Internship Report

Internship Report | 2014

THIRD YEAR INTERNSHIP AS A METALLURGICAL ENGINEEROFFERED BY

NED UNIVERSITY OF ENGINEERING AND TECHNOLOGY DEPARTMENT OF METALLURGICAL ENGINEERING

SYED MUHAMMAD SHAHBAZ(MY-014)syedshaz1992@gmail.comCONTACT #: +92 345 3250881

INTERNSHIP SUPERVISOR: Mrs. ASIFA TASNEEMDURATION OF INTERNSHIP: June 2nd to June 27th, 2014DATE OF SUBMISSION: June 27th, 2014

ACKNOWLEDGEMENT

Any accomplishment requires the effort of many people and there are no exceptions. The report being submitted today is a result of collective effort. Although the report has been solely prepared by me with the purpose of fulfilling the requirements of the course of BE. Metallurgy (Bachelor of Metallurgical Engineering), there are innumerous helping hands behind it who have guided me on my way.First of all I would like to thank Almighty Allah for this great opportunity granted to me to practically understand and practice what I have studied.Secondly, I would like to appreciate the role of my group advisors: Mrs. ASIFA TASNEEM Mr. ZUBAIR Mr. SAJJAD HUSSAIN Mr. AMAAN ULLAH DAHI Mr. FAZAL Mr. MUDASSIR KHALIL Mrs. AMMARAH MOIN

for all the directions and guidelines on every stage of work regarding the problems and counter measures, which were arisen during the work and most importantly the management of the team, priority goals and critical tasks which should be dealt tactfully.

Finally, yet importantly, I would like to express my heartfelt thanks to my Beloved parents for their blessings, my friends/classmates for their Wishes towards the successful completion of this internship.

PREFACE

Over the summer of 2009, I was granted the unique opportunity to be employed by T UWAIRQI Steel Mills as an Internee. Under the supervision of TUWAIRQI ENGINEERING department, I was lucky enough to undertake 26 days internship that expanded my horizons and my way of thinking.

TUWAIRQI Steel Mills is a project of Al-TUWAIRQI Group of Saudi Arabia. It is being set up over an area of 220 acres at Bin Qasim, Karachi with a production capacity of one million tons. The capacity can be expanded to three million tons. The mills will start functioning soon.

My main project was based within the TUWAIRQI ENGINEERING discipline and primarily involved practical understanding basic theories under the supervision of concerned Engineers.

INDEXS. No.TopicsPage No.

01Introduction04

02Internship and Objective05

03About TSML Engineering05

04AssignmentI. MIDREX ProcessII. Process Flow DiagramIII. Reformer And its AdvantagesIV. Chemistry Of ReformerV. Consumption per ton of DRIVI. Backward And Forward Integration

06

05Study About Valve10

06Plant layout diagrams11

07Problems About pressure Drop11

08Spread Sheets project11

09AutoCAD11

10MIDREX Plant12

11Iron Oxide Storage And Handling14

12DRI Products17

13Water Complex18

14Cooling Tower19

15Work Experience At TSML Engineering20

Introduction:

The Al-TUWAIRQI Group of Companies {ATG} one of the leading business concerns in the Kingdom of Saudi Arabia and the largest private sector steel producer, is in the process of setting up a steel making plant in Karachi Pakistan. The project namely TUWAIRQI Steel Mills Limited (TSML), Whose foundation stone was laid by the president of Pakistan General Pervez Musharraf on the30thof March, 2006, spreads over 220 acres and has a strategic location at Port Qasim Karachi.TSML shall be a state-of the-art steel making complex becoming the biggest steel producing project in Pakistan. The plant shall have a capacity of 1.28million tons per annum using the worlds most advanced DRI {direct reduced iron} technology of the MIDREX process which uses natural gas to convert iron ore into Direct Reduced Iron. The process uses both lump iron ore and iron pellets as the raw material and recycles the used gas. The process lowers both energy consumption and environmental impact, making it an environmentally friendly process. Along with an Intermediary Phase which includes the setting up of an Induction Furnace to produce 0.5 million tons of billets per annum is also being executed. The Intermediary Phase will be completed close to the completion of DRI Plant. Phase II of the project consists of installation of an Electric Arc Furnace and continuous caster to produce 1.28 million tons high quality billets.

