Mollasis BasedDistillary Project Report

Molasses BasedDistillary Project Report

ABSTRACT

 

  The main target at the distillery is to produce ethanol efficiently using molasses and grain (wheat and rice).  Ethanol is produced using fermentation (anaerobic). The microbe used for this purpose is Saccharomyces cerevisiae(yeast). Before fermentation inoculum is grown in a sterilized pre-fermenter (upstream). After the fermentation different constituents are separated using distillation (downstream). Then these constituents are subjected to blending by adding flavours. After it these different products are kept for maturation to have different tastes and colour according to the quality needed. The different products obtained are packed in bottles in bottling and packaging section. The spent media (after fermentation) is subjected to ETP (primary and secondary) section before it is being discharged in nearby fields where it is used as fertilizers by the farmers.

Acknowledgement

It is my pleasure and privilege to express my gratitude to my able and worthy Er. Kanchan Kumar (lecture) whose guidance inspired me to take up the training at the KHASA DISTILLARY CO.

 

I acknowledge my heartiest thanks to Er. P.k.yadav (Head) department of chemical engineering, Beant College of engineering and technology, Gurdaspur.

 

I am Thankful to Mr. Sandeep Sharma [AGM(P)] Mr. Raginder Kumar [Sr. Executive(HR)] & Gaurav Mahajan [Sr. Engineer (Process)] of KHASA Distillery CO , Amritsar.

 

With utmost sentiments of humanity, I am also Thankful to my respect parents, whose love and affection always sustained me in my efforts.

Contents

Certificate. a

ABSTRACT. b

HISTORY. 1

PRODUCTS AND BRAND NAMES. 2

FLOW CHART OF ALCOHOL PRODUCTION PROCESS(MOLASSES PLANT). 4

PROCESS DESCRIPTION FOR GAIN FLOUR PROCESSING.. 6

FERMENTATION UNIT. 9

DISTILLATION UNIT. 11

CONTINUOUS DISTILLATION.. 12

DISTILLATION IN KHASA DISTILLERY. 14

ANALYZER COLUMN.. 14

DEGASSIFYING COLUMN.. 14

RECTIFICATION COLUMN.. 15

ALDEHYDE COLUMN.. 15

E.N.A. COLUMN.. 16

Purification Column: 16

Exhaust Rectification Column: 16

BLENDING.. 18

BOTTLING.. 19

WASHING.. 19

SEALING AND LABELLING.. 19

BOTTELING SECTION.. 20

EFFLUENT TREATMENT PLANT (ETP). 21

UPFLOW ANAEROBIC SLUDGE BLANKET (UASB) REACTORS. 22

GAS HOLDING SYSTEM... 22

ANAEROBIC DIGESTION OF COMPLEX ORGANIC WASTE. 23

MAIN TESTS CARRIED OUT IN.. 24

CENTRAL LABORATORY. 24

TOTAL REDUCING SUGAR (TRS). 24

UNFERMENTABLE SUGAR (U. F.S). 25

MICROBIOLOGICAL TESTS. 26

Plating for wild yeast count. 26

Tests perform in effluent treatment plant: 26

B.O D (biological oxygen demand): 26

C. O. D CHEMICAL OXYGEN DEMAND) TEST. 27

TOTAL SUSPENDED SOLID (T.S.S). 27

GENERAL DESIGN CONSIDERATIONS. 29

SHELL AND TUBE FLUID VELOCITIES: -. 30

STREAM TEMPERATURES: 31

PRESSURE DROP: 31

FLUID PHYSICAL PROPERTIES: 32

BASIC DESIGN PROCEDURE AND THEORY. 33

FOULING FACTORS (DIRT FACTORS). 35

MEAN TEMPERATURE (TEMPERATURE DRIVING FORCE). 36

TUBE SIDE HEAT TRANSFER COEFFICIENTAND PRESSURE DROP. 37

HYDRAULIC MEAN DIAMETER. 38

LAMINAR FLOW... 38

COEFFICIENT FOR WATER: 39

SHELL SIDE HEAT TRANSFER AND PRESSURE DROP. 40

REFERENCES. 44

 

 

 

KHASA DISTILLARY

 

 

HISTORY

 

KHASA Distillery Company is a unit of Bhagat Industries Corporation Ltd. This company meant for manufacturing of Indian Made Foreign Liquor (IMPL) and Punjab Medium Liquor (PML).

British company Established this Distillery in 1898.It was renamed as Punjab Distillery in 1945.It become a part of Bhagat Industries Corporation Ltd in 1997.For some time being this industry was worked as a pharmaceutical factory. But due to some reason this factory was closed and works again as Bhagat Distillery Co.

 

LOCATION

Khasa Distillery Co. Is situated in a small village named as Khasa, which is on Amritsar Wagha Boarder National Highway. Factory is about 20K.M. from Amritsar bus stand.

Khasa Distillery is a big unit and is spread on 90 acres of Land. Effluent treatment plant, which is meant for the treatment of wastewater, is situated at the backside of the plant.

 

 

PRODUCTS AND BRAND NAMES

 

·       PUNJAB MEDIUM LIQUOR(PML)

 

Products Brands	Proof(degree)	Alcoholic contents(v/v)
Santra	50	28.55%
Pakeeza Rum	65	37,1%
Pakeeza zin	65	37.1%
Club whisky	65	37.1%
Rum	65	37.1%

 

·       INDIAN MADE FOREIGN LIQUOR(IMPL)

 

Products & Brands	Proof(Degree)	Alcoholic contents(v/v)
RC	75	42.8%
Antiquity	75	42.8%
Signature	75	42.8%

 

 

 

 

KHASA DISTILLARY COMPANY KHASA (AMRITSAR)

 Brief Description and Schematic Flow Diagram

 Molasses received from sugar mills stored in molasses storage tanks Molasses is pumped from storage tanks to process. Before processing its quality is checked for sugar contents Brix and pH etc. Molasses diluted with water to maintain 12-13 % sugar in diluted molasses. Yeast is propagated from lab to fermenter and after transferring yeast of fermenter, fermentation tank is filled Temperature specific gravity and pH is recorded at the time of set up which is normally 30 C 1085 and 4.8. After completion of fermentation in 12-16 hrs. Time alcohol % and residual sugar is checked. Fermenter temperature is maintained at 30-34 C and pH 4 5.

