equipment before to be allowed to work. Job

Safety Analysis Form can be accessed by following the link:

http://www.uolab.lsu.edu/documents/JSA_Form.pdf

- Only certified forklift operator is allowed to use forklift for feeding sugar cane.

2.4.2. Intent

- The intent of minimum safety regulations is to protect students from the potential

hazards of working in a pilot plant and promote safe practices.

2.4.3. Access

- The schedule for students to access the pilot plant would be prepared by the pilot plant

coordinator before the start of a semester. On the scheduled date, the pilot plant facility

would be available from 8 am to 4pm and the work should be finished within the time

frame. Students must always work in groups, and not allowed to work in the pilot plant

during evenings, holidays, or weekends without permission and supervision.
http://www.uolab.lsu.edu/documents/JSA_Form.pdfhttp://www.uolab.lsu.edu/documents/JSA_Form.pdfhttp://www.uolab.lsu.edu/documents/JSA_Form.pdf


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2.4.4. Services and Equipment Usage

- Any equipment must be operated only after receiving proper instructions from the

coordinator.

- Proper use of valves is very important in operating a pilot plant. There are different

types of valves and one must receive instructions to open, close or adjust a valve before

using it.

- Students work may involve use of services such as: cold and hot water, industrial

steam, electricity, vacuum and compressed air. Students must avoid spraying water on

electrical outlet and check carefully for shredded cord or loose connections. If noticed,

contact the pilot plant coordinator immediately. Steam lines are under high pressure and

they are common dangers in a pilot plant. Students must not operate steam lines and the

coordinator would be available to perform steam line operations.

2.4.5. Personal Gear

- Safety Glasses and Helmets: Students must always wear safety glasses and helmets in a

pilot plant. Full face shield should be worn if the procedure dictates during chemical

transfer and handling operations.

- Footwear: The wet floors of the pilot plant can be extremely slippery. Non-skid shoes

are highly recommended. Sandals and open-toed shoes are prohibited.

- Clothing: Students must wear long pants in the pilot plant and no loose clothing. Shorts

or skirts are prohibited. A lab coat should be worn if procedure dictates (e.g., during

chemical transfer).

- Insulated Gloves: Students must wear rubberized insulated gloves while working with

steam or chemicals.


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- Others: Students must wear their hair in such a manner that it does not interfere with

the work. Jewelry, watches and rings should not be worn in the pilot plant.

2.4.6. Chemical Handling/Storage

- The instructions about chemical handling/storage must be obtained from the appropriate

Material Safety Data Sheet (MSDS), container label, or the coordinator.

2.4.7. General Safety Procedures

- Smoking, eating, drinking, or chewing gum is not allowed in the pilot plant.

- If you notice someone not following the safety procedures, contact the pilot plant

coordinator immediately.

- In case of an accident involving injury:

- One or more persons should attend the needs of the injured person.

- Another person, in case of a serious accident, should call the ambulance dial 911,

and immediately notify the injury to the pilot plant coordinator.

- First aid kit (location ?)

- Fire extinguisher (location ?)

- Safety shower and eye wash station (location ?)

- Each group of students is responsible for the clean-up of their assigned equipment

throughout the cycle, in order to prevent the slip/trip/fall hazard. Sample containers must

be cleaned/properly disposed at the end of the cycle. Avoid spraying water on the

electrical outlet, and completely disconnect the equipment from the electricity before

cleaning it.

- Do not insert hands, fingers or any utensils in any equipment while it is operating or

even plugged in.


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- Think before you act, to prevent an accident for happening.

2.4.8. Miscellaneous Information

- Contact information of the pilot plant coordinator

3. Protocols

3.1. Process Protocols

3.1.1. Protocol for estimation of the absolute (1stMill) juice flow rate

- Switch off the juice pump #1, and check if the valves R1 and C1 are closed.

- Get a stopwatch and note the level in the juice tank # 1. At the very same moment, start

timing.

- Wait until the level in the juice tank # 1 is increased by 5% and then stop timing.

- Note down the time in the stopwatch and calculate 5% of the volume of the juice tank #

1.

- The absolute (1stMill) juice flow rate is 5% of the volume of the tank divided by the

time needed to raise the level of the tank by 5%.

- The above procedure should be repeated several times, in order to get a set of flow rate

measurements. The variation between several measurements taken in succession will give

an indication of the accuracy of the results.

- Instead of using 5% of the volume of the tank to calculate the flow rate, one can use any

percent of the volume of tank as per convenience.