INTERNSHIP:An internship is a work-related learning experience for individuals who wish to develop hands on work experience in a certain occupational field. Most internships are temporary assignments that last approximately few weeks to an year.

OBJECTIVE:To develop skills and techniques which are directly applicable to my career. ABOUT TSML ENGINEERING:TSML Engineering Services is a wholly owned subsidiary of TUWAIRQI Steel Mills Limited, which is an affiliate of Al-TUWAIRQI Holding, a prestigious Saudi Arabian Group of Companies, globally involved in a number of technology intensive businesses including steel manufacturing, fabrication services and engineering design services to the industrial sector.To provide competitive engineering solutions and technical services to its business users at the lowest consistent rates with fair compensation to the Team Members, safety for public, reasonable protection of environment and development of technology to provide remarkable services for customers.

ASSIGNMENT

MIDREX Process Overview:

IRON ORE REDUCTION:

Iron ore consist primarily of iron oxide (Fe3O4), a combination of iron and oxygen. The basic function of all iron ore reduction technologies is to economically remove the oxygen from the iron ore and leave only the iron. If the iron ore reduction technology operates entirely in the solid state, then the product is called DIRECT REDUCED IRON, or DRI.

To produce DRI, the oxygen in the iron oxide is chemically removed by reacting with CO and H2at very high temperatures of about 900c.

Within the MIDREX plant, the main unit operation is the MIDREX shaft furnace. Inside the MIDREX Shaft furnace, the iron ore is converted to DRI. The spent reducing gases exit the top of the shaft furnace where they are cleaned and cooled. The recycled process gas contain a mix of CO2 and H2O unreacted H2 and CO, and inert N2 circulating in the system. To obtain a high enough gas quality to reuse in the shaft furnace, most of the CO2 is removed from the recycled process gas via a vacuum pressure swing absorption (VPSA) unit. After this step, the process gas is mix with the fresh synthesis gas. St this point, the gas is near ambient temperature. Therefore, the gas must be heated to about 900 C prior to entering the shaft furnace, to ensure maximize reduction efficiency.PROCESS FLOW DIAGRAM

REFORMER:The primary raw material source to produce the reducing gas for the reactor is natural gas . Natural gas is reacted with CO2 and water vapors across a proprietary catalyst to produce a reducing gas rich in CO and H2.

ADVANTAGES OF MIDREX REFORMER: Environmental advantages such as producing less dust particles & generating less noise pollution. Technical advantages such as Higher quality products in terms of carbon content flexibility and high degree of metallization Much more energy efficient

CHEMISTRY OF REFORMER:

REACTION:CH4 + H2O CO + 3H2CH4 + (3/2) O2CO + 2H2OCO + H2OCO2 + H2

CONSUMPTION PER TONN OF DRI:

Electricity400 kWh/TLs

Electrodes1.2 kg/TLS

Oxygen35 Nm3/TLS

Gas5 Nm3/TLS

Charge Coal10 kg/TLS

Coal Powder (Foamy Slag)7 kg/TLS

Lime40 kg/TLS

Backward Integration:

Forward Integration:

STUDY ABOUT VALVE: Two Types of Valves ON/OFF Flow Control Gate Valve Ball Valve Globe Valve Butterfly Valve Check Valve Pinch Valve

PLANT LAYOUT DIAGRAMS: Process Flow Diagram Piping & Instrumentation Diagram

PROBLEMS ABOUT PRESSURE DROPS: Line Sizing Criteria For Liquid Lines Line Sizing Criteria For Gas Lines

SPREAD SHEETS PROJECTS: Unit Conversions

AUTOCAD: Basic concept of AutoCAD about 2-D and 3-D.

MIDREX PLANT:Within the MIDREX plant, the main unit operation is the MIDREX shaft furnace. Inside the MIDREX Shaft furnace, the iron ore is converted to DRI. The spent reducing gases exit the top of the shaft furnace where they are cleaned and cooled. The recycled process gas contain a mix of CO2 and H2O unreacted H2 and CO, and inert N2 circulating in the system. To obtain a high enough gas quality to reuse in the shaft furnace, most of the CO2 is removed from the recycled process gas via a vacuum pressure swing absorption (VPSA) unit. After this step, the process gas is mix with the fresh synthesis gas. St this point, the gas is near ambient temperature. Therefore, the gas must be heated to about 900 C prior to entering the shaft furnace, to ensure maximize reduction efficiency.

