AN

INDUSTRIAL TRAINING REPORT ON

RAMA NEWSPRINT AND PAPER

LIMITED

VILLAGE: BARBODHAN, TAL:OLPAD, DIST:SURAT,GUJARAT (INDIA)

   

PREPARED BY

Mr. SANTOSH KUMAR SHRIWASTAV

AURA MANAGEMENT STUDIES(Instrumentation & control

department)

 TRANING DURATION 28TH MAY

TO 27TH JUNE 2012

SR.NO. CONTENTS SLIDE NO.

01 Company profile 5 TO 8

02 Deinking Plant Flow Chart

9 &10

03 Paper machine Flow Chart

11

04 Instrumentation 12 TO 55

05 UITILITY 56 TO 72

TOTAL NO. OF SLIDE – 1 TO 72

ACKNOWLEDGEMENT

We would like to express our sincere thanks to management of RNPL and deep sense of acknowledgment to Mr. R.K CHAKRABORTY,.G.M. (ELEC. & INST.) for permitting us to undergo industrial training in esteem company RAMA NEWSPRINT AND PAPER LIMITED. We express our heartiest gratitude and are greatly indebted to our training guides Mr.N.K TRIPATHI AND Mr. ASHOK PATEL (Sr. manager of instrumentation) discipline for their valuable guidance for fulfilling the objective of this training. They stood by us right from the beginning to the end of training encouraging us in all manners. They have guided us right from the beginning till end and helped us understand the role of instrumentation in a big process plant. They were always there to clarify out doubts.The vocational training has helped us to get acquainted with practical side of instrumentation and control.

The training has helped us in many ways. It has made us aware of the

responsibilities of an instrumentation & control engineer. The training has

exposed us to importance of safety and how its being implemented in

Barbodhan plant.This training exposed to the latest instrumentation technologies being utilized at the Barbodhan Plant. The training has made us more confident

about facing the future.

Company profile

Rama News & Paper mill is India’s largest private sector company & it is established in 1996 by Mr. Vasu Singhania. The company meets 22% of India’s newsprint production capacity..

It is fully integrated paper mill. It’s totally integrated for manufacture of paper and pulp with modern wide width high speed paper machine besides in house conversion facilities to address customers specific requirement.

  At RNPL the technology is based on recycling of used

paper and a process that is devoid of using chlorine and other such chemicals ab\nd thereby making it a 100% ecology and environoment friendly paper plant(ETP) ensures preservation of environment. A highly advance, ultramodern, state-of-the-art laboratory maintains stringnent quality control and also conducts research and development for continuous product improvisation

Company profile

A 23 MW capacity powerplant ensure continuous operation of the mill without any interruption due to powercut.The in house engineering facilities help speedy implementation of improvisation in the operation to maintain our quality standards. It has installed DCS/ QCS for efficient and accurate control. The company has a private take in well on the river which pumps the water through a 17 Km long pipe line to the mill.

  The company manufactures about 1,32,000 tonnes per

annum of Newsprint or 1,80,000 tonnes per annum of Printing and writing paper or a mix of both. The company has turnover of about Rs. 288 crore for the accounting year 2007-2008.

Deinking Plant

Slat Conveyer

HC Pulper

Fiberizer

Buffer Tank

Drum Screen

Dump Tower

H.D. Cleaner

Pri. Coarse Screen

L.C. Cleaner 2nd Stage

L.C. Cleaner 1st Stage

Multi Sorter Feed Chest

Multi Sorter

L.C. Cleaner 3rd Stage

Ter-coarse screen feed

chest

Tex-Coarse Screen

Diabola Pre Floatation Primary Eco gaus#1

Foam Tank

Floatation#1 secondary

To Paper m/c

Primary Fine Screen Feed Chest

Primary Fine Screen

Disc Filter #1

M/C Pump #1

Dewatering Press

Steam Mixture

Krima Discharge

Peroxide Tower

Discharge & Dilution Screw

L. C. Pump

Intermediate Chest

Post Floatation Primary

Disc Filter #2

M/C Pump #3

AHL Mixer

Hydrosulphite Bleaching Tower

H.D. Tower

Secondary Fine Screen Feed Chest

Secondary

Fine Screen

Tertiary Fine Screen Feed

Chest

Mini Sorter

Screw Press

Plug Screw

Eco Gaus #2

Foam Tank #2

Post Floatation Secondary

Paper Machine Flow Process

Deinking pulp

Stock Preparation Chemicals

Broke (reuse paper)

Centrifugal Cleaner Reject (Heavy particle)

Reject (size wise) Primary Cleaner

Head Box

Wire Part

Press Part

Dryers

Size Press (PM-2)

Dryers

Calender

Paper Reel Rewinder Finishing House

Instrumentation

LEVEL MEASUREMENT Level measurement is one of the oldest

measurements. Liquid level refers to the position or height of a liquid surface above a datum line. Level measurements are made to ascertain the quantity of the liquid held within a container. The measurement of industrial process level parameters is of great importance in the industrial field. Level affects both the pressure and rate of flow in and out of the container and as such its measurement and/or control is an important function in a variety of processes. Hence, the quality may be affected in case of error in the process fluid level.

