Analysis retains crucial role in alloys sector
While hand-held analyzers remain vital in the metals recycling sector, bulk analyzers by companies such as Sicon of Germany also could soon play a role.
Photo courtesy of Sicon GmbH.

Analysis retains crucial role in alloys sector

In addition to hand-held analyzers at the scale, bulk analysis is poised to grow in importance.

September 15, 2020

When the hand-held metal analyzer “gun” was introduced to the scrap industry in the late 1990s, it provided an important tool metal recyclers could add (along with their benchtop units) to confirm the chemistry of the scrap they were purchasing.

The hand-held analyzer market remains competitive, with several technology and equipment vendors introducing an annual stream of upgrades and new capabilities for the models they offer.

Considering the vast number of nonferrous (and ferrous and stainless) alloys used globally—with new ones introduced each year—research, development and follow-up features are likely to remain part of the picture.

Seeking speed, durability and versatility

A new or improved analyzer can distinguish itself in several ways, but three of the critical factors—beyond the prerequisite of accuracy—are speed (how fast an accurate reading can be made), durability (building a unit that can handle drops and other “dings”) and versatility (using one gun for as many tasks as possible).

Woburn, Massachusetts-based SciAps Inc. bills its X-550 model as “the lightest, fastest X-ray gun ever made.” The company says its hand-held analyzer “delivers blistering speed on aluminum alloys especially, and [detects] residual metals in steel.”

In addition to marketing its analyzer to recycling plant operators, the firm has been gauging interest from demolition contractors. Demo contractors who generate significant amounts of metal at dismantled power plants and refineries will want to ensure they know what it is they are selling to their scrap buyers.

On the versatility front, SciAps touts the apps that come with the X-550, including ones for aluminum alloys and another for precious metals. It also says its “new laser gun (the Z) segregates steels and stainless by carbon content.”

Japan-based Olympus Corp., which in the United States is based in Massachusetts, bills its new for 2020 Vanta Element-S hand-held X-ray fluorescence (XRF) analyzer as being able to deliver “fast light element detection at an affordable price.”

The company says the Vanta S model is equipped with a silicon drift detector (SDD) to analyze light elements, such as magnesium, aluminum, silicon, sulfur and phosphorus, in alloys. According to Olympus, the Vanta S “effectively measures ferrous metals, aluminum, copper, stainless steel, nickel and gold karats” and “offers clear on-screen grade ID and comparison for the light elements magnesium, aluminum and silicon in seconds.”

Thermo Fisher Scientific Inc., also based in Massachusetts, says the Niton Apollo hand-held laser-induced breakdown spectroscopy (LIBS) analyzer, one of its newest models, offers improved speed, increased accuracy and greater mobility.

Versatility is one of the Apollo’s hallmarks, according to Thermo Fisher. “In addition to quantifying carbon concentrations in low alloys and low- and high-grade steels, the Niton Apollo also more accurately measures aluminum, chromium, copper, iron, manganese, molybdenum, nickel, silicon, titanium, vanadium, tungsten, carbon equivalency and pseudo-elements,” the firm states.

Japan-based Rigaku Analytical Devices, with U.S. headquarters in Texas, has emphasized the durability of its KT-100S model. It says the hand-held analyzer “is MIL-STD 810G drop-test certified and IP-54 dust protection rated, making it ideal for use in scrap metal yards.” Because the KT Series of hand-held LIBS analyzers uses a laser excitation source, there are minimal to no regulatory licensing requirements, the firm adds.

While hand-held analyzer models compete for scale house and scrap purchasing attention, one downstream shredding separation technology provider sees a bulk role for the technology.

Lasering in on downstream analysis

Germany-based Sicon GmbH, which also has an office in Georgia in the U.S., says its LaserSort can be used in several bulk applications, including sorting the “heavies” portion of shredded scrap into zinc, lead, stainless steel, copper and brass fractions.

The company also has designed a product called EcoSort to analyze and record the ferrous scrap output of shredding plants.

“The LaserSort is [placed] at the final end of a downstream system,” the company’s Heiner Guschall says. “It comes after the eddy current separation and is a replacement for optical sorters and partly also XRF and some XRT [X-ray transmission] sorters. Usually, the accuracy is much higher. The idea behind the LaserSort is that we sort based on chemistry and not based on color.”

Not all shredder feedstock “is suitable for the LaserSort” initially, Guschall tells Recycling Today. “Proper screening, removal of cables and printed circuit boards are necessary. Sometimes additional cleaning steps are necessary. If so, we integrate them into the process.”

In addition to clean feedstock, programming is a key to plugging the LaserSort into an application. “Sixty percent of the tasks we have to do are very specific,” he says of Sicon’s recommended use of the LaserSort. “For example, foundries that need to [extract] certain unwanted impurities before the smelter, and special metals that are today still hand sorted by analyzing and sorting piece by piece.”

He continues, “In these processes, we can automate and lift to a higher level of productivity. Often also, aluminum recyclers come with specific specifications we can generate out of a mixture. In all cases, we adjust the sorting parameters and sometimes also the algorithm behind the software.”

In the downstream “heavies” application, Guschall says the LaserSort can “achieve throughput between 2.5 and 3 metric tons per hour.” In some aluminum-specific sorting applications, “it depends on the specific weight,” he says, but the throughput could be roughly half that.

While Guschall says labor costs can be reduced, he says just as crucially quality can be improved. “The principle of the LaserSort is that we separate completely and automatically without any manual handpicking. We analyze each piece of metal and assign it to sorting stations where the material is ejected according to the [programed] selection of the customer.”

He adds, “The advantage is that we can detect light as well as heavy metals. That is unique and is a real step ahead for the quality of metal sorting.”

Guschall says a LaserSort is currently operating at an electronic scrap shredding facility “and is used for the final refining of the heavies metal mix as well as for the plant’s aluminum mix.”

Tests with other customers have him convinced that unit will soon be joined in the field by others. “It is more than likely that next year, four or five further systems will be installed since the test runs have shown very good results.”