- During flow rate calculations, make sure the juice tank # 1 doesnt overflow, and after

calculations, switch back on the juice pump # 1.

3.1.2. Protocol for estimation of bagasse flow rate

- Locate the end of the final bagasse conveyor, and get a stopwatch and a drum.


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- Place the drum under the end of the final bagasse conveyor and at the very same

moment, start timing.

- Fill the drum for a fixed amount of time and then stop timing. Dont let the drum

overflow during calculations.

- Note down the time in the stopwatch and weigh the drum.

- The bagasse flow rate is the weight of the drum divided by the time in the stopwatch.




3.1.3. Protocol for estimation of the time constant of the pH system

- Click the TRENDS tab on the control panel.

- Check if the pH is stable, and then increase the speed of the M.O.L. tank pump by 5%

- Monitor the change in the pH of the system.

- Once the pH is stable, decrease the speed of the M.O.L. tank pump by 5% and monitor

the pH until it is again stable.

- Then, extract the data and calculate the time constant of the pH system by using the

software.

3.1.4. Protocol for estimation of clarifier flow rate

- Note the level in the clarified juice tank and the flow rate of the pre-heated clarified

juice.

- If the level in the clarified juice tank is constant, then the clarifier flow rate is equal to

the flow rate of the pre-heated clarified juice.


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- If the level in the clarified juice tank is increasing, then note down the level, get a

stopwatch and at the very same moment, start timing.

- Wait until the level in the clarified juice tank is increased by 5% and then stop timing.

- Note down the time in the stopwatch and calculate 5% of the volume of the clarified

juice tank.

- Then divide the 5% of the volume of the tank by the time needed to raise the level of the

tank by 5%, in order to calculate the differential flow rate.

- The clarifier flow rate is the flow rate of the pre-heated clarified juice plus the

differential flow rate.

- If the level in the clarified juice tank is decreasing, the procedure is similar to that of

increasing level, but the clarifier flow rate is the flow rate of the pre-heated clarified juice

minus the differential flow rate.




3.1.5. Protocol for examination of strainers deposits

- Protective gear should be worn while operating the strainers, since clarified juice is at

high temperature.

- Pay close attention to the four valves V1, V2, V3 and V4 around two strainers S1 and

S2.

- Two out of the four valves would be closed because only one strainer is used at a time.

Open the closed valves and now, the juice is flowing through both the strainers.


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- Close the valves around the strainer, which needs to be examined. Close valve V1 and

V2 for strainer S1, whereas close valve V3 and V4 for strainer S2.

- Slowly loosen the lid in order to bleed the pressure. Open the lid and then remove the

strainer basket.

- Collect the deposits from the strainer basket for further examination.

- Put the strainer basket back in to the strainer and close the lid. Make sure the lid is

closed tightly.

- Again open all the four valves around the two strainers, so the juice can flow through

both the strainers.

- Keep the two valves open, around the strainer just examined and close the other two

valves.

3.1.6. Protocol for estimation of the mixed juice flow rate

- Switch off the mixed juice pump, and check if the valves M1 and M2 are closed.

- Get a stopwatch and note the level in the mixed juice tank. At the very same moment,

start timing.

- Wait until the level in the mixed juice tank is increased by 5% and then stop timing.

- Note down the time in the stopwatch and calculate 5% of the volume of the mixed juice

tank.

- The mixed juice flow rate is 5% of the volume of the tank divided by the time needed to

raise the level of the tank by 5%.





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- During flow rate calculations, make sure the mixed juice tank doesnt overflow, and

after calculations, open valve M1 and switch back on the mixed juice pump.

3.1.6. Protocol for estimation of mud + condensate flow rate

- Locate the exit of mud + condensate flow to the dumpster, and get a stopwatch and a

bucket of known volume.

- Place the bucket under the exit of the mud + condensate flow and at the very same

moment, start timing.

- Wait until the bucket is full and then stop timing.

- Note down the time in the stopwatch.

- The mud + condensate flow rate is the volume of the bucket divided by the time

required to fill it.




3.2. Analytical Protocols

3.2.1. Protocol for estimation of % Brix

- Brix concentrations are measured using a lightweight and compact refractometer.

- Apply two to three drops of sample onto the prism, press the start key, and the % Brix is

displayed in seconds.

- Calibrationclean off the prism, add water, and press the zero key.

3.2.2. Protocol for estimation of Turbidity

- Collect a sample in a clean container. Fill the sample cell to the line. Take care to

handle the sample cell and cap it.


