System for Processing of Reclaimed Asphalt Planings (RAP) for High Percentage Incorporation of RAP in new lay road surfaces (Infrarap)

目前，从道路上取出的沥青被储存起来，供以后在一家沥青厂用作新的热拌沥青(HMA)的集料。这种再生材料通常被称为RAP再生或再生沥青刨花板，被粉碎到一致的级配并添加到HMA搅拌过程中。沥青由95%的集料和5%的沥青组成，两者都是宝贵的资源，蕴含的能量和二氧化碳排放量都很高。目前已有几种沥青就地和非就地再生技术，其中最常见的是采用绕过干燥滚筒的冷进料的RAP。由于高水分含量，非常低的体积(~20%)被重复使用，能源成本显著高，因为原始集料必须被加热到200-300℃。此外，老化的沥青粘结剂会被干燥原始集料所需的高温损坏，变得容易紫外线降解，容易早期石材损失和开裂。Infrarap项目旨在开发一种处理RAP的系统，以便可以将更高比例的RAP添加到铺路材料中，特别是磨损层中。该系统将包括适应性加热、混合和输送系统，这些系统将在最佳低温下将RAP送入提升料斗，或通过使用高效再生器的静态搅拌站或移动搅拌站的转向器直接送入搅拌机-给料槽，这将允许高比例的RAP在低温下回收到沥青混合料中。显然，市场需要一种独立的方法来加热和直接将RAP送入混合设备的PUG-MILL中，这种方法绕过了干燥滚筒，并消除了所有有害的问题，包括烧焦的RAP和堵塞过滤器和筛网。

Currently, asphalt removed from a road is stockpiled for later use as aggregate for new hotmix asphalt (HMA) at an asphalt plant. This reclaimed material, commonly known as RAP –recycled or reclaimed asphalt planings, is crushed to a consistent gradation and added to theHMA mixing process. Asphalt consists of 95% aggregate and 5% bitumen, both of which arevaluable resources with high embedded energy and CO2 footprint.Several in-situ and ex-situ recycling techniques exist for asphalt recycling the most commonof which introduces RAP using a cold feed which bypasses the drying drum. Due to the highmoisture content, very low volumes (~20%) are re-used at a significantly high energy costbecause the virgin aggregate must be heated to 200-300 deg C. There are also significantissues with the quality of the final product as the aged bitumen binder is damaged by the hightemperature needed to dry the virgin aggregate and becomes susceptible to UV degradationand is rendered liable to early stone loss and cracking.The Infrarap project aims to develop a system for processing RAP so that higher percentagescan be incorporated into paving materials and especially into the wearing course layer. Thesystem will comprise adaptable heating, mixing and conveying systems which will feed RAPat an optimum low temperature into elevating skips or direct to a mixer-feed chute via aconveyor of a static mixing plant or a mobile mixing plant using an efficient rejuvenatorwhich will allow high percentages of RAP to be recycled into asphalt mixes at lowtemperatures.The development follows some preliminary investigations into current methods ofincorporating RAP into mixes, including alternative systems. There is a clear market need foran independent method of heating and directly feeding RAP into the pug-mills of mixingplants that bypasses a drying drum and obviates all adverse issues with scorching RAP andblocking filters and screens.