MIDREX Process Overview

IRON ORE REDUCTION:

Iron ore consist primarily of iron oxide (Fe3O4), a combination of iron and oxygen. The basic function of all iron ore reduction technologies is to economically remove the oxygen from the iron ore and leave only the iron. If the iron ore reduction technology operates entirely in the solid state, then the product is called DIRECT REDUCED IRON, or DRI.

To produce DRI, the oxygen in the iron oxide is chemically removed by reacting with CO and H2at very high temperatures of about 900c.

REACTION:Fe2O3 + 3CO2Fe + 3CO2Fe2O3 + 3H22Fe + 3H2O

REFORMER:The primary raw material source to produce the reducing gas for the reactor is natural gas . Natural gas is reacted with CO2 and water vapors across a proprietary catalyst to produce a reducing gas rich in CO and H2.

REACTION:CH4 + 2O2 CO2 + 2H2O

BLOCK DIAGRAM:Top Gas Fuel

IRON OXIDE STORAGE AND HANDLING:Pellets are delivered in the surge bin at the port. After weighing, a conveyor transports the pallets to the pallet pile. The pallet pile is equipped with a stacker and will maintain a sufficient supply operation. The pallets are weighed and transferred to the oxide day bins. The day bin acts as a buffer of prepared oxide that is fed to the shaft furnace.The day bin then discharge to a screening operation to separate the off specification fractions from the desired 6-20 mm oxide fractions. The desired oxide fractions are discharge on the oxide transfer conveyor. Unusable material is discarded.

The material on the oxide transfer conveyor is weighed and discharged onto the furnace feed conveyor.

PRODUCT MATERIAL HANDLING:The material is transferred from the briquette cooling conveyors to the HBI conveyors, which are equipped with product scales. The HBI product is transported to the product screening station 1 where it is separated into product fines (0-6.35 mm) and HBI (6.35-120 mm). The fines are fed into the ground floor product fine bunker, while the HBI is weighted and transported on the product collection conveyor to the stacker conveyor for storage. The HBI product storage has a capacity of 100,000 tons per pile.The HBI is reclaimed from the HBI product storage and transported via conveyor to the product screening station 2, where it is screened. The HBI is transported via conveyor to the port.All process operation within the product material handling system are routed to various bag houses for the control of particulate emissions. The storage pile and associated operations are controlled with fugitive suppressants.Process Gas System:Spent reducing gas (top gas) exits the reduction zone of the reactor through the refractory lined top gas duct and enters the top gas scrubber to be cleaned and cooled. Inside the top gas scrubber, the gas passes through two distinct processing zones.

First the gas flows through the venturi portion of the scrubber where it is rapidly cooled and the particulate matter is wetted and removed. Then the warm gas is split into two streams that pass through two parallel packed beds (for additional cooling) and two sets of spin vanes (to remove water droplets) within the scrubber. After scrubbing and cooling, approximately two-thirds of the clean top gas (now called process gas) flows through a second set of mist eliminators and then to the inlet of the first stage process gas compressor, followed by a second compressor. These compressors are centrifugal type machines designated as first stage and second stage process gas compressors. After compression, the process gas is mixed with natural gas and preheated to form the feed gas for the reformer. The other one-third of the cleaned top gas (now called top gas fuel) is mixed with a small amount of natural gas and then passed through a mist eliminator to remove water droplets before fueling the reformer main burners. It is important to note that the Top Gas Scrubber is not a control device but a process device. The process gas system does not vent directly to the atmosphere during regular operation.

