Roof Tanks Research Articles

ONLINE FIXED TANK VOLATILE ORGANIC CONTENT QUANTIFICATION USING MACHINE LEARNING

Tank emission calculation is typically performed offline, and manual data gathering from various tanks could be a timely and inefficient task. This paper presents iCON’s first principal process simulation software to perform tank emission quantification by leveraging its extensive database of all process simulation models and chemical components’ physical properties. Hence, a lot of operation cost is saved by eliminating the need for inventory sampling activity for each tank. This paper also will discuss online tank emission work processes to make them sustainable. iCON Tank Emission complies with the United States Environmental Protection Agency (USEPA) Compilation of Air Pollutant Emission Factors (AP-42) Fifth Edition Chapter 7 Liquid Storage Tanks that covers fixed roof tanks (vertical and horizontal) and floating roof tanks (internal, external, and domed) with a respective combination of the roof, shell, rim seal, fittings and breather vent settings. It is also linked to the monthly Malaysian Climate Condition covering domestic municipals’ temperature (minimum and maximum), Solar Irradiance Factor, and wind speed that improve the tank emission calculation accuracy. iCON Tank Emission lets users calculate thousands of tank emissions simultaneously by using iCON Machine Learning feature and displays the monthly and yearly summary reports for report standardisation among multiple business units. The simulation convergence time is instantaneous, making it time efficient for HSE engineers to perform strict monthly calculations and reporting online. Case studies and whatif scenarios could also be run to reduce tank emission via the introduction of vapour recovery and optimising tank mechanical parameters, i.e., type of rim seal, colour, and fittings selection. iCON Online Tank Emission links the iCON model with real-time plant information data for real-time tank emission calculation, transparent to management and regulators. The findings from this compositional first principle thermodynamic base tank emission simulation study are considered more efficient, faster, and cheaper than the conventional method.

Application Analysis of Oil and Gas Safety Active Protection System in the Sealing of Large External Floating Roof Tanks

In the use of large-scale external floating roof storage tanks, the application of sealing performance is very critical, which is related to the safety of storage tanks to a certain extent. In the practical application of storage tanks, it is found that the main cause of fire problems in large oil storage tanks with external floating roof is caused by sealing problems. Therefore, it is very important to deal with the sealing performance of large-scale external floating roof tanks when they are put into use. In this paper, the active safety protection system for large-scale external floating roof storage tanks is analyzed, and its application is analyzed, including its structural design, functional design and working principle design, and its specific application in XX project is put forward.

Analytical calculation of lightning strike probability for floating roof tanks

Fire hazard studies have shown that lightning is a major threat to petroleum storage facilities, especially floating roof tanks (FRT) due to the risk of lightning-induced fires which may ultimately result in tank boil over, and an increased risk of the fire spreading to adjoining facilities. Lightning is a natural occurrence with scientific attributes that have been studied for decades towards mitigating lightning-related hazards. The probability of a direct lightning strike to various points on a FRT can be estimated by applying the dynamic electro-geometrical model (DEGM) using numerical techniques, and this provides information on the high-risk lightning-strike points on the FRT. This numerical approach involves surface discretization resulting in millions of meshed points in some cases, both on the structure and the surrounding space. This requires a lot of computer resources, and the simulation is slow to compute. In this study, simple and easy to compute equations were developed and hereby proposed as alternatives to numerical DEGM by applying analytical equations directly from first principles. The result confirms the susceptibility of the shell’s rim region to direct lightning strikes with 90.61% probability of a direct strike for a 20 m high tank and 88.58% for a 15 m high tank with 60 m in diameter. The results show close approximations to the numerical model and also reveals the effects of the discretization size on the accuracy of the numerical approach, while also reducing the computation time from several hours to a few minutes.

Supply Chain Analysis for Water and Sanitation Technology Research Project (Case Study in Morotai Island, North Maluku Province)

Morotai’s sanitation and clean water technology is covering sanitation technology (bio filter, sanitary pond) and clean water (SPC, Reserve Osmose). This technology is ready to be applied in Daruba Pantai, Morotai, North Maluku and all of its technology originated from Java. Research problem’s focus on supply chain. Research objectives eager to see to what extent the supply chain of sanitation and clean water technology, from the technology producers which are mostly located in Java and the application location is in Morotai. The study of Supply Chain in Clean Water and Sanitation Technology Implementation using an applied based research approach. This study refers to scientific research and attempt to solve practical problems. The result of this study, any supply chain for four technologies in Morotai. The results consist of identifying supply chain components, determining network dimension structure that consists of three types dimension, determining type of business chain, and mapping supply chain. For the sanitation technology (bio filter), there are six certified bio filter suppliers and one of them will be selected as the supplier of the construction project in Morotai area. At the sanitary ponds technology, the constituent component/material can be retrieved from local suppliers in Morotai. For Simple Water Management Installation-Quick Sand Filter/SPC, the technology constituent component itself comprises of ground water tank, pump, roof tank, and Quick Sand Filter (made of fibre). This material is brought from the supplier named CV. Lusika in Bandung. Then, the RO technology constituent component is quite many comprising of water inlet valve, pre-filter, RO membrane, post-filter, automatic inspection valves, flow blockers, reservoir, faucet, and exhaust pipe. RO system unit is brought from the supplier called PT. Zeofilt Water Treatment that located in Bandung.