Here, different methods of level measurement have been discussed with their merits and demerits.

The sight glass (also called a gauge glass) is one of the widely used instruments. It is used for continuous indication of liquid level within a tank.

It consists of a graduated tube of toughened glass which is connected to the interior of the tank at the bottom in which the water level is required.

Liquid level in the glass tube matches the level of liquid in the tank. As the level of liquid in the tank rises and falls, the level in the sight glass also rises and falls accordingly. Thus, by measuring the level in the sight glass, the level of the liquid in the tank is measured.

Ranges:- The standard practice is not to go in for a glass tube of more than 900

mm length. In case the height of the tank is more than 900 mm, two or more sight glass level gauges are provided at different levels.

FLOW MEASUREMENT

Measurement of flow rate and quantity is the oldest of all measurements of process variables in the field of instrumentation. Measurements of fluid

velocity, flow rate and flow quantity with varying degree of accuracy are a fundamental necessity in almost all the flow situations of engineering

importance. It is made for determining the proportions and the amount of materials entering or leaving a continuous manufacturing process. Studying

ocean or air currents, monitoring gas input into a vacuum chamber, metering materials in a pilot plant, or detecting and measuring blood movement in a vein, the scientist or engineer is faced with choosing a method to measure

flow. For experimental procedures, it may be necessary to measure the rates of flow either into or out of the engines; pumps, compressors and turbines;

steam generators and all heat transfer apparatus. Without flow measurements, plant material balancing, quality control and even the

operation of any continuous process would be almost impossible. For the purpose of cost accounting, such measurement is often required to be made

for steam, water and gas services to domestic consumers, and in the gasoline pumping stations. Flow measurements are made both for fluids and

solids.Flow measurements are made both for fluids and solids. Here, different

methods of flow measurement have been discussed with their merits and demerits.

PRESSURE MEASUREMENT

Pressure measurement is undoubtedly one of the most common of all the measurements made on systems. In company with temperature and flow, pressure measurements are extensively used in industry, laboratories and many other fields for a wide variety of reasons. Pressure measurements are concerned not only with determination of force per unit area but are also involved in many liquid level, density, flow and temperature measurements. Measurement of pressure is also needed to maintain safe operating conditions, to help control a process and to provide test data. Nearly all industrial processes use liquids, gases or both. Controlling these processes requires the measurement and control of liquid and gas pressures. Thus, pressure measurement is one of the most important of all process measurements.

MEASURING LIQUID LEVELOpen Vessels:-

Pressure transmitters, when used for liquid level, measure hydrostatic pressure head.

This pressure is equal to the liquid height above the tap multiplied by the specific gravity of the liquid. It is

independent of volume or vessel shape.For open vessels, a pressure transmitter mounted on near

the bottom of the tank will measure the pressure corresponding to the height of the liquid above it.

Pressure is sensed by the process flange and transmitted to the high pressure side of the sensing element.

The low pressure side of the sensing element is vented to atmosphere.

If it is desired to have a zero reference at point above the location of the range must be performed.

MEASURING LIQUID LEVELClosed Vessels:-

For closed vessels, pressure inside the vessel (above the liquid) will affect the pressure measured at the bottom; pressure sensed at the bottom is equal to the height of the liquid, multiplied by the specific gravity of the liquid, plus the vessel

pressure.To measure true level, vessel pressure must be subtracted from the measurement.

This accomplished by making a pressure tap at the top of the vessel connected to the low pressure side of the transmitter. Vessel pressure is equalized at the high and low sides of the transmitter. The resulting differential pressure is proportional to the liquid

height multiplied by the specific gravity.Differential capacitance between the sensing diaphragm and the capacitor plates is electronically converted to a two –wire, 4-20 or 10-50 mA dc output signals directly

proportional to pressure. This approach is based on the following concept:P = K (C1-C2)/ (C1+C2)

Where: P = process pressure

K = constant.C1 = capacitance between the sensing diaphragm and the high

pressure side.C2 = capacitance between the sensing diaphragm and the low pressure side.