Fermented liquid termed as wash is sent to distillation plant Wash is boiled al 105 C and alcohol vapours are collected and rectified. Rectified spirit contains 94-96 % of alcohol Rectified spirit is redistilled for further purification and sent finally to receiving storage tanks/ware house. Purified spirit so produced is necked for its quality and reduced with D M water to desired strength of 42.8 % v for blending, colouring and adding essences. After completing blending/colouring process the liquor is sent to bottling, whisky/rum so blended is filtered with sparkler filter machine and ready to fill into washed bottles. While bottling all the packing quality are ensured and packed cases are stored in storage Godown for supply

 

 

 

FLOW CHART OF ALCOHOL PRODUCTION PROCESS(MOLASSES PLANT)

 

MOLASSES TANK                          OVERHEAD DILUTER

 

                PRE FERMENTER

 

              FERMENTATION VATS

 

             DISTILLATION PLANT

 

             REACTIFIED SPIRIT RECIVERS

 

           POT STILLS (FOR SPICING)

 

                     RECIVERS

 

                                   REDUCTION VATS WAREHOUSE BLENDING

 

BOTTLE                                  BOTTLING HALL (BOTTLING PURPOSE)

 

                 WASHING UNIT

               STORE

PROCESS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PROCESS DESCRIPTION FOR GAIN FLOUR PROCESSING

1.    FLOUR HANDLING:-

Grain Flour is lifted in buckled elevator and stored in hopper bins provided for buffer capacity for flour storage. The flour addition is mattered through a weigh feeder with load cell arrangement before transferring to the mixing tank for slurry preparation process.

2.    Slurry PREPARATION /LIQUIEFACTION :-

Grain flour is fed at controlled rate to mixing tank to an agitated slurry tank where some amount of water and enzyme stabilizing chemicals are added. A portion of liquefying enzyme is also added here. This slurry is then “cooked” in the cooker where high pressure steam at 7 bar (g) /127°C rapidly raises the slurry temperature. The mixture of slurry and steam is then passed through the holding coil which has several ”U” bends in series and sufficient capacity to provide the desired retention time at a given flow rate. The cooked mash is discharged to a flash tank. The cooking process, accomplished in the above manner, converts the slurry into a hydrated, sterilized suspension (as starch molecule is solubilised) and is therefore susceptible to enzyme attack for liquefaction.

The gelatinized mash from the flash tank is liquefaction tank where liquefying enzyme is added. Then the liquefied mash is cooked in slurry cooler to about 60°C.and transferred to partial pre-scarification tank where the scarifying enzyme is added. This process initiates the formation of sugar. The mash is then cooled and transferred to fermenter.

 

3.    SACCHARIFICATION AND FERMENTATION

YEAST PROPAGATION:-

Yeast seed materials are prepared in water cooled vessels by inoculating sterilized mash with culture yeast. Optimum temperature is maintained by cooling water. The content of the yeast vessel are then transferred to Pre fermenter.

The Pre fermenter are filled with mash and loaded with contents of the yeast vessel. The purpose of the aerated Pre fermentation is to allow time for the yeast cells to multiply and reduce the chances of contamination in fermenter. When the pre-fermenter contents are transferred to the main fermenter, the concentration of yeast cell is high enough to substantially reduce the lag time associated with yeast growth in fermentation.

 

4.    FERMENTATION

The purpose of fermentation is to convert the fermentable substrate into alcohol. To prepare the mash for fermentation, it may have to be diluted with water. The pH of the mash is adjusted to about 5.0 accomplished primarily by recycled slops (which also provides for nutrients) and by the addition of acid. Yeast is available in sufficient quantity to initiate fermentation rapidly and complete it within 54 hours.

 

AT the start of the cycle, the fermenter is charged with the contents of the pre-fermenter. Significant heat release takes place during fermentation. This is removed by forced circulation cooling in external heat exchangers to maintain an optimum temperature of 30°C.The recirculating pumps also serve to empty the fermenter into beer well. After the fermentersare emptied, they are cleaned with water and caustic solution and sterilized for the next batch.

The carbon dioxide evolved during the process is scrubbed to prevent ethanol emission by process water, which is taken to beer well.

The fermented wash is fed to primary distillation plant to produce rectified Spirit.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

FERMENTATION UNIT

 

FERMENTATION PLANT

DEFINATION:-

Fermentation is the process in which complex organic substance (molecules) is converted into simpler organic substance by action of enzymes secreted by the microorganisms.

FERMENTATION IN GENERAL:-

 The term fermentation is derived from the Latin verb fevered to bail thus describing  the appearance of the action of yeast on extract of fruits or malted grain or sugarcane molasses. The boiling appearance is due to production of CO2 bubbles caused by the anaerobic catabolism of sugar.

 Its biochemical meaning relates to the generation of energy by the catabolism of organic compounds

 For industrial microbiologists, the term fermentation is to describe any process for the production of product by the mass culture of a microorganism.

Alcoholic fermentation is the process in which sucrose and reducing sugars i.e. glucose and fructose are converted ethyl alcohol and carbon dioxide by the action of enzymes invert age and enzyme Secreted by ne microorganism “yeast”.

