Hydrocarbon Consumption Research Articles

Bioremediation of oily hypersaline soil and water via potassium and magnesium amendment

Ten hydrocarbonoclastic halobacterial species and 5 haloarchaeal species that had been isolated on a mineral medium with oil as the sole carbon source grew better and consumed more crude oil, as measured by gas-liquid chromatography, in media receiving between 0.50 and 0.75 mol/L KCl and between 1.50 and 2.25 mol/L MgSO₄. Chemical analysis revealed that within a certain limit, the higher the KCl and MgSO₄ concentrations in the medium, the more K⁺ and Mg²⁺, respectively, was accumulated by cells of all the tested halobacteria and haloarchaea. Also, in experiments in which total natural microbial consortia in hypersaline soil and water samples were directly used as inocula, the consumption of hydrocarbons was enhanced in the presence of the above given concentrations of KCl and MgSO₄. It was concluded that amendment with calculated concentrations of K⁺ and Mg²⁺ could be a promising practice for hydrocarbon bioremediation in hypersaline environments.

Compressed Air as a Clean Energy Source for Vehicles

In today’s civilization the excessive use of hydrocarbon fuels in transport sector is causing serious effect on environmental damage to the extent of 77.8% due to its tail pipe emission which mainly releases: carbon dioxide,carbon mono-oxide, nitrous oxide, and other un-burnt gases contributing to green house gases. The excessive consumption of hydrocarbon fuel has also led to the danger of depletion of hydrocarbon fuel and oil wells are likely to be dried around 2047, leaving much disastrous effect like global warming, tsunami, hurricane and health hazards etc.. This paper describes the compressed air as a clean energy source that can be utilized with the help of suitable air driven engine to develop shaft work to run the light transport vehicles along with compressed air storage tank system. A novel rotary air engine has been designed and developed to produce 73-97% of its performance efficiency. Supplementing the hydrocarbon fueled vehicles with the use of compressed air for running vehicles will significantly control the emissions and enhance the energy sustainability.

Effects of soil organic matter and ageing on remediation of diesel-contaminated soil

Bioremediation of diesel-contaminated soil was investigated for the effects of soil organic matter (SOM) and ageing time in two sets of experiments (Batch I and II, respectively). This study examined degradation efficiency in soil artificially contaminated with diesel oil (maximum total petroleum hydrocarbons (TPH) concentration of 9000 mg/kg soil). Batch I data showed that the values of the first-order degradation rate, k, were relatively high in the low-SOM soil batches. The quantity of SOM negatively correlated with the TPH degradation rates and with the total TPH degradation efficiency (%). Introduction of rhamnolipid to the soil proved to be a useful solution to resolve the problem of the residual TPH in the soil with high SOM. In Batch II, the k values decreased with the length of ageing time: 0.0245, 0.0128 and 0.0090 1/d in samples ST0 (freshly contaminated), ST38 (aged for 38 days) and ST101 (aged for 101 days), respectively. The TPH degradation efficiency (%) also decreased along with the ageing time. The research also applied molecular technology to analyse the bacterial community dynamics during the bioremediation course. Multivariate statistics based on terminal-restriction fragment length data indicated: 1) the soils with different SOM resulted in separate bacterial community structures, 2) ageing time created a variety of bacterial communities, 3) the bacterial community dynamics was associated with the hydrocarbon consumption. The SOM content in soils affected the TPH degradation rate and efficiency and the bacterial community structures. Aged soil is more difficult to remediate than freshly contaminated soil, and the resulting bacterial community was less dynamic and showed a lack of succession.

The implications of using hydrocarbon fuels to generate electricity for hydrogen fuel powered automobiles on electrical capital, hydrocarbon consumption, and anthropogenic emissions

This paper considers some of the impacts of adopting hydrogen fuel cell powered electric automobiles in the US. The change will need significant adjustments to the electrical generation industry including additional capital and hydrocarbon fuel consumption as well as impacting anthropogenic greenhouse emissions. Examining the use of three fuels to generate hydrogen fuels, using three production methods, distributed in three geographic scenarios, we determine that while the change reduces anthropogenic greenhouse emissions with minimal additional electrical generation capital expenditures, it accelerates the use of natural gas. Electrolysis provides a sustainable, longer-term solution, but requires more capital investment in electrical generation and yields an increase in anthropogenic greenhouse emissions.

