Refinery Complex Research Articles

DETERMINATION OF HEAVY METALS AND TOTAL PETROLEUM HYDROCARBONS IN SOIL SAMPLES AND PLANT LEAVES AROUND OIL REFINERIES LOCATED ON ERBIL-GWER ROAD

Several refinery complexes exist in the Kurdistan Region of Iraq that produce various kinds of petroleum products. During the refining process, different types of gases, metals, hydrocarbons, and liquids are discharged into the environment. This study aimed to determine the concentration of eight heavy metals in soil and plant leaves collected around the refineries along Erbil-Gwer Road on two occasions throughout the study period. Additionally, we aimed to evaluate the levels of Total Petroleum Hydrocarbons (TPH) in the soil samples from the area. The results of the analysis revealed significant differences (P<0.05) in the concentrations of Pb, Ni, Cd, Cr, As, and Mn between the dry and wet seasons in the soil samples. However, no significant differences were observed for Cu and Zn between the two seasons. The levels of metals for both periods were as follows: Mn> Cr> Zn> Ni> Cu> Pb> As> Cd in successive forms. Regarding the plant leaves, significant differences (P<0.05) were found between the study periods for Pb, Cu, Zn, and Cd, whereas no significant differences were observed for the other metals. Furthermore, the concentration of TPH in the soil samples located alongside the refinery effluent stream was higher compared to the other areas.

Summer and winter variations of BTEX concentrations in an oil refinery complex and health risk assessment based on Monte-Carlo simulations

The summer and winter concentrations of BTEX pollutants were investigated in various workplaces of an oil Refinery, Iran. In total 252 air samples from the breathing zones of the following employees were collected: supervisors, safetymen, repairmen, site men, and all workers. Carcinogenic and non-carcinogenic risk values were calculated based on the USEPA methodology using Monte Carlo simulations. BTEX concentrations were higher in the summer than in the winter season for all workstations, especially for toluene and ethylbenzene. The mean values of exposure to benzene for repairmen and site men were higher than threshold limit value of 1.60 mg/m3 for both seasons. Non-carcinogenic risk (HQ) values calculated for summer season for benzene, ethylbenzene, and xylene in all workstations, as well as for toluene for repairmen and site men exceeded acceptable level of 1. In winter season the mean HQ values for benzene and xylene in all workstations, for toluene for repairmen and site men, and for ethylbenzene for supervisors, repairmen, and site men were also > 1. For all workstations definite carcinogenic risk was indicated as calculated LCR values for benzene and ethylbenzene exposure were higher than 1 × 10–4 in both summer and winter seasons.

A framework for salvaging megaprojects in Africa based on a case study of a refinery and petrochemical complex project

Navigating megaprojects to successful completion in low- and middle-income countries is fraught with challenges, often leading to numerous abandoned or underutilised projects. This study bridges a research gap by proposing a framework for salvaging distressed megaprojects using Integrated Project Delivery (IPD), derived from literature review, critical reflection, and expert consultation. The IPD framework offers strategies for immediate and sustained recovery of troubled megaprojects, including refining procurement strategies, restructuring organisational architecture, and leveraging IPD best practices. This research aids key decision-makers in understanding failure causes and equips them with strategies to salvage failing projects. It contributes to the global discourse on sustainable project management, aligning with UN's SDGs, specifically SDG 9, 8 and 17. The framework can also contribute to Africa Union's Agenda 2063, fostering infrastructure and economic development. This study provides an innovative solution to enhance the success rates of ongoing megaprojects, aligning with broader sustainable development objectives.

