Extending Centrifuge Dewatering into the Dryer Realm:

Washing & Drying in a Centrifuge using Hot Air/N2 or Steam

Pressure Added Centrifugation

PAC®

hc

Fcen

FP

6 bar

What is PAC?Pressure Added Centrifugation (PAC).

A unique system that enables the Heinkel Inverting Filter Centrifuge to dewater and then wash and dry products in the bowl of the centrifuge by introducing high-pressure air, N2 or steam into the sealed basket where solids are collected - while still under rotation. The only exit path for the air or steam is via the cake void spaces.

Pressure Added Centrifugation = PAC®

FC

FS

FC

FS

FC

FS

∆pCapillary Forces

Centrifugal Forces

∆p ∆p

seal betweenfeed pipe androtating bowl

Nitrogen withup to 6 bar

rotational speedcan be reducedduring pressurestep!

PAC® also Improves Cake Consistency

Before PAC – Paste Like After Pac – Solid Product

► Difficult-to-filter products can be dewatered►Products will not stick to the Solids Housing► No cannon-balling in dryers

6 bar

PAC can also improve the cakeconsistency, e.g. thixotropiccakes, which may stick onthe Solids Housing.

Pressure-Added-Centrifugation(PAC) to pre-dry the filter cake. Will avoid problems coming From discharging a “wet” cake.

Product Drying with JETSTREAM®

PAC: N2 removes liquid mechanically out of cake capillaries

Jetstream: heated nitrogen removes solvent by evaporation

PAC: 6 bar N2

Atmospheric pressure

► PAC + Jetstream of HEINKEL enables to process and handlea wide range of very difficult and problematic products

Jetstream: N2 and temperature

.Test with standard centrifugation (no PAC !!) LOD > 55 % LOD

Wet and Sticky Products = Product Loss

Test with Pressure Added Centrifugation: LOD = 20%

Surface Moisture Removed = Higher Throughput and Profitability (minimal product loss)

Filling

Suspension

`

toFiltrate-receiver

Washing

Wash liquid

toFiltratereceiver

Spinning – Cake dewatering

ToFiltrate-receiver

Filling Washing Spinning Discharging

HypercentrifugationPressure Added Centrifugation PAC®

≤ 6 bar

To Filtrate

Receiver

Vent of BowlNitrogen

Real Pressure Added Centrifugationis only possible with theHEINKEL Inverting Basket!

Discharging of Filter CakeFilling Washing Spinning Discharging

Pressure Added CentrifugationPAC® — Examples

Product nameResidual moisture

centrifugationResidual moisture with PACHYPERCENTRIFUGATION®

Antiallergical Substance

Alkaloid

Food Additive

Metal Powder

Silicon Carbide

Vitamine

30 %

45 %

22 %

26 %

19 %

39 %

11 %

32 %

5 %

12 %

6 %

24 %

► PAC reduces significantly the residual moisture! ► Inverting Filter Centrifuges is the only type which

can operate with pressure centrifugation!

Fixed Bed Drying • Sealed Cake Design Ensures Even Flow Through Cake

• High Heat & Mass Transfers… Ensures Rapid Evaporation

• Overcomes Surface Tension & Reduces Viscosity of Moisture

• Temperatures of up to 125°C Pressures up to 6 bar g

• LOD’s: from 14% to 0.002% (in 16 minutes) water wet pharmaceutical from 22% to 3% (in 5 minutes) MIBK wet polymer from 11% to 0.08% (in 20 minutes) IPA wet pharmaceutical

HF Inverting Filter Centrifuge

The PAC Difference

API after Discharge without PAC

API after Discharge with 20 minutes of PAC at 100 deg. C