Investigation of the Effects of Biodiesel Feedstock on the Performance and Emissions of a Single-Cylinder Diesel Engine

Biodiesel fuels may serve as a partial solution in the search for sustainable energy sources for the transportation sector. However, increased nitrogen oxide (NOx) emissions are a potentially significant drawback to the use of biodiesel fuels that must be addressed if biodiesel is to gain widespread acceptance. One approach is to identify specific biodiesel fuel properties that minimize NOx formation and use these to produce lower NOx fuel blends. In this work, seven biodiesel fuels were produced from high-erucic rapeseed, olive, palm, coconut, soybean, and fresh and used canola oils, with their chemical composition determined using gas chromatography–mass spectrometry (GC–MS). The fuels were then burned in a single-cylinder direct-injection diesel engine and evaluated for both fuel consumption and exhaust emissions of nitrogen oxides, carbon monoxide (CO), unburned hydrocarbons, and particulate matter. While all biodiesels had higher brake-specific nitric oxide (NO) emissions than ultralow sulfur diesel ...

Establishment of a Database and a Classification of the Defects in the Metal of Pipes According to their Severity

Given the distances between areas of production and consumption of hydrocarbons, transport by pipeline is the most competitive means. These pipelines made of metal pipes can contain several types of defects of different origins. These defects can lead to pipeline failures that may have serious consequences resulting in ecological or financial disasters. The causes of these failures can be of various kinds. To assess the integrity and study the ageing of hydrocarbons transport pipelines is a current problem in the world which must be solved. The degraded state of thousands of kilometers of pipeline in the world requires the elaboration of rehabilitation by repair or replacement programs of sections in poor condition. If on one hand rehabilitation operations do improve the safety of hydrocarbons transport pipelines and prolong their remaining life, they are very expensive on the other. Therefore they must be carried out according to a previously well established plan, which determines the priority given. This priority must be defined by a multi-criteria evaluation, which also includes the criterion of severity of the defects located in the pipes metal according to the result of previous inspections of the pipelines towards the importance and the integrity of each section of the pipe.In this context the elaboration of a database and a classification of the defects in the metal of the hydrocarbons transportation pipes according to their severity are essential in this study.

Performance Analysis of a Dual Fuel Engine Using LPG and Diesel with EGR System

This work is aimed at investigating the performance and emission characteristics of a Dual fuel engine operated with Diesel as primary fuel and ignition source and LPG as secondary fuel with EGR (Exhaust Gas Recirculation) system. In dual fuel operation, much of the energy released comes from the combustion of the gaseous fuel, while only a small amount of diesel fuel provides ignition through timed cylinder injection. The effects of Diesel and LPG substitution ratios, engine speed, and load on the equivalent brake specific fuel consumption and gaseous emissions of hydrocarbons, carbon monoxide and nitrogen oxides are examined for LPG-diesel fuel operation and then compared with the original diesel operation. The concept recirculation of the exhaust gases (EGR), re-burning a part of the exhaust gases is being widely used in many practical situations. The results show that, over a wide range of operating conditions (engine speed, load), the dual fuel engine clearly shows the benefits of reduced NOX emissions. However, under low loads, the results indicate high CO and HC emissions and a higher BSFC when compared to those of the corresponding diesel engine. The LPG addition has been premixed with the engine intake air after the pilot injection of the Diesel in small percentages, in order to improve the engine combustion and to reduce pollutant emissions during the mixing-controlled combustion phase. Experiments show that, using the LPG as an additive fuel, while performing the Diesel fuel main injection keeps the unchanged engine efficiency with respect to the traditional Diesel fuel operation mode.

