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A LIST OF BASIC SAFETY RULES
1.When you handle chemicals wear eye protection (chemical splash goggles or full
Face shield).
2. When you work with furnaces for heat treatment procedures or other thermally
activated equipment you should use special gloves to protect your hands.
3. Students should wear durable clothing that covers the arms, legs, torso and feet.
4. To protect clothing from chemical damage or other dirt, wear a lab apron or lab coat. Long
hair should be tied back to keep it from coming into contact with lab chemicals Or flames.
5. In case of injury (cut, burn, fire etc.) notify the instructor immediately.
6. In case of a fire or imminently dangerous situation, notify everyone who may be
affected immediately; be sure the lab instructor is also notified.
7. If chemicals splash into someone's eyes act quickly and get them into the eye wash station,
do not wait for the instructor.
8. In case of a serious cut, stop blood flow using direct pressure using a clean towel, notify the
lab instructor immediately.
9. Eating, drinking and smoking are prohibited in the laboratory at all times.
10. Never work in the laboratory without proper supervision by an instructor.
11. Never carry out unauthorized experiments. Come to the laboratory prepared. If you are
unsure about what to do, please ask the instructor.
LABORATORY CLASSES - INSTRUCTIONS TO STUDENTS
1. Students must attend the lab classes with ID cards and in the prescribed uniform.
2. Boys-shirts tucked in and wearing closed leather shoes. Girls’ students with cut shoes,
overcoat, and plait incite the coat. Girls’ students should not wear loose garments.
3. Students must check if the components, instruments and machinery are in working
condition before setting up the experiment.
4. Power supply to the experimental set up/ equipment/ machine must be switched on
only after the faculty checks and gives approval for doing the experiment. Students only
after the faculty checks and gives approval for doing the experiment. Students getting
permissions from the faculty.
5. Any damage to any of the equipment/instrument/machine caused due to
carelessness, the cost will be fully recovered from the individual (or) group of
students.
6. Students may contact the lab in charge immediately for any unexpected incidents and
emergency.
7. The apparatus used for the experiments must be cleaned and returned to the
technicians, safely without any damage.
8. Make sure, while leaving the lab after the stipulated time, that all the power
connections are switched off.
9.EVALUATIONS:
All students should go through the lab manual for the experiment to be carried out for that day and come fully prepared to complete the experiment within the prescribed periods. Student should complete the lab record work within the prescribed periods.
Students must be fully aware of the core competencies to be gained by doing experiment/exercise/programs.
Students should complete the lab record work within the prescribed periods.
The following aspects will be assessed during every exercise, in every lab class and marks will be awarded accordingly:
Preparedness, conducting experiment, observation, calculation, results, record presentation, basic understanding and answering for viva questions.
In case of repetition/redo, 25% of marks to be reduced for the respective component.
NOTE 1:
Preparation means coming to the lab classes with neatly drawn circuit diagram/experimental setup /written programs /flowchart, tabular columns, formula, modelgraphs etc in the observation notebook and must know the step by step procedureto conduct the experiment.
Conducting experiment means making connection, preparing the experimentalsetup without any mistakes at the time of reporting to the faculty.
Observation means taking correct readings in the proper order and tabulating thereadings in the tabular columns.
Calculation means calculating the required parameters using the approximateformula and readings.
Result means correct value of the required parameters and getting the correctshape of the characteristics at the time of reporting of the faculty.
Viva voice means answering all the questions given in the manual pertaining to theexperiments.
Full marks will be awarded if the students performs well in each case of theabove component
CONTENT
Sl.No.
Date Name of the Experiment Page MarksStaff
Initials
1. Pensky Martens Apparatus
2. Distillation Characteristics
3. API Gravity
4. Softening Point
5. Aniline Point
6. Cloud point and Pour point
7. Copper strip corrosion
8. Bomb Calorimeter
9. KFR Titration
10. Centrifuge
11. Dean and Stark Apparatus
12.Determination of Kinematic viscosity
13. Cleveland open cup apparatus
1. FLASH POINT AND FIRE POINT
BY PENSKY MARTENS APPARATUS
AIM
To determine the flash point and fire point of fuel oils by using Pensky Martens apparatus (closed type).
DEFINITION
FLASH POINTThe lowest temperature of the sample, corrected to a barometric pressure of 101.3 kPa 760 mm Hg , at which application of a test flame causes the vapour of the sample to ignite under specified conditions of test.
FIRE POINTThe fire point, is defined as the temperature at which the vapour continues to burn after being ignited.
SUMMARY OF METHOD
The sample is heated at a slow, constant rate with continual stirring. A small flame is directed into the cup at regular intervals with simultaneous interruption of stirring. The flash point is the lowest temperature at which application of the test flame causes the vapour above the sample to ignite.
SIGNIFICANCE
Flash point measures the response of the sample to heat and flame under controlled laboratory conditions.
It is only one of a number of properties which must be considered in assessing the overall flammability hazard of a material.
Flash point is used in shipping and safety regulations to define ‘flammable’ and ‘combustible’ materials.
