A new, resource efficient cascade procedure for cleaning aluminum parts saves 50 percent of both energy and fresh water while reducing carbon emissions by one fourth.
Lighter cars use less energy per kilometer. This has led to doubling the percentage of aluminum parts in automobile construction over the past 20 years. Thus, lightweight construction contributes to reducing carbon emissions while driving. All the same, if we wish to reduce a car’s overall carbon footprint, we must consider the emissions released throughout the entire production chain.
After molding a part, the aluminum surface is extremely dirty. Before carmakers can integrate the part into the construction process, the dirt must be removed. Normally, this cleansing requires enormous amounts of water, chemicals and energy. Targeting a major reduction in all three, Holder GmbH Surface Technology has developed a new resource efficient procedure for cleansing aluminum parts.
The company’s cascade cleansing procedure takes place in a series of baths. The first bath holds detergents, salts and ultrasonic to degrease the part. The ensuing three baths rinse it. In the first bath, submersion displaces water which is collected and fed back into the procedure – requiring less fresh water and subsequently less waste water to purify. Chemicals in the displaced water naturally flow back into the degreasing bath, reducing the need for new chemicals. Combining a dehydrator and convection dryer increases energy efficient drying. The dehydrator air stream flowing from one side is vacuumed up on the other side and redirected to the dehydrator. A block-type thermal power station (BTTP) produces the entire energy supply for the baths and dehydrator.
This procedure saves the mid-sized, Baden-Württemberg business approximately 13,000 m3 fresh water, 20 tons of chemical and 770 tons of carbon emissions annually. The payback period is expected to be 3 to 4 years.
The Federal Environment Ministry’s Environmental Innovation Program (UIP) subsidized the new facility.