Mathematical modeling of marine environment pollution processes by petroleum hydrocarbons and their degradation in Caspian Sea ecosystem

The available observational data on the pollution of tributaries and areas of the Caspian Sea by petroleum hydrocarbons and products are examined. The possible petroleum input from sources in the sea is assessed using up-to-date data of satellite observations of sea surface pollution by oil films. The hydroecological CNPSi-model is applied to studying water pollution processes by petroleum hydrocarbons in ten areas chosen in the Caspian Sea and the subsequent biodegradation of those pollutants. The model calculations of the within-year dynamics of petroleum hydrocarbon concentrations use mean annual observational data on within-year variations in water mediium characteristics (water temperature, light intensity, and transparency), as well as the morphometric parameters of sea areas (the area, mean depth, and water volumes). The characteristics of water exchange between the areas were evaluated using a hydrodynamic model. The model calculations were used to characterize the within-year variations in petroleum hydrocarbon concentrations, the biomasses of petroleum-oxidizing bacteria, the characteristics of their oxidation activity and bioproduction, and the internal fluxes of petroleum hydrocarbons (their input from various sources, horizontal and vertical transport, and biotransformation) in different sea areas. Calculation results were used to compile annual balances for the processes of input and consumption of petroleum hydrocarbons in the chosen and aggregated sea areas.

Effect of EGR on the Exhaust Gas Temperature and Exhaust Opacity in Compression Ignition Engines Using Jatropha Oil as Fuel

Diesel engines are widely used as power sources for medium and heavy-duty applications because of their lower fuel consumption and lower emissions of carbon monoxide (CO) and unburned hydrocarbons (HC) compared with gasoline engines. Efficient use of natural resources is one of the fundamental requirements for any country to become self-sustainable. Both in organized and unorganized sectors internal combustion engine has become an indispensable prime mover. With the increasing demand on the use of fossil fuels, a stronger threat to clean environment is being posed as the burning of fossil fuels is associated with emissions like CO2, CO, SOx, NOx and particulate matter, which are currently the dominant global source of emissions. In diesel engines, NOx formation is a highly temperature-dependent phenomenon. Therefore, in order to reduce NOx emissions in the exhaust, it is necessary to keep peak combustion temperatures under control. Exhaust gas recirculation is the most important technique for reducing NOx emissions. Re-circulating part of the exhaust gas helps in reducing NOx, but appreciable particulate emissions are observed at high loads, hence there is a trade-off between NOx and smoke emission. To get maximum benefit from this trade-off, a particulate trap may be used to reduce the amount of unburnt particulates in EGR, which in turn reduce the particulate emission also. An experimental investigation was conducted to observe the effect of exhaust gas re-circulation on the exhaust gas temperatures and exhaust opacity. The experimental setup for the proposed experiments was developed on a single-cylinder, direct injection, air-cooled, compression ignition engine. A matrix of experiments was conducted for observing the effect of different quantities of EGR on exhaust gas temperatures and opacity.

Indigenous soil bacteria with the combined potential for hydrocarbon consumption and heavy metal resistance

Transconjugant bacteria with combined potential for hydrocarbon utilization and heavy metal resistance were suggested by earlier investigators for bioremediation of soils co-contaminated with hydrocarbons and heavy metals. The purpose of this study was to offer evidence that such microorganisms are already part of the indigenous soil microflora. Microorganisms in pristine and oily soils were counted on nutrient agar and a mineral medium with oil as a sole carbon source, in the absence and presence of either sodium arsenate (As V), sodium arsenite (As III) or cadmium sulfate, and characterized via 16S rRNA gene sequencing. The hydrocarbon-consumption potential of individual strains in the presence and absence of heavy metal salts was measured. Pristine and oil-contaminated soil samples harbored indigenous bacteria with the combined potential for hydrocarbon utilization and As and Cd resistance in numbers up to 4 × 10⁵ CFU g⁻¹. Unicellular bacteria were affiliated to the following species arranged in decreasing order of predominance: Bacillus subtilis, Corynebacterium pseudotuberculosis, Brevibacterium linens, Alcaligenes faecalis, Enterobacter aerogenes, and Chromobacterium orangum. Filamentous forms were affiliated to Nocardia corallina, Streptomyces flavovirens, Micromonospora chalcea, and Nocardia paraffinea. All these isolates could grow on a wide range of pure aliphatic and aromatic hydrocarbons, as sole sources of carbon and energy, and could consume oil and pure hydrocarbons in batch cultures. Low As concentrations, and to a lesser extent Cd concentrations, enhanced the hydrocarbon-consumption potential by the individual isolates. There is no need for molecularly designing microorganisms with the combined potential for hydrocarbon utilization and heavy metal resistance, because they are already a part of the indigenous soil microflora.

