Processing Of Fossil Fuels Research Articles

Perovskite Catalysts for Biomass Valorization

Biomass is a widely used renewable energy source, whose uptake is growing due to concerns about the impact of anthropogenic fossil fuel combustion on climate change. Waste biomass-derived fuels and chemicals offer a partial solution to reducing global reliance on fossil fuels in pursuit of Net Zero 2050 CO2 emissions, in concert with environmental, health, and economic benefits. Biorefineries aim to convert biomass resources such as forestry and agricultural waste into diverse product streams, akin to the processing of nonrenewable fossil fuels by petrochemical refineries. However, realizing this ambition requires design of hydrothermally stable catalysts with tunable redox properties and acid–base character to promote molecular deoxygenation or the interconversion of oxygen functionalities. Perovskite oxides of general formula ABO3 (where A = rare or alkaline earth cations and B = transition metal cations) exhibit structural flexibility and diverse surface chemistry; ∼90% of all metals can be introduced to perovskite oxides. Here, we review recent developments in the use of perovskite oxide catalysts for biomass valorization, focusing on structure–reactivity relationships in hydroprocessing, oxidation, steam reforming, and acid–base reactions. Prospects and challenges for the broader application of perovskite oxide catalysts to biomass valorization are also highlighted.

Introducing the total efficiency to address challenges of the 21st century

The evaluation and comparative analyses of energy conversion technologies are carried out with well-established concepts, like the concept of efficiency. Today, however, new technologies based on renewable energy sources challenge conventional approaches. Accounting for fuel diversity and other inequalities can ensure that comparative analyses result in trustworthy results. This paper aims to address this issue by updating conventional efficiency for more accurate comparative evaluations of fossil fuel energy systems. Specifically, the concept of total efficiency is introduced to account for extraction, processing and transportation of fossil fuels, aspects that are not currently considered in the conventional definition of efficiency. The total efficiency is determined by studying the environmental impacts of these processes and quantifying their energy requirements in terms of additional fossil fuel use. Two case studies in Spain are presented to demonstrate the impact of using the developed method on efficiency estimates. The total efficiency is found to be lower than the convectional efficiency by 21–25% to up to 41%, in the most unfavorable cases. This shows the significant impact of the preparation steps of fossil fuels and represents a fairer comparison between fossil fuels and renewable conversion processes.

Selective Hydrogenation of Naphthalene to Decalin Over Surface‐Engineered α‐MoC Based on Synergy between Pd Doping and Mo Vacancy Generation

AbstractAlthough the hydrogenation of aromatics is important for the processing of fossil fuels and biofuels, it typically requires costly (e.g., noble metal‐based) catalysts and exhibits unsatisfactory selectivity. Herein, flake‐like nanocrystalline molybdenum carbide (α‐MoC) is surface‐engineered via Pd doping, and the synergy between the in‐situ generated Mo vacancies and doped Pd species is shown to promote the selective hydrogenation of naphthalene to decalin. Experimental and theoretical evidence reveal that this enhanced performance is due to the optimization of naphthalene adsorption energy and the establishment of a unique surface structure due to (i) surface environment modulation, (ii) the adjustment of electron density around Mo atoms, and (iii) the change in the strength of Mo‐H bonding caused by d‐band center optimization. Benefiting from the unique surface structure, the obtained optimum 0.5% Pd‐α‐MoC catalyst exhibits excellent performance. The developed strategy is successfully used to fabricate other noble metal (Pt, Ru)‐doped α‐MoC catalysts, thus holding promise as a universal method for the rational design of high‐performance metal carbide‐based hydrogenation catalysts.

Solid Fossil Fuels as a Source of Trace Elements

Processes for the concentration of valuable elements in solid fossil fuels and methods for their determination in the composition of coal and oil shale are presented. Various methods of extracting valuable elements (for example, germanium) from fossil raw materials and their conversion products and an ecological aspect of the influence of the toxic compounds of trace elements formed upon the extraction and processing of fossil fuels are considered.