Development and validation of a task load index for process control room operators (PCRO-TLX)

Process control room operators (PCRO) perform a range of complex cognitive safety-critical tasks. The aim of this exploratory sequential mixed methods study was to develop an occupation specific tool to measure the task load of PCRO using NASA Task Load Index (TLX) methodology. Participants were 30 human factors experts and 146 PCRO at two refinery complexes in Iran. Dimensions were developed via a cognitive task analysis, a research review, and three expert panels. Six dimensions were identified: perceptual demand, performance, mental demand, time pressure, effort, and stress. Data from 120 PCRO confirmed that the developed PCRO-TLX has acceptable psychometric properties, and a comparison with the NASA-TLX confirmed that perceptual, not physical, demand was relevant for measuring workload in PCRO. There was a positive convergence of scores of the Subjective Workload Assessment Technique and the PCRO-TLX. This reliable tool (α = 0.83) is recommended for risk assessing the task load of PCRO. Practitioner summary: There are benefits of having a specific tool to measure task load in safety critical roles. Thus, we developed and validated an easy-to-use targeted tool, the PCRO-TLX, for process control room operatives. Timely use and response will assure optimal production alongside health and safety in an organisation. Abbreviations: PCRO: process control room operator; TLX: task load index; PCRO-TLX: process control room operator task load index; NASA-TLX: National Aeronautics and Space Administration task load index; SWAT: subjective workload assessment technique; DALI: driving activity load index; SURG-TLX: surgery task load index; SIM-TLX: virtual reality simulation task load index; VACP: visual, auditory, cognitive and psychomotor; CVI: content validity index; CVR: content validity ratio; RMSEA: root mean square of error approximation; GFI: goodness of fit index; AGFI: adjusted goodness of fit index; CFI: comparative fit index; ANOVA: analysis of variance; CI: confidence interval

Refinery town in the petrostate: organized labour confronts the oil patch in Western Canada

In 2019, Regina’s Co-operative Refinery Complex locked out the 730 members of Unifor Local 594 amid record profits in an aggressive drive for significant pension concessions. Marred by sweeping antipicketing injunctions, an enormous scab operation, police repression, and general public enmity, the lockout suggests two overlapping trends. First, the union’s adherence to co-operative and conciliatory bargaining had left it ill equipped to confront—either in the workplace or the public sphere—management’s costcutting agenda in the centre of Saskatchewan’s now hegemonic petrostate. Second, a marked tension developed between community outreach efforts and the circumstances in which legal industrial action was ineffective and civil disobedience emerged.

Monitoring TPH biodegradation in soil around Ray oil refinery by natural attenuation, biostimulation and bioaugmentation treatments

In this study, total petroleum hydrocarbons (TPHs) decontaminating mechanisms for soils around the Rey refinery complex (South of Tehran, Iran) was investigated. Natural attenuation, biostimulation and bioaugmentation (separately and in combination) methods were evaluated TPHs and soil microbial respiration in 210 days, using laboratory treatments The modified methods were applied through 13 different treatments, including improving the environmental conditions for native bacteria (natural attenuation for treatments 1-8), adding non-native bacterial complex (bioaugmentation for treatment 9) and intensifying and stimulating growth while adding non-native bacterial complex (biostimulation-bioaugmentation for treatments 10-13). Although, overall of the treatments, a significant decreasing TPHs concentration were observed over the time, biostimulation-bioaugmentation treatments had the highest amount of TPHs decomposition, the highest rate of bio-respiration, the lowest half-life times (t1/2), and the highest remediation efficiency and biodegradation constants rate. Among natural attenuation treatments, modifiers with manure and sawdust had the greatest effect on reducing the TPHs concentration and the highest rate of bio-respiration. The first-order kinetic model was fitted to the data related to biodegradation in a satisfactory manner. The results showed that there was a strong and positive linear correlation between decreasing TPHs concentration and microbial respiration in all modifiers. Although for the bacterial treatments and at the early stages of inoculation, the rate of total respiration was low, but as the time passed and with adaptation of the effective inoculated bacteria to contaminated soil, the respiration rate gradually was increased. Due to its low cost and low environmental risk, the proposed bioremediation technique for oil contaminated soil can be recommended to the region.