Prediction of Maximum Pressure at the Roofs of Rectangular Water Tanks Subjected to Harmonic Base Excitation Using the Multi-Gene Genetic Programming Method

Liquid storage tanks subjected to base excitation can cause large impact forces on the tank roof, which can lead to structural damage as well as economic and environmental losses. The use of artificial intelligence in solving engineering problems is becoming popular in various research fields, and the Genetic Programming (GP) method is receiving more attention in recent years as a regression tool and also as an approach for finding empirical expressions between the data. In this study, an OpenFOAM numerical model that was validated by the authors in a previous study is used to simulate various tank sizes with different liquid heights. The tanks are excited in three different orientations with harmonic sinusoidal loadings. The excitation frequencies are chosen as equal to the tanks’ natural frequencies so that they would be subject to a resonance condition. The maximum pressure in each case is recorded and made dimensionless; then, using Multi-Gene Genetic Programming (MGGP) methods, a relationship between the dimensionless maximum pressure and dimensionless liquid height is acquired. Finally, some error measurements are calculated, and the sensitivity and uncertainty of the proposed equation are analyzed.

Analysis of hidden safety hazards and treatment suggestions when the floating roof of oil storage tanks falls to the bottom

In the actual production and operation of enterprises, it is sometimes inevitable that the floating roof will fall to the bottom. This paper calculates the explosion limit of the mixture of oil gas under the floating roof, and confirms that the concentration of oil gas will be within the explosion limit under certain circumstances. Through the monitoring and analysis of the oil-gas mixing space below the floating roof, corresponding control measures are proposed to deal with the potential safety hazards of the floating plate falling to the bottom.

SELEKSI DESAIN ROOF TANK CSTR UNTUK PLANT BIOGAS POME SETARA 700KW

Indonesia is the largest palm oil producer in the world. In the process of its processing into Crude PalmOil (CPO), the palm oil processing industry produces various types of waste, including liquid wasteknown as Palm Oil Mill Effluent (POME). POME contains organic matter that is high enough so it mustbe processed before being discarded into the environment. During this time, POME is treated usinganaerobic ponds which are quite large and produce metana gas. Metanae gas has a high level ofemissions, but it potential to become an energy source if it is utilized. Therefore, BPPT in collaborationwith PT. Perkebunan Nusantara 5 built a biogas production pilot plant from POME equivalent to 700kWfor boiler fuel at PKS Sei Pagar, Kampar Regency, Riau Province. The process of converting POMEinto biogas uses Continuous Stirred Tank Reactor (CSTR) technology. The research aims to choosethe best roof tank design for CSTR. The method used is the Pahl and Beitz method and the House ofQuality. The result of the study are the best specification planning data, which is 1400 mm in diameterand the construction site position at a height of 15350 mm from the bottom of the reactor, with use aninternal support column, with the best variant chosen is the fixed roof type with dome shape.

Determining the emission rates of volatile organic compounds and modeling their dispersion from the petroleum and chemical storage tanks of the largest oil terminal in the southwest of Iran

This study aimed to investigate the air pollution caused by volatile organic compounds (VOCs) with an emphasis on benzene, toluene, ethylbenzene, and xylene (BTEX). Due to surface evaporation from the storage tanks of the largest petroleum and chemical product terminal in the export port of the southwestern Iran, the field measurements of the emission sources were performed using the TANKs 4.0.9d software, and VOC emission modeling was performed using the PHAST software. Among 36 point sources (32 external floating roof tanks and four internal floating roof tanks), the emission rates of the VOCs of the storage tanks were determined using the TANKs 4.0.9d software in the area of 3.8 km2 during 12 months (March 2017-January 2018). The highest rate of VOC emissions from the tanks was observed in July, with the highest temperature and wind speed in the region. According to the results, the total emission rate of the VOCs from the storage tanks was 881.74 ton/year, and the highest emission rate was observed in the external floating roof tanks (865.7 ton/year; 98.18%). The contribution of the internal floating roof tanks was 16.04 ton/year (1.81%), and the highest and lowest VOC emission rates in the export port were observed in the light naphtha tank No. 67 and jet naphtha storage tank (56.73 and 4.18 ton/year), respectively. In addition, the highest and lowest BTEX emission rates from the storage tanks were observed in the gasoline tank No. 62 and jet naphtha tanks No. 93 and 94 (0.37 and 0.05 ton/year), respectively.