 

 

 

. C₁₂ H₂₂ O₁₁+H₂O                                         C₆ H₁₂ OC₆     +     C₆ H₁₂ O₆

(Sucrose)                          (Invertage)             (Glucose)        (Fructose)

 

•         H₁₂ O₆                                                        2C2 H5 OH + 2CO₂

(Glucose)                      (Zymase)           (Ethyl            (carbon dioxide)

                                                                     Alcohol)

 

One mole of glucose will yield two moles of ethyl alcohol 180gms Of glucose will yield 92gms Of ethyl alcohol Therefore 100gms Of glucose will yield 51 11gms Of ethyl alcohol.

Hence in obtaining maximum efficiency in the fermentation house, the sugar content of the molasses plays an important role.

 It has been calculated that one tone of fermentable sugars will yield theoretically 644 let’s of ethyl alcohol, but all the sugars cannot be converted into alcohol Some sugars get converted to products other than ethyl alcohol such as yeast cell biomass, glycerol and succinct acid This leads to decrease in ethanol yield A more realistic theoretical yield would be 95 % and good practical yield would be 90 % of the figure indicated in the equation.

 

 

 

 

DISTILLATION UNIT

TYPES OF DISTILLATION SYSTEM

BATCH DISTILLATION

  Until the introduction of the continuous still are the distillations had been carried out in pot stills using the batch distillation techniques? The simplest type of pot still is pot or kettle in which the fermented wash is heated so that its volatile constituents are driven off to be condensed in a cooling worm mind then collect in a receiver The bottom should be concave to the fire since this form is structurally stronger and exposes to a large heating surface while the curve surface assists draining though the discharge cock The convex upper surface of the still called the breast should be rather wider than the bottom From the middle of the breast, a pipe rises to a varying height and this is occasionally bubbled or commences in an expansion tapering to a narrow end like an inverted pear This up pipe is termed the head In the simple's form of still the head opens into a pipe (called the Lying pipe') leading direct to the condensing worm.

In order to prepare stronger and purer liquor is often advisable to fit between the still and the condensing worm 1) a doubler and 2 a rectifier The main function of the doublers is to arrest the acids & furfural armed Whereas rectifier purifies ethyl alcohol by partial condensation and rectification.

 

 

 

 

 

CONTINUOUS DISTILLATION

 A typical distillation column consists of a cylindrical tower arranged vertically which is subdivided into a series of stages by plates mounted horizontally in the tower. The feed plate is where the mixture to be distilled is continuously introduced into the column. This liquid flows across plate to a vertical down comer pipe, which permits the liquid to flow to plate below. This cross flow pattern continuous until the liquid exists at the base of the column. Heat is supplied to the column either by directly separating ne steam into the base of the column or by indirectly heating the liquid at the column base in an external caldaria or reboiler. This heat causes the liquid to boil and the resultant vapours to flow though the holes in the next higher plate. The vapours condensed and give up their latent heat to the liquid flowing across each plate and as a result liquid on each plate will boil. The vapours continue to flow upwards from plate to plate to the top of the column. At the top of the column the vapours pass through an external heat exchanger where they are condensed A portion of the condensed liquid is recycled back into the column as reflux, which increases the alcohol concentration in the column. The vapours can be totally condensed or a partial condenser or Dephlegmator can be used before a final condensed. The reflux flows counter currently from the top plate until it joins the liquid feed at the feed plate.

The plates below the feed plate are collectively known as stripping section' of a column because it is in this region that the more volatile components are stripped from the less volatile components. In the region above the feed plate the more volatile substances are concentrated and less volatile components are removed from the distillate. This area is referred to as the Rectifying section of a distillation column. The preheated fermented wash is introduced at the feed plate located near the top of the beer still (Analyzer cum degassing column). The base effluent or stillage contains the non-fermentable solids. Yeast cells and water. The aldehyde or heads purifying column is responsible for removing the highly volatile aldehyde and esters from the alcohol product. The primary purpose of a rectifying column is to remove water from the product distillate. A heads draw that contains 2 5 % of the feed flow rate is drawn from the condenser and the remaining condensed overhead vapours are returned to the column as reflux. The product is taken from a side draw about 3-5 plates from the top of the column. The fusel oil accumulates 3-4 plates above the u feed on the plate.

DISTILLATION IN KHASA DISTILLERY

 Here are two distillation plants of 45 KL/day capacity at a time one plant is in operation and the other is used as stand by the distillation plant consists of the following column.

·        Analyzer Column

·        Rectification cum Exhaust Column

·         Aldehyde Column ENA Column

 The whole of distillation completes in all these columns written above

 

DESCRIPTION ABOUT THE COLUMN

 

ANALYZER COLUMN

 In the Analyzer column there are 18 plates and 6 plates in the Analyzer column i e 18+6-24 Steam from the boiler of tank is given at the bottom of the column at 125 C and of 2 kg/cm2 pressure Feed entering from the top of column after passing through PHE The temperature of the feed entering the column. about 7 to 8 % v/v. which is processed to about 40 % at the time taking it out from the Analyzer spent wash coming from the bottom is also passed through PH.E and is sent back to the column along with wash feed product from the Analyzer column is drawn from 18^th plate highest product separate out and go to aldehyde column.

DEGASSIFYING COLUMN

Degasifying unit is above the Analyzer column It contain 6 plates diameter of Analyzer column is about 60 and the degasifying unit is of 48”dia. Degasifying unit is to remove the gases from the plant this solution is used for Analyzer column.

All the impurities are called as the fusel oil. That is to be separate in the form of the bubbles m a decanter as explained on the back paper hence it gel explains.

RECTIFICATION COLUMN

 There are about 44 plates in the rectification column and 12 plates in the exhaust column and 12 plates in the exhaust column; feed going into the column is about - 40 % v/v.