Development of inferential sensor and real-time optimizer for a vacuum distillation unit by recurrent neural network modeling of time series data

In lube base oil production, a vacuum distillation unit (VDU) is a crucial unit operation which must be controlled tightly to meet final product specifications. To address this requirement, model-based optimal control can be employed, which requires an accurate model relating to the operation and quality variables involved. However, the mathematical modeling of VDU is hampered by the lack of process knowledge and the limited online data acquisition capability for key quality variables. As a recourse, data-based modeling can be attempted to develop inferential sensors and controllers but one is faced with the problem of temporal credit assignment due to the complex characteristics of the VDU process dynamics, e.g., varying time-lags among the variables. To overcome this difficulty, the use of a stacked RNN structure with sequence length is proposed for the prediction of kinematic viscosity. In addition, regression models for the product's distillation temperatures are constructed by testing a large number of regression model structures. Then, these quality predictors are applied in developing a real-time optimizer which adjusts key operating variables in order to satisfy the product specifications despite various disturbances. Accuracies of the soft sensor and the optimization model are evaluated, first offline and then, online through a commercial plant test performed at SK Ulsan Refinery Complex in Korea. The overall approach and framework are general and can be used for the development of inferential sensors and controllers in other similar situations.

Studying a Multi-Stage Flash Brine Recirculation (MSF-BR) System Based on Energy, Exergy and Exergoeconomic Analysis

Due to the lack of natural water resources and high consumption of water in industries, desalination systems are good options to supply water demands, especially in regions with a water crisis. If these wastes are used in thermal desalination cycles, in addition to improving efficiency and reducing energy consumption, the production of environmental pollutants can also be reduced. In this paper, the multi-stage flash brine recirculation (MSF-BR) system of the Abadan refinery is investigated from energy-exergy-exergoeconomic viewpoints. In addition, the effects of top brine temperature (TBT), number of stages and ambient temperature on the performance of the system are evaluated. The results at maximum brine temperature show that with increasing the TBT, the exergy efficiency, gained output ratio (GOR) and distillate water production increase by 34%, 47% and 47%, respectively. It is also found that if the number of stages in the heat rejection section increases to more than six stages, GOR will decrease. The exergoeconomic analysis results reveal that the relative cost difference increases by 94% with an increase in the number of stages. Finally, it is concluded that by using the waste heat of a refinery complex for heating steam to run the desalination system, there is a 9103 $/year cost savings due to energy consumption reduction and 193 × 104 $/year cost savings due to CO2 emission reduction.

Analysing the spatial distribution of land surface temperature at Nghi Son Refinery and Petrochemical Complex using Landsat and Sentinel 2 satellite image data

The Landsat 5, Landsat 8 and Sentinel 2A satellite image data are used for extracting land surface temperature, thereby mapping the spatial distribution of land surface temperature at Nghi Son Refinery and Petrochemical Complex. The obtained results then can be used in monitoring land surface temperature changes, for land use planning as well as in minimising the impact of production processes to the environment.

Determiners of Refinery Complexity: An Overview

Determiners of Refinery Complexity: An Overview

Pyro-gas analysis of fixed bed reactor end of life tyres (ELTs) pyrolysis: A comparative study

Pyrolysis of end of life tyres (ELTs) present a promising alternative to their incineration or classical product recovery using mechanical means. It can produce light hydrocarbons (HCs) and other valuable chemicals as part of the pyro-gas stream it generates. In this work, two grades of tyres namely a fresh (virgin) one and a waste disposed ELTs, were used as a feedstock to analyse their pyro-gas constituents. There wasn't much difference in the maximum conversion rate between both tyre grades where the fresh tyres had an estimated 15.17% conversion and the ELTs was 13.45% conversion (both at 800 °C). The difference herein was attributed to release of free radicals prior to subjecting the samples to pyrolysis due to their history. The analysis of the pyro-gas samples showed a large make of light hydrocarbon (HC) products, namely methane (CH4/C1), ethane (C2H6/C2), ethylene (C2H4), propane (C3H8/C3), propylene (C3H6), n-butane (C4H10), butadiene compounds, carbon mono and dioxide (CO,CO2). Light HCs mimciking natural gas were more abundant in the case of ELTs were C1 was estimated as 14.53% at 500 °C and 16.73% at 800 °C. C2 was also estimated higher than the fresh tyres where a 11.78% at 500 °C was noted and 7.67% at 800 °C. It can be recommended that future integration plans in oil and gas ventures, namely refinery and petrochemical complexes, are to start taking responsible measures towards the environment by substituting part of their operations with sustainable feedstock such as ELTs.

