Fugitive emissions in chemical processes: The assessment and prevention based on inherent and add-on approaches

Fugitive emissions are among the major concerns of industrial process releases. The emissions cause problem to various aspects including the environment, health, and economic. Early evaluation of process hazards is beneficial because process can be made inherently benign at lower cost. This paper discusses two important aspects of fugitive emissions assessment during process design – the quantification and the prevention strategies.For the quantification part, three methods are presented for fugitive emissions estimation during the process design. They are tailored to data available in simple process flow diagram (PFD), detailed PFD, and piping & instrumentation diagram (PID). Such methods are needed as early emissions estimation allows production routes and process designs with lower emissions to be selected. The fugitive emissions estimation and methods to abatement are demonstrated on a benzene process case study. Valves are found to be the major emission source with 50% of fugitive emissions of process area in a base case of petrochemical process, in which no fugitive emission reductions are yet made. Pumps without mechanical seals come second with 30% and flanges with 8% of emissions. Inherently safer design keywords can be applied to prevent fugitive emissions in the process plants. Substitution is the most applicable keyword in fugitive emission reduction of existing plants.The emission rate calculations together with estimation of health risk give a sound background for the decision making on elimination of emissions at source through equipment and piping changes. The case study presented reveals that by substituting emission prone components by inherently low-leaking ones, the plant emissions can be reduced over 90% in practice. This is created mainly by replacing rising stem valves with ball valves, installing double mechanical pump seals or hermetic pumps and making changes in sampling and relief systems. Ideally by also changing flanges to welded connections, which is not viable for various reasons, the emissions could be reduced nearly to zero.     

When all life counts in conservation

Conservation science involves the collection and analysis of data. These scientific practices emerge from values that shape who and what is counted. Currently, conservation data are filtered through a value system that considers native life the only appropriate subject of conservation concern. We examined how trends in species richness, distribution, and threats change when all wildlife count by adding so-called non-native and feral populations to the International Union for Conservation of Nature Red List and local species richness assessments. We focused on vertebrate populations with founding members taken into and out of Australia by humans (i.e., migrants). We identified 87 immigrant and 47 emigrant vertebrate species. Formal conservation accounts underestimated global ranges by an average of 30% for immigrants and 7% for emigrants; immigrations surpassed extinctions in Australia by 52 species; migrants were disproportionately threatened (33% of immigrants and 29% of emigrants were threatened or decreasing in their native ranges); and incorporating migrant populations into risk assessments reduced global threat statuses for 15 of 18 species. Australian policies defined most immigrants as pests (76%), and conservation was the most commonly stated motivation for targeting these species in killing programs (37% of immigrants). Inclusive biodiversity data open space for dialogue on the ethical and empirical assumptions underlying conservation science.     

Epidemiological assessment of antibiotic residues in dairy farm milk and farm waste and water in northern India

Environmental Science and Pollution Research - Antibiotics are frequently used in the dairy sector for prophylactic uses along with therapeutic purposes. Throughout the globe, antibiotic resistance...     

The moral residue of conservation

Should conservationists use lethal management to control introduced wildlife populations? Should they kill individual animals to protect endangered species? Are trade-offs that prioritize some values at the expense of others morally appropriate? These sorts of ethical questions are common in conservation. In debating such questions, conservationists often seem to presume 1 of 2 possible answers: the act in question is right or it is wrong. But morality in conservation is considerably more complex than this simple binary suggests. A robust conservation ethic requires a vocabulary that gives voice to the uncertainty and unease that arise when what seems to be the best available course of action also seems to involve a measure of wrongdoing. The philosophical literature on moral residue and moral dilemmas supplies this vocabulary. Moral dilemmas arise when one must neglect certain moral requirements to fulfill others. Under such circumstances, even the best possible decision leaves a moral residue, which is experienced emotionally as some form of grief. Examples of conservation scenarios that leave a moral residue include management of introduced rabbits in Australia, trophy hunting in Africa, and forest management trade-offs in the Pacific Northwest. Moral residue is integral to the moral experience of conservationists today, and grief is an appropriate response to many decisions conservationists must make. Article impact statement: Defensible conservation decisions may neglect moral requirements, leaving a moral residue; conservationists should respond with grief.     

Incorporating evolutionary processes into population viability models

We examined how ecological and evolutionary (eco‐evo) processes in population dynamics could be better integrated into population viability analysis (PVA). Complementary advances in computation and population genomics can be combined into an eco‐evo PVA to offer powerful new approaches to understand the influence of evolutionary processes on population persistence. We developed the mechanistic basis of an eco‐evo PVA using individual‐based models with individual‐level genotype tracking and dynamic genotype–phenotype mapping to model emergent population‐level effects, such as local adaptation and genetic rescue. We then outline how genomics can allow or improve parameter estimation for PVA models by providing genotypic information at large numbers of loci for neutral and functional genome regions. As climate change and other threatening processes increase in rate and scale, eco‐evo PVAs will become essential research tools to evaluate the effects of adaptive potential, evolutionary rescue, and locally adapted traits on persistence.     

A review of selection‐based tests of abiotic surrogates for species representation

Because conservation planners typically lack data on where species occur, environmental surrogates—including geophysical settings and climate types—have been used to prioritize sites within a planning area. We reviewed 622 evaluations of the effectiveness of abiotic surrogates in representing species in 19 study areas. Sites selected using abiotic surrogates represented more species than an equal number of randomly selected sites in 43% of tests (55% for plants) and on average improved on random selection of sites by about 8% (21% for plants). Environmental diversity (ED) (42% median improvement on random selection) and biotically informed clusters showed promising results and merit additional testing. We suggest 4 ways to improve performance of abiotic surrogates. First, analysts should consider a broad spectrum of candidate variables to define surrogates, including rarely used variables related to geographic separation, distance from coast, hydrology, and within‐site abiotic diversity. Second, abiotic surrogates should be defined at fine thematic resolution. Third, sites (the landscape units prioritized within a planning area) should be small enough to ensure that surrogates reflect species’ environments and to produce prioritizations that match the spatial resolution of conservation decisions. Fourth, if species inventories are available for some planning units, planners should define surrogates based on the abiotic variables that most influence species turnover in the planning area. Although species inventories increase the cost of using abiotic surrogates, a modest number of inventories could provide the data needed to select variables and evaluate surrogates. Additional tests of nonclimate abiotic surrogates are needed to evaluate the utility of conserving nature's stage as a strategy for conservation planning in the face of climate change.