Temperature measurement Temperature is probably the most fundamental parameter, and is a

widely measured and frequently controlled industrial variable. It is required in the routine control of an industrial plant. Measurement of temperature potential is involved in thermodynamics, heat transfer and many chemical operations. The conditions, under which temperature has to be measured, differ so widely that no fixed rule can be followed. All that is essential is that one should select the most appropriate method of temperature measurement for a particular use. Basically all the properties of matter such as size, color, electrical and magnetic characteristics, and the physical states (i.e. solid, liquid and gas) change with changing temperatures. The occurrence of physical and chemical changes is governed by the temperature at which a system is maintained. During the selection of the method to measure temperature, one must consider the points such as, sources of error or limitations, precautions to be observed, the exact location of the sensing probe, etc. The steps to be taken to check the accuracy of instruments before, during, and after the test are also of extreme importance.

Here, different methods of temperature measurement have been discussed with their merits and demerits.

THERMOCOUPLE Temperature Range

Platinum RTD's are capable of measuring from -450 °F to 1200 °F.

Thermocouple ranges are

32 to 1400 °F for Type J.

-328 to 2,300 °F for Type K.

-328 to 660 °F for Type T.

32 to 2300 °F for Type N.

32 to 2640 °F for Type R

1472 to 3092 °F for Type B.

Principle:

The working principle of a thermocouple, which depends on the thermo-electric effect, was first observed by Seebeck in 1821 and is known as Seebeck effect.

If two dissimilar metals are joined together so as to form a closed circuit, there will be two junctions where they meet each other. If one of these junctions is heated, then, a current flows in the circuit which can be detected by a galvanometer.

The amount of the current produced depends on the difference in temperature between the two junctions and on the characteristics of the two metals.

The emf produced per degree of temperature change must be sufficient to facilitate detection and measurement. The emf of a simple thermocouple circuit is generally given by the following equation:

E = At+Bt2/2+Ct3/3 Where, t = temperature in 0C E = emf produced A, B, C = constants dependent on the thermocouple material

Check the accuracy of the thermocouple over the measured range.

For example the accuracy of a Type K thermocouple is

2% of reading from –328 to –166°F, 4°F from –166 to 559°F

and ¾% from 559 to 2282°F. 

Look at the sensor signal change over the measured temperature range to see the different

sensitivities and non-linearities.

TYPE J THERMOCOUPLE (Iron/Constantan)

  Composed of a positive leg which is iron and a negative leg

which is approximately 45 % nickel-55% copper. (Note - Constantan is Copper-Nickel.)

  When protected by compacted mineral insulation and

appropriate outer sheath, Type J is useable from 0 to 816°C, (32 to 1500°F). It is not susceptible to aging in the 371 to 538°C, (700 to 1000°F) temperature range. A drift rate of 1 to 2°C, (2 to 4°F) occurs with Type E and K in the 371 to 538°C, (700 to 1000°F) temperature range. This low cost, stable calibration is primarily used with 96% pure MgO insulation and a stainless steel sheath.

Thermocouple Grade- 32°F to 1382°F, 0 to 750°C Extension Grade- 32°F to 392°F, 0 to 200°C

TYPE K THERMOCOUPLE (Chromel / Alumel)

Composed of a positive leg, which is approximately 90% nickel, 10 chromium and a negative leg, which is approximately 95% nickel, 2% aluminum, 2% manganese and 1% silicon.

Due to its reliability and accuracy, Type K is used extensively at temperatures up to 1260°C (2300°F). It's good practice to protect this type of thermocouple with a suitable metal or ceramic protecting tube, especially in reducing atmospheres. In oxidizing atmospheres, such as electric furnaces, tube protection is not always necessary when other conditions are suitable; however, it is recommended for cleanliness and general mechanical protection. Type K will generally outlast Type J because the JP (iron) wire rapidly oxidizes, especially at higher temperatures.

TYPE T THERMOCOUPLE (Copper / Constantan)

Composed of a positive leg, which is approximately 90% nickel, 10 chromium and a negative leg, which is approximately 95% nickel, 2% aluminum, 2% manganese and 1% silicon.

When protected by compacted mineral insulation and appropriate outer sheath, Type T is usable from 0 to 350°C, (32 to 662°F). Type T is very stable and is used in a wide variety of cryogenic and low temperature applications. For applications below 0°C, (32°F) special selection of alloys are usually required.

TYPE N THERMOCOUPLE (Nicrosil / Nisil)

Type N (Nicrosil�Nisil) (nickel-chromium-silicon/nickel-silicon) thermocouples are suitable for use between -270 °C and 1300 °C owing to its stability and oxidation resistance. Sensitivity is about 39 �V/°C at 900 °C, slightly lower compared to type K.

When protected by compacted mineral insulation and appropriate outer sheath, Type N is useable from 0 to 1260°C, (32 to 2300°F). Type N was developed to overcome several problems inherent in Type K thermocouples. Aging in the 316 to 593°C, (600 to 1100°F) temperatures is considerably less. Type N has also been found to be more stable than Type K in nuclear environments.