The mediator role of safety motivation and knowledge between safety culture and safety performance: The results of a sociotechnical and macroergonomics approach.

Nowadays, although the effect of positive safety culture on improving safety performance has been confirmed, the mechanisms of this effect are somewhat ambiguous. This study aimed to investigate the direct and indirect effects of safety culture on safety performance based on a sociotechnical and macroergonomics approach. The participants consisted of 276 workers, supervisors, and managers in an oil and gas refinery complex. The data collection conducted using questionnaires including safety culture in accordance with the organization's sociotechnical characteristics with 12 dimensions (effectiveness of safety management, management's attitude towards safety, training, awareness and safety policy, peer support, work schedule, job demands, confrontation of tasks and safety, behavioural features and commitment to safety, work equipment and tools, personal protective equipment, workplace hazards, and external environmental factors), safety motivation and safety knowledge as mediators between safety culture and safety performance, and safety compliance and safety participation as the components of safety performance. The examination of paths in three structural models indicated that in the presence of the direct effect, the indirect paths were not approved due to the lack of confirmation of safety motivation ⟶ safety performance and safety knowledge ⟶ safety performance. In the model without the direct effect, indirect paths were confirmed; however, a low amount of safety performance variance was explained by safety culture. The safety culture tool explained the highest value of variance for the direct path due to the use of industry-related factors.

Characteristics and Impact of VOCs on Ozone Formation Potential in a Petrochemical Industrial Area, Thailand

In this study, the ambient concentrations of volatile organic compounds (VOCs) were intensively measured from January 2012 to December 2016 using an evacuated canister and were analyzed using a gas chromatography/mass spectrophotometer (GC/MS) based on the US EPA TO-15 in the community and industrial areas of the largest petroleum refinery and petrochemical industrial complex in Map Ta Phut Thailand. The ternary diagram was used to identify the source of VOCs. Reactivity of VOCs on their ozone formation potential (OFP) were quantified by the maximum incremental reactivity coefficient method (MIR) and propylene-equivalent concentration methods. Results from the study revealed that aromatic hydrocarbon was the dominant group of VOCs greatly contributing to the total concentration of measured VOCs. Among the measured VOCs species, toluene had the highest concentration and contributed as the major precursor to ozone formation. The ternary analysis of benzene:toluene:ethybenzene ratios indicated that VOCs mainly originated from mobile sources and industrial processes. Within the industrial area, measured VOC concentration was dominated by halogenated hydrocarbons, and alkene was the highest contributor to ozone formation. The propylene-equivalent concentration method was also used to evaluate the reactivity of VOCs and their role in ozone formation, and secondly to support findings from the MIR method.

Fully integrated CO2 mitigation strategy for an existing refinery: A case study in Colombia

The oil and gas industry is responsible for 6% of total global CO2 emissions, from exploration to downstream petrochemical production and account for another 50% when including the use of its products. Thus, this industry has a significant role in realising the target of net “zero” CO2 emissions by 2070, essential to limit global warming to 1.8 °C [2], as introduced under the Paris agreement. Currently, the interactions of an extensive set of individual and combined CO2 mitigation measures along the value chain and over time are poorly assessed. This paper aims to assess a bottom-up CO2 mitigation potential for a complex refinery, including portfolios of combined mitigation options, considering synergies, overlap, and interactions over time for more realistic insight into the costs and constraints of the mitigation portfolio. A total of 40 measures were identified, covering a wide range of technologies such as energy efficiency measures (EEM), carbon capture and storage (CCS), bio-oil co-processing, blue and green hydrogen (BH2, GH2), green electricity import, and electrification of refining processes linked to the transition of the Colombian energy systems. Five deployment pathways were assessed to achieve different specific targets: 1-base case scenario, 2-less effort, 3-maximum CO2 avoidance, 4-INDC, and 5-measures below 200 €/t CO2. Two scenarios (3 and 5) gave the highest GHG emission reduction potentials of 106% and 98% of refining process emissions, respectively. Although significant, it represent only around 13% of the life-cycle emissions when including upstream and final-use emissions of the produced fuels. Bio-oil co-processing options account for around 60% of the mitigation options portfolio, followed by CCS (23%), green electricity (7%) and green H2 (6%). The devised methodological approach in this study can also be applied to assess other energy-intensive industrial complexes and shed light on the bias for estimating CO2 mitigation potentials, especially when combining different mitigation options. This is turn is vital to define optimal transition pathways of industrial complexes.

