RECOVERY PLUS OPERATING MANUAL
Table of Contents1.0
General
1.1 Introduction 1.2 Glossary 1.3 Abbreviation2.0
Unit Description
2.1 Design Basis2.2 Process Flow Description and Controls 2.3 DCS Description
2.4 Design Flow Plan
2.5 Refinery Site, Underground Piping and Unit Layout Plan 2.6 Material Balance
2.7 Feed and Product Specifications 2.8 Catalyst and Chemicals Details 2.9 Utility conditions and requirement
3.0
Interconnectivity
3.1 Inter Unit Relationship 3.2 Inter Plant Relationship 3.3 Utility / Offsite Relationship
4.0
Preparing the Unit for Initial Start-up
4.1 Introduction
4.2 Utility System Readiness 4.2.1 Piping Network
4.2.2 Commissioning of Utilities 4.3 Inspection of Equipments 4.3.1 Piping and Supports
4.3.1.1 Visual Inspection 4.3.1.2 Hydrostatic Test 4.3.1.3 Flushing
4.3.1.4 Air Blowing and Drawing 4.3.1.5 Tightness Test 4.3.2 Vessels 4.3.3 Exchangers 4.3.4 Pumps 4.3.5 Compressors 4.3.6 Instrumentation System 4.3.7 Electrical System
4.4 Chemical Cleaning and N2 Blaketing 4.5 Run-in Pumps
4.6 Run-in Compressors
4.7 Tightness Test and Inertisation 4.7.1 Tightness Test
4.7.2 Vacuum Test and Inertisation 4.8 Safety Checks Before Start-up
5.0
Commissioning / Initial Start up
5.2 Utilities Start-up
5.3 Outline of Initial Start-up
5.4 Evacuation of Air, Nitrogen and Water Removal 5.5 Charging of Lube Oil
5.6 Oil Circulation
5.7 Inventory Refrigeration Circuit with Refrigerant 5.8 Initial Compressor Start-up
6.0
Start up
6.1 General
6.2 Notification to Other Departments 6.3 Utilities Start-up
6.4 Outline of Initial Start-up 6.5 Compressor Start-up
7.0
Normal Shutdown
7.1 General
7.2 Notification to Other Departments 7.3 Preshutdown Preparation
7.4 General Outline of Normal Shutdown 7.5 Refrigeration Circuit Shut Down 7.6 Process Circuit Shut Down 7.7 Refrigerant Retained in Receiver 7.8 Post Shutdown Checks
7.9 Equipment Handing/Taking Over to/from Maintenance
8.0
Normal Operation
8.1 Process Principles 8.2 Process Variables
8.3 Control Philosophy & Key Analyses
9.0
Unit Safeguarding System
9.1 Relief Device Summary 9.2 Instrument Alarm 9.3 Instrument Trip
10.0
Emergency Shutdown
10.1 General
10.2 Interconnectivity During Emergencies 10.3 Process and Utility Failure
10.3.1 Power Failure
10.3.2 Loss of Cooling Water 10.3.3 Loss of Refrigerant 10.3.4 Loss of Instrument Air
11.0 Special Procedures
11.1 Initial Refrigerant Loading
12.0
Fire & safety
12.1 Introduction
12.2 Repair Work, Permit to Work System, Housekeeping and Maintenance on
12.3 Safety During Sample Withdrawal 12.3 Fire Fighting and Safety Equipment
12.5 Precautions for Entering any Contaminated or Inert Atmosphere 12.6 General RECOVERY PLUS Unit Safety Notes
12.7 Material Safety Data Sheet (MSDS)
13.0 Laboratory Requirements and Schedule
14.0
Major Equipment and Instruments’ Summary
14.1.1 Vessels
14.1.2 Shell and Tube Exchangers 14.1.3 Pumps
14.2 Instruments Summary
15.0 List of Reference Drawings
PFD, P & ID, MFD, Plot Plan, PSFS, MSD, Area Protection Layout, Safety Equipment Layout, Safety Signs Layout, PIB#4 Gaseous Fire Extinguishing System
The Aromatics plant at Jamnagar is designed to produce 1,200,000 tons of Paraxylene per annum and 150,000 tons of Orthoxylene from naphtha feed stock (2641 KTPA) available from Jamnagar Refinery Complex and Mixed Xylenes (80 KTPA) from Hazira.
Feed Naphtha from the refinery consists of:
Straight run naphtha Delayed Coker naphtha FCC heart cut Naphtha
Paraxylene Plant basic technology has been provided by UOP. It will process special cut Naphtha (105 oC – 165 oC) to produce Paraxylene as the major product and other side cut products. These are as follows.
LPG = 305 TPD Light Reformate = 752 TPD Benzene = 326 TPD Toluene = 300 TPD Paraxylene = 3600 TPD Orthoxylene = 450 TPD
Paraxylene plant in Jamnagar consists of the following units:
1. Heavy Naphtha Unionfining Unit Unit No.221 2. Platformer Unit Unit No.231 3. Cyclemax Continuous Regeneration Unit Unit No.232 4. Recovery-Plus Unit No.233
5. PSA Unit No.234
6. Xylene fractionation unit (3 trains) Unit No.241/242/243 7. Orthoxylene fractionation unit Unit No. 251
8. Parex Unit (3 trains) Unit No. 261/262/263 9. Isomar Unit (3 trains) Unit No. 271/272/273 10. Tatoray Unit Unit No.281
11. Aromatics Tankage Unit No.201 12. Aromatic Blowdown Unit No.202
Key Features
As a part of the Jamnagar Refinery complex, aromatic plant is being established. A great emphasis has been placed on maximizing the ratio of Paraxylene to Benzene product. This serves to minimize the quantity of naphtha feed stock required per ton of Paraxylene product and avoids excess production of Benzene.
A key element of UOP’s strategy is to maximize Paraxylene to Benzene ratio by controlling the Naphtha initial points and end points upstream in the refinery. Heavy Naphtha feed stock for Platforming unit is obtained from three sources as follows.
Boiling range
a. Saturate Gas Concentration Unit Naphtha 105 to 165 oC b. Sydec Delayed coker Unit Naphtha 105 to 165 oC c. FCC heart cut naphtha 105 to 180 oC
For naphtha streams initial boiling point of 105 oC has been selected and a wide gap specified. This cut point, combined with a sharp fractionation, will serve to drive most of the C7 paraffin’s up into the light naphtha storage, but retain most of Toluene in the heavy naphtha to be used for aromatics production via Platforming units. The 105 oC cut point also eliminates Benzene precursors from the Platforming unit feed stock.
The end point of 165 oC will ensure that almost all C8 molecules and many C9 molecules will go into the heavy naphtha feed stock for aromatics production. To maximize Paraxylene production, it is important to retain all the C8 precursors and obtain just the right amount of C9 to generate enough C9 aromatics to fully load the Tatoray unit.
1.2 Glossary
Terms Description
Absorption - The process by which one substance draws into itself another substances i.e. CO2 absorbed in K2CO3 solution, HC absorbed in lean oil from net gas stream, etc.
Accumulator - A vessel for the temporary storage of a gas or liquid usually used for collecting sufficient material for a continuous charge to some refining process.