APPARATUS
Pensky Martens Closed Tester
Thermometers (Two standard thermometers shall be used with the Pensky-Martens tester)
TABULATION
S.No. SAMPLES FLASH POINT (ºC) FIRE POINT(ºC)
PREPARATION OF SAMPLE
Samples of asphalts or very viscous materials may be warmed until they are reasonable fluid before they are tested. However, no sample should be heated more than is absolutely necessary. It shall never be heated above a temperature of 17°C ( 30°F ) below its expected flash point.
APPARATUS SPECIFICATIONS
A typical assembly of the apparatus, gas heated, is shown in Fig. The apparatus shall consist of a test cup, cover, and stove conforming to the following requirements.
Cup - The cup shall be of brass, or other non-rusting metal of equivalent heat conductivity, and shall conform to the dimensional requirements
Cover Proper - The cover shall be brass, and shall have a rim projecting downward almost to the flange of the cup. The rim shall fit the outside of the cup with a clearance not exceeding 0.36 mm 0.014 in on the diameter.
Shutter - The cover shall be equipped with a brass shutter approximately 2.4 mm ( 3/32 in ) thick operating on the plane of the upper surface of the cover. cover openings shall be exactly open and the tip of the exposure tube shall be fully depressed.
Flame Exposure Device - The flame-exposure device shall have a tip with an opening 0.69 to 0.79 mm (0.027 to 0.031 in) in diameter. This tip shall be made preferably of stainless steel, although it may be fabricated of other suitable metals
Pilot Flame - A pilot flame shall be provided for automatic relighting of the exposure flame. Stirring Device - The cover shall be equipped with a stirring device mounted in the centre of the cover and carrying two 2-bladed metal propellers.
Stove Heat shall be supplied to the cup by means of a properly designed stove which is equivalent to an air bath. The stove shall consist of an air-bath and a top plate on which the flange of the cup rests.
Air Bath The air bath shall have a cylindrical interior and shall conform to the dimensional requirements in Fig.
Top PlateThe top plate shall be of metal, and shall be mounted with an air gap between it and the air bath.
PROCEDURE
The oil cup was cleaned using solvent. The cup was filled with fresh sample up to the mark. The cup was placed in the apparatus bath. The lid is placed on the cup and the thermometer was also inserted. The electrical heater was turned to 50% of input volts and oil is heated. After that spring handle was rotated at every degree rise from this point. The temperature was noted at which the flash occurs. The fire point was noted at which the fuel burnt continuously for 5 seconds. The experiment was repeated for different samples.
RESULTFlash point and fire point of given samples are ________________ is _______ oC
2. DISTILLATION CHARACTERISTICS
SCOPE
To determine the distillation characteristics (boiling range) of the given sample using the distillation apparatus.
DISTILLATION This method of test covers the distillation of motor gasoline, aviation gasoline, aviation
turbine fuels, special boiling point spirits, naphtha, white spirit, kerosene, gas oils, distillate fuel oils and similar petroleum products. A 100 ml sample is distilled under prescribed conditions which are appropriate to its nature. Systematic observations of thermometer readings and volumes of condensate are made, and from the data, the results of the test are calculated and reported.
The distillation (volatility) characteristics of hydrocarbons have an important effect on their safety and performance, especially in the case of fuels and solvents. The boiling range gives information on the composition, the properties, and the behavior of the fuel during storage and use. Volatility is the major determinant of the tendency of a hydrocarbon mixture to produce potentially explosive vapors.
The distillation characteristics are critically important for both automotive and aviation gasoline, affecting starting, warm-up, and tendency to vapor lock at high operating temperature or at high altitude, or both. The presence of high boiling point components in these and other fuels can significantly affect the degree of formation of solid combustion deposits.
Distillation limits are often included in petroleum product specifications, in commercial contract agreements, process refinery/control applications, and for compliance to regulatory rules.
This test method can be applied to contaminated products or hydrocarbon mixtures. This is valuable for fast product quality screening, refining process monitoring, fuel adulteration control, or other purposes including use as a portable apparatus for field testing.
SIGNIFICANCE
Distillation (volatility) characteristics of petroleum products are indicative of performance in their intended applications.
Petroleum product specifications generally include distillation limits to ensure products of suitable volatility performance.
The empirical results obtained by use of this distillation method have been found to correlate with automotive equipment performance factors and with other characteristics of petroleum products related to volatility.
For motor spirit the 10% distillation value gives an indication of the engine start conditions, also the final boiling point.
OBSERVATION
S.No Volume of Distillate collected (ml)
Temperature ºC
TERMINOLOGY
Initial Boiling PointThe thermometer reading which is observed at the instant that the first drop of condensate falls from the lower end of the condenser tube,
End-Point or Final Boiling PointThe maximum thermometer reading obtained during the test. This usually occurs after the evaporation of all liquid from the bottom of the flask. The term ‘maximum temperature’ is a frequently used synonym.
Dry Point
The thermometer reading observed at the instant the last drop of liquid evaporates from the lowest point in the flask. Any drops or film of liquid on the side of the flask or on the thermometer are disregarded.
Decomposition Point
The thermometer reading which coincides with the first indication of thermal decomposition of the liquid in the flask.
Percent Recovered
The volume in ml of condensate observed in the receiving graduate, in connection with a simultaneous thermometer reading.
Percent Recovery
The maximum percent that is recovered.
Percent Total Recovery
The combined percent recovery and residue in the flask.
