タイトルまたは説明
About Induction Melting
Furnace
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Induction Melting Furnace is major steel producing technology using
scrap & sponge iron (directly reduced iron) as main raw
material. This technology contributes significant steelmaking
capacity in secondary steel sector in India and abroad. It has
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Some distinct advantages:
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1. Low project capital cost
2. Low energy cost
3. Consumes steel scrap which is a major solid waste
4. Environment Friendly, as it produces lower emission than primary
blast furnace
5. Uses clean fuel i.e. electrical power
6. Can be set up near source which saves transportation cost of raw
material as well as finished goods.
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Manufacturing Process
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Induction Furnace Process includes melting of various types of
steel scrap in a pot. The energy required for the melting process
is provided by electrical induction. The feeding of raw material in
the induction furnace is on intermittent basis. As one charge of
scrap melts, slag is removed from the molten metal and certain
alloys are added to achieve the desired grade of steel. Molten
metal is then poured into refractory lined buckets from where it is
further poured in different sizes Moulds to get the desired size of
steel cast. Ingot/Billet is allowed to cool down and then the
product is separated from the Moulds.
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Flue gases are generated during melting of scrap. The
characteristics and volume of these gases mainly depends upon type
of scrap used in the furnace, i.e. with the degree of contamination
in the scrap. These flue gases need proper treatment for removal of
dust particles/gases before being discharged into the
atmosphere.
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Air Pollution
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Steel scrap comes from various sources and generally has
contaminants/coating etc on it. When this scrap is heated
contamination/coating etc. disintegrates from steel and comes out
either as slag or becomes air borne, thus causing air pollution.
The major source of Air Pollution is :
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1. Dust & Dirt
2. Rust
3. Oil & Grease
4. Paint & Galvanized Iron
5. PVC Coated Steel
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Capacity Calculation of required Equipment for Air
Pollution Control Device:
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The volumetric capacity of Air Pollution cannot be judged as such,
but fair engineering estimation can be made with data
like:
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1. Furnace Capacity
2. Power Rating in KWH
3. Detailed Dimensions of Furnace
4. Air Cooler Arrangement for workers at Furnace Platform
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Characteristics of Air Pollution Generated In Induction
Furnace:
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1. Pollutants: Dust & Dirt, Metal Oxide & Traces of NO, SO
, CO, CO x 2 2
2. Concentration: Average ******0 mg/Nm , Max. ********0 mg/Nm
3
3. Temperature: At Hood: ******0 C, At Bag House : *****0 C
4. Nature of Dust: Non Sticky, Non Abrasive and Non Explosive
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Control Practices
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The control practice adopted in controlling air pollution in this
industry mainly depends upon following parameters:
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1. Dust/Gas Concentration at inlet
2. Discharge Standards
3. Temperature of Flue Gases
4. Nature of Pollutant i.e. Dust (Particulate) or Gaseous
5. Nature of Dust i.e. Sticky, Abrasive
6. Nature of Gases i.e. Corrosive, Non Corrosive
7. Control Practices
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Selection of Technology for Air Pollution Control
Device
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The following technologies are usually adopted for Air Pollution
Control System in Induction Furnace industry:
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a. Bag Filter Type System (Dry)
b. Venturi Scrubber Type System (Wet)
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About Bag Filter Type System (Dry Process)
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Working of Equipment Bag Filter Type System
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1. Suction Hood
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Feeding of raw material is an intermittent process in Induction
Furnace and at the time of completion of every heat, molten metal
is tapped with tilting platform of furnace. Hence, it requires a
Movable Hood System so as to facilitate slag removal, raw material
(bulk) feeding and tilting of platform. Hoods are designed based on
crucible diameter and optimum clearance of hood from furnace.
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2. Spark Arrestor:
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This is a pre-filtration device. It is used for arresting live
particles and medium to large hot particles which can damage &
burn bags. Depending upon factors such as Flue Gas Volume, Dust
Load & Temperature Profile, this can be a
Gravity Chamber or Cyclone (with multiple tubes). The Spark
Arrestor, depending upon actual conditions in any particular unit,
can thus be designed based on centrifugal or gravitational forces
or combination of both, suitable for that particular unit.
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3. Bag Filtration System :
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It is used for fine filtration of Flue gases to remove dust
particulate matter. Dust particles are retained on one side of Bags
and clean gases are received on other side. The combined treated
gases from all the bags are collected at top of bag house and are
passed through to ID Fan. The dust collected on other side of bags
is de-dusted through pulse air jet mechanism with high pressure
air. The dust is collected at bottom of hopper and is discharged
through a Screw Conveyor and Rotary Air Lock Valve. Pulse jet
mechanism is carried out through high pressure air with the help of
sequencer and solenoid valve.