Adsorption - The physical separation of multiple components by solid adsorbent. i.e. removal of moisture, CO2 from air by air dryer using silica / alumina as adsorbent.
API - An arbitrary scale expressing the gravity or density of liquid petroleum products. The measuring scale is calibrated in terms of degrees API. It may be calculated in terms of the following formula :
Deg. API = (141.5/sp.gr. @60 °F) - 131.5
Aromatic - Derived from, or characterized by the presence of the benzene ring and having sweet odor. The name usually applied to the benzene series of hydrocarbons; derived from the characteristic odor of the series; Paraxylene, Ethyl Benzene(EB),
Terms Description
methyl benzene(TMB), Para di-ethyl benzene(P-DEB).
Aromatic Naphtha
- A naphtha rich in aromatics precursors
Atom - The smallest complete particle of an element which can be obtained which retains all physical and chemical properties of the element.
Atomize - To divide a liquid into extremely minute particles, either by impact with a jet of steam or compressed air, or by passage through some mechanical device.
Back pressure - 1. The pressure on the outlet or downstream side of a flowing system. 2. In an engine, the pressure which acts adversely against the piston, causing loss of power.
Barrel - A common unit of measurement of liquids in the petroleum industry; it equals 42 U.S. standard gallons.
Baume - Specific gravity of liquids expressed as degrees on the Baume scale. For liquids lighter than water, the formula is :
Sp. gr. 60 F/600 F = 140 /(130+deg. Be) For liquids heavier than water, the formula is : Sp. gr. 60 F/600 F = 145 / (145 - deg. Be)
Terms Description
Bleeding - Diverting a small portion of the material contained in a line or vessel, usually by opening a valve slightly. Blend - Any mixture prepared for a special purpose; e.g. the
products of a refinery are blended to suit market requirements.
Boiling Point - The temperature at which a substance boils or is converted into vapor by bubbles forming within the liquid; it varies with pressure.
Boiling Range - The range of temperature, usually determined at atmospheric pressure in standard laboratory apparatus over which the boiling or distillation of an oil commences, proceeds, and finishes.
Bottoms - The liquid which collects in the bottom of a vessel / column / tank during processing/storage. i.e. column bottom
Byproduct - A secondary or additional product produce during production of Major product, not of primary importance. i.e. Benzene byproduct in production of Paraxylene.
Calibration - Determination of the accuracy of an instrument by finding its variation from true measurement.
Carryover - 1. Relatively nonvolatile contaminating material which is carried over by the overhead effluent from a
Terms Description
fractionating column, absorber, or reaction vessel. It may be carried as liquid droplets or finely divided solids suspended in a gas/vapor/discrete liquid. 2. That portion of a finely divided catalyst which escapes the cyclones of cracking units.
Catalyst - A substance which affects, provokes, or accelerates reactions without itself being altered.
Caustic Soda - Sodium hydroxide, a very strong alkali.
Centrifugal Pump (Volute Type)
- Consists of one or more impellers mounted on a rapidly rotating shaft. The liquid enters the impellers at the center, or ‘eye’, and is thrown outward at a high velocity into the volute of the pump casing. The function of the volute is to catch the impeller discharge and convert velocity head into pressure head while conducting the liquid to the discharge nozzle of the pump casing.
Compressor - A machine which draws in air or other gas, compress it and discharges it at a higher pressure.
Condensation - The act or process of changing a vapor to a liquid, or a lighter liquid to another and denser form by depression of temperature or increase of pressure.
Terms Description
cooling and liquefying oil vapors. Where the cooling medium used is air, the condenser is called an air condenser.
Conduction - The flow of heat by contact.
Convection - The flow of heat through liquid or gas by actual mixing of the fluids
Cooler - A heat exchanger whose primary purpose is to reduce the temperature of one of the passing fluids.
Cracking - A phenomenon by which large oil molecules are decomposed into smaller, lower boiling molecules; at the same time, certain of these molecules, which are reactive, combine with one another to give even larger molecules than those in the original stock. The more stable molecules leave the system as cracked gasoline, but the reactive ones polymerize, forming tar and even coke.
Note: Cracking may be in either the liquid or vapor phase. When a catalyst is used to bring about the desired chemical reaction, this is called catalytic cracking; otherwise, it is assumed to be thermal cracking.
Crude Oil - A synonym for petroleum. A naturally occurring mixture consisting predominantly of hydrocarbons and/ or sulfur, nitrogen, and oxygen derivatives of
Terms Description
hydrocarbons which is removed from the earth in a liquid state or is capable of being, so removed.
Discharge Line - Product line usually under pressure due to a pumping force being applied.
Distillate - That portion of a liquid which is removed as a vapor and condensed during a distillation process.
Distillation - Vaporization of a liquid and its subsequent condensation in a different chamber. The separation of one group of petroleum constituents from another by means of volatilization in some form of closed apparatus, such as a still, by the aid of heat.
Drawoff - A connection which allows liquid to flow from the side or bottom of a vessel.
Effluent - Outflow from vessel/equipment/tank
Extraction - The process of separating a material, by means of a solvent, into a fraction soluble in the solvent (extract) and an insoluble residue.
Flammable - Capable of being easily set on fire; combustible.
Flash - 1. A sudden release in pressure resulting in partial or complete vaporization. 2. A sudden burst of light; a
Terms Description
momentary blaze.
Flash Point - The lowest temperature at which vapors arising from the oil will ignite momentarily (i.e. flash) on application of a flame under specified conditions.
Flooding - In a fractionating column, the filling up of a liquid due to high pressure drop across trays or packing.
Flue Gas - Gas from the combustion of fuel, the heating value of which has been substantially spent and which is therefore, discarded to the flue or stack.
Fuel Oil - Any liquid or liquefiable petroleum product burned for the generation of heat in a furnace or firebox, or for the generation of power in a engine (exclusive of oils with a flash point below 100 °F )
Header - A common manifold in which a number of pipelines are united.
Heat Exchanger
- Apparatus for transferring heat from one fluid to another. Specifically, a piece of equipment having a tubular piping arrangement which effects the transfer of heat from a hot to a relatively cool material by conduction through the tube walls.
Heater - The furnace -and- tube arrangement which is the principal heating element in a processing unit.
Terms Description
Hydrocarbon - A compound containing only hydrogen and carbon. The simplest hydrocarbons are gases at ordinary temperatures, but with increasing molecular weight, they change to the liquid form and finally to the solid state. They form the principal constituents of petroleum.
Impingement - The contact of flame on skin of radiant tubes in the furnace.
Induced Draft - Air drawn rather than forced into a furnace.
Inert gas - A noncombustible gas such as nitrogen or carbon dioxide.
Inhibitor - A substance the presence of which, in small amounts, in a petroleum product prevents or retards undesirable chemical changes from taking place in the product, or in the condition of the equipment in which the product is used. In general, the essential function of inhibitors is to prevent or retard oxidation or corrosion.
Knockout Drum - A drum or vessel constructed normally with baffles, through which a mixture of gas and liquid is passed to disengage one from the other. As the mixture comes in contact with the baffles, the impact frees
Terms Description
the gases and allows them to pass overhead; the heavier substance falls to the bottom of the drum.