TYPE R THERMOCOUPLE (Platinum / Rhodium)

Composed of a positive leg which is approximately 70% Platinum, 30% Rhodium and a negative leg which is approximately 94% Platinum, 6% Rhodium.

When protected by compacted mineral insulation and appropriate outer sheath, Type R is usable from 0 to 1482°C, ( 32 to 2700°F).Type R has a higher EMF output than type S. Also easily contaminated, and damaged by reducing atmospheres. Type R should by protected in a similar fashion as Type S.

TYPE B THERMOCOUPLE (Platinum / Rhodium)

Composed of a positive leg which is approximately 14% chromium, 1.4% Silicon and 84.6% Nickel, a negative leg which is approximately 4.4% Silicon, 95.6% Nickel.

When protected by compacted mineral insulation and appropriate outer sheath, Type B is usable from 871 to 1704°C, (1600 to 3100°F). Also easily contaminated, and damaged by reducing atmospheres. The same protective measures as shown above apply to type B Thermocouples.

TYPE E THERMOCOUPLE (Chromel / Constantan)

Composed of a positive leg, which is approximately 90% nickel, 10 chromium and a negative leg, which is approximately 95% nickel, 2% aluminum, 2% manganese and 1% silicon.

When protected by compacted mineral insulation and appropriate outer sheath, Type E is usable from 0 to 900°C, (32 to 1652°F). This Thermocouple has the highest EMF output per degree of all recognized thermocouples. If the temperature is between 316 to 593°C, (600 to 1100°F), we recommend using type J or N because of aging which can cause drift of 1 to 2°C, (2 to 4°F) in a few hours time. For applications below 0°C, (32°F), special selection of alloys are usually required.

TYPE S THERMOCOUPLE (Platinum / Rhodium)

  Composed of a positive leg which is

approximately 70% Platinum, 30% Rhodium and a negative leg which is approximately 94% Platinum, 6% Rhodium.

When protected by compacted mineral insulation and appropriate outer sheath, Type S is usable from 0 to 1482°C, (32 to 2700°F). Easily contaminated. Reducing atmospheres are particularly damaging. Type S should be protected with gas tight ceramic tubes, a secondary tube of porcelain and silicon carbide or metal outer tubes, as conditions require.

RTD Resistance Temperature Detector (RTD) Every type of metal has a unique composition and has a different resistance to the flow of electrical current. This is termed the resistively constant for that metal. For most metals the change in electrical resistance is directly proportional to its change in temperature and is linear over a range of temperatures. This constant factor called the temperature coefficient of electrical resistance (short formed TCR) is the basis of resistance temperature detectors. The RTD can actually be regarded as a high precision wire wound resistor whose resistance varies with temperature. By measuring the resistance of the metal, its temperature can be determined. Several different pure metals (such as platinum, nickel and copper) can be used in the manufacture of an RTD. A typical RTD probe contains a coil of very fine metal wire, allowing for a large resistance change without a great space requirement. Usually, platinum RTDs are used as process temperature monitors because of their accuracy and linearity. To detect the small variations of resistance of the RTD, a temperature transmitter in the form of a Wheatstone bridge is generally used. The circuit compares the RTD value with three known and highly accurate resistors.

RTD

A Wheatstone bridge consisting of an RTD, three resistors, a voltmeter and a voltage source is illustrated in Figure 1. In this circuit, when the current flow in the meter is zero (the voltage at point A equals the voltage at point B) the bridge is said to be in null balance. This would be the zero or set point on the RTD temperature output. As the RTD temperature increases, the voltage read by the voltmeter increases. If a voltage transducer replaces the voltmeter, a 4-20 mA signal, which is proportional to the temperature range being monitored, can be generated. As in the case of a thermocouple, a problem arises when the RTD is installed some distance away from the transmitter. Since the connecting wires are long, resistance of the wires changes as ambient temperature fluctuates. The variations in wire resistance would introduce an error in the transmitter. To eliminate this problem, a three-wire RTD is used.

Bourdon Tube Pressure Gauge

Principle

The Bourdon tube is the most frequently used mechanical type pressure gauge because of its simplicity and rugged construction.

The action of the Bourdon gauge is based on the deflection of a hollow tube caused by the applied pressure difference.

It covers ranges from 0-15 psig to 0-100,000 psig, as well as vacua from 0 to 30 inches of mercury.

Construction and Working The pressure responsive element of a Bourdon gauge consists essentially

of a metal tube, called Bourdon tube, oval in cross-section and bent to form a circular segment of approximately 200 to 300 degrees.

One end of the tube is closed but free to allow displacement under deforming action of the pressure difference across the tube walls.

The other end of the tube is fixed and is open for the application of the pressure which is to be measured.

The tube is soldered or welded to a socket at the base, through which pressure connection is made.

The figure shows the schematic arrangement of a complete Bourdon tube gauge.