The influence of the investment factor on the transformation of the global energy market

The object of the study is the transformation of the world energy market under the influence of investment. The study of the impact of investments on the transformation of the world energy market was carried out in terms of market, structural, and organizational parameters in the following areas:– the growing role of renewable sources in the world energy balance;– liberalization of sectoral energy markets;– wide application of information technologies, including the introduction of Smart Grid at various levels.The main disadvantages are the inability to analyze the transformation processes in all sectors of energy at the global level.Such general scientific and special methods as methods of analysis and synthesis, method of comparative analysis, graphic and statistical methods were used in the research.The paper shows that at the present stage the main prerequisite for investment has been the COVD-19 pandemic and pre-crisis expectations. This has led to a sharp decline in global investment in all energy sectors (both in aggregate energy supply and in end-use) and in research and development. In terms of industry, investments in oil and oil products (by all organizational forms of companies) and coal decreased the most. Investment in electricity and electricity networks exceeds investment in mining and processing of fossil fuels. The main factors holding back international investment in renewable energy are:– relatively lower economic and energy return on investment (EROI);– the high cost of connection to power systems;– local component requirements and other protectionist requirements;– discrediting by global oil and gas corporations about the danger of economic downturn and job cuts, etc.In the regional structure, the largest volumes of global investment are in the Asia-Pacific region, North America, and Europe.Insufficient investment in the accelerated transformation of the world energy market on the basis of sustainable development has been stated in all areas. The targeted efforts of both national governments and the international community are needed to ensure the desired transformation of the global energy market.

Assessment of the potential of polish fly ashes as a source of rare earth elements

Polish energy sector is based on processing of fossil fuels, especially hard coal and lignite. The production of energy from fossil fuels generates large amounts of waste, among which fly ash is distinguished.As the demand for REY increased, alternative sources of these elements began to be desired, including apatite phosphogypsum and ashes from hard coal and lignite combustion.The article presents the results of a comprehensive physicochemical study of 16 Polish fly ashes. The objective was to (i) assess their usefulness as potential alternative sources of rare earth elements and (ii) demonstrate the relationship of rare earth elements with phase and chemical composition, which may be useful in attempts to recover these metals from ashes.The share of REY in the studied Polish fly ashes originating from hard coal combustion is at the level of 300–360 ppm, rarely 500 ppm and, converted to REO oxides, is lower than the value of 1000 ppm considered as the border limit allowing the successful recovery of these metals from low-carbonated coal.Polish fly ashes can be included in the REY prospective raw materials due to the values of the Coutl prospective coefficient, which range from 0.93 to 1.37 (the average Coutl is 1.10), and this coefficient is characterized by low variability (V = 11%).Significant positive and high values of the REY correlation coefficient with the dominant phase components of fly ash (mullite, amorphous enamel) may indicate the desirability of their separation for obtaining these metals, in particular MREY and HREY.Significant positive and high values of the REY correlation coefficient with chemical components such as TiO2, Al2O3, P2O5 and K2O of fly ash may indicate the desirability of grain separation rich in these ingredients to obtain rare earth elements.

