LED phosphor processing

Homogeneous LED phosphor materials

Freeze Granulation offers a unique technology for to make homogeneous LED phosphor materials resulting in improved photoluminescence properties and thus, Freeze Granulation will give you high power LEDs with superior final properties. Most LEDs that are emitting a soft white light have been covered by a yellowish phosphor coating or plate usually made of cerium doped yttrium aluminium garnet (YAG:Ce) crystals, which have been processed using powder processing techniques and bound into a ceramic plate, glass or with a resin.

Please contact us for more information and a test-granulation of your powder system.

 

Homogeneity preservation from suspension to dry granule

If you are looking for optimal homogeneity in your granulated material, then you should evaluate our unique granulation technology – Freeze Granulation! 

Today, Freeze Granulation is the only granulation technology that will preserve the homogeneity from suspension to dry granule, which is crucial for good results in most processes.

Spray cooling or rather called spray freezing is the first step in the freeze granulation process where a suspension is atomized, sprayed with a nozzle, into a chamber with liquid nitrogen. The small droplets are then rapidly frozen with a minimum of ice crystal growth. The frozen material (granules) are then transferred to a freeze dryer where the ice is removed by sublimation, i e never go through a liquid state that ensure homogeneity preservation.

Spray-freezing and freeze drying

Spray-freezing and freeze drying – Freeze Granulation

PowderPro AB develop, manufacture, market and sell equipment and know-how for Freeze Granulationspray freezing and subsequent freeze drying (lyophilization or cryodesiccation). Freeze Granulation was developed in late 1980s at Swedish Ceramic Institute in Göteborg and it is also a development of Spray Freeze Drying (SFD) and Spray Freezing into Liquid (SFL).

Spray cooling or rather called spray freezing is the first step in the freeze granulation process where a suspension is atomized, sprayed with a nozzle, into a chamber with liquid nitrogen. The small droplets are then rapidly frozen with a minimum of ice crystal growth. The frozen material (granules) are then transferred to a freeze dryer where the ice is removed by sublimation, i e never go through a liquid state that ensure homogeneity preservation.

Below you can see an illustration of the Freeze Granulation process.

Please contact us for more information and a test-granulation of your powder system.

Freeze granulation illustration
Freeze Granulation illustration

Chemical-Looping Combustion (CLC)

Freeze Granulation of Chemical-Looping Combustion (CLC) system

Environmental and energy engineering (Greenhouse Gas Control Technologies): Oxygen-carrier particles for chemical-looping combustion (CLC) have been manufactured by freeze granulation for improved environmental combustion of coal and fuel gases (syngas). Freeze granulation ensures homogenous distribution of the porosity and of the active material in the particles (ex NiO) and, hence, provides reliable performance. This advantageous characteristic can be extended for use in production of all kinds of catalytic particles for various processes.

See link for a paper on the application of Freeze Granulation in CLC: Prospects of Al2O3 and MgAl2O 4-supported CuO oxygen carriers in chemical-looping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU)

Please contact us for more information and a test-granulation of your powder system.

CLC_Mehdi_Licenciate Thesis_Chalmers_Sweden

Diamond powder processing

Freeze Granulation is today being used by market leaders in manufacturing of diamond tools like diamond wheels using PCD – Polycrystalline Diamonds. Homogeneous distribution of the active component, diamond particles, in diamond wheels is very important for the cutting performance and tool life. By using Freeze Granulation you will bring your slurry, with diamonds, in the powder-mixture/dispersion to homogenous granules of diamond particles with inorganic fillers and binders, which results in improved cutting performance and tool life in the pressed and sintered advanced diamond composite product.

The granules should only be sufficiently big. As we get the diamonds homogenously distributed in suspension they will be homogeneously distributed in the granules. The risk to get agglomerated diamonds is bigger if you add diamonds after the granulation step.

Diamond composite granules
Spherical homogeneous diamond granules – no donuts!

 

Zeolite granulation

Freeze Granulation of zeolite materials offers the possibility to produce very soft, spherical granules which show an excellent flowability. The granules can be compressed to compacts of high homogeneity and they are completely redispersableFreeze Granulation is a granulation technique which combines the advantages of spray drying and freeze drying. Hard granules and agglomerates are prevented by this technique excluding capillary forces during drying.

Please contact us if you would like to test-granulate your powders or chemicals.

Last day at CERAMITEC 2012

A busy morning with many good discussions on how to apply Freeze Granulation in different ceramic systems.

Last day at CERAMITEC 2012

Third day at CERAMITEC 2012

The third day at CERAMITEC 2012 was intensive with many new and interesting meetings, especially within nanopowders, but also many in ceramic powder processing.

Ceramitec 2012 Third day

Second day at CERAMITEC 2012

Today we welcome our customers to the second day at CERAMITEC 2012. We have had several good discussions on new applications of Freeze Granulation of different ceramic powder systems.

Second day of CERAMITEC 2012