As the fluid under pressure enters the Bourdon tube, it tries to change the section of the tube from oval to circular, and this tends to straighten out the tube with a consequent increase in its radius of curvature i.e. free end moves away from the centre.

The free end of the tube is connected to a spring loaded linkage which amplifies the displacement and transmits it to the angular rotation of a pointer over a calibrated scale to give a mechanical indication of pressure.

continue The tip of the Bourdon tube is connected to a segmental lever through an

adjustable length link. The lever length also may be adjustable. The segmental lever end on the segment side is provided with a rack which

meshes to a suitable pinion mounted on a spindle. The segmental lever is suitably pivoted and the spindle holds the pointer, as shown in figure.

A hairspring is sometimes used to fasten the spindle to the frame of the instrument to provide the necessary tension for proper meshing of the gear teeth, thereby freeing the system from backlash (lost motion). Any error due to friction in the spindle bearing is known as ‘lost motion’.

Bourdon tubes are made of a number of materials, depending upon the fluid and the pressure for which they are used, such as phosphor bronze, alloy steel, stainless steel, ‘Monel’ metal, and beryllium copper. The material chosen to fabricate a Bourdon tube will relate to the instrument sensitivity, accuracy and precision.

For adequate reliability, the materials for Bourdon tubes must have good elastic or spring characteristics.

Bourdon tubes are generally made in three shapes: C-type Helical type Spiral type

DEAD WEIGHT TASTER GAUGE

RANGE – 2.0 TO 100,200,250

KG/CM² WEIGHT SET – (MASS SET ) 20KG

TO 49 KG (DEPENDENT ON PRESSURE GAUGE

BASE UNIT – 20KG/CM²

WEIGHT SET – BLOCKO DIZE MS OR STAINESS STEAL

ORIFICE PLATE

The different types of orifice plates are :

•    Concentric.

•    Segmental.

•    Eccentric.

•    Quadrant Edge.

Concentric : The concentric orifice plate

is used for ideal liquid as well as gases and steam service. This orifice plate  beta  ratio fall between of 0.15 to 0.75 for liquids and 0.20 to 0.70 for gases, and steam. Best results occur between value of 0.4 and 0.6. beta ratio means ratio of the orifice bore to the internal pipe diameters.

(45º beveled edges are often used to minimize friction resistance

to flowing fluid )

Eccentric :

The eccentric orifice plate has a hole eccentric. Use full for measuring containing solids, oil containing water and wet steam. Eccentric plates can use either flange or vena contracta taps, but the tap must be at 180º or 90º to the eccentric opening.

Eccentric orifices have the bore offset from center to minimize problems in services of solids-containing materials.

Segmental :

The segmental orifice place has the hole in the form segment of a circle. This is used for colloidal and slurry flow measurement. For best accuracy, the tap location should be 180º from the center of tangency.

Segmental orifices provide another version of plates useful for solids containing materials.

Quadrant Edge :

It common use in Europe and are particularly useful for pipe sizes less than 2 inchs.

Quadrant edge orifices produce a relatively constant coefficient   of discharge   for  services   with  low Reynolds numbers  in the range from 100,000 down to 5,000.

The orifice plate Flow Detector is the simplest of the flow-path restrictions used in flow detection, as well as the most economical. Orifice plates are flat plates 1/16 to 1/4 inch thick. They are normally mounted between a pair of flanges and are installed in a straight run of smooth pipe to avoid disturbance of flow patterns from fittings and valves.

Three kinds of orifice plates are used: concentric, eccentric, and segmental (as shown in Figure F1).

The concentric orifice plate is the most common of the three types. As shown, the

orifice is equidistant (concentric) to the inside diameter of the pipe. Flow through a sharp-

edged orifice plate is characterized by a change in velocity. As the fluid passes

through the orifice, the fluid converges, and the velocity of the fluid increases to a

maximum value. At this point, the pressure is at a minimum value. As the fluid diverges to

fill the entire pipe area, the velocity decreases back to the original value. The

pressure increases to about 60% to 80% of the original input value. The pressure loss is irrecoverable; therefore, the output pressure will always be less than the input pressure.

The pressures on both sides of the orifice are measured, resulting in a differential pressure

which is proportional to the flow rate.

Segmental and eccentric orifice plates are functionally identical to the concentric orifice. The circular section

of the segmental orifice is concentric with the pipe. The segmental portion of the orifice eliminates damming of

foreign materials on the upstream side of the orifice when mounted in a horizontal pipe. Depending on the type of fluid, the segmental section is placed on either the top or bottom of the horizontal pipe to increase the

accuracy of the measurement.Eccentric orifice plates shift the edge of the orifice to the inside of the pipe wall. This design also prevents

upstream damming and is used in the same way as the segmental orifice plate.