Economic Optimization of Resource Use Based on Smart Grid

There are significant changes in society's approaches to the energy policy development in the modern world. It is observable a transition from the old model of the energy sector maintenance, which was dominated by large producers, inefficient networks, fossil fuels, imperfect competition in the markets of natural gas, coal, electricity - to a new model, which creates a more competitive environment and equalizes opportunities for development and the dominance one of the types energy production or sources of fuel supply. The traditional network is based on centralized power plants that supply electricity to consumers through simple one-way transmission and distribution systems. The bulk of the current electricity generation capacity in Ukraine is generated by fossil fuels, which significantly contributes to the increase of the carbon dioxide concentration in the Earth's atmosphere and has a corresponding negative consequences for the climate. At the same time, modern preferences are given to increasing energy efficiency and the use of energy from renewable and alternative sources. Implementation of adaptation and prevention measures for climate change is also one of the priorities of global energy development. The renewable energy promotion is causing new economic and scientific challenges for Ukraine. However, at the same time it opens new perspectives for the search and implementation of innovative developments in the field of extraction, processing of fossil fuels, energy supply and consumption, which leads to create a new energy policy of the state. The article discusses theoretical and methodological approaches that reveal the benefits of Smart Grid using. It is emphasized that ensuring energy security and environmental sustainability of the energy sector should be based on the use of renewable energy sources. The article analyzes the main factors that can affect the development of Smart Grid technology. Also, the article describes the best experience of the EU countries, which are introducing smart energy systems for the economic optimization of renewable energy sources use.

Recent Advances in Heterogeneous Catalyst Design for Biorefining

Biorefineries are a new concept in chemical manufacturing in which naturally occurring, sustainable biomass resources such as forestry and agricultural waste are converted to diverse fuel and chemical product streams, akin to the processing of non-renewable fossil fuels by petrochemical refineries. Biomass derived from waste agricultural and forestry materials or non-food crops offers the most easily implemented and economical solutions for transportation fuels, and the only non-petroleum route to organic molecules for the manufacture of bulk, fine, and speciality chemicals necessary to secure the future needs of society. The successful implementation of biorefineries can address concerns over dwindling oil reserves, carbon dioxide emissions from fossil fuel sources and associated climate change, and will be underpinned by catalytic processes to facilitate the co-production of platform chemicals and biofuels. Catalysis is a central theme in sustainable chemistry, lowering energy and resource requirements while minimising waste production. In contrast to fossil-derived crude oil, which has low oxygen content, the high oxygen and water content of biomass feedstocks presents challenges for their utilisation and requires innovations in catalyst and process design for the selective conversion of these hydrophilic, bulky feedstocks into fuels or high-value chemicals. This article highlights how methods to control porosity, solid acid and base character, and surface hydrophobicity are essential components of a toolkit for the design of heterogeneous catalysts for biomass processing.

Problems of legal regulation of carbon dioxide emissions into the atmosphere

This article is devoted to the problems of legislative regulation of carbon dioxide emissions into the atmosphere. The main sources of carbon dioxide emissions into the atmosphere today are the production, transportation, processing and consumption of fossil fuels (86%), the reduction of tropical forests and other biomass combustion (12%), and other sources. With the advent in the world of the industrial revolution in the mid-nineteenth century, there was a progressive increase in anthropogenic emissions of carbon dioxide in the atmosphere that led to the disruption of the carbon cycle and growth CO2 concentration. Currently, about 57% of the carbon dioxide produced by mankind is removed from the atmosphere by plants and oceans. Carbon dioxide does not belong to toxic gas, however at inhalation of its raised concentrations in air on influence on the air-breathing live organisms carbon dioxide carry to suffocating gases. The concentration of carbon dioxide in the air today is one of the important factors affecting human life and health. Excess of this substance leads to a decrease in productivity, poor health or even death. In addition, carbon dioxide is a greenhouse gas, which is the cause of gradual warming, which is known to have a negative impact on people's lives. Such consequences forced humanity to take measures to reduce the amount of carbon dioxide in the atmosphere and control the volume of carbon dioxide emissions.

