Recovery of Materials from Refrigerator: A Study Focused on Product Distribution, Recyclability and LCA Evaluation

This study outlines a recycling initiative conducted at Rekular GmbH, focusing on the recycling of 100 refrigerators. The recycling process employed a combination of manual dismantling, de-pollution, and mechanical processing techniques. Manual dismantling followed a predefined protocol to extract various materials, while the mechanical and physical processes involved Shredding, Zigzag, Magnetic, and Eddy Current Separation (ECS) to liberate and separate differ-ent materials. The resulting ferrous, non-ferrous and polymer product fractions were analyzed and categorized, providing valuable insights into the quality of interim products in the refrigera-tor recycling process. Simulations were then performed using FactSageTM and HSC Chemistry software to simulate the recovery of metals from the ferrous and non-ferrous fractions using pyro metallurgical and hydrometallurgical methods. An Electric Arc Furnace (EAF) was utilized for iron (Fe), while a Re-smelter process for aluminium (Al), and the Black Copper Route was simu-lated for copper (Cu) recovery. The recovery rates including metallurgical, mechanical, and physical processes are as follows: Fe (78%), Al (68.4%), and Cu (52.4%). In contrast, the recovery rates through metallurgical processes are as follows: Al (99%), Fe (79%), and Cu (88%). This dis-crepancy is attributed to losses of these elements resulting from incomplete liberation in mechan-ical processing. Additionally, a Product/Centric approach was applied and the recycling index reached 76% for recovery the Al, Cu, and Fe metals in a refrigerator recycling process. Turning to the environmental impact evaluation within the Life Cycle Assessment (LCA), the process unit with the highest emissions per refrigerator in the recycling process was the use of nitrogen dur-ing the shredding process, accounting for 3.7 kg CO2 eq/refrigerator. Subsequently, the con-sumption of medium voltage electricity from the German grid during mechanical and physical separations contributed to 0.6 kg CO2 eq/refrigerator. The EAF, and Electrolytic refining stages in the metallurgical recovery process also had a notable impact, generating 10.7 kg CO2 eq/refrigerator.