Iddo K. Wernick

Resource recovery from used rubber tires

Abstract Including car, truck, bus, and airplane tires, 266 million tires were scrapped in the US in 1996 ( Scrap Tire Management Council (STMC), 1997. ). More than three-quarters of these tires were used as fuel, recycled for material applications, or exported. The remainder accumulates in junkyards or landfills where they pose a fire hazard and provide a breeding ground for disease carrying rodents and insects. Using information on scrap tire composition and the current markets using them, we examine the technologies used to recover their value either for energy or as rubber. As the majority of scrap tires are used as fuel, we calculate their life cycle energy budget considering both the energy consumed for tire production and the energy recovered from their use as fuel. Based on our findings, we draw some preliminary conclusions on how to maximize value recovery from this ubiquitous artifact of industrial societies.

Modeling materials flow of waste concrete from construction and demolition wastes in Taiwan

Abstract Material flows of concrete from construction and demolition (CD (2) Around the year 2009, the national rate will more than triple to exceed the spike in C&D concrete waste generation that occurred after the Chi Chi earthquake 9/21/99, 8.5 MMT. (3) Aside from pilot-scale development of waste concrete utilization technology, nationwide recycling rates remain negligible. Without resource recovery, the volume of C&D waste generation by 2009 is projected to occupy nearly 7% of all existing and planned domestic landfill capacity. A target is established to raise resource recovery rates for waste concrete to 50% by 2005 and a 100% nationwide recycling rate by 2009.

A National and International Analysis of Changing Forest Density

Like cities, forests grow by spreading out or by growing denser. Both inventories taken steadily by a single nation and other inventories gathered recently from many nations by the United Nations confirm the asynchronous effects of changing area and of density or volume per hectare. United States forests spread little after 1953, while growing density per hectare increased national volume and thus sequestered carbon. The 2010 United Nations appraisal of global forests during the briefer span of two decades after 1990 reveals a similar pattern: A slowing decline of area with growing volume means growing density in 68 nations encompassing 72% of reported global forest land and 68% of reported global carbon mass. To summarize, the nations were placed in 5 regions named for continents. During 1990–2010 national density grew unevenly, but nevertheless grew in all regions. Growing density was responsible for substantially increasing sequestered carbon in the European and North American regions, despite smaller changes in area. Density nudged upward in the African and South American regions as area loss outstripped the loss of carbon. For the Asian region, density grew in the first decade and fell slightly in the second as forest area expanded. The different courses of area and density disqualify area as a proxy for volume and carbon. Applying forestry methods traditionally used to measure timber volumes still offers a necessary route to measuring carbon stocks. With little expansion of forest area, managing for timber growth and density offered a way to increase carbon stocks.

National material metrics for industrial ecology

Abstract We present an assembly of metrics for monitoring environmental performance at the national level, based on the flow of materials through the US economy. To set the stage, we show a schematic rendering of national materials flows, identifying the most important flow components. We compare and contrast amounts of materials entering and exiting the economy, using weight as the common measure. Additionally, we relate physical data on materials consumption and disposal to monetary measures of national economic activity. Eight general classes and eighteen individual metrics comprise the set. For several, we provide quantitative examples. Our aim is to initiate a framework for assessing national materials use which helps prevent pollution, reduce waste and encourage efficient resource use.

Lightening the tread of population on the land: American examples.

The authors search the past century for principles and trends influencing land use in the United States and contemplate the future when Americans might number an additional 100 million. Examples from American cities counties and states suggest that land covered by the built environment increases less than in proportion to population. For example despite the rising use of paper relative to gross national product the declining use of lumber combined with improved forestry kept the area of forest land fairly steady as population rose. Similarly rising yields and changing tastes have countered the impact of rising population and wealth on crop-land area. All told a lightening tread of Americans on the land in the next century could spare for nature over 90 million hectares an area equal to 100 times the size of Yellowstone National Park. (SUMMARY IN FRE AND SPA) (EXCERPT)

Consuming materials: The American way

Abstract Sustaining the U.S. economy requires large inputs of materials, and their extraction, processing, and consumption affect the environment in many ways. In the United States, as in most industrialized countries, bulk materials consumption no longer runs in tanden with economic activity. Demand for raw materials in the richer countries has fallen well below the forecasts of decades ago, confounding predictions of dire shortage and reducing the projected income of countries that rely on mineral exports. Demographic shifts in the US and individual consumer preferences drive greater and more varied consumption. Saturated markets and technological advances offer promise for reduction. The success of large-scale materials recycling depends on the economics of secondary materials recovery and the suitability of secondary materials for reuse. Powerful social and demographic forces that draw more materials into the system will vie with technological innovations intended to limit inputs in shaping the future path of materials consumption in the United States.