Development of a Wireless Surface Acoustic Wave Methane Sensor Using a Metal-Organic Framework As a Sensing Layer for Natural Gas Pipelines

Methane emission from the processing and transportation of fossil fuels can create serious environmental and safety issues as well as a financial burden. The need to monitor the energy infrastructure creates an opportunity for developing low-cost and robust sensors with wireless options. Wireless surface acoustic wave (SAW) devices, which are highly sensitive, cost-efficient, and passive, are a potential candidate for these applications. Nanoporous metal-organic frameworks (MOFs), which can selectively adsorb large amounts of gases in engineered pores at ambient conditions, are potential sensing layers. Here, we present on the development of a wireless and passive SAW sensor using the MOF zeolitic imidazolate framework-8 (ZIF-8) as the sensing layer for methane detection at ambient conditions. The SAW delay lines (nominal operating frequency = 436 MHz) were custom fabricated on Y-Z LiNbO3 piezoelectric substrates and coated with a 500 nm thick ZIF-8 layer using a dip coating method. The devices were excited by 428 MHz RF pulses to test for various concentrations of CO2 and CH4 in N2 background at a constant gas flow rate. Wireless measurements were performed via dipole antennas of nominal resonant frequency 433 MHz. When the sensor was exposed to the gases, surface acoustic wave phase shifted in a negative direction relative to the N2 baseline. This shift was attributed to the decrease in SAW velocity due to the increased mass of the MOF film upon gas adsorption. The CO2 and CH4 sensitivities extracted as the slopes of the respective calibration curves were 1.26 deg/vol-% and 0.03 deg/vol-%, respectively. It is important to note that currently tested minimum concentrations of CO2 and CH4 were 1% and 20%, respectively. Also, the wireless measurements were highly affected by the housing and metal reflectors around it. The demonstration on wireless methane sensing is of great importance for remote monitoring of methane emission sites and transmission pipelines. Our current investigations are focused in advancing the detection limit for leak detection and addressing the electromagnetic interferences in wireless measurement caused by the housing.

Recent Advances in Applications of Acidophilic Fungi to Produce Chemicals.

Processing of fossil fuels is the major environmental issue today. Biomass utilization for the production of chemicals presents an alternative to simple energy generation by burning. Lignocellulosic biomass (cellulose, hemicellulose and lignin) is abundant and has been used for variety of purposes. Among them, lignin polymer having phenyl-propanoid subunits linked together either through C-C bonds or ether linkages can produce chemicals. It can be depolymerized by fungi using their enzyme machinery (laccases and peroxidases). Both acetic acid and formic acid production by certain fungi contribute significantly to lignin depolymerization. Fungal natural organic acids production is thought to have many key roles in nature depending upon the type of fungi producing them. Biological conversion of lignocellulosic biomass is beneficial over physiochemical processes. Laccases, copper containing proteins oxidize a broad spectrum of inorganic as well as organic compounds but most specifically phenolic compounds by radical catalyzed mechanism. Similarly, lignin peroxidases (LiP), heme containing proteins perform a vital part in oxidizing a wide variety of aromatic compounds with H2O2. Lignin depolymerization yields value-added compounds, the important ones are aromatics and phenols as well as certain polymers like polyurethane and carbon fibers. Thus, this review will provide a concept that biological modifications of lignin using acidophilic fungi can generate certain value added and environmentally friendly chemicals.

Thermal dilatation of solid grains: the LBM approach

On the way to present the detailed description of the thermal processing of fossil fuels, one has to face the task of modeling physico-chemical phenomena as complex as thermal dilatation of particles of granular bed in a hot stream of gases. The work presents main assumptions and description of modeling tool for simulate of coal grains thermal dilatations with increasing temperature. For this purpose we use the Lattice Boltzmann method with some schemes needed when the process, of coupled phenomena, in a representative element of granular media is modeled.

