The economical design of your infrastructure Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 1
Plant layout
3
6
2
1
1
1 Pre-expanding 2 Silos 3 Steam generation plant 4 Compressed air plant 5 Cooling water supply 6 Shape moulding machines 7 Recycling plant 8 Extruder
5 4
7
8
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 2
Plant layout Media
• Steam • Water • Air • Vacuum • Electricity Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 3
Plant layout Steam supply
Steam
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 4
Plant layout Steam supply Chimney Pressure reducing valve 0.2-1.2 bar
Feed water tank Locking valve Steam boiler
To shape moulding machines
Water conditionin g plant
To preexpander
Pressure reducing valve Main steam line
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 5
Plant layout Steam supply, steam boiler
Taking out of steam in batches
Steam consumption during purging and autoclave steaming higher than capacity of generator (steam boiler)
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 6
Plant layout Steam supply, principle steam accumulator
Energy output by opening of steam valves: è low evaporation temperature è water evaporates abruptly by pressure decrease
Baffle sheets Steam pipe Steam
Water level control
Water Steam from boiler Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 7
Plant layout Steam supply, pipes
Steam pipe
Steam velocity » 25 m/s ü
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 8
Water quality Conditioning of the boiler feed water
Conditioning of the boiler feed water Aim:
to eliminate negative effect of water components
Negative components:
lime (water hardness) iron silicates oxygen carbon dioxide
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 9
Water quality Conditioning of boiler feed water
• Optimum temperature of feed water between 95 and 110 °C
• Feed water tank designed as degassing station (pressure 0.2 – 0.6 bar)
• Removal of the gases responsible for corrosion (CO2 + O2)
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 10
Water quality Conditioning of the boiler feed water
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 11
Water quality Corrosion - „Carry Over“, example
Corrosion at steam chamber, 2 years old !
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 12
Water quality Corrosion - „Carry Over“, example
Steam outlet: original material thickness 15 mm, in this case only 3 mm !
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 13
Water quality Corrosion - „Carry Over“, example
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 14
Water quality Corrosion - „Carry Over“, example
Steam chamber useless because of corrosion Cause: „Carry Over“ of steam accumulator Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 15
Water quality Corrosion - „Carry Over“
„Carry Over“ caused by... 1. High decrease of pressure in accumulator or boiler 2. Unfavourable removing outlet at accumulator or boiler 3. Pipe diameter too small
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 16
Water quality Corrosion - „Carry Over“
Indication and increase of „Carry Over“ effects in case of ... • unusually strong corrosion • excessive conductivity values of the condensate • boiler or steam accumulator not regularly cleared from mud • frequent stand-still times of machines
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 17
Water quality Corrosion - „Carry Over“
How a „Carry Over“ is indicated and noted • recommended conductivity value for boiler:
< 5 mS/cm
• recommended conductivity value accumulator:
<< 1 mS/cm
(theoretical conductivity inside the accumulator
= 0 mS/cm)
at a sample temperature of 25 °C • recommended pH – value boiler water:
between 8 and 9
condensate has pH – value of 7 region 1 - 7:
acid
(drags at finger test)
region 7 - 14:
alkaline/soapy
(smears at finger test)
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 18
Water quality Corrosion - „Carry Over“
4. Regular measuring and control of the water values of the plant
measuring of total hardness of water
pH - value measuring conductivity measuring
measuring content of ferrous metals
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 19
Plant layout Water supply
Water
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 20
Plant layout Water supply
Water is required for: • Condenser cooling • Mould cooling • Vacuum pumps • Steam generation
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 21
Plant layout Water supply Cooling tower
Cooling water circulation pumps
Water circuit Condenser and vacuum pumps
Water pressure tank
Fresh water supply max. min.