Product is tapped from the 41, 42, 43 plates and is send to the cooler The product obtained from the cooler is the ( R S ) is about 95 % v / v vapours coming out from the top is goes to the condenser, the reflux is send back to the column. Impurities are sent back to the column al about 79°C Bottom product of the rectification unit is goes to the exhaust column Steam is send the spend lees is obtained top of the exhaust unit is sent to the rectification column first plate at about 90°C.The alcohol vapour coming about at 72°C that is cooled to the 79°C. Product from the rectification column is drawn at 78. 3°from the plates

 

ALDEHYDE COLUMN

 

 This column contains 24 plates Wash or fermented mash is sot al the top for the degassifier column and the steam is feed al the bottom of the Analyzer column Alcohol from the top of Analyzer column goes to rectified column.

 Spent wash from the bottom goes to ETP for treatment.

Vapour from the tops of degasifies column goes to aldehyde column from where impure spirit is removed Pure spirit is desired from the top of rectifying column. Spent wash from the bottom of exhaust column is taken along with wash in the Analyzer. Impurities like higher alcohol are separated from the rectified spirit in the Analyzer column.

Rectified spirit is redistilled is hot still along with spices to get spiced country liquor. The liquor is taken to ware house for blending

 

E.N.A. COLUMN

·        It consists of two columns.

·        Purification Column.

·        Exhaust cum Rectification Column.

 

Purification Column:

This column contains about 42 plates. This column is used to purity the R.S alcohol R. S and demineralised water is added in it and esters are removed R.S feed is about 95 % v / v. impurities coming out of from the top are condensed and removed. Tapping of the purified product, steam is supplied at the bottom of the purification column.

Exhaust Rectification Column:

This column contains 70 plates feed from the top of the column is fed al 18^th plate and tapping of the product. ENA Is done at 64, 68, 67 plates Spent lees is obtained from the bottom vapour coming out from column are send to the condenser and are removed. Steam is supplied at the bottom n-propanol is tapped al 30 plates above the bottom. Aldehyde is also removed Methyl alcohol in ppm is left Finally ENA product is obtained.

 

  There are three columns-

1.     Rectification columns

2.      Analyser column

3.      Aldehyde column

Analyser Column

There are 18 plates in the Analyser column of 6 plates above in degasifying wind.

I: etherise total 18+6-24 plates in the analyser

Extra 3.7 volume of water has to be added, the diluted spirit now contain103. 7/100 or 1.307 be a factor when multiplied give the separate value contain in any other quantity of spirit of this strength.

BLENDING

Blending of spirits means the mixing of together two or more spirits of different strength.

Case 1 A strong spirit is to be lowered to a given strength. Find how many gallons of weak spirit must be added. Multiplied the volume of strong by the number of degrees by which it is to lowered and divided by the degrees of the weak spirit will be raised by mixing.

Case 2 A weak spirit is to be raised lo be given strength found how many gallons of a given strong must be added multiply the volume of the weak spirit by the number of degrees the strong spirit will be lowered by the mixing.

Case 3 A given volume of the intermediate strength is required. Find how many gallons each of a strong and weak spirit must be added. Multiply the required by the number of degrees the spirit will be raised by mixing and divided by the difference in proof degrees between weak spirit and strong spirit. The result gives the required volumes of strong spirit and the balance is gives the required volume of weak spirits.

 

 

 

 

 

 

 

 

BOTTLING

After the blending, the liquor is filled in the bottles both the glass and plastic bottles are used for filling the liquor.

Before bottling the washing of the bottles have to be done.

WASHING

Ø To clean the bottles.

Ø To remove the dirt and dust from the bottles.

Ø To remove labels from the bottles.

 

Washing of the bottles have to done automatically or semi automatically bottles purchased from the market and washed with the water. Water is sprayed with the pressure over the bottles and washed.

Soft water is used for washing the bottles. These bottles are sent to filing mechanised by conveyor.

Washing of the bottles for the brands is done semi-automatically. Tap water is used for washing In H2O, HCI, soap solution and steam is entered Bottles are washed with this solution and dust and labels are removed.

The machines with attached brushes are used to clean inside of the bottles. It is quite compulsory that at 25 % of new bottles are to be used for PMC (Punjab Made Liquor).

 

SEALING AND LABELLING

Sealing of the bottles is done with the machines, labelling is done both machine and manually. After labelling the bottles are packed and stored in godown.

 

BOTTELING SECTION

 

 

BOTTLES

 

                                                                                                           

 

 

 

ALOCHOL

 

FROM WEIR HOUSE                                     

 

 

 

 

                                                                                 

 

 

 

EFFLUENT TREATMENT PLANT (ETP)

 

 Every Fermentation plant unitizes raw materials, which are converted to a variety of product. Along of waste products typical waste material include unconsumed organic and inorganic matter microbial cells suspended solids. Waste cooling water, alkalis acids, water containing solvents human sewage. Until recent years it was possible to dispose of waste directly to the convenient area of land or into hard courts’ But legislations in all development countries now regular the discharge countries now regulate the discharge of liquid, solid or gaseous waste.

DETAILED DESCRIPTION OF THE ETP

 Effluent treatment plant consists of the following processes.

 

SPENT WASH HOLDING TANK

 The spent wash arrives at the tank by gravity. From the spent wash holding tank spent wash is pumped via heat exchanger to the buffer tank.

 

BUFFER TANK

Continuously the cooled spent wash pumped to the buffer tank. Where it is mixed with the recycled treated spent wash. In the buffer tank a temperature of 37°C to 4o°C and a pH to be 6.0 to 6.5 maintained.

 

The purpose of the buffer tank is for –

1.     Thoroughly mix the spent wash with the recycled Effluent.

2.    Control the pH and temperature.

3.    Make addition of nutrients.

UPFLOW ANAEROBIC SLUDGE BLANKET (UASB) REACTORS

 In these reactors the COD (chemical oxygen demand) removal and production of biogas plant take place. The influent enters at the bottom via special distribution System, which ensures good contact between influent and biomass. As the influent percolates up, organic matter is converted into methane and carbon dioxide by the biomass. At the top of the reactor the settlers separate the gas and biomass from the effluent the treated effluent overflows via gutters to the launder from where partly recirculate to the buffer tank and remaining sent for further treatment to secondary treatment plant.