Percent Loss
100 minus the percent total recovery.
Percent Residue
The percent total recovery minus the percent recovery, or the volume of residue in milliliters if measured directly.
Percent Evaporated
The sum of the percent recovered and the percent loss.
PROCEDURE
The given flask is to be thoroughly cleaned using solvent and dried.
The given test sample is then taken inside the flask and the cork with appropriate thermometer is placed on the neck of the flask.
The flask is placed on the asbestos board and fixed to the metal condensers with a cork. The asbestos board is raised of lowered till the flask is properly supported.
The 100cc measuring cylinder is placed below the condenser outlet. The heater is then switched on and the temperature variation is noted.
The temperature at which the first drop of distillate is collected in the measuring cylinder is noted and reported as the initial boiling point.
Heat is controlled, so that the distillation process is at a uniform state.
Middle boiling point is the temperature at which 50% of oil distills off.
RESULT
The Distillation characteristics are studied for the given samples and the values are noted as follows:
1. Initial boiling point = º C
2. Middle boiling point = º C
3. Percentage of recovery =
4. Percentage of non-volatile residue =
5. Final boiling point = º C
API GRAVITY - DIAGRAM
3. DETERMINATION OF API GRAVITY OF CRUDE PETROLEUM AND LIQUID PETROLEUM PRODUCTS BY HYDROMETER METHOD AND SPECIFIC GRAVITY BOTTLE METHOD
AIM
To determine the API gravity of crude petroleum and liquid petroleum products by hydrometer method and specific gravity bottle method.
THEORY
This method covers the laboratory determination, using a glass hydrometer, of the density, relative density, or API gravity of crude petroleum, petroleum products, or mixtures of petroleum and non-petroleum products normally handled as liquids and having a Reid vapour pressure of 1.8 bar (179 KPa) or less. The values are measured on a hydrometer at convenient temperatures, readings of density being reduced to 15 oC, and that of specific gravity and API gravity to 15.6 oC, by means of international standard tables.
CLASSIFICATIONS OR GRADES
Crude oil is classified as light, medium or heavy, according to its measured API gravity.
Light crude oil is defined as having API gravity higher than 31.1 °API. Medium oil is defined as having API gravity between 22.3 °API and 31.1 °API. Heavy oil is defined as having API gravity below 22.3 °API.
SIGNIFICANCE
Accurate determination of density, relative density, or API gravity of petroleum and its products is necessary for the conversion of measured volumes to volumes at standard temperature of 15°C.
FORMULA
API Gravity
A special function of specific gravity at 15.6/15.6 oC is represented by:
API gravity, degrees = [141.5 /Specific gravity at 15.6/15.6 oC] - 131.5
APPARATUS REQUIRED
Hydrometer Hydrometer cylinders Specific gravity bottle
OBSERVATIONS
Sl.No SAMPLES
SPECIFIC GRAVITY
At room temperature using Hydrometer
At room temperature using Specific gravity bottle method
SPECIFIC GRAVITY BOTTLE METHOD
Weight of the empty specific gravity bottle =
Weight of the specific gravity bottle with sample 1 =
Weight of the specific gravity bottle with sample 2 =
Weight of the specific gravity bottle with sample 3 =
Weight of the specific gravity bottle with sample 4 =
PROCEDURE
Hydrometer method
The samples were transferred to hydrometer cylinders without any splashing to avoid air bubbles.
The cylinders containing samples were placed in vertical position in a location free from air currents.
The hydrometer was gently lowered into the sample in cylinders such that the hydrometer should not touch the walls of the cylinder.
The hydrometer was allowed to float and when it comes to rest, the specific gravity indicated by the hydrometer for different samples at room temperature were noted.
From the specific gravity values the API gravity for the given samples were calculated.
Specific gravity bottle method
The samples were taken in each specific gravity bottle. The specific gravity bottle with the samples and the weight of the empty specific
gravity bottle were measured. The readings were tabulated and the specific gravity for different samples was
calculated. From the specific gravity values the API gravity for the given samples were calculated.
RESULT
The API gravity of the given samples using hydrometer and specific gravity bottles were calculated and tabulated as follows
Sl.No. Samples
API gravity
Hydrometer method Specific gravity bottle method
4. SOFTENING POINT
AIM
To determine the softening point of the given sample bitumen using ball and ring apparatus.
APPARATUS REQUIRED
Ring and ball apparatus Steel balls Brass rings Thermometer Stirrer Water bath
SIGNIFICANCE
To find the consistency of bitumen It is regarded by same indication of viscosity It is used in the designation of hard as oxidized bitumen.
THEORY
The temperature at which the substance attains a particular degree of softness under specified condition of test is called softening point.
Bitumen is specified by softening point. Bitumen being amorphous does not melt sharply but gradually becomes softer and less viscous as the temperature rises.
For this reason, the determination of the softening point must be made by fixed arbitrary and closely defined method.
The softening point of bitumen is rounded out by the ball and ring test.
APPLICATION
Used in annealing of bitumen. Processing of plastics. Determining the quality of bitumen.
PROCEDURE
A beaker is taken and filled with ¾ of it with water. The sample is placed in the ring and the steel ball is kept over the sample at the
middle of the ring. The whole ring and ball is immersed into the beaker which is filled with water.