Environmental Knowledge Management

dvances in the emerging field of knowledgemanagement, the intelligent processingand distribution of information, hold outthepos-sibility of integrating industrial ecology intostandard business practices. As network comput-ing has evolved to routinely provide users withuniversal access to data and applications, theproblem has become sifting through the hugevolume of information rather than havingaccess.Knowledge management (KM) has the goal ofproviding the right information to the right per-son at the right time. “Knowledge” here meansinformation placed in context and goes beyondelectronic artifacts to includethe knowledge that resides inpeople’s heads. The integrationof industrial ecology objectiveswith KM tools could give riseto environmental knowledgemanagement (EKM) systemsthat use knowledge to improvecorporate environmental per-formance by lowering the in-formation barrier that prevents organizationsfrom realizing environmental opportunities.Will EKM systems align industrial ecologywith market forces? Will market actors respondto the new knowledge? Will they bother to in-tegrate it and act? The challenge of replacing en-terprise business applications with ones that fullyintegrate environmental performance concernsremains formidable. Experience in North Amer-ica suggests that success occurs primarily in caseswhere environmental initiatives are consistentwith innovative, but already accepted, businessapplications. Identifying the areas where EKMcan integrate with existing enterprise businesssystems should guide EKM development andeventually lead to their broader integration inthe future. For instance, companies already usingactivity-based cost accounting methods can lev-erage their existing platform for sophisticateden-vironmental cost accounting. Those firms usingmetric-based management can extend this strat-egy to encompass resource productivity andwaste generation.In the context of a commercial enterprise,EKM systems can embed management-level de-cisions into standard business practice to realizesome practical industrial ecol-ogy innovations. EKM systemscan greatly reduce the searchcosts involved in finding envi-ronmental regulatory, techni-cal, and market information,for example, by integrating pro-curement systems with the ca-pability for federated searchesof environmentally benign sub-stitutes. As entire supply chains become digitized(see the discussion of product tags by Saar andThomas, this volume), EKM components can beintegrated withsupply-chainmanagementsystemsto monitor supplier environmental performanceratings, as well as the material composition ofproduct components. For capital-intensive envi-ronmental initiatives, such as upgrading afacility’senergy supply, EKM systems can consolidate theelectronic libraries and analytic applications nec-essary for evaluating the benefits and costs of al-ternative paths.Inevitably, industrial ecology relies on effec-tive communication within and between orga-nizations, be they buyers and sellers of industrialwastes or product design and marketing teams toimplement design for environment (DfE) initia-

Death and the human environment: the United States in the 20th century

Abstract Causes of death varied systematically in the United States during the 20th century as the human environment came under control. Infections became less deadly, while heart disease grew dominant, followed by cancer. Logistic models of growth and multi-species competition in which the causes of death are the competitors describe precisely the evolutionary success of the killers. We show the dossiers of typhoid, diphtheria, cholera, tuberculosis, pneumonia/influenza, heart disease, cancer, and AIDS. Improvements in water and air supply and other aspects of the environment provided cardinal defenses against infection. We project cancer will overtake heart disease as the leading cause of death about 2015, and infections may gradually regain their deadly edge.

Dematerialization and secondary materials recovery in the U.S.

Complexity in individual materials as well as the diversity of materials used in industrial and consumer products leads to problems both in isolating material components and retaining the value embedded in material goods, posing problems for effective materials recovery. Secondary materials processors must respond to contemporary challenges arising from materials complexity and diversity if they are to serve their proper function in minimizing the environmental disturbances associated with expanding material consumption.

Robotic Brachytherapy and Sublobar Resection for T1 Non-Small Cell Lung Cancer in High-Risk Patients

BACKGROUND Sublobar lung resection and brachytherapy seed placement is gaining acceptance for T1 non-small cell lung cancer (NSCLC) in select patients with comorbidities precluding lobectomy. Our institution first reported utilization of the da Vinci system for robotic brachytherapy developed experimentally in swine and applied to high-risk patients 5 years ago. We now report seed dosimetrics and midterm follow-up. METHODS Eleven high-risk patients with stage IA NSCLC who were not candidates for conventional lobectomy underwent limited resection of 12 primary tumors. To reduce locoregional recurrence, (125)I brachytherapy seeds were robotically sutured intracorporeally over resection margins to deliver 14,400 cGy 1 cm from the implant plane. Patients were followed with dosimetric computed tomography scans at 30 +/- 16 days. Survival and sites of recurrence were documented. RESULTS Resected tumor size averaged 1.48 +/- 0.38 cm (range, 1.1 to 2.1 cm). Perioperative mortality was 0% and recurrence was 9% (1 of 11 [margin recurrence at 6 months with resultant mortality at 1 year]). Follow-up duration was 31.82 +/- 17.35 months. Dosimetrics confirmed 14,400 cGy delivery using 24.21 +/- 4.6 (125)I seeds (range, 17 to 30 seeds) over a planning target volume of 10.29 +/- 2.39 cc(3). Overall, 84.1% of the planning target volume was covered by 100% of the prescription dose (V100), and 88.2% was covered by 87% of the prescription dose (V87), comparable to open dosimetric data at our institution. Follow-up imaging confirmed seed stability in all patients. CONCLUSIONS Robotic (125)I brachytherapy seed placement is a feasible adjuvant procedure to reduce the incidence of recurrence after sublobar resection in medically compromised patients. Tailored robotic seed placement delivers an exact dosing regimen in a minimally invasive fashion with equivalent precision to open surgery.