Energy recovery from vinery waste: Dust explosion issues

The concern about global warming issues and their consequences is more relevant than ever, and the H2020 objectives promoted by the EU are oriented towards generating climate actions and sustainable development. The energy sector constitutes a difficult challenge as it plays a key role in the global warming impact. Its decarbonization is a crucial factor, and significant efforts are needed to find efficient alternatives to fossil fuels in heating/electricity generation. The biomass energy industry could have a contribution to make in the shift to renewable sources; the quest for a suitable material is basically focused on the energy amount that it stores, its availability, logistical considerations, and safety issues. This work deals with the characterization of a wine-waste dust sample, in terms of its chemical composition, fire behavior, and explosion violence. This material could be efficiently used in energy generation (via direct burning as pellets), but scarce information is present in terms of the fire and explosion hazards when it is pulverized. In the following, the material is analyzed through different techniques in order to clearly understand its ignition sensitivity and fire effects; accelerating aging treatment is also used to simulate the sample storage life and determine the ways in which this affects its flammability and likelihood of explosion

Biomass from winery waste: Evaluation of dust explosion hazards

Food and drink supply chains have significant environmental impacts due to their use of resources, emissions, and waste production. An efficient method to reduce this impact is the valorisation of biomass waste through energy recovery by using it as a source of heat. The European energy system faces several fundamental challenges being currently the largest emitter of greenhouse gases due to its large dependence on fossil fuels (mostly natural gas). Therefore, the energy sector's decarbonization will play a central role in achieving a climateneutral economy in Europe. Identifying the suitable material for biofuel is basically focused on the amount of energy that the material stores, availability, and logistic considerations. Sawdust and wood chips have been extensively used as biofuel in recent years, but other promising raw and waste materials could be adopted (with the positive effect of reducing the impact on forestry soil and the food chain). Novel materials bring consequently novel challenges, also regarding their safe use. As an example, a relevant waste flow is produced from wine manufacturing. A solid with high moisture content is obtained from grapes pressing, and it could be reused to produce distillates. The obtained exhausted pomace could be considered among the materials potentially involved in energy recovery. It is also carrying dust explosion hazard, as solid residues could be present in the form of coarse and fine powders. In this work, grape pomace is examined: its explosion safety-related properties are evaluated to define the severity of events in which this material could be ignited. Minimum Ignition Energy (MIE), explosion pressure peak (Pmax), deflagration severity index (KSt), autoignition temperature (MIT), and Volatile Point (VP) are measured according to standard procedures. This material's thermal susceptibility and ignition sensitivity are studied and compared with biomasses from different sources (ligneo-cellulosic and herbaceous)

Issues of “Standard” explosion tests for non-spherical dusts

Measurements of the flammability and explosion parameters for non-spherical dusts are performed according to standard procedures in standard explosion equipment developed and tested for spherical dusts. Studies have shown that the standard procedures and equipment applied to spherical particles suffer from many issues: control of the turbulence level, non-uniform dust dispersion, and particle fragmentation due to the injection system. The applicability of the standard procedures and equipment to non-spherical particles is still an open issue. In this work, we have investigated, via CFD simulations, the distribution of turbulence and dust concentration in the standard 20 l spherical vessel for non-spherical particles. Results have shown that a higher turbulence level and a higher amount of dust actually fed into the vessel are reached with respect to spherical particles

Political economy of renewable resource federalism

Author Posting. © Ecological Society of America, 2021. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 00 (2021): e2276, doi:10.1002/eap.2276.The authority to manage natural capital often follows political boundaries rather than ecological. This mismatch can lead to unsustainable outcomes, as spillovers from one management area to the next may create adverse incentives for local decision making, even within a single country. At the same time, one‐size‐fits‐all approaches of federal (centralized) authority can fail to respond to state (decentralized) heterogeneity and can result in inefficient economic or detrimental ecological outcomes. Here we utilize a spatially explicit coupled natural–human system model of a fishery to illuminate trade‐offs posed by the choice between federal vs. state control of renewable resources. We solve for the dynamics of fishing effort and fish stocks that result from different approaches to federal management that vary in terms of flexibility. Adapting numerical methods from engineering, we also solve for the open‐loop Nash equilibrium characterizing state management outcomes, where each state anticipates and responds to the choices of the others. We consider traditional federalism questions (state vs. federal management) as well as more contemporary questions about the economic and ecological impacts of shifting regulatory authority from one level to another. The key mechanisms behind the trade‐offs include whether differences in local conditions are driven by biological or economic mechanisms; degree of flexibility embedded in the federal management; the spatial and temporal distribution of economic returns across states; and the status‐quo management type. While simple rules‐of‐thumb are elusive, our analysis reveals the complex political economy dimensions of renewable resource federalism.This work was partially supported through the Ecological Federalism working group of the National Institute for Mathematical and Biological Synthesis, an Institute sponsored by the National Science Foundation through NSF Award (No. DBI‐1300426), with additional support from the Howard H. Baker Jr. Center for Public Policy and The University of Tennessee, Knoxville. M. G. Neubert acknowledges support from the U.S. National Science Foundation (DEB‐1558904) and from the J. Seward Johnson Endowment in support of the Woods Hole Oceanographic Institution’s Marine Policy Center. We would like to thank seminar participants at Oregon State University, Nature Policy Lab at U.C. Davis, and the 2019 Association of Environmental and Resource Economists Summer Conference for valuable comments and suggestions on earlier versions of this research

Reframing Optimal Control Problems for Infectious Disease Management in Low-Income Countries

Optimal control theory can be a useful tool to identify the best strategies for the management of infectious diseases. In most of the applications to disease control with ordinary differential equations, the objective functional to be optimized is formulated in monetary terms as the sum of intervention costs and the cost associated with the burden of disease. We present alternate formulations that express epidemiological outcomes via health metrics and reframe the problem to include features such as budget constraints and epidemiological targets. These alternate formulations are illustrated with a compartmental cholera model. The alternate formulations permit us to better explore the sensitivity of the optimal control solutions to changes in available budget or the desired epidemiological target. We also discuss some limitations of comprehensive cost assessment in epidemiology

Genes as Tags: The Tax Implications of Widely Available Genetic Information

This paper examines how progress in genetics\u27 specifically, the proliferation of knowledge about the human genome\u27 may influence the feasibility and desirability of a tax that is based on individual human endowments or ability. The paper explores various forms that such a genetic endowment tax-and-transfer regime might take and identifies some of the benefits and costs of such a regime. The authors take no position on whether a genetic endowment tax would be desirable or not. However, one contribution of the paper is to observe that current law in the U.S., which restricts the use of genetic information by insurers and employers, is equivalent to a form of genetic endowment tax. The paper also notes that, in the absence of a government-mandated transfer policy with respect to genetic endowments, private insurance markets may arise to fill the gap, allowing individuals to purchase insurance against the possibility of a bad genetic draw