Cullet Beneficiating Technology and C3MC™ Cullet
One major US amber bottler reports purchases of over 2.5 million tons of amber glass bottles per year. If GMG's technology were employed in the production of that glass at the 70% cullet usage rate, 1,750,000 tons of C3MC™ cullet could be used in the manufacturing process. This would result in increased glass recycling and would provide other significant environmental and economic benefits as outlined below.
Commingled recyclable materials awaiting sorting at a MRF.
The glass recycling industry has instituted some technical advances in recent years, principally by the use of optical sorters which allow glass beneficiators to recycle higher percentages of post consumer single color cullet (PCSCC) while still meeting glass manufacturers’ cullet specifications.
Currently, some European glass manufacturers are using up to 80% cullet, 70% of which is a combination of “bottle return’ and curbside post consumer single color cullet (PCSCC) but the growing trend to commingled collection may constrict supply of PCSCC in the future in Europe as well as in the United States. Commingled collection also threatens to reduce or eliminate glass recycling in certain communities.
In the USA, PCSCC is used to augment domestic cullet where economically feasible or where required by state law. This PCSCC cullet is both color separated and cleaned to the glass manufacturers’ specifications. These combined cullet processing steps, however, have raised the cost of color separated PCSCC to $50-$60 or more per ton for amber cullet.
This burdensome requirement to color sort cullet, still accomplished largely by hand sorting at the MRFs, imposes a costly step. It can be eliminated by the use of the GMG technology which allows for the production of amber or green glass using up to 70% non-color sorted, cleaned post consumer 3-mix cullet, or C3MC™ cullet.
C3MC™ cullet, which can be produced today by glass beneficiators, will meet the glass manufacturers’ raw material specifications except for color which, of course, is no longer necessary when used with our patented color correction technology, the Batch Reformulation Software System.
Cullet Quantity and Availability
Today’s beneficiators have the capacity to provide an uninterrupted supply of C3MC™ cullet in sufficient quantities to meet the container glass industry’s needs. Green Mountain Glass, LLC (GMG) was formed to introduce the technology to both glass manufacturers and glass beneficiators and, where necessary, to co-ordinate the production and delivery of C3MC™ cullet by beneficiators, who would enter long term contracts with glass manufacturers. The supply of C3MC™ cullet will initially be available at a limited number of beneficiator locations. Supplies will expand as the glass manufacturers create demand. To date there has been no meaningful market for the large volume of three color mixed cullet generated by current practices in the collection and disposal of solid waste. As a result, the volume of this material is approaching 50% of all post consumer recycled glass produced each day by material recovery facilities (MRF’s) and beneficiators. This material remains as a costly by-product of the production of post consumer single color cullet.
Mixed color cullet on a typical MRF processing line. Up to 50 percent ends up in a landfill instead of being used to make new glass.
The MRF’s and beneficiators, seeking to avoid costly landfill disposal of this large percentage of post consumer recycled glass, have turned to low value, limited commercial uses for this material such as road bed aggregate or landfill cover. Often, delivery costs exceed income produced by such means of disposal. Much of this material is currently stockpiled where land is available in order to avoid costly landfill disposal. The MRFs and beneficiators have employed manual color sorting and capital-intensive optical sorting equipment to positive sort clear (flint) and amber glass particles out of the 3-color mix cullet for sale as single color cullet (SCC.) This approach has resulted in expensive SCC and waste stream of 3 mix cullet still approximating 50% of all recycled glass, a tremendous waste of a usable resource.
By redeploying existing optical sorting equipment from color separation to contaminant removal from the 3 color mix cullet to produce C3MC™ cullet, glass beneficiators will be able to achieve a major increase in usable cullet produced from the recycled stream, approaching 80-85%, and, in turn, greatly reduce the cost of by- product disposal currently carried in the cost per ton of the product. This, in turn, will dramatically increase glass recycling.
Cullet Quality
Specifications
The quality of the C3MC™ cullet shall meet or exceed the requirements of the glass manufacturer. At a minimum, the categories that shall be specified include the following:
List of Attributes and contaminants for C3MC™ cullet
The technology required to meet glass plant quality standards and produce C3MC™ cullet has existed for several years, but has not been used to clean up mixed cullet. In 2003, GMG conducted a full-scale test of its technology at GGI, Millville, NJ. One hundred (100) tons of C3MC™ cullet was produced at a commercial CRA beneficiating facility using current optical sorting technology. The results demonstrated the ability of these systems to produce the specified quality of C3MC™ cullet.
Consistent Quality from all Beneficiators
C3MC™ cullet is a uniform and consistent product that will not exhibit significant color variations over reasonable manufacturing time periods. The large daily volumes of raw source material, post consumer cullet, do not vary significantly from month to month. Seasonal changes phase in and phase out with minor weekly changes in the color mix. These changes, and even more radical changes, are easily measured and compensated for during batch preparation using the GMG Batch Reformulation Software System.
Glass Chemistry
The C3MC™ cullet product will be consistent with good glass making practice and can be readily combined with standard batch materials to meet glass chemical targets. Minor additives used to maintain color balance determined by the GMG BFS are common additives familiar to the glass industry and which are readily combined with traditional batch mixtures to produce high quality glass.