Liquefied Petroleum Gas
- Light hydrocarbon material, gaseous at atmospheric temperature and pressure, held in the liquid state by pressure to facilitate storage, transport, and handling. Commercial LPG consists essentially of propane, butane, or mixtures thereof.
Manifold - A piping arrangement which allows one stream of liquid or gas to be divided into two or more streams, or which allows several streams to be collected into one.
Molecule - Unit of matter; the smallest portion of an element or a compound which retains chemical identity with the same particular substance enmasse.
Multi-Stage Centrifugal Pump
- Centrifugal pump which has two or more impellers mounted on the same shaft.
Naphthene - A saturated hydrocarbon having the general formula CnH2n and a cyclic molecular structure; i.e. cyclo-propane, cyclo-butane, cyclo-pentane, cyclohexane.
Natural Gas - Naturally occurring mixtures of hydrocarbon gases and vapors, the more important of which are methane, ethane, propane, butane, pentane, and hexane.
Terms Description
Olefin - An open chain, unsaturated hydrocarbon having one double bond.
i.e. Ethylene C2H4
Orifice - A device for restricting the flow through a pipe. The difference in pressure on the two sides of an orifice plate can be used to measure flow through the pipe.
Packed Tower - A fractionating or absorber tower which is filled with small objects (packing material, i.e. rasching ring,) to effect an intimate contact between rising vapor and falling liquid.
Paraffin - That series of noncyclic hydrocarbons having the general formula CnH2n + 2, and having no double & triple bonds. i.e. Butane C4H10 , Hexane
C6H14 , etc. .
Petrochemical Naphtha
- A naphtha lean in aromatics precursors
Petroleum - A material occurring naturally in the earth, predominantly composed of mixtures of chemical compounds of carbon and hydrogen with or without other nonmetallic elements such as sulfur, oxygen, nitrogen, etc. Petroleum may contain, or be composed of, such compounds in the gaseous, liquid,
Terms Description
and / or solid state, depending on the nature of these compounds and the existent conditions of temperature and pressure.
Petroleum Naphtha
- A generic term applied to refined, partly refined, or unrefined petroleum products and liquid products of natural gas, not more than 10 per cent of which distill below 175 °C, and not less than 95 percent of which distill below 240 °C, when subjected to distillation in accordance with ASTM Method D-86.
pH Value - The logarithm of the reciprocal of the hydrogen ion concentration. This indicates the acid or alkaline condition of a substance, pure water and neutral solutions having a pH of 7. Acid solutions have a pH less than 7 ; alkaline solutions, a pH greater than 7.
Polymer - Product of polymerization of normally gaseous olefin hydrocarbons.
Power pump - A reciprocating pump in which the liquid pistons are driven by other means than direct acting steam pistons and rods.
Preheater - Any form of equipment in which heat is applied to a material prior to its introduction into the main heating equipment. The application of heat is usually
Terms Description
accomplished by means of hot fluid which have to be cooled and whose heat would otherwise be wasted.
Pressure Drop - The decrease in pressure due to friction/plugging, which occurs when a liquid or gas passes through a pipe/filter/vessel, etc.
Pressure Vessel
- An enclosed container in which greater than atmospheric pressure is maintained.
Pump Priming - The filling of the liquid end of a pump with liquid to remove vapors present and eliminate the tendency to become vapor lock.
Purging - The displacement of one material with another in process equipment; frequently, displacement of hydrocarbon vapor with steam or inert gas.
Quench - To suddenly cool hot material discharging from a cracking coil, usually by injecting cool oil into the discharge line; its purpose is to check the cracking reaction quickly.
Radiation - The act of emitting energy, particularly rays of light or heat.
Reactor - The vessel in which the major part of a reaction or conversion takes place. In catalytic cracking it is the
Terms Description
enlarged space in which hot oil is converted to simpler compounds.
Reciprocating Pump
- A Positive displacement type of pump consisting of a plunger or a piston moving back and forth within a cylinder. With each stroke of the plunger or piston, a definite volume of liquid is pushed out through the discharge valves.
Reflux - In fractional distillation, that part of the distillate which may be returned to the column to assist in making a better separation into desired fractions is called Reflux. Reflux may be either circulating or induced. Circulating reflux is liquid/vapor which is withdrawn hot, normally cooled, and pumped back to the tower. Induced reflux is liquid formed within a fractionation tower by condensation of vapors by means of an internal cooling coil.
Residue - Heavy oil or bottoms left in the still after gasoline and other relatively low-boiling constituents have been removed.
Rich Oil - The oil drawn off the bottom of an absorber tower containing fractions absorbed from a gas.
Riser - That portion of the bubble plate assembly which PAGE : 21
Terms Description
channels the vapor and causes it to flow downward to escape through the liquid.
Rotary pump - A positive displacement pump used mainly to pump liquids which are either too viscous or too difficult to pick up suctions with a centrifugal pump. There are many types of rotary pump designs, one of the most common being the gear type - in which two gears mesh and rotate toward each other within a very close fitting casing. The liquid is trapped between the gear teeth and the casing and carried around to the discharge side of the pump. The meshing gear teeth prevent the liquid from returning to the suction side.
Rundown Tank - One of the tanks in which product is received from the plant and from which the product is pumped to larger tanks known as storage tanks. Rundown tank is also known as Receiving tank or Day tank, designed to store only one day’s production(with enough cushion) . If the product was received directly into the large storage tanks, the offspec. product due to plant upset would contaminate unnecessarily larger size product storage tank.
Scrubbing - Purifying a gas by washing with water or chemical; less frequently, the removal of entrainment. The equipment used to give intimate contacting of the
Terms Description
material to be purified is called a scrubber.
Separator - A holding vessel used to aid in the separation of light and heavy gravity material. i.e. Separator in reactor section separate liquid and recycle gas.
Simplex pump - A reciprocating pump that has one liquid cylinder on a single drive.
Sour Crude - Crude oil containing an abnormally large amount of sulfur compounds which, upon refining, liberate corrosive sulfur compounds.
Specific Gravity - The ratio of the weight of a volume of a body to the weight of an equal volume of some standard substance. In the case of the liquids and solids, the standard is water. In the case of gases, the standard is hydrogen or air.
Stabilizer - A fractionating tower for removing light hydrocarbons from an oil to reduce vapor pressure; particularly applied to gasoline.
Steam - Water in the vapor state.
Straight Run - Product of distillation of crude petroleum without subjected to cracking.
Terms Description
Stripping - Removal of the lightest fractions from a mixture. The process is usually carried out by passing the hot liquid from a flash drum or tower into a stripping vessel or section (stripper), through which open steam or inert gas is passed to remove the more volatile components of the cut.
Suction Line - Intake line leading from vessel/storage to pump/compressor suction.
Superheated - Water vapor above the saturation temperature at a given pressure.
Surge Drum - A vessel or accumulator which serves as a reservoir for liquid being pumped through a line, thereby overcoming fluctuations in the rate of flow caused by the pump.
Sweet - Having a good odor; pleasant to the sense of smell; negative to the doctor test. i.e. sweet naphtha lean in sulphur content.