GAS HOLDING SYSTEM

The biogas produced leaves at the top of the reactors via a gas heater from there it lows to foam or condensate trap. Since, the biogas is saturated with water at ambient temperature lower than 35 C, water will condense, which is removed here. The biomass contains some foam, which is also disposed of in this trap. From here the gas flows to the gas holder. The gas holder serves as a buffer to provide back pressure on the settle. The construction of the gas holder is of the floating dome type and has a water seal at the bottom. From the gas holder, gas blower transports the biogas to the boilers where the gas is burnt. A re-circulation line is provided so that the gas blower can also run continuously at decreased biogas production rates.

ANAEROBIC DIGESTION OF COMPLEX ORGANIC WASTE

 The anaerobic digestion of organic compounds is carried out by many different bacteria; generally three main groups are distinguished.

Ø Hydrolysing bacteria

Ø Acetogenic bacteria (acetate forming bacteria)

Ø Methanogenic bacteria (methane forming bacteria )

The first two steps, hydrolysis and acidogensis are performed by fermenting bacteria. They hydrolyse (split a molecule into a more fractions under uptake of water) dissolved and undisclosed polymers like fats, proteins and carbohydrates through action of exoenzymes into smaller units, which can be taken up by bacteria.

Because of the production of volatile fatty acids (VFA) the fermenting bacteria are also called acidifying or Acetogenic bacteria.

Acetogenic bacteria breakdown the products of acidifying bacteria to acetate, hydrogen and carbon dioxide

The Methanogenic bacteria convert acetate or hydrogen or carbon dioxide.

 The methanogens can be divided into two major groups, the acetate converting Acetotrophic bacteria and the hydrogen utilizing.Hydrogenotropicbacteria. A small group is able to use acetate and hydrogen +carbon dioxide as well as methanol.

 

 

 

 

MAIN TESTS CARRIED OUT IN

CENTRAL LABORATORY

 

CHEMICAL TESTS

TOTAL REDUCING SUGAR (TRS)

Principle: Sucrose in molasses after acid hydrolysis converts into glucose and fructose Glucose and fructose reduce Fehling’s solution and hence are called reducing sugar.

Diluted molasses solution is hydrolysed with HCl and it is titrated against Fehling’s solution. Copper present in Fehling’s solution is in form of cupric sulphate, which gets reduced to cuprous oxide by glucose and fructose, and glucose is oxidized to gluconic acid. Hence it is the red ox type of reaction. Amount of glucose and fructose required to reduce definite amount of copper in soxhlet solution is determined titrimetrically and reducing sugars are calculated.

PROCEDURE

•          Take 50 g of molasses in a flask and make up the volume to 500ml.Take 10ml from 500ml in a separate flask and add 10 ml of water and 5 ml concentrate HCl to it.

•          Keep the flask in water bath at 70° C for 5-7 minutes, then cool it and then add 3-4 drops of phenolphthalein and neutralize by adding NaOH. Cool again under tap water and make the volume up to 100ml.take this solution to burette.

•          Take 5 ml of Fehling solution A and Fehling solution B in conical flask and 20 ml water to it boil it for 2-3 minutes and add methylene blue as indicator and then titrated. This solution with molasses solution taken in burette.

•         End point of the titration is change of coloration from blue to brick red At this point note down the reading Divide the reading of burette with Fehling factor, which gives the final, result that is total reducing sugar.

 

Result

The value of total reducing sugar in molasses should be 38 % and in worth should be 12.1 %.

UNFERMENTABLE SUGAR (U. F.S)

 

This is the test to estimate that how much unfermented sugar is present in the molasses sample.

PROCEDURE

•         Take 20g of molasses in flask and add 100ml of water in it. Then add yeast powder. Pinch of urea, ZnSo₄, MgSo₄ to It and incubate at 37°C.

•         Then add 25ml of leading solution (10%) in it and up to 250ml of water and shake it and centrifuge at 3000pm for 2 minutes.

•         Take the 25 ml of supernatant and add 10ml deluding solution and titrated with Fehling solution A and B.

 

MICROBIOLOGICAL TESTS

 For microbial testing mainly plating is done Plating for total bacterial count Agar medium is used for the total bacterial count. Take 10 ml of media and take 10 ml of sample and inoculate this sample on agar plates and keep the plates in inverted position at 31°C for 24 hours.

Plating for wild yeast count

For wild yeast count lysine medium is used. Take 20 ml of medium and 1 ml of sample to be tested and sample is inoculated on to the lysine medium plates and plates are incubated for 24-37° C and then checked for the yeast growth.

Tests perform in effluent treatment plant:

 B.O D (biological oxygen demand):

To determine the organic matter in water BOD method is used which is a measure of quantity of oxygen required for oxidation of organic matter in water by microorganisms in a given time interval at a given temperature.

The method is as follows:

•         Aerate water for 2-3 hours. Then add 1ml per lire of each CaCl₂, FeCl₃, Mg SO, and phosphate buffer.

•         Take 1 ml of above sample and dilute it to 100ml. Then take 1-5ml from the diluted sample and add 300ml water to make total dilution 20,000 times.

•         Then titrations are performing. There is two types of titration one is immediate and other is after 3 or 5 days. In immediate titration add 2 ml of alkalized (ppt formation occur) then add 2ml of magnesium sulphate.

•         After 2 minutes add 2ml H₂SO₄. Dissolve it, on appearance of brick red colour. Take 203 ml of solution in separate flask and titrate it with of Sodium thiosulphate with starch indicator. End point is appearance of colourless solution.