The water in the beaker is heated by electrical coil. A thermometer is inserted to note the temperature. As the temperature increase, the sample gets softens and the steel ball over the sample
gets immersed and finally drops out. The temperature at which the ball falls down from the ring is noted as softening point
of the sample. The ring is washed and replaced with another sample and the process is repeated.
RESULT
The softening point of given first sample = The softening point of given second sample =
5. ANILINE POINT
AIM
To determine the aniline point of the given sample.
APPARATUS
The tube approximately 25mm in diameter and 150mm in length made of heat-resistant glass.
A Jacket-approximately 37 to 42mm in diameter and 175mm in length made of heat-resistant glass.
A Stirrer-manually operated, approximately 2mm in diameter soft iron wire.
THEORY
Aniline point
Aniline is a poor solvent for aliphatic hydrocarbons and excellent one for aromatics. This property is used in the aniline point test. Aniline point of oil is the lowest temperature at which the oil is completely miscible with an equal volume of aniline.
Equal volumes of the sample and aniline (5 ml each) are heated or cooled with stirring in a jacketed test tube and temperature at which complete miscibility occurs is noted.
High aniline point indicates that the fuel is highly paraffinic and hence has a high diesel index and very good ignition quality. In case of aromatics the aniline point is low and the ignition quality is poor
Diesel index
Diesel index is an indication of the ignition quality of a diesel fuel. This is determined by calculation from the specific gravity and the aniline point of the sample. Although it is of the same order as the cetane number, it may differ widely from the cetane number. Higher the diesel index better is the ignition quality of the diesel fuel. It is normally used as a guide to ignition quality of the diesel fuel in the absence of test engine for the direct measurement of cetane number.
The diesel index is calculated as follows:
(a) Diesel index = (Aniline point,ºF ׺API)/100(b) Diesel index = (Aniline gravity constant)/100(c) Diesel index = (Cetane number −10)/0.72
Cetane number
Cetane number is related to the ignition delay of a fuel in a diesel engine, i.e. how rapidly combustion begins after injection of the fuel into the combustion chamber.
The shorter the ignition delay period, higher is the cetane number of the fuel
Cetane number is the index of the ignition quality of a fuel. High cetane number fuels will facilitate easy starting of compression ignition engines, particularly in cold weathers, and faster warm up. These also result in increased engine efficiency and power output, reduced exhaust smoke and odour and combustion noise. In the absence of test engine, the diesel index or the calculated cetane index will give an approximate idea of the ignition quality of the fuel.
Cetane number= 0.72×Diesel index + 10
PROCEDURE
The apparatus was dried and cleaned.
10ml of aniline and 10ml of the sample were dried and pipetted into the test tube fitted with stirrer and thermometer.
The thermometer in the test tube was centered to make the immersion mark at the liquid level; it is assured that the thermometer bulb does not touch the side of the tube.
In the case of not mixing of aniline-sample at normal temperature, heat is applied directly to the jacket tube so that the temperature raised at a rate of 1-3ºC/min till complete miscibility was obtained.
Stirring is continued and the mixture is allowed to cool at a rate of 0.5 to 1ºC/min.
Cooling is continued to a temperature of 1 to 2ºC below the first appearance of turbidity.
The temperature at which the mixture suddenly became cloudy throughout is recorded as the aniline point.
RESULT
Results for the aniline point experiment were found to be
Aniline point =
Diesel index =
Cetane number =
6. CLOUD AND POUR POINT DETERMINATION
AIM
To determine the Cloud point and pour point of the given sample.
REQUIREMENTS
Cloud and pour point apparatus, Thermometer, Ice crystals.
DEFINITIONS
The cloud point of a fluid is the temperature at which dissolved solids are no longer completely soluble, precipitating as a second phase giving the fluid a cloudy appearance. This term is relevant to several applications with different consequences.
Also, the pour point can be defined as the lowest temperature expressed in multiples of 3ºC at which the oil is observed to flow when cooled and examined under prescribed conditions.
THEORY
Cloud point and pour point are indicators of the lowest temperature of utility for petroleum products. Cloud Point gives a rough idea of temperature above which the oil can be safely handled without any fear of congealing or filter clogging. The sample is periodically examined while it is being cooled in the cloud and pour point apparatus. The highest temperature at which haziness is observed (cloud point), or the lowest temperature at which the oil ceased to flow is observed (pour point), is reported as the test result.
The cold filter plugging point test is used to determine the extent to which diesel fuel or gas oil will flow, even though the temperature is below that at which wax crystals normally appear, i.e. cloud point.
Pour point is a well established test to estimate the temperature at which a sample of oil becomes sufficiently solid to prevent its movement by pumping. The pour point indicates the waxy nature of the oils.
SAMPLES SHOWING CLOUD AND POUR POINT
CLOUD AND POUR POINT EXPERIMENTAL SETUP
CLOUD AND POUR POINT EXPERIMENTAL SETUP
PROCEDURE
Measuring cloud point of petroleum product:
The test oil is required to be transparent in layers 40mm in thickness (in accordance with ASTM D2500). The crystals of the sample typically first form at the lower circumferential wall with the appearance of a whitish or milky cloud. The cloud point is the temperature at which these crystals first appear.
