Ceramic Industry

Finding a Toll Processing Solution

May 1, 2012

compass globe map goldManufacturers can increase profits by contracting their toll processing and material sizing needs.

Manufacturers seldom look for solutions to problems they can’t see. If operations are going well, they do not need fixing—or in some cases, do not deserve attention at all. For toll processing and material sizing processes, however, this can be a costly mistake.

Companies that process on their own often believe they cannot afford to pay someone else to handle their toll processing and material sizing. Others might assume that inconsistent product or low yield is a direct result of inconsistent feed material, as they cannot quantify a vendor’s quality process or simply do not have the time to do so. Even if a company wants to make a change, the potential amount of time required and assumed risk make it difficult to begin the process.

Economic Implications

In general, most manufacturers are trying to do more with less in this economy by not replacing personnel who have retired or left as a result of layoffs, reducing hours, closing plants, etc. Because of this trend, a lot of knowledge and expertise is leaving and not coming back. On the other end of the spectrum, reducing costs and cutting budgets have led to equipment being replaced less often and, in many cases, maintenance not being performed on a timely basis.

How do you increase profits by contracting your toll processing and material sizing needs? Have you considered outsourcing classification, pulverization, blending, screening, and/or particle modification services? Can you afford not to?

It may make sense to outsource this facet of your business to professionals who have the proper equipment, knowledge and experience working with a variety of materials. They not only can handle your processing needs efficiently and effectively, but can possibly apply knowledge gained from other jobs to help improve yours.

Manufacturers that outsource materials processing are not burdened by additional capital investment or the depreciation of new equipment. They can remain focused on current product lines while developing new products out of existing materials through outsourced toll processing. Using experienced toll processors also eliminates extended lead times for equipment delivery and installation, as well as the need for in-house engineering expertise in handling materials, equipment setup, operation requirements, maintenance or spare parts management, facility floor space, clean air compliance, or processing permits. In addition, the time that strategic planners spend analyzing current resources in remaining stock or waste material can be used differently.

These changes can often yield important return on investment. Manufacturing costs are predictable, and turnaround is fast. The burden of obtaining consistent product is transitioned, and quality processes and procedures can improve as the focus is more narrowly defined with a company specializing in toll processing. As an added benefit, managing production schedules, training, operation cost, safety concerns and potential liabilities are also transferred.

Real-Life Applications

As previously mentioned, one of the potential benefits of contracting toll processing and material sizing needs is access to the expertise and ingenuity of personnel who are focused on toll processing. In one example, PTI received an opportunity to process a high-density crystalline material that several other processors had attempted and failed to process to the correct particle size with an acceptable yield.

The raw material was provided in blocks of approximately 10-15 lbs each. The manufacturer requested a finished product particle size of minus 100 mesh (150 micron) plus 270 mesh (53 micron). The solution required a multistage process approach involving more than one type of mill. First, the large blocks of feedstock were reduced to minus 20 mm using a jaw crusher. The jaw-crushed material was further reduced to minus 3 mm size using a hammer mill fitted with boron hard-faced hammers. The hammer-milled material was subsequently passed through an opposed-jet mill with an integral vane-type classifier, further reducing particle size to approximately 80% minus 100 mesh.

The next stage involved passing the jet-milled material through a vibratory screen, producing three fractions, including undersized fines, product to size, and oversized coarse material. Finally, the oversized coarse fraction was re-milled and screened to produce additional product at the target size.

This multi-step, custom approach in size reduction for a challenging material was developed in various stages. While an initial approach produced quality product within customer size specifications, the processes generated a large amount of unusable fines, resulting in a relatively poor product yield of approximately 40% of the material received.

A second method of sizing involved widening the gap in the jaw crusher, which produced fewer fines at this stage. The optimal gap setting was determined through a series of test runs in order to minimize undersize fines. Milling pressure was also reduced by 45% in the jet mill, lowering the energy level applied to the milling chamber and causing less fine particle fragmentation. This second approach reduced fines formation significantly and improved product yield to 54% of material received.

A third approach involved the replacement of the jet mill secondary or strip air blower in order to boost airflow through the mill classification zone. This improvement increased classification efficiency of high-density materials and ultimately increased product yield to 60% of material received. PTI continues to process this material while making additional process modifications to enhance product yield.

Many materials require a complex sequence of procedures in order to achieve the highest product yields. The approach taken to optimize this particular manufacturer’s product, while being unique to that material, is typical of how a toll processor can use their personnel’s experience and their available equipment to achieve the manufacturer’s desired product at the maximum yield.

Long-Term Success

Many manufacturers have benefitted from successful relationships with toll processors. By accessing a broad spectrum of custom services and a wide array of expertise, outsourcing your toll processing needs can provide multiple advantages for the long-term success of your business.

 For more information, contact Powder Technology, Inc. at (952) 894-8737 or visit www.powdertechnologyinc.com.