 

Result

The BOD of spent wash should be 35000-45000mg/1.

C. O. D CHEMICAL OXYGEN DEMAND) TEST

C. O.D only few hours to Complete.

Procedure

•         The 20 ml of sample is taken and ad 10ml of potassium dithionate to it and add also ii ml of sulphuric acid. Then add silver sulphate and Mercuric sulphate and then reflux the solution for 2 hours.

•         Cool the solution and add 80 ml of water to it Titrate it Ferrous ammonium sulphate with ferric ion indicator .Ed point is appearance of green to brick red colour.

Result

COD of spent wash should be 80,000-10,0000mg/l.

TOTAL SUSPENDED SOLID (T.S.S)

Procedure

 Centrifuge the sample. Discard the supernatant and evaporate the remaining in oven at 105°C.This give the dry weight and give the value of total suspended solid.

Result

The value of total suspended solid should be 5000-10,000 mg/l.

PROJECT

ON

DESIGNING

OF

SHELL AND TUBE

HEAT EXCHANGER

USED

FOR

THE

PRODUCTION OF ALCHOL

 

GENERAL DESIGN CONSIDERATIONS

1. FLUID ALLOCATION: SHELL OR TUBES

Where no phase change occurs, the following factors will determine the allocation of the fluid stream to the shell or tubes.

1.1 CORROSION: - The more corrosive fluid should be allocated to the tube -side. This will reduce the cost of expensive alloy or clad components

1.2 FOULING: - The fluid that has the greatest tendency to foul the heat - transfer surfaces should be placed in the tubes. this will give better control over the design fluid velocity, and the higher allowable velocity in the tubes will reduce fouling. Also, the tubes will be easier to clean.

1.3 FLUID TEMPERATURES: - If the temperatures are high enough to require the use of special alloys placing the higher temperature fluid in the tubes will reduce the overall cost

 1.4. OPERATING PRESSURES: - The higher pressure stream should be allocated to the tube -side. Higher - pressure tubes will be cheaper than a high-pressure shell.

1.5 PRESSURE DROP: - For the same pressure drop ,higher - transfer coefficients will be obtained on the tube - side than the shell-side, and fluid with the lowest allowable pressure drop should be allocated to the tube -side

1.6 VISCOSITY: - Generally, a higher heat-transfer coefficient will be obtained by allocating the more viscous material to the shell -side, providing the flow is turbulent

1.7 STREAM FLOW -RATES:- Allocating the fluids with the lowest flow - rate to the shell -side will normally give the most economical design.

  :

SHELL AND TUBE FLUID VELOCITIES: -

High velocities will give high heat transfer coefficient but also a high pressure drop, the velocity must enough to prevent any suspend solid settling, but not so high as to cause erosion, high velocities will reduce fouling, plastic inserts are sometime used to reduce erosion at the tube inlet, typical design velocities are given below:-

 

LIQUIDS

Tube -side, process fluids: 1 to 2 m/s , maximum 4 m/ s if required to reduce fouling; water : 1.5 to 2.5 m/s.

Shell -side; 0.3 to 1 m/s.

 

VAPOURS

For vapours, the velocity used will depend on the operating pressure and density; the lower values in the ranges given below to high molecular weight materials.

VACCUM	50 to 70m/s
Atmospheric pressure	10 to 30m/s
High pressure	5 to 10 m/s

 

 

 

 

STREAM TEMPERATURES:

The closer the temperature approach used (the difference between the outlet temperature of one stream and the inlet temperature of the other stream) the larger will be the heat transfer area required for a given duty. The optimum value will depend on the application, and can only be determined by making an economic analysis of alternative designs. As a general guide the greater temperature difference should be at least 20 deg Celsius, and the least difference 5 to 7 deg Celsius for coolers using cooling water and 3 to 5 deg Celsius refrigerated brines. The maximum temperature rise in recirculated cooling water is limited to around 30 deg Celsius.

 

PRESSURE DROP:

 

In many applications the pressure drop available to drive the fluids through the exchanger will be set by the process conditions, and the available pressure drop will vary from a few millibars in vacuum service to several bars in pressure

systems.

When the designer is free to select the pressure drop an economic analysis can be made to determine the exchanger design which gives the lowest operating costs, taking into consideration both capital and pumping costs. The values suggested below can be used as general guide, and will normally give designs that are near the optimum.

LIQUIDS

Viscosity < 1 mN s/m² 35 kN/m²

1 to 10 mN s/m² 50-70 kN/m²

 

GAS AND VAPOURS

 

High vacuum 0.4-0.8 kN/m²

Medium vacuum 0.1 * absolute pressure

1 to 2 bars 0.5* system gauge pressure

Above 10 bar 0.1 * system gauge pressure

 

FLUID PHYSICAL PROPERTIES:

The fluid physical properties required for heat exchanger design are: density, viscosity, thermal conductivity and temperature enthalpy correlations (specific heats and latent heats)

 

In the correlations used to predict heat-transfer coefficients, the physical properties are usually evaluated at the mean stream temperature. This is satisfactory when the temperature changes is small, but can cause a significant error when the change in temperature is large. In these circumstances a simple method is used using formula

 

Where U₁ and U₂ are evaluated at the ends of exchanger.

 

 

 

 

 

BASIC DESIGN PROCEDURE AND THEORY

 

The general equation for heat transfer across a surface is given by:

Q=UAATM

Where,

Q=heat transferred per unit time, W

U= the overall heat transfer coefficient, W/m2

A= heat transfer area

∆Tm=the mean temperature difference

The overall coefficient is given by:

1/Uo= 1/ho + 1/hod + doln(do/di)/2kw + (do/di)(1/hid)+ (do/di)(1/hi)

Uo=Overall coefficient, W/m20

ho= outside fluid film coefficient, W/m2°C

hi= inside fluid film coefficient, W/m2°C

hod=ouside dirt coefficient(fouling factor), W/m2°C

hid=inside dirt coefficient(fouling factor), W/m2°C

kw= Thermal conductivity of the tube wall material, W/MC

di= tube inside dia, m

do= tube outside dia, m

 

The magnitude of individual coefficients will depend upon:

 

1.) Nature of heat transfer process.