Temperature - An arbitrary measurement of the amount of molecular energy of a body, or the degree of heat possessed by it. It should be distinguished from heat itself. Heat is a form of energy; temperature is a measurement of its intensity.
Terms Description
Thermocouple - The junction of two wires of dissimilar metals, which develops an electrical potential that is a function of the temperature; an instrument for measuring temperature by means of the electrical potential produced at a heated junction of two dissimilar metals.
Thermowell - A tube having one end closed, inserted into a vessel pipe, or furnace as protection for a thermocouple or thermometer bulb.
Throttling - To control a flow by operating a valve by hand ,making moves in small increments; such as closing a valve in the steam line of a boiler for controlling the flow of steam to any apparatus.
Treating - The contacting of petroleum products with chemicals to improve the quality.
Turnaround - Time necessary to clean and make repairs on refinery equipment after a normal run. It is the elapsed time between drawing the fires (shutting the unit down) and putting the unit on stream again.
Vapor Pressure - The pressure exerted by the vapors released from any material, at a given temperature, when enclosed in a vapor tight container.
Terms Description
Vessel - A closed container to hold gas and/or liquid under pressure or vacuum. It may be used solely for storage, in which case it is often called a drum, e.g., butane drum, reflux drum, etc. Process vessels will permit volume fluctuations, settling of mixed stocks, demisting of vapors, or reactions (such as treaters or reactors).
Viscosity - The measure of the internal friction or the resistively to flow of a liquid. In measuring viscosity of petroleum products, the values of the viscosity are usually expressed as the number of seconds required for a certain volume of the oil to pass through a standard orifice under specified conditions.
Volatility - The extent to which liquids vaporize; the relative tendency to vaporize.
Water Hammer - The energy or impact developed by the sudden collapse of vapor bubbles.
Weathering - The exposure of crude oils or light oils to the weather, with subsequent evaporation of volatile constituents, resulting in loss; in some cases, oxidation and polymerizing effects are noted also, particularly with cracked and asphalt oils.
Terms Description
Wet steam - Steam containing entrained water droplets.
Wet Gas - A gas containing a relatively high proportion of hydrocarbons which are recoverable as liquids.
1.3 Abbreviation
Item Details
0C Degree Centigrade 0F Degrees Fahrenheit
Amps Amperes
API American Petroleum Institute ASME American Society of Mechanical
Engineers
ASTM American Standard Testing Method
BD Blow Down
BFW Boiler Feed water BPD Barrels per day Btu. British thermal unit
Cat. Catalyst Col. Column Cond. Condensate CS Carbon steel Dept. Department Div. Division EB Ethylbenzene Eng. Engineer
EOR End of run
EP End boiling point (of a distillation)
GC Gas chromotagraph
HC Hydrocarbon
HP High pressure
Kg/cm2.g Pressure Unit
Lab Laboratory
LPG Liquefied Petroleum Gas Maint. Maintenance MP Medium pressure MW Molecular weight MX Metaxylene OX Orthoxylene PARAXYLENE Paraxylene
Item Details ,PX
SAE Society of Automotive Engineers
SOR Start of Run
Supt. Superintendent Xyl. Frac. Xylene Fractionation
PCC Plant Control Center, control room PIB Plant Interface Building
The UOP RECOVERY PLUS system has been designed to improve the recovery of LPG and Reformate from Platforming Process Unit net gas streams.
Increased hydrocarbon liquid recovery translates into improved liquid product yields and, therefore, higher production of more valuable products. Added benefits are improved LPG recovery.
Under the design conditions, the RECOVERY PLUS system improves C5 + yields by 4 LV% and LPG yields by 0.5 LV% based on fresh feed H2 purity of the net gas is increased by 8 mol%.
2.2 Process Flow Description and Controls
RECOVERY PLUS system is composed of a process circuit and a closed loop refrigeration circuit. The process circuit consists of a net gas stream and a slipstream of liquid from the platforming Unit Debutanizer column feed. The refrigeration circuit provides cooling to promote the absorption of LPG and reformate hydrocarbons that would normally exit the Platforming Process Unit in the net gas stream. The net gas & liquid streams are individually cooled & then enter the Absorber, MV-AY233-V01. Vapor & liquid separation occurs through counter current flow. The recovered liquid is sent to the Platforming process Unit’s Debutanizer column for stabilization prior to being sent to storage. The gas stream exits the RECOVERY PLUS system to chloride Treaters (MV-AY231-V04 A/B).
c. Net Gas Circuit d. Liquid Circuit
a) Closed loop Refrigeration circuit
Starting at the Refrigerant Subcooler 233-S06, the propylene refrigerant (liquid) is pressured through LV014 and enters into the receiver / Economiser (233-V03). From the Receiver / Economiser (233-V03), the vapor portion of the refrigerant is sent to a side port of the compressor (233 C01) through a back pressure control valve (PV 038). This ensured there is enough driving force between the 233-V03 and 233-C01 Suction during low load conditions. 233-V03 improves the efficiency of the Refrigeration compressor.
The refrigerant remaining in 233-V03 is pressured to the Combined Vapor-Liquid Chiller (233-S03) via control valve LV002. The chilled liquid refrigerant is maintained 2” below the top of the tubes of the chiller. Frothing of the refrigerant in the chillers covers the rest of the tubes. Process fluids (H2 / HCBN) pass through the tubes of Combined Vapor-Liquid Chiller (233-S03) where they are cooled by evaporation of the refrigerant. The Disengaging drum on Top of the chiller shell allows any entrained liquid to be removed from the vaporized refrigerant.
The vaporized refrigerant leaving the Chiller (233-S03) passes through PV012. PV012 controls the compressor 233-C01 suction pressure during startup only. During normal conditions PV012 is 100% open.
Within the compressor, refrigerant vapor comes in contact with circulating synthetic oil and the compressed gas/oil mixtures discharges from the compressor to the oil separator # 1, 233 V02.
In the oil separator #1 (233-V02), the refrigerant disengaged from the oil and passes overhead though a series of coalescing elements where entrained oil is removed. The oil is recycled to the Compressor. Refrigerant is then sent through oil separator #2 233-V04, where oil is removed to below 10 ppm level. Oil build up in the 233-V04 is sent back into the 233-C01 suction via FO-004. Any entrained oil will settle in the chiller and is recovered in the Oil Reclaimer Circuit.
The refrigerant leaves oil separator #2 & enters the shell side of the condenser 233-S05, where it exchanges heat with cooling water (tube side) & condenses. Condensed refrigerant drains from the condenser (233-S05) in to the tube side of the subcooler, 233-S06. In 233-S06, the condensed refrigerant is cooled further by the Rich oil leaving the liquid Exchangers, 233-S02 A/B. This subcooling allows the compressor capacity to increase without affecting the energy requirements. The subcooled refrigerant is collected in 233-V03 Receiver / Economiser. 233-V03 is designed to hold the total circuit charge at 90% level.