1. The test sample is first poured into a test jar to a level approximately half full.2. A cork carrying the test thermometer is used to close the jar. 3. The thermometer bulb is positioned to rest at the bottom of the jar. 4. The entire test subject is then placed in a constant temperature cooling bath on top of
a gasket to prevent excessive cooling.
5. At every 1°C, the sample is taken out and inspected for cloud then quickly replaced. 6. Successively lower temperature cooling baths may be used depending on the cloud
point. 7. Lower temperature cooling bath must have temperature stability not less than 1.5 K
for this test.
Measuring pour point of petroleum product:
Two pour points can be derived which can give an approximate temperature window depending on its thermal history. Within this temperature range, the sample may appear liquid or solid. This peculiarity happens because sample crystals form more readily when it has been heated within the past 24hrs and contributes to the lower pour point.
The upper pour point is measured by pouring the test sample directly into a test jar. The sample is then cooled and then inspected for pour point as per the usual pour point method.
The lower pour point is measured by first pouring the sample into a stainless steel pressure vessel. The vessel is then screwed tight and heated to above 100oC in an oil bath. After a specified time, the vessel is removed and cooled for a short while. The sample is then poured into a test jar and immediately closed with a cork carrying the thermometer. The sample is then cooled and then inspected for pour point as per the usual pour point method
RESULT
The pour point of the given sample was found to be ---------0C.
The cloud point of the given sample was found to be ---------0C
7. COPPER STRIP CORROSION TEST
AIM
To detect the corrosiveness of the given sample using copper strip corrosion test.
PRINCIPLE
The method covers the detection of corrosiveness to copper of aviation gasoline from tractor fuel, solvent, kerosene, diesel, fuel oil, lube oil, certain other petroleum products.
A polished copper strip is immersed in a given quantity of sample and heated at a temperature and for a time characteristics of the material being tested. At the end of this period, the copper strip is removed, washed and compared with copper strip corrosion standards. It is particularly important that all types of feed sample which should pass a tarnished strip classification. We collected clean glass bottles, plastic bottles or other suitable containers that will not affect the corrosiveness properties of the sample.
REQUIREMENTS
Copper strip corrosion test bomb Constant temperature water bath Polishing ice Glass test tube Polishing paper
SIGNIFICANCE AND USE
This test method is suitable for setting specifications, for use as an internal quality control tool, and for use in development or research work on industrial aromatic hydrocarbons and related materials. It also gives an indication of the presence of certain corrosive substances which may corrode equipment, such as acidic compounds or sulfur compounds.
PROCEDURE
The test is to be operated at 50oC constant temperature. The bath is set at the desired working temperature and waits for 20 minutes of
time after the start. The copper strip is prepared for performing test. It is washed properly with
solvent (acetone) and surface of strip is prepared by rubbing with silicon carbide grid paper.
Clamp the strip with ice and polish it until uniform rubbing, when strip is clean immerse it in prepared sample.
The strip is kept into 30 ml of sample which is kept inside the test bomb and the lid is screwed tight.
After two hours in the bath the bomb is withdrawn and it is cooled with water. The bomb is opened, the test tube is taken out and carefully the strip is
withdrawn from the sample. The strip is compared with ASTM corrosion standards comparison chart and
report the tarnish level.
RESULT
The corrosiveness of the given sample is found out using the copper strip and comparing it with ASTM standards and its value is found to be ---------------------------
8. BOMB CALORIMETER
AIM:
To determine the calorific value of a given fuel
INTRODUCTION:
The heating value or calorific value of a substance, usually a fuel or food, is the amount of heat released during the combustion of a specified amount of it. The calorific value is a characteristic for each substance. It is measured in units of energy per unit of the substance, usually mass, such as: kcal/kg, kJ/kg, J/mol, Btu/m³. Heating value is commonly determined by use of a bomb calorimeter.
The bomb calorimeter is the most common device for measuring the heat of combustion or calorific value of a material. With this apparatus a test specimen of specified mass is burned under standardized conditions. The heat of combustion determined under these conditions is calculated on the basis of the observed temperature rise while taking account of heat loss. The combustion process is initiated inside an atmosphere of oxygen in a constant volume container, the bomb, which is a vessel built to withstand high pressures. It is immersed in a stirred water bath, and the whole device is the calorimeter vessel. The calorimeter vessel is also immersed in an outer water bath. The water temperature in the calorimeter vessel and that of the outer bath are both monitored
THEORY:
The calorific value of a fuel is the amount of energy liberated by burning completely unit quantity of fuel. A small amount is burned under high pressure oxygen. The calorific value calculated by measured the energy liberated.
Heat liberated = Heat gained by water and calorimeter
mf *CV = (mw + mc) (T2-T1)*(Cp)
where
mf : mass of the fuel.
mw : mass of water in calorimeter.
mc : mass of water equivalent of the calorimeter which should be determined using a fuel of know calorific value.
T2-T1: temperature rise.
Cp: specific heat of water.