Energy–water and GHG nexus: A South African water industry case

Abstract Water and energy are resources that are dependent on each other. Water is needed for the production of energy for fuel extraction, cooling power plants, and processing of fossil fuels. In water cycles, energy is needed for pumping, treatment and distribution of water and wastewater to and from customers. In South Africa (SA), the energy used in the water industry is generated mostly from fossil fuels, which has a significant negative impact on the environment. This research reviews a representative subset of the SA water industry to evaluate energy efficiency and harmful gas emissions optimisation potential. The first component of this study involves a review of the current energy efficiency potential in water distribution systems in SA. On the basis of a literature review, three technologies/practices were identified as being imperative in optimising water utilities in SA. The second part of this study involves the implementation of some performance indicators that illustrate the interdependence of water loss, energy consumption and CO2, NOX and SOX emissions. These indicators are used to compare a few possible mitigation scenarios involving water loss reduction and increasing the system's energy efficiency. The third component of research is developing a novel multi-layered structural water distribution system model by incorporating 29 metrics extracted from the literature reviewed. Analysis of this model is then conducted using a MULTI-MOORA (Multi-Objective Optimization by Ratio Analysis) technique accompanied by a Triangular Fuzzy Number set. The aim of this was to assist water utility managers to identify the most influential performance indicators for attaining the nexus objectives.

Acoustic Sensors Coated with a Metal-Organic Framework for Room Temperature Monitoring of Carbon Dioxide and Methane

Greenhouse gases emissions such as carbon dioxide and methane which are generated from the processing and use of fossil fuels have created serious environmental concerns. The need to monitor the emissions of these gases in mobile and stationary point sources present novel challenges in sensor design. Surface acoustic SAW devices, which offer high sensitivity, low cost, wireless and passive options as well as tunable selectivity when coated with proper sensing materials, can be a potential platform for monitoring these gases. However, many coating materials including metal oxides and polymers are not suitable for developing room temperature gas sensors due to their poor interaction capacity (physisorption or chemisorption) with the gases. Recently, metal-organic frameworks (MOFs) have drawn a considerable attention in sensing applications for their high sorption capacity at ambient condition and functional tenability. Here, we present on the development of surface acoustic wave (SAW) carbon dioxide and methane sensors by applying the zeolitic imidazolate framework-8 (ZIF-8) MOF as the sensing layer. The SAW delay lines with the nominal operating frequency of 436 MHz were custom fabricated on Y-Z LiNbO3 piezoelectric substrates and 9 MHz quartz crystal microbalance (QCM) resonators made of At-cut quartz and gold electrodes were purchased from INFICON. The transducers were coated with 200 nm thick ZIF-8 layer by simple solution-based dip coating method and exposed to various gases at room temperature in a N2 environment. Relative to pure N2, the sensors showed a good response to CO2 and CH4 while remaining neutral to CO and air. The resonance frequency of the QCM sensor decreased by 217 and 9.2 Hz and the phase of the SAW in the delay line changed by 0.72 and 0.04 radian for pure CO2 and CH4, respectively. The responses of the sensors varied linearly with the concentrations of either gas. From a linear fit, the sensitivities of the QCM sensor to CO2 and CH4 were evaluated to be 2.18 Hz/vol-% and 0.1 Hz/vol-%, respectively. Similarly, the SAW sensor showed a sensitivity of 0.39 deg/vol-% to CO2 while its response to various concentrations of CH4 is under study. Since ZIF-8 is a non-conducting material and its stiffness changes negligibly upon gas adsorption for thin film cases, the mass loading effect can be considered the dominant sensing mechanism for both sensors. When the coated films adsorbed the gas molecules, their mass density increased thereby inducing a decrease in acoustic velocity which was recorded in terms of frequency or phase change. Given that the SAW sensors can be operated in wireless and passive mode, the current study is of great importance in developing passive sensors for distant monitoring of greenhouse gases in the environment and at other emission sites.

Heating and cooking in rural Canada: home energy in transition, 1850–1940

ABSTRACTContextualized in very recent histories of energy and in the rich scholarly literature focused on the consumption practices within the home, this article examines the ways that rural Canadians experienced the shift from the organic energy regime (characterized by relatively low energy use and reliance on local rural environments) to the mineral energy regime of fossil fuels and electricity (characterized by high energy use, dense population clusters, and complex networks that distribute energy). Modern grid-supplied energy came very late to rural Canada; the great majority of rural Canadians were still relying on kerosene (paraffin) for lighting and wood for heating and cooking as late as 1941. This article focuses on rural Canadians' long reliance on the wood stove to explore the distinctively slow and late transition that characterized the Canadian transition to the modern energy regime. Although the cast iron wood-burning stove eventually became as emblematic of the ‘backwardness’ of rural life as the coal-oil lamp, the author argues that the wood stove, like the coal oil lamp, was in fact a product of the modern energy regime, and was entangled in networks of extraction, processing, and transportation of fossil fuels along modern coal-and steam networks already transforming rural life.