 Orifice plates have two distinct disadvantages; they

cause a high permanent pressure drop (outlet pressure will be 60% to 80% of inlet pressure), and they are

subject to erosion, which will eventually cause inaccuracies in the measured differential pressure.

How do orifice plates work ?

An orifice plate installed in a line creates a pressure differential as the fluid flows through it. This differential pressure is measured via impulse lines by a differential pressure transmitter which converts it into an analogue or digital signal which can be processed to provide a display of the instantaneous rate of flow. The relationship between the rate of flow and the differential pressure produced is very well understood and is fully covered by comprehensive national standards. The relevant standards are BS 1042 and the equivalent

MULTIMETER

What do meters measure? A meter is a measuring instrument. An ammeter

measures current, a voltmeter measures the potential difference (voltage) between two points, and an ohmmeter measures resistance. A multimeter combines these functions, and possibly some additional ones as well, into a single instrument.

A multimeter is an instrument used to check for AC or DC voltages, resistance or continuity of electrical components and small amounts of current in circuits. This instrument will let you check to see if there is voltage present on a circuit, etc. Here's how to use an analog multimeter.

MULTIMETER Jacks or openings in the case to

insert test leads. Most multimeters have several jacks. The one pictured has just two. One is usually labeled "COM" or (-) ,for common and negative. This is where the black test lead is connected. It will be used for nearly every measurement taken. The other jack(s) is labeled "V" (+) and the Omega symbol (an upside down horseshoe) for Volts and Ohms, respectively, and positive. The + and - symbols represent the polarity of probes when set for and testing DC volts. If the test leads were installed as suggested, the red lead would be positive as compared to the black test lead. This is nice to know when the circuit under test isn't labeled + or -, as is usually the case. Many meters have additional jacks that are required for current or

The pointer or needle: This is the thin black line at the left-most position in the dial face window in the image. The needle moves to the value measured.Arc shaped lines or scales on the meter dial face: These may be different colors for each scale, but will have different values. These determine the ranges of magnitude.A wider mirror-like surface shaped like the scales mentioned previously might also be present. The mirror is used to help reduce parallax viewing error by lining up the pointer with its reflection before reading the value the pointer is indicating. In the image, it appears as a wide gray strip between the red and black scales.A selector switch or knob: This allows changing the function (volts, ohms, amps) and scale (x1, x10, etc.) of the meter. Many functions have multiple ranges. It is important to have both set correctly, otherwise serious damage to the meter or harm to the operator may result. Most meters employ the knob type like the one shown in the image, but there are others. Regardless of the type, they work similarly. Some meters (like the one in the image above) have an "Off" position on this selector switch while others have a separate switch to turn the meter off. The meter should be set to "Off" when stored.

jacks as it is to have the selector switch range and test type (volts, amps, ohms) set. All must be correct. Consult the meter manual if you're unsure which jacks should be used.Test leads: There should be (2) test leads or probes. Generally, one is black and the other red.Battery and fuse compartment: Usually found on the reverse, but sometimes on the side. This holds the fuse (and possibly a spare), and the battery that supplies power to the meter for resistance tests. The meter may have more than one battery and they may be of different sizes. A fuse is provided to help protect the meter movement. Sometimes there is more than one fuse. A good fuse is required for the meter to function. Fully charged batteries will be required for resistance/continuity tests.Zero Adjustment: This is a small knob usually located near the dial that is labeled "Ohms Adjust", "0 Adj", or similar. This is used only in the ohms or resistance range, while the probes are shorted together (touching each other). Rotate the knob slowly to move the needle as close to the 0 position on the Ohms scale as possible. If new batteries are installed, this should be easy to do - a needle that will not go to zero indicates weak batteries that should be replaced.

CONTROL

INTRODUCTION

Control of the processes in the plant is an essential part of the plant operation. There must be enough water in the boilers to act as a heat sink for the reactor but there must not be water flowing out the top of the boilers towards the turbine. The level of the boiler must be kept within a certain range. The heat transport pressure is another critical parameter that must be controlled. If it is too high the system will burst, if it is too low the water will boil. Either condition impairs the ability of the heat transport system to cool the fuel. In this section we will look at the very basics of control. We will examine the fundamental control building blocks of proportional, integral and differential and their application to some simple systems.

BASIC CONTROL PRINCIPLES Consider a typical process control system. For a particular example let us look at an open tank, which supplies a process, say, a pump, at its output. The tank will require a supply to maintain its level (and therefore the pump.s positive suction head) at a fixed predetermined point. This predetermined level is referred to as the setpoint (SP) and it is also the controlled quantity of the system. Clearly whilst the inflow and outflow are in mass balance, the level will remain constant. Any difference in the relative flows will cause the level to vary. How can we effectively control this system to a constant level? We must first identify our variables. Obviously there could be a number of variables in any system, the two in which we are most interested are: The controlled variable - in our example this will be level. The manipulated variable . the inflow or outflow from the system. If we look more closely at our sample system (Figure 1), assuming the level is at the setpoint, the inflow to the system and outflow are balanced. Obviously no control action is required whilst this status quo exists. Control action is only necessary when a difference or error exists between the setpoint and the measured level. Depending on whether this error is a positive or negative quantity, the appropriate control correction will be made in an attempt to restore the process to the setpoint.