PROCEDURE:
1. A small quantity of fuel (about 1 gram) is weighted.
2. The ignition wire is fixed and the bomb is closed.
3. The bomb is charged with oxygen to a pressure of about 30 bars.
4. The bomb is inserted in the calorimeter and about 2 Kg of water is poured.
5. The Beckman thermometer is inserted and the stirrer is started.
6. Temperature of water is recorded every 10 seconds.
EXPERIMENTAL SETUP:
Figure shows the experiment setup: bomb calorimeter and Beckman thermometer.
An adiabatic bomb calorimeter has the metal bomb inside of a metal bucket containing water. That metal bucket sits loosely inside an insulated jacket. There is a stirrer that sticks into the water in the bucket and is driven by a motor outside of the calorimeter. A thermometer also sticks into the water in the bucket and is the device that will be used to determine the change in temperature during the reaction. Two electrical leads connect to the top of the bomb from outside and they will deliver the current that initiates the reaction.
The metal bomb provides a constant-volume system in which the combustion will reaction take place. The sample pellet is placed in the ignition cup and the fuse wire is carefully arranged to touch the pellet but not the cup. The bomb is sealed by screwing the cap on and then filled with a high pressure of pure oxygen. The electrical connections are made at the top and the bomb is placed into the water bucket. Figure 2 shows a sketch of the bomb calorimeter cross section.
Figure 2 a sketch of the bomb calorimeter cross section
Data observed
Table 1:
Change of temperature with time
Time
[ s ]
Temperature
[ o C ]
Time
[ s ]
Temperature
[ o C ]
0 250
10 260
20 270
30 280
40 290
50 300
60 310
70 320
80 330
90 340
100 350
110 360
120 370
130 380
140 390
150 400
160 410
170 420
180 430
190 440
200 450
210 460
220 470
230 480
240
Pressure in the bomb=30 bar
Mass of water = 2 Kg
Mass of fuel = 1 g
Specific heat capacity cp =4186 J/Kg K
Sample calculation:
Heat liberated from fuel = Heat gained by water and calorimeter
mf * C.V = ( mw + mc ) ( T2 – T1 ) (cp )
C.V = [ J / Kg ]
Results and discussion
The calorific value of the given sample in this experiment is found to be ------------
9. KFR TITRATIONAIM:
To determine the water content in the given petroleum sample.
APPARATUS REQUIRED:
Base unit consists of rear panel and front panel. Front panel has stirrer on switch.Stirrer speed regulator 3 LED and MVP set potentiometerGreen LED O- equipment onYellow LED P- nearing end point indicationRed LED E. - endpoint indicationRear panel has main ON switch. Plug socket, fuse 500 mA and electrode terminals e.Magnetic stirrer:Stirrer on - off switch is located on the front panel. Use regulator to set the required speed. After setting required speed, use on off switch only for operating the stirrer. Avoid using the regulator frequently.
SETTING UP THE EQUIPMENT FOR OPERATION:
Fix stand rod to the base unit and mount the burette assembly on the instrument. The burette assembly will freely slide up and down and revolve around the standard
Reaction assembly.Pressure filling auto zero setting burette assembly.
KFR bottle can be screwed on the plastic cap. Operate bellow holding vertically and closing the T joint connection tube. Air pressure in the KFR bottle increases and lifts KFR to fill the burette. When the level crosses o mark remove the finger zero level sets automatically. Reaction vessel can be filled or removed by lifting the burette assembly.
Reaction vessel is connected to the electrode terminals on rear panel through pair of connecting jack wires.
Using methanol bottle instead of KFR bottle can wash the burette assembly. If you want to adjust the zero level, adjust the Teflon tip I.e. just pull out or insert the
Teflon tip and set to zero.
PROCEDURE:
1. Neutralization of KFR.2. Place magnetic stirring paddle into reactor carefully, using the forceps. 3. Never drop the Teflon magnetic paddle into the reactor after mounting on the
magnetic stirrer.4. The paddle will be pulled down with great force and damage the reaction flask.5. Pour about 20 ml grade methanol into the reactor.6. Fill the burette with KFR.7. Connect jack wire to the reactor and electrode terminals marked e.8. Lift the burette assembly by 50 cm and place the reactor on the magnetic stirrer lower
the burette assembly and allow it to rest on the reactor.9. Switch on the equipment power on o green LED will glow.10. Switch on the stirrer.11. Set required speed for vigorous stirring with minimum spurting and wait for10 to 15
seconds for uniform stirring.12. Add KFR reagent by drops into the burette valve.13. Add KFR reagent until pre end point p yellow LED glows, this will indicate nearing
end point.14. Now add KFR by drops slowly giving 10-20 seconds between additions until E red
LED glows continuously for 30 seconds.15. At the end point of the titration P yellow LED will go off and E red LED will glow
continuously at the point wait and watch for 30 seconds indicating current flow is steady and continuous.
STANDARDIZATION OF KFR:
1. For finding out the factor of water equivalent.2. Fill the burette3. Weigh 1 ml of distiller water using electronic balance in a syringe.4. Close the reaction vessel with stopper .start magnetic stirrer and allow the contents to dissolve for some time.
5. Distilled water dissolves immediately.6. Fill the burette and titrate up to the end point as described in neutralization.7. After completion of cycle, note the burette reading.
F factor of equivalent = M/AM is the weight of the waterA is the volume of KFR
ESTIMATION OF WATER CONTENT IN UNKNOWN SAMPLE:Viscous liquids can be weighed and dropped into the reactor using droppers, light liquids can be measured and added into the reactor using pipettes or syringe.
