Steady-state process modeling of oil shale retorting using simulation software Aspen Plus is progressed. More components are included to allow all significant mineral and organic reactions to be represented. Secondary thermal cracking reactions are added to predict effects on product distribution and composition. Stoichiometric reactor blocks are replaced with kinetic reactor block models that predict the extents of conversions as a function of temperature, composition, and volume. As an example, a model is developed for the retorting of Green River oil shale in the Union B process. The effect of key operating temperatures on the quantity of lost oil yield due to thermal cracking in the hot recycle gas is predicted.

An oil shale surface retorting technology is commercialized by building and operating a series of progressively larger plants. Capital and operating costs depend on the size of the plant. The rate that a plant achieves its annualized design capacity is assumed to depend on the relative size of a prior plant of the same technology and is based on the experience of mineral processing plants in general. Development strategies of a com- mercial project are compared using a simple real options model. The economic analysis illustrates that for a particular project there is an optimum num- ber of intermediate plants that maximizes the weighted net present value of the project. An unproven technology must also promise a significant advantage over a demonstrated technology to justify additional development time, costs and risk.

Due to the peak production of conventional crude oil and the higher oil price in the last cou- ple of years, shale oil is a possible alternative source of oil in the future. The global shale oil resources could be trillions of barrels but must first be extracted by retorting the oil shale. Current retorting technologies generate and emit CO2 similar to coal-fired power plants. New shale oil projects may need to consider reducing CO2 emissions to meet future government environmental regulations. This paper proposes a novel Zero Emission Oil Shale Process (ZEOSP). The concept is to produce shale oil, energy (electricity, steam) and high purity CO2 from oil shale with near zero emission of CO2 and other atmospheric pollutants. A mixture of high purity oxygen and CO2 from flue gas is used in the spent shale combustion instead of air and thus achieves a concentrated CO2 flue gas which can be captured and stored. Current existing solid heat carrier oil shale processes and vertical gas heat carrier processes can be upgraded with the ZEOSP concept. The conceptual process design and operation performance are evaluated by using an oil shale process simulation package on the energy efficiency improvement and sequestration of CO2 without affecting shale oil yield. Shale oil production cost is analyzed to provide an insight on the economic performance of the tech- nology.

Differential scanning calorimetry (DSC) and simultaneous thermogravimetry/differential thermal analysis (TG/DTA) were used for the determination of reaction heats and mass losses, respectively, of oil shales for the temperature range of the drying/preheating process and retorting. The samples originated from the Stuart, Condor, Nagoorin, Lowmead and Duaringe Tertiary oil shale deposits in southeastern Queensland, Australia. The results showed that the enthalpy associated with retorting ranged between 68 J g−1 and 194 J g−1. The mass losses associated with drying/preheating and retorting were found to range between 1.0% and 6.0%, and 5.4% and 30.9%, respectively. A correlation between retort enthalpy and siderite and clay contents of the oil shales was established. The Duaringa shale sample was found to behave differently from the other shales.

Coyote (Canis latrans) attacks on humans, once thought to be rare, have increased in frequency over the past decade. In Arizona, the number of wildlife human encounters has increased as our urban environments have expanded into the coyote's natural environment. Coyotes have learned to utilize drip irrigation, pet food, household refuse, and pets as prey. The problem of potential coyote attacks is magnified when people intentionally feed coyotes. In some situations, coyotes have begun to act aggressively toward humans, chasing joggers/walkers, confronting people walking their dogs, and stalking small children. People who live in areas where coyotes are present need to understand the potential hazard that these animals pose to their safety. To effectively manage coyotes in an urban environment, a variety of control methods must be implemented since no single method is effective in every situation. In 2006, the State of Arizona passed a new law that makes it illegal to feed wild animals (except birds and tree squirrels) in Pima and Maricopa Counties to help alleviate issues with wildlife. Unfortunately, the word has not gotten out, and people continue to feed wildlife. The Arizona Game and Fish Department had not reported any bites in the Tucson, Arizona area during the past 3 years, but this streak ended in November 2006 when a coyote or coyotes attacked and injured 8 people in Green Valley, Arizona, during a 13-day period. WS Wildlife Specialists removed 7 coyotes from the area, and the coyote attacks on humans ceased. This paper reviews urban coyote issues in Arizona and describes the numerous bite cases in Green Valley.