Entrained oil in the refrigerant stream settles in the Combined Vapor-Liquid Chiller (233-S03), where refrigerant boiling occurs. With liquid refrigerant boiling off at - 29 0C the heavier oil settles to bottom of the chiller. The drained oil / refrigerant mixture from 233-S03 goes to Oil Reclaimer (233-Vv07). The oil is reclaimed through a batch process of draining, boiling off the refrigerant and pumping the oil back to the suction of compressor 233-C01. The batch operation is controlled by a logic system.
After compression, a refrigerant / oil mixture is discharged into the oil separator #1 (233 V02). The separation between the oil / gas mixture is achieved in the body of the separator and further separation takes place in coalescing elements positioned inside the separator close to the separator outlet. The bottom of the separator serves as an oil reservoir and is equipped with a level gauge (LG-012) for positive oil level indication. A temperature controlled oil heater (233-Y01) is inserted in the separator to maintain the oil temperature for proper oil viscosity and to minimize oil dilution by the refrigerant during compressor shutdown. Lube Oil is pumped from the V02 by oil pump 233-P02 A/B. The oil then flows through the shell side of the Lube oil coolers (233-S04 A/B) oil passes through a 25 micron element filter 233-F01 A/B before the oil is fed to the bearings, balance piston, shaft seal, compression chamber and compressor slide valve actuator.
c) NET GAS CIRCUIT
The Net gas in (Rich Gas) passes through the tube side of the vapor exchanger (233-S01), where it is cooled by exchanging heat with NET OFF GAS (Lean
Gas shell side). The RICH NET GAS IN then enters the tube side of the 233-S03, where it is further cooled by exchanging heat with refrigerant (shell side). The temperature of the vapor out of the chiller is controlled by TIC-009. As the vapor outlet temp begins to decrease, TV 009 begins to open causing a position of the warm Lean oil to bypass the Liquid Exchangers (233-S02 A/B), and mix with the vapor entering the tube side of the Chiller, causing a change in the heat capacity of the fluid. If the temperature of the Vapor leaving the chiller is too warm, TV 009 will close.
The partially condensed Net Gas, leaving the 233-S03 enters the lower section of Absorber 233-V01. The rich liquid is removed from the bottoms of 233-V01 on LIC-004. The Absorber off gas (NET OFF GAS) is then heated through the shell side of the vapor exchangers 233-S01 & is sent to chloride treaters 231-V04 A/B.
d) LIQUID CIRCUIT
The liquid into the RECOVERY PLUS system is a slipstream from the Debutanizer column feed, and is controlled by FIC-002. This stream is pumped by 233-P01 A/B to the tube side of Liquid Exchanger 233-S02 A /B, where it is cooled by exchanging heat with the Absorber rich liquid (shell side). The lean liquid enters the second tube bundle of the Combined Vapor-Liquid Chiller, 233-S03 and flows to the top of the Absorber. The temperature of the lean liquid entering the absorber is controlled by TIC-011.
As the temperature of the lean oil exiting the chiller, fluctuates, TIC-011 adjusts the compressor capacity control by varying the slide valve position. The rich oil is removed from the bottom of the Absorber, 233-V01 on level control LV-004. The net liquid is heated through the shell side of the subcooler 233-S06, and then flows to the Debutaniser feed Bottoms Exchanger 231-S05 A / B on pressure.
2.3 DCS Description
Distributed Control System for Jamnagar Refinery Complex is of Foxboro I/A series 50 and is capable of plant wide automation.
The architecture of the system will accommodate both functional and geographical distribution of the hardware, software, and database over the plant while allowing system wide access to the distributed data.
The DCS hardware will be state of the art, microprocessor based design, that will be fully tested and reliable. It will permit control and data acquisition functions to be distributed to remote Plant Interface Buildings (PIBs) with operator-consoles located in Plant Control Centre (PCCs).
As stated above all DCS hardware will be in the PIBs, all field inputs will be terminated in the PIBs, all controllers will be in the PIBs and field outputs will be from PIBs only.
Monitoring and Control will be by Operator Console located in the PCC, which in turn is connected to all the PIBs through Fibre Optic Plantwide Control Network.
Foxboro I/A series 50: Following are the main hardware of the system.
WP51B – Operator console with two 19” CRT, Keyboard, trackball and touchscreen.
CP30 & CP40 – Control processor for control and data acquisition. AW51C – Engineering Station for configuration of the system. FBM & FBC – Field I/O card.
The entire operator console will be mounted in two tier consoles in the PCCs.
The hardware distribution and configuration of the Platforming Unit is as under:
For HNUU (221), Platformer (231), CCR (232), Recovery Plus (233) and PSA (234), CP40. FBMs/FBCs will be in PIB 4 and will be linked to Aromatics PCC with Fibre optic cable. PIB 4 is a SCS having two operators console (two CRTs) for start-up and shutdown.
2.3.1 DCS Graphics
Process graphics show process equipment, piping and the instrumentation and control. They closely follow the project PFD’s and P&ID’s. They will be arranged in four hierarchy levels:
Complex (Level 2) Unit (Level 3) Detailed (Level 4)
At each of these levels, the graphics provide the means to move up and down the graphic hierarchy, and also sideways.
The Plantwide Level graphic shows an overview of the whole Reliance Jamnagar Refinery Plant. It displays the main plant areas, their statuses and primary plant data. There shall be no control or process information at this level. The main purpose of this display is for navigation to other displays.
The Complex Level graphics show overview of the Aromatic complex of Reliance Jamnagar Refinery. Only the major flows and other important data specific to each area will be shown. There shall be no process control from this level. Additionally, the Complex Level graphics should indicate when a fault occurs at any point within the process, which will allow the operator to navigate to detailed graphic.
The Platforming Unit Level graphics show most process equipment and major piping and instrumentation. All controllers, important process variables and general monitoring parameters are indicated at this level. ESD trips are also indicated. Facilities are provided for operator actions such as alarm acknowledgement, manipulation of control loops, operation of valves, pumps, etc. Each plant unit is represented by several unit level graphics. The graphics
at this level follow the project PFD’s. Unit Level graphics are intended to be used most of the time for plant operations.
The Detailed Level graphics show all instrument functions implemented in the I/A Series – indicating loops, monitoring functions, equipment statuses, trips, ESD’s, etc. Facilities are provided for alarm acknowledgement; access to all control loops, faceplates, groups and trends. The graphics at this level closely follow the project P&ID’s and indicate almost all P&ID level information. This level of graphics is used to pursue detailed information on the process and the instrumentation.
2.3.2 Graphic Displays
The console subsystem has facility of viewing multiple windows on one screen enabling the operator to conveniently access and control all the necessary factors at the same time.
The graphics shall consist of the following types and overall content: Overview.
Plant graphics.
Group loop displays.
Loop display.
Alarm and event summary
At a minimum, the operator will be able to operate, via touch screen or “track ball” the control strategies i.e., change set points, control modes,
Page linking to more detailed process graphics, as well as alarm summaries will be made from these overviews. The operator can call up directly, any group display covered by the overview screen.
In addition, linking will also be possible to: Group loop display
Loop display
Alarm and event summaries
2.3.3 Group Displays
Important analog measurements grouped according to the process will be implemented as vertical bar graphs. Measurements, such as pressure, temperature etc profiles will give a meaningful operator-overview of the normal/upset status of the plant.