Percentage of water content = B *F ______ V*D* 10B is the volume of KFRF is the factor of water equivalentV is the volume of the sampleD is the density of the sample.
TABULATION:
Neutralization of KFR
Burette reading (KFR volume) =
Standardization of KFRWeight of water M =Volume of KFR A =
Factor of water equivalent F= M ------ A
Estimation of water content in the unknown sample
Volume of KFR =Volume of sample =Density = 1 mg/ml
Percentage of water content = B*F = ----- V*D*10
RESULT:
The percentage of water present in the given petroleum sample is -----------.
10. DETERMINATIONOF WATER AND SEDIMENTS BY CENTRIFUGE METHOD
AIM:
To determine the amount of the sediments present in the given sample
APPARATUS REQUIRED
Centrifuge, Centrifuge tubes (8inch), Bath, Toluene, Demulsifier solution (phenol or Naphthenic acid)
THEORY
Centrifugal forces enhance the dissipation of colloidal particles from colloidal solution, an equal volume of crude and water saturated xylene were placed into a cone shaped centrifuge. After Centrifugation, the higher gravity water and sediments separates at the bottom of the tube. The water and sediment content of the crude oil are important because they can cause corrosion of the equipment and problems in processing. It is important to measure accurately the net volumes of actual oil in sales taxation exchanges and custody transfers.
PROCEDURE
1. Fill two centrifuge tubes to the 50 millilitre (ml) or 100 part mark with the homogeneous sample to be tested. Read the top of the meniscus (the curved upper surface of a liquid column).
2. Fill the two tubes with 50 ml of solvent which brings the total contents of the tubes to the 100 ml or the200 parts mark. The acceptable solvents are Stoddard, kerosene, toluene, and xylene. Note that toluene and xylene should be water-saturated at test temperature.
3. Invert the tubes 10 times to mix the sample and solvent. This should be done below eye level for safety, and safety glasses are highly recommended. Solvents can be hazardous and should be handled with caution. Material Safety Data Sheets (MSDS) and handling precautions recommended by the chemical manufacturer should be followed.
4. Place the tubes in the preheater and heat to 140º F +/- 5º F.
5. Invert the tubes ten times again to mix.
6. Place the tubes on opposite sides of the centrifuge to balance the load. Close the centrifuge lid.
7. Centrifuge for a minimum of 5 minutes.
8. When the centrifuge comes to a stop, test the temperature of the tube contents without disturbing the oil water interface.
9. If the temperature of the sample is 125º F or above, read and record the combined sediment and water content at the bottom of each tube. If the temperature is below 125º F, the tubes must be reheated and the test repeated without further agitation until two consecutive consistent readings are obtained.
10. If an emulsion is visible, add a solvent containing a demulsifier to the sample and retest it.
11. Compare the readings from the two tubes. If the results vary by more than one subdivision of the centrifuge tube, the sample was not homogeneous. Thus the test should be repeated with two fresh samples. By following the procedure closely, the results obtained will be reliable and accurate.
CALCULATION:
1. Record the final volume of water and the sediment in each tube and take the average.2. Express the average as a percentage by volume of water and the sediment.
Sample Size
If the centrifuge tube is filled with any proportion other than 50/50 sample/solvent, the results cannot be read directly from the centrifuge tube. The following equation must be utilized to adjust for the incorrect mixture.
Sediment and Water % = (S/V) * 100
Where:S = Volume of sediment & water found, mlV = Volume of oil tested, ml
RESULT:
The amount of sediments present in the given sample is found to be ............. %
11. DETERMINATION OF FLASH POINT AND FIRE POINT BY OPEN CUP APPARATUS
AIM:
To determine the flash point and fire point of the given lubricant or liquid petroleum products.
APPARATUS REQUIRED:
Open cup apparatus, LPG supply, testing sample, thermometer etc.
THEORY:
Flash point is the lowest temperature at which sufficient amount of vapor are given off by an oil, so us to give a flash. When the vapor come into contact with test flame.
Fire point is the lowest temperature at which the vapor of oil burn continuously for at least 5 seconds. When a small flame is brought near it. Generally the fire point is 5-40 C higher than the flash point. Though these points are not released to the lubricating properties of oil, knowledge of these is helpful to provide safety measures against the
fire hazards during and storage.
This test method is applicable to all petroleum products with flash points above 79°C (175°F) and below 400°C (752°F) except fuel oils
PROCEDURE:
1. The cup is cleared using a solvent to remove oil and dried well.2. The cup is filled with the test oil up to the indicator level.3. The thermometer is immersed into the cup and the test flame in it. The heating device
is switched on and the temperature of the sample is carefully is greased by 2-3 degree c per minute.
4. The sample in the cup is well stirred constantly to keep the temperature uniform throughout.
5. A test flame is introduced into the cup at every 1 degree c rise in temperature.6. The temperature at distinct flash is seen in the interior of the cup is noted as the flash
point.7. The heating of the sample and the periodical introduction of the test flame are
continued. 8. When the oil vapor catches flame and continues to burn at least 5 seconds; the
temperature of the oil is noted and it is taken as fire point.