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4. ID Fan:
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ID Fan provides necessary driving force to convey flue gases from
suction hood to top of the chimney. The volume sucked overcomes the
total resistance offered by equipment and duct with the help of
fluid horse power provided by ID Fan driven by suitable motor.
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5. Stack (Chimney):
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The generated gases are passed through chimney of suitable height
and diameter. The chimneys are provided and based on volume of flue
gases, temperature, dispersion desired, composition of gases and
legal provisions for height.
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Advantages & Disadvantages of Bag Filter Type
System
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Advantages:
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1. Low Power Consumption
2. Dry System, No water pollution
3. No corrosion of metal except normal wear & tear
4. Suitable for dust pollution which are the major cause of
pollution in induction furnace
5. Achieves desired characteristic of treated gases even for high
dust load, as
   Efficiency of bag filters is very high
6. Low operation & maintenance cost
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Control Practices
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1 Large Floor Area
2 Unchecked high temperature can lead to burning of bags.
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About Venturi Scrubber Type System (Wet
Process)
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Working of Equipment Venturi Scrubber Type
System
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1. Suction Hood:
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Feeding of raw material is an intermittent process in Induction
Furnace and at the time of completion of every heat, molten metal
is tapped with tilting platform of furnace. Hence, it requires a
Movable Hood System so as to facilitate slag removal, raw material
(bulk) feeding and tilting of platform. Hoods are designed based on
crucible diameter and optimum clearance of hood from furnace.
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2. Ducts & Bends:
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Ducts and Bends are required to convey flue gases from point of
suction to the chimney and connect various equipments like Hood,
Venturi Scrubber, ID Fan and Chimney. Their sizes are based on flue
gases volume & temperature.
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3. Venturi Scrubber:
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In Venturi Scrubber the flue gases are passed through a converging
section where velocity of the gases becomes very high. The water is
sprayed on high velocity gases with high pressure at throat. The
particles in the gases become wet. The purpose of throat is to
provide the area with highest velocity and wet these particles so
that they become heavy and easily removable. The gases are then
passed through a diverging section where lot of energy is recovered
which was lost in converging section. These gases are then passed
through separator where wet dust particles are collected at bottom
and clean gases are passed through mist eliminator followed by exit
from scrubber.
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4. ID Fan :
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ID Fan provides necessary driving force to convey flue gases from
suction hood to top of the chimney. The volume sucked overcomes the
total resistance offered by equipment and duct with the help of
fluid horse power provided by ID Fan driven by suitable motor.
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5. Stack (Chimney) :
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The generated gases are passed through chimney of suitable height
and diameter. The chimneys are provided and based on volume of flue
gases, temperature, dispersion desired, composition of gases and
legal provisions for height.
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Advantages & Disadvantages of Venturi Scrubber Type
System
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Advantages :
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1 Low Floor Area
2 Can handle high temperature gases
3 Suitable for gas pollution such as SO , NO , etc. 2 x
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Disadvantages :
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1 Higher Power Consumption to achieve desired standards
2 Generates Water Pollution
3 Material of Construction is prone to corrosion hence low life
cycle
4 Choking of pipe, Nozzle and duct (near scrubber) due to Wet
condition
5 Higher operation & maintenance cost
6 Can remove submicron particle only with very high pressure drop
leading to still higher power consumption
7 Material of Construction is prone to corrosion hence low life
cycle
8 Choking of pipe, Nozzle and duct (near scrubber) due to Wet
condition
9 Higher operation & maintenance cost
*0 Can remove submicron particle only with very high pressure drop
leading to still higher power consumption
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Discharge Characteristics as Per Norms
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1. Dust : Less than **0 mg/ Nm3
2. Ÿ Temp : Less than *****0 C
3. Gases : Traces of SO , NO , Co , Co 2 x 2
4. Suction Efficiency : More than *0%
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国: |
India |
モデル番号: |
APCDIF1
|
离岸价格: |
( Negotiable ) (交渉可能)
Get Latest Price
|
ロケーション: |
India |
最低注文量の価格: |
- |
最低注文量: |
1 Set |
パッケージの詳細: |
export worthy packing at extra cost |
納期: |
90 days |
供給能力: |
- |
支払いタイプ: |
T/T, L/C |
製品グループ : |
Air Pollution Control Device
|