Bar graphs will include operator adjustable ‘set points’ and high/low alarms when measurement deviates from the desired ‘set point’. In this case, ‘Set point’ may include both controller set points and normal operating parameters for indication-only measurements.
The group displays will consist of measurements and statuses presented in vertical bar graph formats. These are often referred to as “face plate” displays, since the vertical bar graphs are arranged in the manner of single-loop controller or indicator faceplates. The grouping is defined on logical grouping of related controllers and indicators within the process unit.
The displays will indicate the following information per group: Loop tag number and description.
Process variable (measurement, set point and output).
Status indication (on, off, run, stop, open, close, etc.).
Alarm status
Mode (auto/manual, remote/local (set point), tracking, etc.).
Units of measurement.
The operator will be able to quickly address any point and make appropriate changes to mode, set point and output and so forth. This display will give the operator direct access to all status and parameters related to one loop, including the ability to change set points, modes of operation and give on/off output commands.
Several of the operator actions will be password (preferred) or key-lock protected, such as:
Changing controller-tuning constants.
Controller configuration data.
Enable/disable of alarms, control actions, changing of alarm settings.
2.3.4 Trend displays
In addition to trending shown on the loop displays, the DCS shall provide the capability of displaying both real time (short-term) and historical trending of process variables with a facility to change the trended variable on the trends display. The trend displays are operator assignable to group in graphical presentation with :
Vertical axis – variable, including measured range/units.
Horizontal axis – time base.
All points shall be available on real-time trend with a minimum sample interval of one (1) second.
2.3.5 Alarm and Event Summary
Either as a standard or a custom display, the DCS will provide a separate tabular listing of alarms and events, which can be called up by the operator with
a single keystroke. Each alarm or event will be listed in order of occurrence and will include a buffer memory so that no alarms are lost.
The alarm and event summary will include:
Date and time.
Tag and service.
Alarm type and priority.
Alarm limit.
Current process variable with Engineering units.
2.4 Design Flow Plan
2.6 Material Balance INPUT Kg/Hr Lean Oil 169953 Net Gas 44578 OUTPUT Kg/Hr Hydrogen rich gas to refinery hydrogen
header
25309
Rich oil to debutaniser Feed/Bottom exchanger at platforming
189222
NOTE: Liquid recovered 19269 Kg/Hr
2.7 Feed and product Specification
Component Kg-mol/h
Gas In Gas Out Liquid
Recovered H2O 0.19 0.114 0.07 H2 4836.2 4814.30 21.90 C1 201.03 186.77 14.26 C2 417.11 263.53 153.58 C3 299.61 79.92 219.67 IC4 34.86 8.12 26.74 NC4 36.50 8.23 28.27 IC5 4.89 0.92 3.98 NC5 5.11 0.84 4.27 PAGE : 46
Component Kg-mol/h
Gas In Gas Out Liquid
Recovered C5OLEFIN 0.34 0.07 0.27 CP 0.15 0.02 0.13 C6+ 9.94 0.77 9.17 Total, Kg/hr 44578.07 25309.19 19268.88 Temperature, 0C 37 28.7 ---Pressure, Kpag 3.601 3.474 ---Molecular Weight 7.63 4.72 43.1 2.8 Chemicals - Details
Chemical Service Required Quantity
Propylene Refrigerant 250ft3 ( 7 m3 ) Specification for propylene product
PROPERTY VALUE MAX / MIN
Propylene, vol.% 99.50min.
Methane plus Ethane, vol. ppm 500max.
Ethylene, vol. ppm 50 max.
C4 & Heavier, vol. ppm 20 max.
Acetylene, vol. ppm 10 max.
Butadiene, vol. ppm 10 max.
Methyl Acetylene
+ Propadiene, vol. ppm 20 max.
Hydrogen, vol. ppm 20 max.
Carbon Monoxide, vol. ppm 5 max. Carbon Dioxide, vol. ppm 5 max.
Oxygen, vol. ppm 10 max.
Ammonia, vol. ppm 12.1 max.
Ammonia, wt. ppm 5.0 max.
Nitrogen (molecular), vol. ppm 30 max.
PROPERTY VALUE MAX / MIN
Water, vol. ppm 10 max.
Green Oil, vol. ppm 1 max.
Carbonyl Sulfur (COS), vol. ppm 1 max.
Arsine, vol. ppm 0.03 max.
Phosphine, vol. ppm 0.03 max.
Propane Balance
2.9 Utility conditions and requirement
2.9.1 Utility Conditions
UTILITY UTILITY BATTERY LIMIT CONDITIONS PRESSURE
(KG/CM2G)
TEMPERATURE ( 0C )
Normal Design Normal Design
Fresh CW Supply 4.5 32 150 Fresh CW Return 2.5 45 150 Desal, Water 3.0 7.0 44 Potable Water 3.0 7.0 44 65 Utility Water 3.0 7.0 44 65 Plant Air 7.0 10 40 65 Instrument Air 7.7 10 40 65 Breathing Air 7.7 10 40 65 Nitrogen 7 10.5 25 65
Fuel Gas Import 3.5 6.5 38 122 Fuel Gas Export 3.9
LPG 3.5 6.5 38 122
2.9.2 Utilities Requirements
Reliance Estimated Utility Consumption
RECOVERY PLUS Electric Power, KW (High Voltage >415V) 3000 Electric Power, KW (Low Voltage =<415V) 30
Cooling Water, m3/hour 520 m3 580 m3 Instrument Air, Nm3 /hour To be determined2 Nitrogen, Nm3/hour None3 Refrigerant (Propylene) 7 m3
Lube Oil, Kg/Annum To be determined2 Reliance Estimated Waste Discharges
RECOVERY PLUS
Vents, Nm3/hour None4
Drains, Kg/hour None3
The above numbers are estimates.
1. The 520 m3 is the estimated cooling water during normal operation with the straight run feed case. The 580 m3 is the estimated cooling water usage during turn-down with the straight run feed.
2. Instrument air and lube oil usage not known at this time.
3. Nitrogen is not required for regular operations. However, nitrogen is required for start-up and shut down. Once the compressor section is finalized, a specification will be provided to determine the amount of nitrogen needed in these instances.
3.0
INTER CONNECTIVITY
General
This section examines the interfaces of the Recovery Plus system with the other processing units of Aromatic Complex.
3.1 Inter Unit Relationship
The Unit obtains its feed from the Platforming unit
Lean oil from Recontact Drum No.1 (MV-231-V02) through pumps MP231-P02 A/B at 21.17KSC & 300 C at Platforming unit to the Recovery Plus Unit.
Net Gas from Recontact drum no.2 MV-231-V03 at Platforming unit to Recovery Plus Unit at 37.13 KSC & 370C
Reach oil goes to Debutaniser Feed-bottoms Exchanger ME231-S05 A/B at 18.6 KSC & 300 C to the Debutaniser MV231-C05 at Platforming unit.
Net Gas (Hydrogen Rich Gas) to chloride Treaters MV-231-V04 A/B at 35.86 KSC & 28.70 C at platforming Unit to Hydrogen Purification system (PSA)
Start up
The Platforming Unit will be started up prior to the Start up of Recovery Plus system.
