LARS™ Aluminum Refining System
THE STATE OF THE ART “In-Line Aluminum Purification System”
LARS™ Treatment cleans metal by removing physical (hydrogen gas inclusions), chemicals (alkali metals) & metallurgical (alkali salts & Sludge inter-metallic) impurities. LARS™ operation is based on the proven principle of high-energy diffusion and chemically driven mass transfer. Although systems utilizing rotating gas sparging device have been available in the industry for years, only LARS offers gas preheating and other advanced features. LARS™ has over 75% degassing efficiency and over 99% inclusion removal efficiency.
With over 700 million lbs. of hard alloy processed over the past 7 years, LARS™ is effective in making the following contributions to the bottom line of a casthouse:
- Furnace pre-treatment eliminated
- Holding furnace eliminated
- No-need to have ball filter
- Pass Mil-2154 Class-AA inspection
- Significant melt loss savings
- Pay back period of under 1 year
Summary of Advanced Features
Metallurgical Sophistication:
In-Situ process gas preheating gives superior degassing and inclusion capture. Gas Preheating is achieved by making the gas flow through the passageway formed by the helical groove [machined on the O.D. of the graphite shaft] and the inner wall of the graphite cylinder. Gas captures heat from graphite cylinder, which is immersed in the molten aluminum. The gas flow path is extended 30 times its length. Preheating of gas help retain fine bubble size. [i.e. prevent the undesirable growth in the bubble] after gas contacts molten aluminum.
Attrition (intense) mixing of melt & bubbles controls vortexing and reduces “carry-over”. Vortexing is controlled by generating cross and reverse velocity vectors in the melt. Rotational metal velocity in made to increase [at point P1] and decrease [at point P2] generating intimate mixing of liquid at points Q1, Q2, Q3 etc. The resultant velocity vector has no vortexing tendency. Absence of vortexing prevents reentry of dross in upper layer of melt and reduces bubble carryover at the lower [exit] end of the reactor.
Reactor shape & slope prevents bubble agglomeration and improves efficiency for same “residency time”. Reactor Volume is increase from bottom to top in a controlled manner to accommodate increase in gas bubble volume [resulting from reduced metallo-static pressure.] This prevents bubble coalescence and keeps gas surface area higher for longer duration of gas’ total residence time in the reactor.
Thermal Stabilization:
Heater Surface Area: Multiple 1.2 kw individual heaters located into large surface area graphite heating blocks provide rapid temperature equalization.
Intelligent PLC assisted thermal control with 4 thermocouples per reaction chamber.
System sized for flow rate between 2 tons/hr and 55 tons/h.
Mechanical Easing:
Rotor change over: In less than 12 minutes
Dross Ports: Horizontal Skimming at the metal level line (no access through roof is required)
Longevity and Life:
Nitrogen Shrouding over Tiles and Heater Junction Boxes
Silicon Carbide covered graphite heating tiles
Total Quality Assurance in Metal Treatment:
Mass flow alarms, Differential temperature alarms, Rotor RPM alarms
Environmental Safety:
Noiseless & cool atmosphere around LARS reactor
PLC & Mass flow meter assisted halogen control
Chlorine sensing alarms & no environmental toxic gas release to atmosphere
Capacity Range & Foot Print:
Hexagonal Reaction Chambers
Advantages over compatible in-line system
Guaranteed Technological Superiority:
Degassing efficiency above 68
Inclusion removal to pass 60 ppi CFF
Alkali removal- Na, Ca, Li<1 ppm output
Alkali salt removal- to pass sonic Mil 2154 AA testing
Rapid return on investment:
Pay back period of under 1 year
Elimination of furnace fluxing requirement:
Many of our customers (including hard-alloy manufactures) do not use a holding furnace at all. Pretreatment in the melter is not required either (except for canstock).