Genie in a bottle: Shred-Tech

Genie in a bottle: Shred-Tech

Shred-Tech Sales Manager Sean Richter talks to Waste Management Review about the company’s 20-year history in e-waste recycling and data destruction. 

Governments and manufactures of electronic hardware are increasingly coming under pressure to implement policies and practices around safe e-waste disposal.

E-waste’s status as a problematic waste stream has a long history. In 1976, the United States Resource Conversation and Recovery Act made it illegal to dump e-waste. Likewise, in 1989 the Basel Convention made it illegal to dump e-waste in developing countries.

As a Basel Convention signatory, Australia is bound to this agreement. E-waste is also banned from landfill in Victoria, South Australia and the ACT.

Legislative measures like these are incentivising recycling equipment manufactures to engineer technology and machinery capable of processing multiple material components present in electronic products.

Shredding and recycling system manufacturer Shred-Tech has been in business for over 40 years. Sales Manager Sean Richter says in that time, the company has designed and manufactured some of the largest e-waste reduction systems in North America.

“These systems were originally designed to use high horsepower and brute force to shred and granulate everything from large main frame computers, military electronics, telecommunications equipment and high-tech electrical switching gear,” Sean says.

As electronics have become considerably smaller and lighter than Shred-Tech’s initial systems were designed for, the equipment and processes have evolved.   

“Today’s systems have advanced to encompass newer technologies in reduction, usually with lower power requirements, better material handling and separation of the materials prior to smelting or electrochemical processes for extraction,” Sean says.

An end-of-life laptop or phone could expose the financial records, health records, photographs and personal communications of its prior owner. Data and privacy is therefore a key consideration for e-waste recyclers.

According to Sean, the level of shredding provided by Shred-Tech plants makes it virtually impossible to extract data from the end material.

“Computers and telecommunications equipment are subject to massive reduction forces, shattered into hundreds of fractions and mixed with thousands of other materials before heading to final recyclers. Finding one with usable data would be like finding the genie in the bottle.”

Sean says one of the challenges with e-waste processing is how varied the waste stream is, encompassing a range of materials requiring different cleaning and processing methods.

“We have designed and built custom machines and systems ranging from portable hard drive shredders, systems that shred only circuit boards and stand-alone machines designed primarily for destruction purposes,” Sean says.

A key component of Shred-Tech’s business is the design of modular e-waste shredding plants.

“Our shredding systems can be custom configured using proven system modules to meet specific capacity and separation requirements,” Sean says.

“The systems reduce and separate component material such as plastic, aluminium, copper, steel and precious metals.”

According to Sean, a typical Shred-Tech e-waste recycling plant starts with an incoming triage.

“The triage sorts material into type slots, such as hazardous material, material suitable for manual disassembling and resaleable components like integrated circuit chips and power supplies,” Sean says.

The next stage is primary reduction, typically completed by a large twin shaft shredder.

“The goal during primary reduction is to break the material into sortable fractions. The material is then sorted manually on pick lines or via magnets and additional size screening devices,” Sean says.

“Ferrous-based and commingled material is then removed by an initial magnet before being sent for secondary reduction and liberation to minus 50 millimetres.”

According to Sean, there are several schools of thought on how to best achieve secondary reduction. The first is sending all ferrous based material to a high-speed reduction unit such as a ring mill.

“The ring mill liberates all ferrous material with the help of a secondary magnet and removes clean steel for resale. All remaining materials carry on to secondary reduction,” he says.

“Others like to send all material to a large four shaft shredder for liberation and final reduction. I find the high content of ferrous material in this stream results in accelerated wear, however, and leads to high maintenance costs for the four-shaft shredder.”

Following this, material fines are removed by screeners, which eliminates all particles minus two to five millimetres. Sean says removing fines enables increased tuning of the downstream separators.

“All material is then passed over by an eddy current for aluminium removal. Additionally, the stream is then sorted manually to ensure the highest purity of aluminium for resale.”

Remaining materials such as circuit boards, copper and plastic continue to further separation. “The plant then optically sorts using a wide variety of technologies that specifically targets plastic of colour, green circuit boards, wire, copper and other materials into various resalable streams,” Sean says.

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