Once the Platforming unit is on stream, Net Gas can be supplied to Recovery Plus from Recontact drum no.2 231-V03, and Lean oil can be supplied from MV-231-V02 (Recontact drum No.1) through pumps MP231-P02 A/B.
Shutdown
If the Platforming unit shutdowns, then Recovery Plus unit and hence subsequent downstream units i.e. Net Gas chloride treater 231-V04 A/B & Hydrogen Purification system (PSA) will also shutdown respectively.
Normal operations
During normal operations, the Recovery Plus Unit must be operated so that the main objective to recover. LPG and Reformate from Platforming net gas stream is achieved.
3.2 Inter Plant Relationship
General
This section explores the interfaces of the Recovery Plus system with other processing Units in Refinery complex.
Inter Relationship
Propylene, which is used as a liquid refrigerant, will be available from propylene Recovery plant of Fluidized Catalytic cracking complex, once refinery will be started.
Start up
Before attempting to allow any of the above feeds/ products between the Plants, all necessary details with regard to the operating unit must be complete. Additionally, the foreman and the operating units concerned should be notified of the impending startup.
Shutdown
For normal planned shutdowns, each plant will be responsible for notifying the foreman and operating units concerned, of all shutdown operations.
Emergencies between the plants must be recognized and acted upon immediately. Plant operators must aware of steps to be taken in such situations. While some of the emergencies may not result in shutdown, it could cause serious trouble on the units if not properly handled.
3.3 Utility /Off site Relationship
General
This section describes the interfaces of the Recovery Plus Unit with the utility and offsites Areas.
Inter Relationship
The Recovery Plus Unit inter relationship with the following Utilities.
Cooling Water Supply Cooling Water Return
Potable Water Fire Water Plant Air Instrument Air Breathing Air Nitrogen Fuel Gas Start-Up
Before attempting to allow any of the above feeds/ products between the Plants, all necessary details with regard to the operating unit must be complete. Additionally, the foreman and the operating units concerned should be notified of the impending startup.
Shutdown
For normal planned shutdowns, each area will be responsible for notifying the foreman and operating areas/ units concerned, of all shutdown operations.
Emergencies between the plants must be recognized and acted upon immediately. Plant operators must aware of steps to be taken in such situations. While some of the emergencies may not result in shutdown, it could cause serious trouble on the units if not properly handled.
4.0
PREPARING THE UNIT FOR INITIAL START-UP
4.1 Introduction
This phase of the work covers the requirements and activities to be performed prior to commissioning the Platforming Unit.
The objective of the pre-commissioning phase is to:
Verify that the unit and all parts thereof comply with the project specifications, data sheets and design drawings
Ensure that all items and equipment forming part of the unit have been installed correctly and in accordance with the manufacturer’s instructions. Check the integrity of the unit and all parts thereof.
To prepare the equipment for operation by washing, running in, etc. To acquaint the operators with the unit
The pre-commissioning works will encompass general activities as follows:
a) Check that all vendor’s documents for all equipment such as test certificates, inspection certificates and performance test certificates, etc., are available and acceptable.
b) Check that all necessary documentation of the tests carried out during the construction phase including hydrostatic tests, radiographic inspection and any other relevant electrical, mechanical and civil works tests is available and satisfactory.
c) Carry out site checking of all items of the unit and equipment and piping systems as indicated in Inspection Section herein.
d) Prepare a punch list of outstanding items, and assign action parties.
e) Complete and sign all checklists, test reports and log sheets as applicable to the pre-commissioning works. Use applicable standard checklist for monitoring progress and recording of the Contractor’s pre-commissioning works.
f) Ensure that the Reliance/Bechtel/UOP representative witness all check lists, test reports and log sheets as required.
g) Procedures for storing pre-commissioning documentation shall be provided by the Contractor and approved by RPL in order to establish a clear audit trail for all pre-commissioning activities.
h) Complete all punch list items which affect the safety and operability of the unit.
4.2 Utility system readiness:
4.2.1 Piping Network
Please refer interconnectivity P and I. D. of Platformer Unit for Utility distribution and network
4.2.2 Commissioning of Utilities
For ease of operation, the utility systems such as water, air, N2, firewater, etc. should be put in operation as soon as construction schedule allows. Fuel Gas, Flare, etc. should be prepared but not to be commissioned until process units are ready for hydrocarbon entry.
Fresh Cooling water supply/return Desalinated/Potable/Utility/Fire water Plant /Instrument/Breathing Air
Nitrogen
Fuel Gas Import/Fuel Gas Export/LPG
Flare/Blowdown system, aromatic closed drain Other system i.e. Feed, Product, Chemical, etc. Communication System
Fire detection/protection and gas detection system
Cooling Water system:
After mechanical completion of CW Supply/Return system, ensure flushing / testing of each system. Ensure that all-utility valves at equipment / service stations are closed. Charge the header up to battery limit and then charge header/ sub header in Plot.
Water system (Desalination Water / Potable Water / Utility water / Fire Water)
After mech. Completion of various water system, ensure through flushing /testing of each system. Ensure that all utility valves at equipment / service stations are closed. Change the header up to battery limit and then charge header / sub-header in Plot.
Air system (Plant Air/ Instrument Air/ Breathing Air)
After pneumatic test, system should be blown with air. These systems should be as dry as possible. Instrument air system to be dried with instrument air and after checking dew point (-40 0C) at various points, system can be charged. Ensure that all utility valves at equipment/service stations are closed. Carry out tightness test /leak test at service pressure, check and rectify leaks.
Nitrogen system
Carryout the blowing and flushing operation of the Nitrogen system with air. Carryout the tightness / leak test with air. Once system became leak free, air free the system with N2 purging. Ensure that the nitrogen system oxygen content is within limit prior to charging of header/ sub-header with N2. Ensure that all utility valves at service stations are closed and connections to all equipment are blinded.
Caution: Nitrogen is an asphxyant gas and is both odourless and colourless. Installation causes rapid unconsciousness by blocking of the oxygen supply followed by death within a short time.
Fuel Gas Import / Fuel Gas Export / LPG
Carryout the blowing and flushing operation of the above system with air. Carryout the tightness / leak test with air. Ensure that all utility valves at equipment are closed. Once system became leak free, air free the system with
N2 purging. Ensure that the system oxygen content is within limit (< 0.2%) prior to charging of header / sub-header wit FG/LPG.
Flare / blow down system, Aromatic closed drain
Carryout the thorough blowing and flushing operation of the above system with air. Carryout the tightness / leak test with air. Ensure that all utility valves at equipment are closed. Once system became leak free, air free the system with N2 purging. Keep the system under positive pressure of N2 and monitor. Ensure that the system oxygen content is within limit prior to charging of header/ sub header with Hydrocarbon. Keep flare header under positive flow of N2 still purge FG is available (the jobs are pertaining to the offsites).
Other system
All feed, product, chemical, etc. piping to / from battery limit and storage facility thoroughly flushed, blown, leak tested, dried and air free prior to charging hydrocarbon.
