High efficiency cyclones and dry spray particle agglomeration (TSA)
High efficiency cyclone separators
Still today, cyclone separators used for the separation of particles from gases have their place in process and environmental technology. being it for applications at high temperatures or handling aggressive gases where bag house filters, wet scrubbers or electrostatic separators cannot be used, cyclones can provide the required solutions.
Over many years, we have in our own laboratory optimised our cyclone design. So we could maximize the separation efficiency and at the same time reduce the pressure loss of the cyclones. we also have developed our own software package for the process design of cyclones. This software is available to our clients.
The large cyclone shown on this picture operates at 850 °C and only a small pressure loss is available. The cyclone separates 99 % of all particulate greater 100 µm at a total pressure loss of only 2 mbar.
In teh meantime, our activities have changed from a hardware manufacturer to a know how provider as we supply cyclone technology to licensees worldwide. Our services entail the training of clients personnel, the process design of cyclones and if desired the complete design including workshop drawings. We also support licensees with enquiry specification if external manufacturing is planed. .
The patented dry spray particle agglomeration system
Based on many years of testing and development we have related a unique system to agglomerate fine particles in a hot gas stream upstream of teh particulate separation device. Small droplets of water are injected with specially developed spray nozzles into the gas stream. Before the water droplets evaporate, they will accumulate fine particles, and when the water droplet is fully evaporated, then the particles will have agglomerated to a larger, easier to separate particle. Therefore, by using this system, teh efficiency of conventional gas cleaning equipment is enhanced considerably.
The dry spray agglomeration system can by employed in systems where the gas temperature is above 200 °C and can be installed upstream of cyclones or ESP. It also can be used upstream of wet scrubbers.
As can be seen in the diagram, the efficiency of particle agglomeration depends largely on teh size of the water droplet.
Normal water spray nozzles however only create the required droplet size with considerable water flow which is unsuitable to most applications. Therefore we have developed a special spray nozzle which generates the correct, optimum droplet size at very low water flow.
With this system the temperature loss in the gas is low and therefore the evaporation of teh droplet and the agglomeration of the particle is possible. Furthermore the energy loss is minimized.
Diagram Author: "Target efficiency in a spray tower, [Staimand J. Inst. Fuel, 29, 58 (1956).]"
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The water spray arrangement can also be installed inside a cyclone, where the spray nozzles will be protected from blockages by the dirty gas. With other systems, the spray nozzle arrangement is installed in protective tubing in the hot gas duct. |  |
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Examples
PG Bison Stellenbosch, South Africa
Chip dryer in a particle board factory
Gas cleaning with ALERA high efficiency cyclones.
Emission without TSA = 120 mg/Nm3 .
Emission with TSA = 20 mg/Nm3
. Commissioning 2000
Transvaal Sugar Board – Malelane, South Africa
Steam boiler 160 t/h with bagasse & coal firing.
Particle load in flue gas 5000 mg/Nm3 (20 % < 5 µm)
Final gas cleaning with wet scrubber
Emission without TSA = 380 mg/Nm3
Emission with TSA = 85 mg/Nm3
Through research and development we reach
ecconomic, efficient system for teh environment.