E/P CONVERTER

E/P CONVERTER PRINCIPLE

In order for an electronic control signal to operate a pneumatic instrument (such as an electronic controller operating valve), the electronic signal must be changed into pneumatic signal.

This is accomplished by using I/P converter or current to pneumatic transducer.

I/P converters accept 4 to 20 mA and provide a pneumatic output of 3 to 15 psi.

However, an essential characteristic of a transducer is that it is able to produce an output signal that is proportional to the input.

E/P CONVERTEROPERATION

Figure shows I/P converter in which a coil is positioned in the field of a fixed permanent magnet.

The coil magnet mechanism converts the signal to motion by the interaction of the two magnet fields.

One field surrounds the permanent magnet and the other field surrounds the force coil.

The magnetic field in the coil is produced due to the current flowing through the coil.

The lines of flux of the magnetic coil are concentrated in the magnet. An increase in the input current forces the coil to move because of the

intensified magnetic field surrounding the coil. A decrease in the current causes the coil to move in the opposite direction.

The coil movement changes the baffle-nozzle relationship. A change in the nozzle back pressure is sensed by a diaphragm in the relay. The

movement of diaphragm positions a valve. This valve position determines the signal output value from the relay.

A balance force on the beam is provided by the feed back bellows. A spring pivot provides a pivot point for the beam. As the coil moves up, the

baffle moves toward the nozzle.

I/P CAILIBRATION(Current Convert To Pressure)

% mA PRESSUREKG/CM²

PSI

0 4.00 0.2 kg 3

25 8.00 0.4kg 6

50 12.00 0.6kg 9

75 16.00 0.8kg 12

100 20.00 1.0kg 15INPUT – I/P – ( 4 TO 20)mAOUTPUT – I/P – ( 3 TO 15)

UITILITY DEPARTMENT

DM PLANT (Demineral Water Plant)

DEAERATOR

COAL PLANT

BOILER

TG

DM PLANT (Demineral Water Plant)

COAGULATION TANK DUAL MEDIA FILTERS(1&2) ACTIVATED CARBON(1&2) STRONG ACID CATION (1&2) DEGASER BLOWER DEGASER TANK STRONG BASE ANION MIXED BED (1&2) DM STORAGE TANK CONDENSATE STORAGE TANK DEAERATOR FEED PUMPS

The following ions are widely found in raw waters:

Cations Anions

Calcium (Ca2+) Chloride (Cl-)

Magnesium (Mg2+) Bicarbonate (HCO3-)

Sodium (Na+) Nitrate (NO3-)

Potassium (K+) Carbonate (CO32-)

Iron (Fe2+) Sulfate (SO42-)

DEAERATOR

A deaerator is a device that is widely used for the removal of oxygen and other dissolved gases from the feedwater to steam-generating boilers. In particular, dissolved oxygen in boiler feedwaters will cause serious corrosion damage in steam systems by attaching to the walls of metal piping and other metallic equipment and forming oxides (rust). Dissolved carbon dioxide combines with water to form carbonic acid that causes further corrosion. Most deaerators are designed to remove oxygen down to levels of 7 ppb by weight (0.005 cm³/L) or less as well as essentially eliminating carbon dioxide

TRY TYPE DEAERATOR Why gases need to be removed from boiler feedwater

Oxygen is the main cause of corrosion in hotwell tanks, feedlines, feedpumps and boilers. If carbon dioxide is also present then the pH will be low, the water will tend to be acidic, and the rate of corrosion will be increased. Typically the corrosion is of the pitting type where, although the metal loss may not be great, deep penetration and perforation can occur in a short period.

Elimination of the dissolved oxygen may be achieved by chemical or physical methods, but more usually by a combination of both.

The essential requirements to reduce corrosion are to maintain the feedwater at a pH of not less than 8.5 to 9, the lowest level at which carbon dioxide is absent, and to remove all traces of oxygen. The return of condensate from the plant will have a significant impact on boiler feedwater treatment - condensate is hot and already chemically treated, consequently as more condensate is returned, less feedwater treatment is required.

Water exposed to air can become saturated with oxygen, and the concentration will vary with temperature: the higher the temperature, the lower the oxygen content.