2.) Physical properties of the fluids.

 3.) Fluid flow rates

4.) Physical arrangement of the heat transfer surface.

 

DESIGN PROCEDURE

1. Define the temperatures. Transfer rate, fluid flow-rates,

2. Collect together the fluid physical required: density, viscosity, thermal conductivity.

3. Decide on the type of exchanger to be used

4. Select a trial value for the overall coefficient, U

5. Calculate the mean Temperature difference, ∆Tm

6. Calculate the area required from equation

7. Decide the exchanger layout.

8. Calculate the individual coefficient.

9. Calculate the overall coefficient and compare with the trial value if the calculated value differs significantly from the estimated value, substitute the calculated for the estimated value and return to step 6.

10. Calculate the exchanger pressure drop; if unsatisfactory return to steps 7 or 4 or 3, in that order of preference

11. Optimize the design: repeat step 4 to 10, as necessary, to determine the cheapest exchanger that will satisfy the duty. usually this will be the one with the smallest area.

 

OVERALL HEAT TRANSFER COEFFICIENT

Typical values of the heat transfer coefficient is given the appendix

 

FOULING FACTORS (DIRT FACTORS)

Most process and service fluids will foul the gea transfer surfaces in an exchanger to a greater or lesser extent. The deposited material will normally have a relatively low thermal conductivity and will reduce the overall coefficient. It is therefore necessary to oversize an exchanger to allow for the reduction in performance during operation. Fouling factors are usually quoted as heat transfer resistances, rather than coefficients. They are difficult to predict and are usually based on past experience. Estimating fouling factors introduces a considerable uncertainty into exchanger design; the value assumed for the fouling factor can overwhelm the accuracy of the predicted values of the other coefficients. Fouling factors are often wrongly used as factors of safety in exchanger design.

The selection of the design fouling coefficients will often be economic decision.

 

Overall heat transfer coefficient:

1/Uo= 1/ho + 1/hod + doln(do/di)/2kw + (do/di)(1/hid)

+do/di)(1/hi)

Uo=Overall coefficient, W/m2°C

ho= outside fluid film coefficient, W/m2°C

hi= inside fluid film coefficient, W/m2°C

hod=ouside dirt coefficient(fouling factor), W/m2°C

hid=inside dirt coefficient(fouling factor), W/m2°C

kw= Thermal conductivity of the tube wall material, W/mC

di= tube inside dia, m

do= tube outside dia, m

 

MEAN TEMPERATURE (TEMPERATURE DRIVING FORCE)

Mean temperature difference can be calculated from Logarithmic mean Temperature difference or LMTD. It is only applicable to

Sensible heat transfer in true co-current or counter current flow. For

Counter-flow heat exchanger LMTD is given by:

 

∆Tlm= (T1-t2)-(T2-t1)/In((T1-t2)/(T2-t1))

∆Tlm=Log mean Temperature Difference

T1= Inlet Shell side temperature

T2= outlet Shell side temperature

t1= Inlet tube side Temperature

t2= Outlet tube side Temperature

The usual practice in the design of shell and tube exchangers is to estimate the "TRUE TEMPERATURE DIFFERENCE” from the logarithmic mean temperature difference by applying a correction factor to allow for the departure from true counters current flow:

ΔTm= FtΔTm

ATm=true Temperature difference, the mean temperature

Difference for use in design equation.

Ft= The Temperature correction factor.

 

The correction factor is a function of the shell and tube fluid temperatures and the number of tube and shell passes. It is normally correlated as function of two dimensionless temperature ratios R and S:

R=(T1-T2)/(t2-1)

S=(t2-1)/(T1-t1)

 

R is equal to the shell side fluid rate times the fluid mean specific heat; divided by the fluid rate times the tube side fluid specific heat.

S is a measure of the temperature efficiency of the exchanger. For a l shell:2 tube pass exchanger. The correction factor is shown by the Appendix 2.

 

TUBE SIDE HEAT TRANSFER COEFFICIENTAND PRESSURE DROP

HEAT TRANSFER

Turbulent flow

Heat transfer data for turbulent flow inside conduits of uniform cross-section are usually correlated by an equation of the form:

Nu - C Re^a Pr^b (µ/ µ_w)^c

Where

Nu=Nusselt No.

Re-Reynolds No.

Pr=Prandtl number

 de=Equivalent diameter

Ut=fluid velocity

u= Fluid viscosity at the bulk fluid temperature

HwFluid viscosity at the wall

Kf=fluid thermal conductivity

Gt= mass velocity, mass per unit area

 

A general equation that can be used for exchanger design is:

Nu=C Re^0.8 pr^0.33(µ / µ_w)^0.14

 

HYDRAULIC MEAN DIAMETER

In some texts the equivalent (hydraulic mean) diameter is defined differently for use in calculating the heat transfer coefficient in al conduit or channel, than for calculating the pressure drop. The perimeter through which the heat is being transferred is used in place of total wetted perimeter. In practice the use of de calculated either way will make little difference to the value of the estimated

Overall coefficient; as the film coefficient is only, roughly, proportional to de02 .it is full wetted perimeter that determines the flow regime and the velocity gradients in a channel.

 

LAMINAR FLOW

Below a Reynolds number of about 2000 the flow in pipes will be laminar. Providing the natural convection effects are small, which will normally be so in forced convection, the following equation can be used to estimate the film heat-transfer coefficient:

Nu= 1.86(Re Pr) 0.93 (do/L)0.33 (w/w)...4

Where L is the length of the tube in meters.