Effect of surfactant and oil additions in the biodegradation of hexane and toluene vapours in batch tests

The biological treatment of gaseous emissions of hydrophobic volatile organic compounds (VOCs) results in low rates of elimination partially because of the low solubility of VOCs in water. Recently, the use of two‐phase partition bioreactors (TPPBs) was proposed to increase the bioavailability and consequently the elimination capacities of this kind of VOC. In the present study, TPPBs operating in a batch feed mode were tested for biodegradation of hexane and toluene vapours with a microbial consortium. The results obtained were compared with single‐phase systems (control experiments). The liquid phase used was silicone oil (organic phase) with the surfactant Pluronic F‐68. Experiments were named F1 and F2 for one and two phases, respectively, and F1S and F2S when the surfactant was included. The maximum specific rates (Srates) of hydrocarbon consumption for hexane and toluene were 539 and 773 mghydrocarbon/(gprotein·h), respectively. For both substrates, the systems that showed the highest Srates of hydrocarbon consumption were F2 and F2S. In experiment F1S the surfactant Pluronic F‐68 increased the solubility of hydrocarbons in the liquid phase, but did not increase the Srates. The maximum percentages of mineralization were 51% and 72% for hexane and toluene, respectively. The results showed that simultaneous addition of silicone oil and surfactant favours the mineralization, but not the rate of biodegradation, of toluene and hexane vapours.

Developing a High-Resolution Vehicular Emission Inventory by Integrating an Emission Model and a Traffic Model: Part 2—A Case Study in Beijing

A grid-based, bottom-up method has been proposed by combining a vehicle emission model and a travel demand model to develop a high-resolution vehicular emission inventory for Chinese cities. Beijing is used as a case study in which the focus is on fuel consumption and emissions from hot-stabilized activities of light-duty gasoline vehicles (LGVs) in 2005. The total quantity of emissions, emission intensity, and spatial distribution of emissions at 1- by 1-km resolution are presented and compared with results from other inventory methods commonly used in China. The results show that the total daily fuel consumption and vehicular emissions of carbon dioxide, carbon monoxide, hydrocarbons, and oxides of nitrogen from LGVs in the Beijing urban area in 2005 were 1.95 × 107 L, 4.28 × 104 t, 1.97 × 103 t, 0.28 × 103 t, and 0.14 × 103 t, respectively. Vehicular fuel consumption and emissions show spatial variations that are consistent with the traffic characteristics. The grid-based inventory developed in this study reflects the influence of traffic conditions on vehicle emissions at the microscale and may be applied to evaluate the effectiveness of traffic-related measures on emission control in China.

THE EFFECT OF BIODIESEL FUEL FROM RUBBER (HEVEA BRASILIENSIS) SEED OIL ON A DIRECT INJECTION (DI) DIESEL ENGINE

The extensive biodiversity of ASEAN countries includes many plants producing fatty-oils with yield potentials sufficient for biodiesel production. Seed of the rubber tree (Hevea brasiliensis) is perhaps one with significant potential because of the extensive areas of rubber plantations within ASEAN. Rubber seed oil is virtually unexploited commercially, probably because it is non-edible. Consequently, it has the potential to replace/substitute for edible oils such as palm oil, coconut oil, etc. as a raw material for biodiesel during periods of high food sector demand. Currently, the main product of the rubber tree is rubber milk, the raw material for latex and rubber industries. Rubber seed is a byproduct. The kernels constitute 50 to 60% of the seed and contain 40 to 50% brown oil. In this study, the engine test bed procedure for testing coking of DI diesel engine injector nozzles was utilized to examine the effect of using neat Rubber seed oil biodiesel (RSB), and blends with diesel oil as fuel. The effect of the fuels on engine components and exhaust gas emissions such as Hydrocarbon (HC), Carbon Monoxide (CO), Smoke and Brake Specific Fuel Consumption (BSFC) was investigated. The performance and emissions of B5 fuel was comparable with diesel fuel; the use of B100 resulted in significantly higher BSFC (23%); higher emissions (20.83% CO, 27.78% THC, 20.80% opacity before commencement of the endurance test, 13.73% CO, 5.79% THC, 33.33% opacity after endurance test). Pure RSB and B5 reduced deposits on the cylinder head (38.74% and 35.82% respectively) but RSB increased deposits on the piston (37.42%).

