BHZ Trial: Bio-Based Rejuvenator Enables High Performance, High Percentage, Recycled Asphalt for Roads

Almere, The Netherlands, June 1st, 2017

An in-plant and road trial, conducted by Swiss building materials company BHZ Baustoff Verwaltungs Ag, found that using SYLVAROAD™ RP1000 Performance Additive enables a high-performing mix containing 60 percent recycled asphalt material. SYLVAROAD, a bio-based rejuvenator of recycled asphalt (RA) made by Arizona Chemical, a subsidiary of Kraton Corporation, has demonstrated that the product can enable a high-performing asphalt mix containing 60 percent of recycled material while using a standard 70/100 binder and thus avoiding the soft bitumen.

The aim of this trial was to test the effectiveness of Arizona Chemical’s SYLVAROAD™ RP1000 Performance Additive as a replacement for soft binder. This additive can also be used to increase the amount of RA used in mixes, while equaling or bettering non-RA mix performance characteristics.

Produced at BHZ’s asphalt plant near Neftenbach, Switzerland and applied on a road stretch nearby, the company prepared a mix using RA with a softening point of 65°C. A reference mix and a mix with additive were produced with:

1. The company’s standard reference formula of 60 percent RA and a soft binder (PEN 250/330) with a final binder specification of PEN 70/100.
2. 60 percent RA, the standard binder (PEN 70/100) and 5 percent SYLVAROAD added on the RA.

The trial results showed that the mix with SYLVAROAD performed well, with good workability, compactibility. BHZ was able to achieve the required specifications without use of a soft binder. A small-scale trial using 100 percent RA and SYLVAROAD is also underway.

“The results of this SYLVAROAD trial bring us closer to our goal of increasing the amount of asphalt we can successfully recycle for road construction in Switzerland,” said Mr. Bernard Kunz, Director of BHZ. “We also now have a viable option to replace soft binder with a bio-based rejuvenator.”

The SYLVAROAD rejuvenator was sprayed directly onto the RA on a conveyor belt that led to a parallel drum for heating and warming. This process is more efficient than adding the rejuvenator directly to the drum, and results in a consistent mix. At the drum stage the RA softening point was reduced to 58°C. After further mixing and the addition of virgin 70/100 binder, the final softening point was 57°C. This was two degrees lower than the final reading of the reference mix (59°C).

“SYLVAROAD softens binders by interacting with them at the molecular level,” said Maria Di Nolfo, business unit manager, roads and construction at Arizona Chemical. “This enables substantially more asphalt to be recycled, thereby furthering achievement of circular economy goals.”

In addition to the Swiss trial, within the last year a bike lane was constructed made of 100 percent RA enabled by the SYLVAROAD rejuvenator in Rotterdam, The Netherlands. Through a partnership with FM Conway and Transport for London, a trial began on a three-lane UK highway composed entirely of 50 percent RA containing SYLVAROAD. And in Niort, France, a project with Eurovia also explored the product’s effectiveness with extremely hard binder, which normally could only be recycled for a road’s unbound sub-base layers.

About Kraton Corporation
Kraton Corporation (NYSE “KRA”) is a leading global producer of styrenic block copolymers, specialty polymers and high-value performance products derived from pine wood pulping co-products. Kraton’s polymers are used in a wide range of applications, including adhesives, coatings, consumer and personal care products, sealants and lubricants, and medical, packaging, automotive, paving, roofing and footwear products. As the largest global provider in the pine chemicals industry, the company’s pine-based specialty products are sold into adhesive, road and construction and tire markets, and it produces and sells a broad range of chemical intermediates into markets that include fuel additives, oilfield chemicals, coatings, metalworking fluids and lubricants, inks, flavors and fragrances and mining. Kraton offers its products to a diverse customer base in over 70 countries worldwide. KRATON, the KRATON logo, and SYLVAROAD are trademarks of Kraton Corporation, or its subsidiaries or affiliates, in one or more, but not all countries.