HEAT-TRANSFER FACTOR. Jh:

It is often convenient to correlate heat transfer data in terms of heat transfer "" factor, it is similar to the friction factor used for pressure drop. The heat transfer factor is defined as:

Jh = St Pr^0.67 (µ / µ_w)^-0.14

The use of jh factor enables data for laminar and turbulent flow to be represented on the same graph. The jh values obtained from this graph can be used with the above mentioned equation to estimate

The heat transfer coefficients for heat exchanger tubes and commercial pipes. The coefficient estimated for pipes will normally be conservative as pipes are rougher than the tubes used for heat exchangers, which are finished to closer tolerances. The relationship between jh and jH is given by:

jH=jh (Re)

Where jH is another heat transfer factor defined by Kern and other workers.

 

COEFFICIENT FOR WATER:

The equation below has been adapted from data given by Eagle and Ferguson:

h_i = (4200 (1.35 +0.02t) ut^0.8)/di ^0.2

Where hi = inside coefficient for water.

t = water temperature.

u;= water velocity

di = tube inside diameter

 

TUBE-SIDE PRESSURE DROP:

There are two major sources of pressure loss on the tube-side of a shell and tube exchanger: the friction loss in the tube side is due to sudden contraction and expansion and flow reversals that the fluid experiences in flow through the tube arrangement. The tube friction loss can be calculated using the basic equation for isothermal flow

∆P = 8jf (L'/di) pu_t²/2.

Where jf is the dimensionless friction factor and L' is the effective pipe length

The flow in heat exchanger will clearly not be iso-thermal, and this is allowed for by including an empirical correction factor to account for the change in physical properties with temperature, Normally the change in viscosity is considered.

∆P = 8jf (L'/di) pu_t²/2. (µ/µ_w)^-m

m = 0.25 for laminar flow

    = 0.14 for turbulent flow.

Final equation for the calculation of pressure drop in tube is given as follows:

∆Pt = Np[8jf (L/di) (u/µw)+2.5) pu_t² /2

Where,

∆Pt= tube side pressure drop

Np=no. of tube passes

Ut= tube side velocity

L= length of tube

 

SHELL SIDE HEAT TRANSFER AND PRESSURE DROP

The complex flow pattern on shell side and great no. of variables involved make it difficult to predict the shell side coefficient and pressure drop with complete assurance. Therefore KERN METHOD was used for the calculation of heat transfer coefficient and pressure drop.

PROCEDURE

1. Calculate the area for cross-flow As for the hypothetical row

Of tubes at the shell equator, given by:

As = (pt-do) Ds 18 pt

Where, pt = tube pitch,

do = tube outside diameter,

Ds = shell inside diameter, m,

1_B = baffle spacing,m.

 

The term (pt-do)/pt is the ratio of the clearance between tubes and the total distance between tube centres.

2. Calculate the shell side mass velocity Gs and the linearvelocity u_s :

Gs = Ws/As

us = Gs/p

Where, Ws = fluid flow rate on the shell side, kg/s,

p=shell side fluid density, kg/m

3. Calculate the shell-side equivalent diameter (hydraulic diameter), for an square pitch

de=4((pt?-IIdo?)/4), IIdo

= 1.27(pt2-IIdo?)/do

for an equilateral triangular pitch arrangement:

de = 4(pt/2*0.87pt-1/2 II do? [4)/(IIdo/2)

= 1.10(pt2-0.917do?)/do

Where de = equivalent diameter, m.

4. Calculate the shell-side Reynolds number, given by:

Re = Gs de/u

= Us de p/h

5. For the calculated Reynolds number, read the value of jh from Appendix 3 for the selected baffle cut and tube arrangement, and calculate the shell-side heat transfer coefficient hs from:

Nu = hs de/kf

=jh Re Pr!3 (w/w) 0.14

the tube wall temperature can be estimated using the method given for tube side section.

6. For the calculated shell-side Reynolds number, read the friction factor from Appendix 4 and calculate the shell-side pressure drop from:

∆Ps = 8 jf (Ds/de) (L/13) pu_s²/2 (u/u_w).^-0.14

Where, L = tube length,

l_B = baffle spacing.

The term (L/1B) is the number of times the flow crosses the tube bundle = (Nb+1), where Nb is the no of baffles.

 

 

Conclusion

 Khasa distillery is following all the guidelines set by ppcb (Punjab pollution control board).

It is an eco-friendly distillery causing No pollution problem.

The sludge collected from the sludge pits is pits in organic & inorganic nutrients which are used as manure by the farmers. Even this distillery producing its own electricity with the help of methane gas Supply by gas holding plant so it does not depend on Punjab electricity board and reduce the burden of P.S.E.B

 

REFERENCES

 

1.   Khasa distillery PVT Ltd, Manuals on Fermentation, Distillation

2.   http://www.energymanagertraining.com/distillery/Manufacture_of_alcohol%20.htm accessed on 7,Oct

3.   http://dwb4.unl.edu/Chem/CHEM869P/CHEM869PLinks/www-dept.usm.edu/~bsclabs/380/yeasts.htm  accessed on 27,July

4.   http://www.distillery-yeast.com/ARTISANDISTILLING1.0.0.pdf accessed on 6,Oct

5.   http://www.distillery-yeast.com/instruments.htm  accessed on 6,Oct

6.   http://www.andrew.cmu.edu/user/jitkangl/Fermentation%20of%20Ethanol/Fermentation%20of%20Ethanol.htm accessed on 7,Oct

7.   http://www.h2flow.com/Website2003/Products/eimco/Effluent_Clarifier.pdf  accessed on 29,Aug

8.   Principles of Fermentation Technology, Whittaker, Page no.  109-110;299-300;186-187.