Designing an optimum carbon capture and transportation network by integrating ethanol distilleries with fossil-fuel processing plants in Brazil

Different long-term mitigation scenarios indicate carbon capture and storage associated with biomass (BECCS) might play a significant role in climate-change mitigation efforts, especially when it comes to long-term temperature stabilization. The ethanol fermentation process is considered as an early opportunity for BECCS deployment due to its low capture costs. Being a major ethanol producer, Brazil stands in a privileged position for the development of this technological option. However, previous scientific studies indicate several challenges for the deployment of a CO2 transportation network in the country, mostly as a result of the associated seasonality of the sugarcane industry and consequent idleness observed in the carbon transportation infrastructure. To address those issues, this study developed and applied a methodology to design an optimum carbon network considering an alternative concept: the incorporation of new CO2 emission sources aiming at guaranteeing adequate operational flows throughout the year, minimizing idleness and reducing transportation costs. Findings indicate that the incorporation of new CO2 emission sources reduces transportation costs. The inclusion of CO2 from both the cogeneration process and fossil sources results in an average levelized cost of transportation of 26 US$/tCO2 (54% lower than transportation costs in the baseline case). However, this reduction in transportation costs does not compensate for the increase in capture costs, resulting in higher levelized abatement costs for the whole system. Indeed, cases including cogeneration have reached a levelized abatement cost of approximately 125 US$/tCO2 (84% higher than in the baseline case). Nevertheless, by reducing transportation costs the strategy adopted in this study could facilitate the development of a carbon transportation network. Additionally, the integration of fossil-derived CO2 has proved beneficial to the system, allowing improvements in flow regularity and reducing idleness problems related to the seasonality of biogenic sources.

Prospects for the deep processing of solid fossil fuels in Belarus

The chemical, thermotechnical, and technological characteristics of the brown coal and bituminous shale of the Republic of Belarus are given, and the areas of their application to power engineering and other branches of national economy are determined. The most promising thermochemical technologies for the processing of the above caustobioliths with the production of fuel and nonfuel materials are analyzed.

Use of biogas from biowaste in a solid oxide fuel cell stack: Application to an off-grid power plant

The development of fuel cells is promising to enable the distributed generation of electricity in the near future. The main candidate fuel for these devices is hydrogen, however, the infrastructure for its production and distribution is currently lacking. In a short to medium term, processing of fossil fuels will play a significant role in hydrogen generation for fuel cells and the use of renewable source – as biogas – is collecting increasing interest at international level. In this work, we consider the use of biogas to feed a solid oxide fuel cell (SOFC) studying separately in details the reforming and the power production. The biogas reforming process was investigated using a thermodynamic and chemical simulation tool. The influence of various operating parameters, such as steam to carbon ratio, carbon deposition and temperature, on the reforming performances was validated, analyzed in-depth and results are presented. Then a model able to provide the polarization curve of the SOFC was implemented and validated. The SOFC model was run using the syngas compositions obtained for three different reforming operating temperatures from 600 to 800 °C. When the temperature increased, the hydrogen molar composition in the syngas increased, whereby the results obtained by the numerical analysis showed an improvement of the SOFC performance as the reforming temperature increased. Afterwards, the reforming/SOFC model was integrated in a hybrid renewable power plant, for an off-grid application. In the proposed case study, a wind turbine and a photovoltaic panel array are used as main energy sources, while the SOFC, together with a battery and a diesel generator, is used as backup system, due to the intrinsic intermittency of main power sources. Three different scenarios, based on different amounts of biogas produced by a biowaste anaerobic digester, have been simulated and analyzed, demonstrating that the power plant is able to achieve 100% renewable operation, provided that the digester produces at least 436 m3/day on average.