The first step in feedwater treatment is to heat the water to drive off the oxygen. Typically a boiler feedtank should be operated at 85°C to 90°C. This leaves an oxygen content of around 2 mg / litre (ppm). Operation at higher temperatures than this at atmospheric pressure can be difficult due to the close proximity of saturation temperature and the probability of cavitation in the feedpump, unless the feedtank is installed at a very high level above the boiler feedpump.

The addition of an oxygen scavenging chemical (sodium sulphite, hydrazine or tannin) will remove the remaining oxygen and prevent corrosion.

This is the normal treatment for industrial boiler plant in the UK. However, plants exist which,

COAL PLANT FLOW CHART

Coal Circuit

Coal Storage

Hopper

Magnetic Separator

Impact Crusher-1,2

Vibration Screen-1,2

Bunker-1,2

Coal Feeder-1 to 12

Coal Feeder Line with PA-1 to 24

Furnace

Coal plant

In RNPL there are two types of coal Indian Imported Indian coal Indian coal comes from the mines of Nagpur, Chandrapur . It

gives low calorific value compared to the second one. It absorbs low moisture so we can use it in monsoon also. It has approximately 5000 GCV per ton. It’s market price is nearly about 2700 Rs. Per ton.

Imported coal Imported coal comes from mines of China, Australia and

Indonesia. But this coal is used rapidly, because it gets the moisture from the atmosphere and burns. In addition to that this type of coal absorbed moisture more than the first one. So this types of coal not much prefer in monsoon. It’s approximately 6400 GCV per ton. It’s market price is about 3200 Rs. Per ton.

  In RNPL they use 400 tones daily.According to the requirement they use ratio of both coals like 50:50, 70:30 etc of Indian and imported.

BOILER

FAN RPM KW CAPCITY

ID FAN(INUCED DRAFT)

980 250 MOTOR KW

63.83 MTR 2/ PER SEC.

FD FAN(FORCE DRAFT)

1480 450 KW 44.78MTR 2/PERSEC.

PA FAN(PRIMARY

AIR)

2880 90 KW 6.85MTR 2/PER SEC.

BOILERS

Sl. No.

Description Item/Sectio

n

STEAMPressur

e (Kg/Cm2

)

STEAMTEMP.(oC)

BOILER CAPACITY

FURNECE TEMPH.

COAL BUNKAR CAPACITY

1 Multi-fuel Boiler(AP-2)

84 470oC 90 450 T

2 Multi-fuel Boiler(CE-4)

84 470oC 107 550 600 T

3 Oil fired Boiler(OK-8) 60

SAFETY INTERLOCK

DRUM LEVEL (LOW) DRUM LEVEL (HIGH)

40 % ------------- ALARM

70 % ------------- ALARM

30 % ----------------- TRIP

80 % -------------- TRIP

PA DEMPER FD DEMPER

SA DEMPER OVER FEEDING ROTARY FEEDER SCREW FEEDER

Ash Circuit

Flue Gas

+

Ash

Ash

+

Comp. Air

Ash

+

Water

Furnace

ESP

SILO

Creek

Air Circuit

Atm. Air

Coal Fluidising air

+

PA

Force Draft

Air Pre heater

Primary Air Tank

Furnace

Gas Circuit

Furnace

Bed Super Heater

Super Heater (Primary & Secondary)

Bank Tubes

Economizer

Air Pre Heater

ESP-1,2,3

Chimney (Through I.D. Fan)

Feed water Circuit

Condensate Storage Tank

Deaerator Feed pump

Boiler Feed pump

Economizer

Main Drum (water + steam)

Boiler Banks

Mud Drum (water)

Lower Header

Water Tubes

Upper Header

Steam Circuit

Secondary Fine Screen

Boiler Main Drum

Primary

Super heater

De - Super

heater

Secondary

Super Heater

De – Super

Heater

Bed Super

Heater

Main Steam

Line

84 kg/cm2

35 kg/cm2

11 kg/cm2

4 kg/cm2

To AEG Turbine

To Siemens Turbine

To Deaerator

To Process

Cooling Water Circuit

River (Tapi)

Pump No. 1, 2, 3

W T P

Pump 1, 2, 3, 4

Water Storage Tank

Cooling Water Storage

Pump -1, 2, 3

Condenser

Cooling Tower

Chemical Dosing

Make up Water

TG(BHEL) 23MW

KW 23000PF 0.8

FREQUENCY 50RPM 1500

VOLTS 11000AMPS 1509VOLTS 175AMPS 489

COOLING CACW

SAFETY INTERLOCK

1. TG TRIP AT LUB OIL PRESSURE IS VERY LOW. (0.85KG/CM2 )

2. REMOTE / MENNUAL TRIP FROM LOCAL PUSH BUTTON

3.AUTO START OF EOP (emergency oil pump) AT LUB OIL PRESSURE VERY LOW

4. CONTROL AIR PRESSURE IS VERY LOW (4KG/CM2

)