Communication system
Ensure that Public address system/ Walkie talkie/ Pagers / Telephone system etc. as per project specification and drawings are installed in plant. System must be functional checked and performing as required. A clear, loud and uninterrupted communication link between field and Control room / Maintenance / Utility block / Laboratory / offsite, etc. must be established.
Fire Detection/ Protection system and Gas Detection System
Fire and gas detection system as per project specification and drawings are installed in plant. System must be functionally checked and performing as required. Energise the system and make it functional prior to commissioning of unit. Ensure that fire protection system and potable fire extinguishers are installed at specified place, prior to entry of Hydrocarbon in process/ utility system.
4.3 Inspection of Equipment
General Checks
For most of above items, general checks are required and can be carried out as follows: Refer UOP/ Bechtel data sheet and compare against vendors’ data sheet and actual equipment at site.
A. Specifications check for
a. Pressure, Temperature and vacuum, flow ratings, Capacity, surface area, etc., b. Material of construction, thickness and corrosion allowance
c. Head, capacity, speed, NPSH requirement, type, seals, bearings, number of stages, lubrication and cooling systems, etc.
d. Type of driver, its power ratings, etc.
e. Nozzle sizes and orientation, flange rating, type and finish f. Type of lining, thickness and material
g. Stress relieving and / or heat treatment h. Foundation design for full water weight
B. Confirm that the equipment is hydrotested and date / time/ witness by, etc. are recorded (wherever it is applicable and agreed upon). In case of rotary equipment ensure the test run carried out at shop and results are available. C. Verify that all code plate information are correct
D. Material test certificates are available
4.3.1 Piping and Supports
The unit must be constructed in accordance with the Bechtel P & ID and Isometrics. The note, elevations, dimensions, etc. must be correct. One should be able to start and shutdown the unit as per suggested procedure. Piping for special procedure like dryout special material preparation as well as alternate flow schemes must be incorporated into the system. If the unit is connected to other process facilities adequate means must be provided to receive feed and send products to various facilities without contaminating any stream with another streams. To check and ensure that adequate means for measuring flow temperature pressure and sampling as well as is available.
4.3.1.1 Visual Inspection
Line by line visual inspection of the complete piping system and associated parts there of to ascertain completeness against P and I D drawings and accepted practice for installed piping systems.
a. Verify that all quality control inspection requirements (X-rays, stress relieving, etc.) have been fulfilled.
b. Check that piping system has been pressure tested in accordance with the code governing their design and approved by Reliance.
c. Check that piping system have been properly flushed / blown as required. d. Check that piping system has been properly supported. Pipe hangers/ supports
are allowed expansion in proper direction.
e. Check that drains in the process / utility lines are at the lowest points.
f. Check that spectacles are in their correct position as identified on the P & ID drawings.
g. Check that insulating joints are proper at interface & electrical continuity / bonding is proper.
h. Check that lines are connected to the correct nozzles of the equipment. i. Check for desired flange ratings, bolts & gaskets specifications.
j. Check and inspect that all flanges are properly aligned and tightened.
k. Check that all temporary strainers are presently fitted in the required positions l. Check that all inline instruments are correctly mounted
m. Check that all instruments connections are proper n. Check insulation and colour code as specified
o. Check that piping routing is proper and all valves are accessible without any hindrance for movement
4.3.1.2 Hydrostatic Test
The piping system will be pressure tested to prove the pressure integrity of the main components (pipe, valves, flanges, gaskets) of the system. The test shall be performed in accordance with Standard Construction specification, supplemented by the Contractor’s standard hydrostatic test procedure
approved by RPL. For test purposes, the piping system has been divided into a series in Document “Line Designation Table”.
All the piping systems will be hydrostatically tested except specific system where hydraulic fluids are not allowed due to operation reasons. Those systems will be subject to pneumatic testing.
A pressure test report will be completed for each test loop for record purposes using Reliance Standard Form. All untested joints shall be clearly shown on the hydrotest diagrams.
SAFETY NOTE: Hydrostatic testing is carried out to prove the pressure
integrity of the piping system under test. Accidents, sometimes fatal, have been recorded during such testing. Manning levels in areas where hydrostatic testing is to be performed should be kept to a minimum. All personnel engaged in the test should be fully briefed and all precautions taken in respect of personnel safety. Danger signs and notices should be erected at all strategic locations. Piping routed outside of the main plant boundary should be cordoned off and manned to prevent accidental access by unauthorised or third party personnel. All safety equipment shall be on site for the duration of testing. All personnel directly or indirectly engaged during the test shall be equipped with personnel protective and safety equipment.
Important Checks and Guidelines
a. On line instruments and instrument impulse lines will be temporarily removed and / or disconnected before testing.
b. Check that hydrotest pump, valve, fittings, pressure gauge are in good working order. Filling line/ test equipment shall be connected at lowest possible point to avoid entrapment of air in the system while filling.
c. Check that all test gauges are available with relevant latest test certificates, with direct reading gauge and suitable range so that test pressure readable in 40-60% range. The test gauge shall be mounted at lowest point to account liquid head of system.
d. Check that all in-line valves are in fully open position.
e. Check that all safety equipment like cordoning rope, sign board, etc. are available at testing site and placed at strategic location.
f. Check that check valves are removed from the line or its internal removed, if required.
g. All welds shall be free of slag, grease, oil, paint and any other foreign materials, which prevent proper examination.
h. Vents to be provided on test fittings if it is not provided on the line i. Blinds used shall be in accordance with Pipe Line Class
j. There are sufficient numbers of vents/ drains located in suitable position. While filling the piping, ensure that all air is vented at highest point and system is full of test fluid.
k. Vessel and water temperature should be always above 15 0C to eliminate the possibility of cold fracturing of the metal.
l. Hydrotest pressure should be as per LDT (line designation table) or as per piping class & should not be higher than lowest rated component of system. ANSI B 31.3 must be followed while testing piping system.
m. The weld joints, flange connections and the sections of greatest strain (the areas close to opening and those where two different types of materials are
connected) must be checked visually. The test is acceptable if no loses, sweating or fall of pressure are detected for the time of test.
n. Test pressure will be held for sufficient time to visually determine if there are any leaks, but not less than 2 hours.
o. Drain out the water from the section after the hydrotest is completed.
Note:
Ensure that under no circumstances the pressure applied does not exceed the allowable test pressure of the lowest rated component in the loop.
Keep the vents open to prevent from pulling a vacuum and possibly collapsing equipment, while draining the system after hydrotest.
Ensure that, chloride content of the treated water used for hydrotest of the section that contains austenitic steel is below 50-ppm wt%. If this is not possible then the test water should have a max. of 0.5 wt% sodium nitrate / specific chemical added to it. Such system should be drained and dried after hydrotest as soon as possible.
4.3.1.3 Flushing
The piping system will be flushed in order to remove construction debris, accumulated corrosion products and scale to prevent blockages and damage to equipment during actual start-up
Prior to commencing the flushing operation, the contractor will divide the piping system into a series of flushing loops. Configuration of flushing loop mostly remains as hydrotest loop. The loops will be presented in diagrammatic form, as a markup to the plant P & Ids using local site knowledge and the guidelines