Mercury resistance and volatilization by oil utilizing haloarchaea under hypersaline conditions

The hydrocarbon utilizing haloarchaea, Haloferax (two strains), Halobacterium and Halococcus from a hypersaline coastal area of the Arabian Gulf, had the potential for resistance and volatilization of Hg(2+). Individual haloarchaea resisted up to between 100 and 200 ppm HgCl₂ in hydrocarbon free media with salinities between 1 and 4 M NaCl, but only up to between 20 and 30 ppm in a mineral medium containing 3 M NaCl, with 0.5% (w/v) crude oil, as a sole source of carbon and energy. Halococcus and Halobacterium volatilized more mercury than Haloferax. The individual haloarchaea consumed more crude oil in the presence of 3 M NaCl than in the presence of 2 M NaCl. At both salinities, increasing the HgCl₂ concentration in the medium from 0 to 20 ppm resulted in decreasing the oil consumption values by the individual haloarchaea. However, satisfactory oil consumption still occurred in the presence of 10 ppm HgCl₂. It was concluded that haloarchaea with the combined potential for mercury resistance and volatilization and hydrocarbon consumption could be useful in removing toxic mercury forms effectively from oil free, mercury contaminated, hypersaline environments, and mercury and oil, albeit less effectively, from oily hypersaline environments.

Enrichment of rhizospheres of crop plants raised in oily sand with hydrocarbon-utilizing bacteria capable of hydrocarbon consumption in nitrogen free media

The rhizospheres of the three legume crops, peas, beans and peanuts and the three nonlegume crops, sunflower, tomato and mallow raised in pristine sand were associated with between 1 and 1.4 × 10 6 hydrocarbon-utilizing bacteria per gram root. These values were much higher when the plants were raised in oily sand. Thus, numbers of the hydrocarbon-utilizing rhizobacteria of the legume crops ranged between 21.2 and 50.1 × 10 6 cells g −1 roots and of the nonlegumes sunflower and tomato only between 6.5 and 8.7 × 10 6 cells g −1 roots. According to their 16S rRNA gene sequences, the predominant oil-utilizing bacteria in rhizospheres of the legumes pea and beans, were affiliated with Microbacterium oxydans, Pseudomonas plecoglossicida and Acidovorax delafieldii. Other minor oil-utilizing bacteria were also identified and recorded. Pure cultures of all these bacteria could consume crude oil, n-octadecane (an aliphatic hydrocarbon) and phenanthrene (an aromatic hydrocarbon) in nitrogen containing, but also in nitrogen free media. The latter finding suggests that these organisms may be self sufficient regarding their nitrogen nutrition. It was therefore concluded that the use of legume crops for phytoremediation of oily desert soils through rhizosphere technology, saves the use of nitrogen fertilizers, making the phytoremediation process more economical and environmentally friendly.

Agarolytic bacteria with hydrocarbon-utilization potential in fouling material from the Arabian Gulf coast

Fouling material adhering to a neglected navigation vehicle half-sinking in the coastal water of the Arabian Gulf harbored two agarolytic bacterial species, Halomonas aquamarina and Alteromonas macleodii with hydrocarbon-utilization potential. Both species were halophilic (optimum 2–5% NaCl, w/v), slightly alkaliphilic (optimum pH 8) and grew best at 25 °C. The oil and hydrocarbon consumption potential of both species was dramatically enhanced (2 fold or more) by the addition of agar powder to the liquid medium. Both organisms were able to grow on a nitrogen free medium. These results imply that such agarolytic bacteria could potentially be suitable biological systems for self-cleaning and bioremediation of oily marine ecosystems.

