This Small Business Innovation Research Phase I project will study the feasibility of recycling used disposable diapers into green roof materials using simple processing technologies. Disposable diapers are the most disposed household product in North America, accounting for about four million tons solid waste annually. Currently, only a negligible percentage of them are recycled. Conventional recycling separates and purifies each component of a waste material for subsequent applications, where higher purity is associated with higher value. For the after-consumer disposable diapers, however, it is not profitable to recycle in this manner because of their complexity. The proposed approach is to process the diapers directly into modular green roof materials without completely separating the individual components. The proposed green roof product is lightweight, easy-to-use and drought-resistant, with high water uptake, long retention time, and a low maintenance cost compared to competing products. The Phase I technology development will target low-cost production and environmentally benign processing.
The broader impact/commercial potential of this project will be a product which will accelerate the development of the green roof market in U.S. Currently, the domestic green roof market is limited, with a much smaller size than the European market. The lack of domestic recognition and the high cost of products are the primary reasons for this. Commercially available products are all somewhat similar in philosophy, in that some kind of container is filled with growth media and then mounted on an existing roof. The products resulting from this project will be low cost and have low maintenance requirements. The associated economic and social benefits of this project will include reductions in energy consumption, greenhouse gas emissions, solid waste, and a decrease in the urban heat island effect, as well as habitat and biodiversity preservation, and stormwater retention. Broader market applications, such as horticultural lightweight growth medium, erosion control products, and growth medium for arid/semiarid areas, will also be considered.
National Science Foundation Award 1046780 This Small Business Innovation Research Phase I project studied the feasibility of converting a negative environmental impact (solid waste) into a positive environmental impact (green roof) using simple and environmentally benign processing technologies. The Phase I project has focused on the development of technologies, preliminary product design and evaluation. The results from this project showed the feasibility to produce modular green roof products from recycled disposable diapers. The proposed product has two most unique features: super drought resistance and lightweight. The growth medium in the modular green roof trays can absorb more waters and maintain a lower weight than commercially available green roof growth media. The drought resistant feature can greatly reduce water usage and irrigation frequency. The lightweight feature reduces the requirements for infrastructure and makes this product suitable more broadly for existing roofs. The present study also shows the feasibility to perform 100% recycling of disposed diapers using the proposed economical recycling and manufacturing processes. The broader impact/commercial potential of this project is to accelerate the development of green roof market in U.S. The products resulted from a completion of this program are featured with low cost and low maintenance requirements. The associated economic and social benefits include reductions in energy consumption, greenhouse gas emission, solid waste, and the urban heat island effect, as well as habitat and biodiversity preservation, stormwater retention, and job creation. Zynnovation's product can also help contribute towards Leadership in Energy & Environmental Design (LEED) certification in the materials & resources category, especially the recycled content, regional materials, and rapidly renewable materials subcategories. Ordinary materials used in the current green roof market do not necessarily qualify for these categories.