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- Hold the sample cell by the cap, and wipe to remove water spots and finger prints.

- Place the sample cell in the instrument cell compartment, and close the cell cover.

- Read and record the results.

3.2.3. Protocol for estimation of % Pol (Reference)

- Pol is estimated by using saccharimeter.

- The clarifying agent Octopol is added to the sample

- The sample is then allowed to stand briefly before filtering it through a funnel with a

filter paper into a beaker.

- When sufficient filtrate has been collected to rinse and fill the tube, the funnel with

filter paper can be removed.

- Rinse the tube twice with the filtrate.

- Fill the tube with the filtrate and make sure no air bubbles are entrapped in the sample.

- Place the tube in a saccharimeter and note down the reading.

- Measure the temperature of the sample before emptying the tube.

- Before measuring the Pol for another sample, rinse the tube twice with that sample.

- After measurements, wash the tube with distilled water and fill it with water.

- Calculation of % Pol juice

The pol is calculated by using Schmitzs table. For example, assume,

Brix % juice = 10, 59

Saccharimeter reading = 35, 85

Then from table, % pol juice = 8, 96

In order to use Schmitzs table, the brix measurement of the solution and the

saccharimeter reading must be obtained at the same temperature. If the temperatures

differ, then it will be necessary to adjust the refractometer brix for the temperature


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difference. The adjustment to be made is obtained from Table. For example, assume

the saccharimeter reading of 35, 85 was made at 27 oC, then

If brix % juice (at 20 oC) = 10, 59

the adjustment for 27 oC = -0, 42

and adjusted brix reading is therefore = 10, 17

From Schmitzs table, the % pol juice using a brix reading of 10, 17 and

saccharimeter reading of 35, 85 = 8,97.

3.2.4. Protocol to submit samples to ASI Lab for analysis.


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4. Literature Cited[1] J. Villadsen, "The sugar industrythe cradle of modern bio-industry,"Biotechnology

Journal, vol. 4, pp. 620-631, 2009.

[2] (2013, May 22).Learn How Sugar Is Made. Available:

http://www.sucrose.com/learn.html

[3] "AP 42 - Compilation of Air Pollution Emission Factors - Sugarcane Processing," vol. I,

5th ed: Office of Air Quality Planning and Standards, Office of Air and Radiation, U.S.

Environmental Protection Agency, 1997.

[4] O. D. Cheesman,Environmental impacts of sugar production: the cultivation and

processing of sugarcane and sugar beet. Wallingford: CABI Publishing, 2004.

[5] A. P. Ruschel, "Report of the work group on sugarcane,"Plant and Soil, vol. 67, pp. 395-

397, 1982.

[6] P. P. Dua, "Sustainable Energy Supply in Asia - Chapter 18: Sustainable Energy Systems

for Rural Areas," inProceedings of the International Conference, Asia Energy Vision

2020, New Delhi, India, 1996, p. 639.

[7] R. Bogren. (2013, May 29).AgCenter biofuels pilot plant commissioned in La. Available:

http://www.lsuagcenter.com/en/crops_livestock/crops/Bioenergy/biofuels_bioprocessing/

subi/plant/AgCenter-biofuels-pilot-plant-commissioned-in-La-.htm
http://www.sucrose.com/learn.htmlhttp://www.sucrose.com/learn.htmlhttp://www.lsuagcenter.com/en/crops_livestock/crops/Bioenergy/biofuels_bioprocessing/subi/plant/AgCenter-biofuels-pilot-plant-commissioned-in-La-.htmhttp://www.lsuagcenter.com/en/crops_livestock/crops/Bioenergy/biofuels_bioprocessing/subi/plant/AgCenter-biofuels-pilot-plant-commissioned-in-La-.htmhttp://www.lsuagcenter.com/en/crops_livestock/crops/Bioenergy/biofuels_bioprocessing/subi/plant/AgCenter-biofuels-pilot-plant-commissioned-in-La-.htmhttp://www.lsuagcenter.com/en/crops_livestock/crops/Bioenergy/biofuels_bioprocessing/subi/plant/AgCenter-biofuels-pilot-plant-commissioned-in-La-.htmhttp://www.sucrose.com/learn.html


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Appendix A:

P&ID of the pilot plant.


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Appendix B:

STATEMENT OF UNDERSTANDING AND COMPLIANCE

Please sign and return this page to the Pilot Plant Coordinator before working in the facility.

I have read, understand and will comply with the Minimum Safety Regulations.

Print Name

Signature

Date

Documents

ASI PP Operating Manual