Hot water cycle for mould cooling Level switch
Hot water 50°C Pumps for hot water
Overflow Pumps for cold water
Cold water 25°C
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 22
Plant layout Water supply Optimum:
2 Water circuits
Hot water circuit
Cold water circuit
• 50°C
• 25°C
• to cool moulds
• to cool condenser • seal water for vacuum pumps
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 23
Plant layout Water supply
Advantages of 2 water circuits ð Reduced water consumption ð Faster temperature decrease at mould ð Reduced cooling tower capacity ð Dryer mouldings
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 24
Plant layout Water supply
Principle of heat transfer during vacuum cooling Phase 1:
Aluminium plate (hot) under steam atmosphere (condition of steam chamber before cooling)
Steam
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 25
Plant layout Water supply
Principle of heat transfer during vacuum cooling
Phase 2:
Water is injected, (step „condensation“)
Water injection Water film
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 26
Plant layout Water supply
Principle of heat transfer at vacuum cooling
Phase 3:
Water evaporates under vacuum („stabilization“)
Vacuum (< - 0.6 bar) Water film
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 27
Plant layout Vacuum system
How a condenser works Steam Vacuum
Water Outlet Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 28
Plant layout Water supply Condensate with EPS beads
EPS beads accumulate at surface
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 29
Plant layout Vacuum supply
Vacuum
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 30
Plant layout Vacuum supply
Reasons for the use of vacuum during stabilization : ð faster cooling through evaporation ð moisture reduction in the mouldings ð reduction of stabilization time ð shorter cycle times
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 31
Plant layout Vacuum supply
Single vacuum
Central vacuum
• one or several pumps at one machine
• central vacuum station with 4 or 6 vacuum pumps
ð pumps are running continuously
ð some pumps are running continuously ð remaining pumps are only used when needed
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 32
Plant layout Vacuum supply
Advantages of the central vacuum system: • Vacuum is available much faster • Fewer pumps are required than for single vacuum ð reduced energy consumption ð energy saving ~ 30 - 50 % ð reduced need for spare parts • Increased production safety Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 33
Plant layout Compressed air supply
a b 9 – 7
a b 4
ir a r
ir a r
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 34
Plant layout Compressed air supply
Air is required for : • Control air • Fill injector
High pressure
• Compressed air in general
• Pressure fill tank
Low pressure
• Demoulding • Drainage Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 35
Plant layout Compressed air supply Kick back valve
Air tank HP (control and filling air 9.0 bar)
Air tank LP (Transfer and ejection air 4.0 bar)
Compressor HP 9.0 bar
Condensate outlet Fresh air Compressor LP 4.0 bar
Stand by compressor
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 36
Plant layout Compressed air supply
Optimum:
2 air circuits Low pressure
High pressure
• 3...4 bar
• 7...9 bar
• Demoulding
• Control air
• Drainage
• Filling air
• Pressure fill device Air quality:
clean, dry, oil-free Þ use filter, oil separator and cooler
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 37
Plant layout Compressed air supply
Specifications for compressed air Temperature
: < 30° C
Techn. dust-free
: No solid particles > 10 µm particle size
Techn. oil-free
: Content of residual oil < 0,01mg/m³
Humidity
: When a cooler is used only water drops < 3 µm are in the compressed air, low humidity
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 38
Plant layout Compressed air – water content depending on the temperature
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 39
Plant layout Water content in compressed air
Quelle:
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 40
Raw material and product transport Ways of conveying
ð Mechanical transport systems ð Pneumatic transport systems
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 41
Material conveying Basics
Material transport
Raw material transport
Transport or pre-expanded material
1
2
To pre-expander
Mechanical transport
From pre-expander to silo
Pneumatic transport
Pneumatic transport
3 From silo to moulding machines
Pneumatic transport
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 42
Raw material and product transport Raw material conveying
ð Careful transport ð Avoidance of abrasion of the thin material coating ð Avoidance of lumps
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 43
Raw material and product transport Raw material conveying to the pre-expander Material feeding through suction pipe
air
Material feeding through hopper
air
fan
dust separator
fan
dust separator
material
material suction pipe hopper octabin
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 44
Material transport Ways of conveying
Low loading (1....10%) EPS share
Air share
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 45
Material transport Means of conveying
Packing density (%)
Density (g/l)
Conveying distances (m)
Venturi
Suction
Cellular wheel
0,75 - 1
3 – 10
8 – 20
8 – 20
10 – 40
10 – 150
- 10
- 150
- 300
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 46
Filling methods Conveying speed
Conveying speed (m/sec) • between 10 u. 16 m/sec • < 8 m/sec – danger of clogging • > 18 m/sec – density increase Venturi – highest conveying speed Cellular wheel – lowest conveying speed, most careful conveying
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 47
Cellular wheel sluice Basic design Conveying pipe
Material
Cellular wheel sluice
Fan
Cellular wheel
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 48
Raw material conveying Pneumatic conveying Injector principle Material
Fan
Air
Conveying pipe
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 49
Raw material conveying Pneumatic conveying
Suction and conveying via fan
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 50
Material conveying Outlet box
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 51
Material conveying Discharge of the silos
Even flow
Uneven flow
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 52
Material conveying Discharge of the silos
„Bridges“ are built
„Wells“ are built
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 53
Material conveying Discharge of the silos
Discharge with uneven flow
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 54
Material conveying Pipes
Aim:
From the feeding station to the material processing place the density has to be kept as constant as possible!
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 55
Material conveying Pipes / pipe bends Bending radius R = < 2 x D
Bending radius R = > 2 x D
Bending radius = R Pipe diameter = D
Bending radius = R Pipe diameter = D
Material accumulation
no material accumulation
ð no even material flow
ð Even material flow
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 56
Material conveying Pipes „hard“ pipe fitting
„soft“ pipe fitting
Material accumulation
no material accumulation
ð no even material flow
ð even material flow
ð danger of clogging
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 57
Material conveying / blowing Density and conveying distance depending on pipe diameter Density EPS [g/l]
P ... const. i ... const.
30
20 D ... 50 mm D ... 100 mm
10
D ... 200 mm
0
100
Conv. distance L [m] 200
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 58
Material conveying / blowing Density and conveying distance depending on number of bends Density EPS [g/l]
P ... const. D ... const.
30
20 4 pipe bends 6 pipe bends
10
8 pipe bends
0
100
Conveying distance L 200[m]
Kurtz GmbH 03.09.00.smvs-mb/jd-us
In-house fair 2002
page 59