Energy and Environmental Assessment of Steam Management Optimization in an Ethylene Plant.

Steam crackers (ethylene plants) belong to the most complex industrial plants and offer significant potential for energy-saving translated into the reduction of greenhouse gas emissions. Steam export to or import from adjacent units or complexes can boost the associated financial benefit, but its energy and environmental impact are questionable. A study was carried out on a medium-capacity ethylene plant using field data to: 1. Estimate the energy savings potential achievable by optimizing internal steam management and optimizing steam export/import; 2. Quantify the associated change in air pollutant emissions; 3. Analyze the impact of the increasing carbon price on the measures adopted. Internal steam management optimization yielded steam let-down rate minimization and resulted in a 5% (87 TJ/year) reduction in steam cracker’s steam boiler fuel consumption and the associated cut of CO2 emissions by almost 4900 t/year and that of NOx emissions by more than 5 t/year. Steam import to the ethylene plant from the refinery proved to be purely economic-driven, as it increased the net fuel consumption of the ethylene plant and the refinery complex by 12 TJ/year and resulted in an increase of net emissions of nearly all considered air pollutants (more than 7000 t/year of CO2, over 15 t/year of NOx, over 18 t/year of SOx) except for CO, where the net change was almost zero. The effect of external emissions change due to the associated backpressure electricity production surplus (over 11 GWh/year) was too low to compensate for this increase unless fossil fuel-based electricity production was considered. The increase of carbon price impact on the internal steam management optimization economics was favorable, while a switch to steam export from the ethylene plant, instead of steam import, might be feasible if the carbon price increased to over 100 €/tCO2.

The tenacity of trust in petrochemical communities: Reckoning with risk on the Fawley Waterside (1997–2019)

Around the world, people living close to polluting industries have different perceptions of the risks of toxic exposure, ranging from anger to acceptance to denial. We draw attention to a case with relatively high levels of social trust, but also relatively high levels of risk perception: the communities living adjacent to the Fawley (UK) oil refinery and petrochemical complex, a site that has been operated by Esso since the early 1950s.Our findings are based on a novel comparative analysis of two qualitative studies of local risk perceptions in Fawley conducted more than two decades apart in 1997 and 2019, incorporating focus group and individual interviews with residents, alongside documentary analysis and stakeholder interviews. Perceptions of risk and trust in the local polluting industry have fluctuated over the years, with unease never far from the surface as industrial employment has slowly contracted. Yet overall, the picture in 2019 was not too dissimilar from that in 1997: while community–industry relations were strained amidst periodic risk incidents and a sense of decline, a cautious sense of trust in the polluting enterprise had endured, based on a delicate balance of heritage, risk, and recognition. We draw attention to the residents’ careful reckoning with risks over time and the tenacity of social trust as an act of negotiation that took risk into account but also included other important factors such as recognition and reciprocity. Local risk perceptions in Fawley are closely bound up with the residents’ shared industrial heritage and enduring perceptions of Esso as a ‘good neighbour’. Our longitudinal analysis allowed us to reflect on changes over time in Fawley, providing greater temporal depth to the risk perception literature.