TABULATION:
S.No Name of the Sample Flash point in degree c Fire point in degree c
Fig shows Cleveland apparatus
RESULT:
The flash point of the given petroleum product is _______
The fire point of the given petroleum product is _______
12. DEAN AND STARK APPARATUS
AIM:
To determine the water in the given crude sample.
APP ARATUS:
A glass distillation flask, condenser, graduated glass tube and heater.
CHEMICALS REQUIRED:
A suitable solvent can be used (benzene or xylene).
THEORY:
Knowledge of the refining, purchase, water by distillation sediment-by-extraction the
water content of crude is important for sale and transport of crude oil. The result of is in
percent by volume, and the result of is in percent by weight.
PROCEDURE:
1. Measure the crude oil sample in a graduated cylinder.
2. The sample size shall be selected as indicated in Table A based on the expected water
content of the sample.
3. Weigh the cylinder empty and after filled with crude to determine the weight of the
sample.
4. Take care in pouring the sample slowly into the graduated cylinder to avoid trapping
air.
5. Carefully pour the sample slowly into the distillation flask.
6. Measure 400 ml of solvent in a graduated cylinder.
7. Flush the graduated cylinder containing the crude three times with solvent and add the
rinsings to the flask containing the crude, then add the rest of the solvent to the flask.
8. Assemble the apparatus as shown in the Fig. circulate water, at 20-25°C, through
condenser jacket.
9. Apply heat to the flask slowly (to prevent bumping and loss of water in the system),
condensate shall not be allowed to proceed higher than, three quarters of the distance
up the condenser inner tube.
10. After the initial heating adjust the rate of boiling so that the condensate proceeds to no
more than three quarters of the distance up the inner tube of the condenser.
11. Continue the distillation until no water is visible in any part of the apparatus except in
the trap and the volume of water in the trap remains constant for at least 5 minutes.
12. If there is a persistent accumulation of water droplets in the condenser inner tubes
flush it with solvent. The addition of an oil-soluble emulsion breaker at a
concentration of 1000 ppm to the xylene wash helps dislodge the clinging water
drops. After flushing redistill for 5 minutes.
13. When the carry-over of water is complete, allow and contents to cool to 20°C.
CALCULATION AND REPORTING :
Calculate the water in the sample according to the following equations:
Volume % is = (vol . of water∈trap ,ml )−(solvent blank , ml)
vol . of test sample mlX 100
=(vol . of water∈trapml)−(solvent blank ,ml )
mass of weighted crude∈gmdensity of crude gm /ml
X 100
Weight % is ¿(vol. of water ∈trap ml)−(solvent blank ,ml )
mass of weighed crude sample∈gmX 100
TABLE A: sample size selection
RESULT:
Expected water content (Mass or vol. %)
Approximate sample size (gm or ml)
50.1 - 100 25.1 - 50.0 10.1 - 25.05.0 - 10.0 1.1- 5.00.1 -1.0 less than 0.5
5102050100200200
13. MEASUREMENT OF KINEMATIC VISCOSITY USING U-TUBE VISCOMETER
AIM:
To determine the kinematic viscosity and dynamic viscosity by using u-tube viscometer.
APPARATUS:
U-tube viscometer Viscometer thermostat and bath A rubber bung A stop watch
THEORY:
Kinematic viscosity (V): is a measure of the resistance to gravity flow of a fluid, the pressure head being proportional to its density.
The unit used is the stoke which equals cm2/sec, the common unit used the centistoke = 10-2 stokes.
PROCEDURE:
1. Place the viscometer vertically into the bath liquid such that the filling mark A is 3 cm below the surface of the water.
2. Allow the viscometer to reach the bath temperature and then pour sufficient amount of the filtered crude into the filling tube to a point just below the filling mark A avoiding wetting the glass above A.
3. Allow the crude to flow through the capillary taking care that the liquid column remains unbroken until it reaches a position about 5 mm below the filling mark B and stop its flow by closing the timing tube with the rubber bung.
4. Add more crude to the filling tube to bring the crude level to just below mark A.
5. Wait for 30 minutes to allow the sample to reach the bath temperature and any air bubbles to rise to the surface.
6. Open the timing tube slightly to allow the crude level to rise to mark B and close it again add more crude to the filling tube to bring its level to mark A, wait for 5 minutes.
7. Open the timing tube and allow the liquid to flow under its own head and measure the time in seconds for the upper most level of the crude to rise from mark C to mark D.
CALCULATIONS AND REPORT:
1- Calculate the kinematic viscosity V from the measured flow time t and the instrument constant by means of the following equation.
V = C t
where, V = kinematic viscosity, centistokes, C = calibration constant of the viscometer, centistokes per second, and t = flow times, seconds.
2- Calculate the viscosity µ from the calculated kinematic viscosity V and the density P by means of the following equation µ = pV
where, µ = dynamic viscosity in centipoises P = density, grams per cubic centimetre at the same temperature used for Measuring the flow time t, and V = kinematic viscosity, centistokes.
3- Report test results for both the kinematic and dynamic viscosity rounded to the nearest one part per thousand of the value measured or calculated, respectively.
RESULT:The dynamic viscosity and kinematic viscosity of the given sample is found to be --------
