Polyvinyl chloride
원료
VC
생산물
polyvinyl chloride
적용
To manufacture suspension PVC by a batch process.
설명
Description:
The process is marked by a number of significant advantages: low investment and production costs, large reactor technology, clean reactor wall technology, low personnel requirements, reliable and environmentally safe process and high-quality products.
In the suspension polymerization process, the vinyl chloride monomer is finely dispersed in water with the aid of protective colloids (1). The polymerization (2,3) is initiated by means of activtors at a suitable temperature.
The heat of reaction released during the polymerization (approximtely 1.5 * 10 6 J/kg) is removed by cooling water recycle through the reactor cooling jackets. For intensified heat transfer, chilled water units may be provided as option.
After polymerization the polymer slurry is treated in an intensive degassing system (4) to remove unreacted monomer. The VC monomer is compressed, condensed and returned to the process.
The solid polymer is separated from the aqueous phase by a centrifuge (5).
The wet polymer from the centrifuge is dried in a cyclone dryer (6) of proprietary design. This is a single-stage dryer combining the advantages of the contact fluidized bed with those of the flash system (low energy consumption, low investment costs, low maintenance rate, low hold-up).
The dry PVC power is conveyed pneumatically to the silo unit (7).
In the suspension polymerization process, the vinyl chloride monomer is finely dispersed in water with the aid of protective colloids (1). The polymerization (2,3) is initiated by means of activtors at a suitable temperature.
The heat of reaction released during the polymerization (approximtely 1.5 * 10 6 J/kg) is removed by cooling water recycle through the reactor cooling jackets. For intensified heat transfer, chilled water units may be provided as option.
After polymerization the polymer slurry is treated in an intensive degassing system (4) to remove unreacted monomer. The VC monomer is compressed, condensed and returned to the process.
The solid polymer is separated from the aqueous phase by a centrifuge (5).
The wet polymer from the centrifuge is dried in a cyclone dryer (6) of proprietary design. This is a single-stage dryer combining the advantages of the contact fluidized bed with those of the flash system (low energy consumption, low investment costs, low maintenance rate, low hold-up).
The dry PVC power is conveyed pneumatically to the silo unit (7).
Product quality: Two types of high-impact PVC are offered: Suspension PVC modified by blending with dry chlorinated polyethylene (PE-C). The PE-C also can be made by a Hoechst AG process. Acrylate-modified PVC is manufactured by grafting VC monomer on an acrylic latex using suspension PVC technology (above).
Raw material and utilities (per 1,000 kg suspension PVC powder, including improved VC removal technology):
Vinyl chloride, kg
Water, deionized, m 3
Chemicals (basis: April '88), DM
Steam, kg
Water, cooling (Δt = 8°K), m 3
Electric power, kWh
Nitrogen, Nm 3
Compressed air, Nm 3
Water, deionized, m 3
Chemicals (basis: April '88), DM
Steam, kg
Water, cooling (Δt = 8°K), m 3
Electric power, kWh
Nitrogen, Nm 3
Compressed air, Nm 3
1.001
2.1
25
1.100
120
220
10
50
2.1
25
1.100
120
220
10
50