Bimetallic Au-Cu Nanocatalysts with Enhanced Electrochemical CO2 Conversion Activity

Converting waste CO2 emissions into value added chemicals and fuels is one approach to mitigating greenhouse gases and reducing the carbon footprint of fossil-fuel processes. The electrochemical CO2 reduction reaction (CO2RR) is a promising carbon mitigation strategy because it can operate at high reaction rates and excellent efficiency at ambient conditions using environmentally friendly aqueous electrolytes. Moreover, the ability to couple carbon-free electricity sources (wind, solar, etc.) enables "carbon neutral" or "carbon negative" technologies that convert CO2into value added products without producing additional emissions. We’ve combined experimental and computational techniques to characterize the catalytic activity of 2-3 nm, bimetallic gold-copper nanoparticles (NPs) for CO2RR. The catalysts showed composition-dependent CO2RR activity that exceeded both the parent gold and copper metals. Interestingly, the bimetallic NPs produced only CO and H2, whereas bulk, polycrystalline copper also produced methane and ethylene. Electrocatalytic activity studies identified 21% Cu NPs as the most active composition with reaction turnover (TOF) frequencies exceeding 60 s-1 and Faradaic Efficiencies approaching 100% FE at -1.0V vs. RHE. The enhanced activity indicates a synergistic effect upon diluting gold atoms in copper. Laboratory and synchrotron-based X-ray spectroscopies were coupled with density functional theory (DFT) to confirm Au-Cu charge transfer within the NPs and identify mixing between near Fermi-level electronic states. We found a strong correlation between the experimentally-determined TOFs and the computationally-predicted binding energy of key reaction products. The superior performance of 21% Cu NPs stemmed from facile desorption of reaction products and extremely weak H binding. This study shows that atomic composition can be used to tune the electronic structure and chemical reactivity of small bimetallic NPs.

Geochemical sources, forms and phases of soil contamination in an industrial city.

This study examines current soil contamination in an Australian industrial city, Newcastle. Public (roadside verges and parks) and private (homes) surface soils (n=170) contained metal(loid)s elevated above their respective Australian Health Investigation Levels (HIL). Lead (Pb), the most common contaminant in the city, exceeds the HIL for residential soils (HIL-A, 300mg/kg) in 88% of private soils (median: 1140mg/kg). In-vitro Pb bio-accessibility analysis of selected soils (n=11) using simulated gastric fluid showed a high affinity for Pb solubilisation (maximum Pb concentration: 5190mg/kg, equating to 45% Pb bio-accessibility). Highly soluble Pb-laden Fe- and Mn-oxides likely contribute to the bio-accessibility of the Pb. Public and private space surface soils contain substantially less radiogenic Pb (range: 208Pb/207Pb: 2.345-2.411, 206Pb/207Pb: 1.068-1.312) than local background soil (208Pb/207Pb: 2.489, 206Pb/207Pb: 1.198), indicating anthropogenic contamination from the less radiogenic Broken Hill type Pb ores (208Pb/207Pb: 2.319, 206Pb/207Pb: 1.044). Source apportionment using Pb isotopic ratio quantification and soil mineralogy indicate the city's historic copper and steel industries contributed the majority of the soil contaminants through atmospheric deposition and use of slag waste as fill material. High-temperature silicates and oxides combined with rounded particles in the soil are characteristic of smelter dust emissions. Additionally, a preliminary investigation of polycyclic aromatic hydrocarbons in soils, sometimes associated with ferrous metal smelting, coal processing or burning of fossil fuels, shows that these too pose a health exposure risk (calculated in comparison to benzo(a)pyrene: n=12, max: 13.5mg/kg, HIL: 3mg/kg).