Large silicon carbide shapes for flash pots, quench vessels, choke tubes and vent blast tubes.
Where hot slurry and steam change direction at speed.
Silicon carbide shapes sized for the vessel, not for a catalogue.
An impingement block is the target that takes the direct hit where a high velocity stream changes direction, for example where slurry and steam leaving an autoclave enter a flash vessel. A lining that holds there has to resist abrasion, acid corrosion and temperature at once, in a large shape. Blasch casts impingement blocks and linings for flash pots, quench vessels, choke tubes and vent blast tubes in nitride bonded silicon carbide (NITRON) and reaction bonded silicon carbide, for autoclave and pressure oxidation circuits.
In pressure oxidation, ore slurry is oxidized in an autoclave at high temperature and pressure. When it leaves, the pressure drops through choke tubes and the slurry flashes to steam in a flash vessel, carrying solids at high speed.
That stream hits whatever stands in its way. The impingement block is placed there on purpose, so the wall and the vessel lining behind it survive. Quench vessels, vent lines and the valves around them see the same mix of solids, acid and heat.
Precast silicon carbide shapes replace metal parts and monolithic linings here, because one part has to resist abrasion, corrosion and temperature at the same time.
The impingement block is meant to wear so the vessel does not, which is why it pays to make it the part that lasts longest in the whole flash circuit.
Each part is designed for one vessel and one flow, with the size and geometry the process needs.
Targets and wear blocks for flash pots and quench vessels, cast in one large shape.
Linings for the vessels where slurry flashes and is quenched, built from precast sections.
Tubes and shrouds where the pressure drops and the velocity is highest.
Autoclave and pressure oxidation plants keep growing in size and process severity. The Blasch casting process makes very large and complex shapes, which lets the designers of these circuits specify a ceramic lining system rather than adapt their vessel to standard tiles. Large and complex ceramic shapes
The main grades are NITRON (nitride bonded silicon carbide) and InVinCer RB (reaction bonded silicon carbide), both chosen for high temperature abrasion and corrosion. Nitride bonded silicon carbide
Oxygen injection nozzles, pipe and valve systems for the same circuits are made as well, see ceramic valve components. Linings for other process reactors are on reactor vessel linings, the full range on wear products. Ceramics for mining and mineral processing
A wear block placed where a fast stream changes direction, so it takes the impact instead of the vessel wall or the lining behind it.
The process casts single parts up to about two tons. Larger linings are built from several precast sections.
Both. Parts can be specified for a new circuit with its designer, or made to replace worn parts in an operating plant.
Send the vessel layout, the flow conditions and where the lining wears. A Blasch engineer designs the block and the lining around it.