Analysis and potential ecological risk assessment of heavy metals in the surface soils collected from various land uses around Shazand Oil Refinery Complex, Arak, Iran

Analysis and potential ecological risk assessment of heavy metals in the surface soils collected from various land uses around Shazand Oil Refinery Complex, Arak, Iran

Prediction of product distribution in the delayed coking of Iranian vacuum residue

The delayed Coker process as an upgrading process has main impact on the productivity of the Refinery Complexes. To determine the impact of different operating conditions on the product yield distribution of the delayed coking process, several experiments were designed and conducted in a prefabricated pilot plant. The experiments were conducted on different Iranian vacuum residues at temperatures ranging from 420°C to 480°C and at atmospheric pressure. Reaction times were within the range of 5-120 minutes. A four lumps kinetic model has been developed based on the experimental results. The lumps—which included Volatile products, coke, feed, and an intermediate phase between coke and feed—were defined to precisely monitor the yield distribution of products throughout the reaction time. The feedstocks utilized were three different vacuum residues and their blends. The mixtures were produced by using different mixing ratios of the three vacuum residues. The Statistical analysis shows that this model has R-squared, RMSE, SSE, and MRE equal to 0.99, 0.022, 0.08, and 3.537%, respectively. This shows that the developed model is sufficiently accurate. The experimental and modeling results in this research reveal that by increasing the temperature, the yield of coke and gas is abated. However, the yield of the distillate is escalated. This investigation illustrates that the production of an intermediate reaction has the highest amount of activation energy in comparison with the other reactions. Also, the results indicate that the production reaction rate of coke has the highest amount in comparison with other reactions.

Real-time refinery optimization with reduced-order fluidized catalytic cracker model and surrogate-based trust region filter method

Since its initial development in the 1980′s, Real-Time Optimization (RTO) has been widely appreciated as an efficient way to optimize process decision variables and improve economic performance of refineries. RTOs consist of nonlinear optimization models with hundreds of thousands of equations, which are built within equation-oriented (EO) modeling platforms. With increasing size and complexity of RTO applications, there is increased demand for improved optimization strategies. To address this demand, surrogate models for complex refinery units have been embedded within the general EO framework for RTO. Moreover, the recent trust region filter (TRF) optimization strategy allows great flexibility in the choice of surrogates, while ensuring convergence to the optimum of the rigorous RTO model. This study considers this approach for a real-world refinery. The Petrobras S.A. RECAP unit in Mauá, Brazil runs an RTO refinery model with an Aspen RTO optimizer to maximize the profit within two hour cycles. To reduce the computational burden, we embed a reduced model (RM) to replace the detailed (truth) model for the residue fluid catalytic cracking (RFCC) unit, and implement a TRF optimization strategy. The TRF driver is written in Python and integrates with the RFCC truth model, the Aspen-EO RECAP model, and the Aspen RTO optimizer. The approach is illustrated on three real-world scenarios in order to demonstrate the effectiveness and efficiency of this RM-based optimization strategy.

Analysis of Tsunami Disaster Risk for a Petroleum Refinery Plant at Tsunami Prone Area

A Petroleum Refinery Plant is located in the tsunami prone area at the southern coast of Central Java, Indonesia. The potential mega thrust earthquake, along subduction zone of southern coast of Java, has been identified to have moment magnitude as maximum as Mw = 8.7. The worst scenario due to this earthquake will potentially generate 5.3m to 8.6m tsunami height along the coast within 30 minutes and will inundate one to two kilometres inland of the refinery complex. In this regard, a comprehensive investigation on potential tsunami hazard, level of vulnerability, and tsunami risk potential were carried out. The investigation includes collection and analysis data of detailed topography, bathymetry, land covering and land use, availability of protective structure as well as disaster contingency plan, field ground check data verification, awareness questionnaire, etc. The investigation output includes numerical tsunami inundation simulation, tsunami hazard index, vulnerability index, capacity index, and tsunami risk index for all area of refinery unit. It is concluded that: 1) the main location of refinery complex with considerable numbers of tanks is vulnerable to high tsunami hazard index, and 2) the capacity index in all area are mostly between low to mid-level.