Study of the influence of vane angle on shaft output of a multivane air turbine

Faster consumption of hydrocarbon fuel in the transport sector is posing global threat of depletion of fossil fuel reserves. Studies are being extensively done to search for an alternative energy source and/or to find out appropriate energy conversion system. Among various alternatives, the use of compressed atmospheric air in air turbine is an attractive option provided the atmospheric air is compressed by natural sources such as sun energy, wind energy, etc. It has the capability to produce shaft work with almost zero pollution in the environment. This paper details the mathematical modeling of a small capacity compressed air driven multivane air turbine. The effect of having different vane angles and inlet pressure on shaft work output has been studied and analyzed here. The study shows that the flow work has significant contribution in total work output and varies from 1.5% to 16.3% at different pressures, 2–6 bars, and injection angles, 30°–60°. The total shaft work is found to be maximum at vane angle θ=36° (ten vanes) when injection angle is kept at 60°, and it reduces at vane angle θ=45° (eight vanes) when injection angle is kept at 45° and further goes down at vane angle θ=60° (six vanes) when injection angle is 30°, if injection pressure is maintained at 6 bars and speed of rotation at 2500 rpm.

Exhaustive catalytic hydrodechlorination

To develop technology for the utilization of waste from vinyl chloride production by the method of catalytic hydrodechlorination, the main aspects of kinetics are studied, which makes it possible to describe the process of exhaustive catalytic hydrodechlorination on a Pd/γ-Al2O3 catalyst. Conditions are determined that provide stable work of the catalyst and the complete extraction of chlorine from waste: excess hydrogen of ∼270°C and a contact time of 10–15 s. The process does not require high pressure. The rate of chlorinated hydrocarbon consumption in the process of hydrodechlorination of the main components of waste (1,2-dichloroethane, 1,1,2-trichloroethane, and tetrachloroethylene) is measured at 200–270°C. Mathematical equations for simulations of the hydrodechlorination reactor unit are obtained. The results can be used to develop an experimental pilot plant.

Performance and gaseous emissions characteristics of a natural gas/diesel dual fuel turbocharged and aftercooled engine

The aim of this paper is to investigate the performance and emissions characteristics of a turbocharged and aftercooled diesel engine operated with natural gas as primary fuel, and diesel fuel as ignition source. In such dual fuel operation, much of the energy released comes from the combustion of the gaseous fuel, while only a small amount of diesel fuel provides ignition through timed cylinder injection. The effects of diesel-natural gas substitution ratios, engine speed, and load on the equivalent brake specific fuel consumption and gaseous emissions of hydrocarbons, carbon monoxide and nitrogen oxides are examined for natural gas-diesel fuel operation and, afterward, compared with the original diesel operation. The results show that, over a wide range of operating conditions (engine speed, load), the dual fuel engine clearly shows the benefits of reduced NOX emissions. However, under low loads, the results indicate high CO and HC emissions and a higher BSFC when compared to those of the corresponding diesel engine.

Biodegradability of commercial and weathered diesel oils

This work aimed to evaluate the capability of different microorganisms to degrade commercial diesel oil in comparison to a weathered diesel oil collected from the groundwater at a petrol station. Two microbiological methods were used for the biodegradability assessment: the technique based on the redox indicator 2,6 -dichlorophenol indophenol (DCPIP) and soil respirometric experiments using biometer flasks. In the former we tested the bacterial cultures Staphylococcus hominis, Kocuria palustris, Pseudomonas aeruginosa LBI, Ochrobactrum anthropi and Bacillus cereus, a commercial inoculum, consortia obtained from soil and groundwater contaminated with hydrocarbons and a consortium from an uncontaminated area. In the respirometric experiments it was evaluated the capability of the native microorganisms present in the soil from a petrol station to biodegrade the diesel oils. The redox indicator experiments showed that only the consortia, even that from an uncontaminated area, were able to biodegrade the weathered diesel. In 48 days, the removal of the total petroleum hydrocarbons (TPH) in the respirometric experiments was approximately 2.5 times greater when the commercial diesel oil was used. This difference was caused by the consumption of labile hydrocarbons, present in greater quantities in the commercial diesel oil, as demonstrated by gas chromatographic analyses. Thus, results indicate that biodegradability studies that do not consider the weathering effect of the pollutants may over estimate biodegradation rates and when the bioaugmentation is necessary, the best strategy would be that one based on injection of consortia, because even cultures with recognised capability of biodegrading hydrocarbons may fail when applied isolated.