Heat Recovery System:The reformer flue gas exits on both sides of the reformer and enters the parallel train heat recovery system. Each parallel system contains combustion pre heaters and feed gas pre-heaters, all of which consist of alloy bundle type heat exchangers suspended in the refractory lined heat recovery ducts.The combustion air pre-heaters are designed to preheat the combustion air to about 600 C in two stages. The feed gas pre-heaters located downstream of the combustion air pre-heater heat the feed gas to approximately 600 C as well.The flue gas exits the parallel trains through a common ejector stack which generates the required draft with a single ejector stack fan. The ejector stack is an induced draft (venturi type) flue gas stack. It uses the ejector stack fan to generate sufficient suction to pull the flue gases out of the reformer and through the heat recovery system. The heat recovery system increases the reformer capacity and reduces the net plant energy consumption by approximately 25-30%.

DRI Products:The MIDREXProcess can produce three different product forms, depending on the application: cold DRI (CDRI), hot briquetted iron (HBI) and hot DRI (HDRI).

CDRI is generally stored for later use in a nearby electric arc furnace (EAF). HBI is a briquetted product that is ideal for storage and for shipping to distant consumers. HDRI is discharged hot from the shaft furnace and transported to an EAF for melting.CDRIMost MIDREXPlants built to-date produce CDRI. After reduction, the pellets and lump are cooled in the lower part of the MIDREXShaft Furnace to about 50 C. This material is temporarily stored in silos to passivate it before transportation to an adjacent EAF or another site. CDRI is ideal for continuous charging to the EAF.HBI and Hot Briquetting:Hot briquetting of DRI has been practiced on an industrial scale for more than three decades and is now the preferred method of preparing DRI for storage and transport internationally. To make HBI, hot DRI is discharged from the MIDREXShaft Furnace at about 700 C and compressed into pillow-shaped briquettes with a typical size of 30 x 50 x 110 mm. HBI is 50 percent denser than DRI pellets and lump, which reduces the tendency for re-oxidation.This enables HBI to be stored and handled without special precautions as recognized by the International Maritime Organization (IMO). HBI can be moved using typical scrap handling equipment and easily batch charged to the EAF, thus requiring no capital investment by the steel mill. HBI can be continuously charged with specially-designed systems.

HDRICharging of HDRI to an adjacent EAF at 600 C or higher provides the optimum way for DRI users to increase productivity and reduce cost. MIDREX offers three methods for hot transport: HOTLINK, hot transport conveyor and hot transport vessels.Water Complex:

Clarifier Hot sump Warm sump Machining and Cooling Water Pump Cooling Tower Cold Sump

Pumps: Heat Exchanger Pumps Cold Process Water Pumps Hot Water Pumps Cooling Water Recirculation Pumps

Tanks: Hot Water Tank Warm Water Tank Machining and Cooling Water Tank

PROCESS WATER FLOW:The process water is key because it is used in scrubbers and for providing seal in case of damaging the pneumatic seal. The seal gas if fail to restrict the toxic gases then process water will keep toxic gases intact and do not allow them to escape into the atmosphere.

Clarifier:The tank is used for the collection of water after it is used by the process, the basic function of clarifier is to separate the dust particles by the action of centrifugal force due to which heavier particles move to center with the help of vipers.

HOT SUMP:The hot Sump is a tank which store water after the overflow of clarifier. This hot water is used in dust collector and in scrubber in order to maintain the temperature to an extent. WARM SUMP:The warm sump stores the water to increase the temperature of water to limit which is also used to in some parts of the plant.MACHINING AND COOLING SUMP (MCW):The MCW is used for cooling. MCW is used for cooling of plant and instrument air compressors and to avoid corrosion.

COOLING TOWER:The water from hot tank after completing its requirements is sent to cooling tower. There are 5 cooling towers out of which 4 are running and 1 on standby. The water is pulled to the top of tower by high pressure motors and introduced into the tower. The hot water flow down and exchanging heat as a result water losses heat and air gains heat and remove from the top by action of induced draft.

WORK EXPERIENCE AT TSML ENGINEERING: Being undergraduate student, it was a great opportunity for me to work as internee with professionals in one of the reputed consulting firm of Pakistan. The attitude, behavior, knowledge and the training methods adopted by these professionals helped us a lot to increase my professional and personal growth. It was a great learning experience, my vision has enlarged drastically. My approach toward the practical work has changed a lot. It has been a very useful experience; getting such exposure to practical work during this phase will help us immensely while choosing my appropriate field.

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