Technology Focus: Production and Facilities (December 2020)

The notion of reducing our environmental footprint, minimizing leaks and spillages, and identifying operational efficiencies is nothing new. We have been addressing these issues for years. Sustainability, however, has gained a higher profile recently, especially since the 2015 United Nations Framework Convention on Climate Change accord and the evolution of alternative energies. It came, therefore, as a pleasant surprise to review an extraordinary wealth of well-written papers relating not only to this topic, but to all manner of fascinating engineering issues. Let me back up a bit. For 6 years, I have provided commentary concerning matters relating to reservoir simulation. This was often illuminating, but my primary interest has always been in full-field modeling: coupling our models for flow in porous media, wellbore, network, and to facilities. I firmly believe that unified full-field modeling can furnish benefits both operationally and economically. In accepting the challenge to write this, however, I did not expect to encounter the extraordinary breadth of topics covered. Saying that, one clear thread did emerge from the articles reviewed - namely reliability, emissions control, and energy saving and monitoring, all of which relate to sustainability in one way or another. Novel methods for valve- failure prediction, pipeline coatings, floating storage tank roof optimization, and the use of drones (from spray painting to surveillance) along with robots for unmanned installations were all topics represented in the papers provided me. Paper SPE 198165 is an informative overview of alternative fuels and how these may affect Middle East production; however, this should appeal to a wider readership because it reviews alternative energies nicely. Paper IPTC 19775 provides a means to better quantify separator shrinkage, which can result in errors in stock-tank rates up to 20% (essential if one is to quantify unit energy consumption accurately). Paper SPE 197759 proposes methods for energy savings. These papers represent but a small sample of a broader swath of articles from the past year relating to this catch-all term “sustainability.” Recommended additional reading at OnePetro: www.onepetro.org. SPE 197753 Parametric Study on Wind Fatigue Life of Long Span Flare-Boom Based on Directional Input Parameters to Harris Wind Spectra and Selection of Wind Blocks by Sachin Samant, National Petroleum Construction Company, et al. SPE 198133 Internal Corrosion Severity Ranking of Crude Oil Pipelines by Amer Jaragh, Kuwait Oil Company, et al. SPE 197620 Ground Robotics Enabler for Normally Unattended Installations by Jean-Michel Munoz, Total, et al.

Nitrogen Protection as Anticorrosion and Fireproofing Measure in the Use of Sour Crude Oil Storage Tanks

The results of using a nitrogen protection system for 15 years in a sour crude oil storage park equipped with Hazmat class II and III vertical storage tanks with a stationary roof without pontoons are analyzed. Under nitrogen protection conditions, the rate of localized corrosion of the inner surface of the roof of raw and commercial crude oil storage tanks is 0.013–0.015 mm/year, which is ∼100 times lower than the rate of corrosion under natural gas phase conditions inside the tank. Continuous operation of the nitrogen protection system ensures fire and explosion safety of the tanks. Interruptions in the nitrogen protection do not have any practical effect on the efficiency of through perforation of the roof until the end of the regulated service life of the tanks, but increase fire and explosion hazard due to the formation of pyrophoric corrosion deposits.

Failure Analysis of the Top Reticulated Shell Structure of a 20,000 Cubic Meter Floating Roof Storage Tank

The single-layer spherical reticulated shell structure is used as the fixed roof of a 20000 m3 internal floating roof tank. In the process of inspection and maintenance, the reticulated shell collapsed. In this paper, the strength, stiffness and stability of the design structure of the tank roof reticulated shell are calculated based on the finite element model, and the weak points of the shell structure are revealed, and the failure causes of the shell structure are comprehensively analyzed.

Research on axial temperature distribution of annular pool fires of floating roof tanks

Research on axial temperature distribution of annular pool fires of floating roof tanks

The time-to-failure assessment of large crude oil storage tank exposed to pool fire

In large crude oil tank farm, fire is a major primary event in domino effects according to past accidents. The quantitative risk assessment of domino fire accident is a key issue for the accident prevention of large storage tank farm. The most widely used equation for the estimation of the tank's time to failure (TTF) exposed to pool fire is not suitable for 100,000 m3 external floating roof tank. The purpose of this study is to establish simplified models for the calculation of the tank TTF with respect to heat radiation intensity, filling level and the availability of safety protections under different fire conditions. The finite element transient heat transfer modeling of 100,000 m3 external floating roof tank in the case of fire scenarios was performed. The quantitative assessment of safety protection performance in delaying the tank failure under fire conditions was performed according to the simulation results. The application of the TTF equation to case-studies of crude oil tank farm showed the importance of safety protection for the prevention and mitigation of the domino effect. The TTF model provides a basis to the risk management and emergency response in large tank farm.

A calculation method for simulation and evaluation of oil vapor diffusion and breathing loss in a dome roof tank subjected to the solar radiation

The dome roof tank (DRT) is always a main equipment for oil products storage. However, the mechanism of the heat and mass transfer for the oil vapor-air in the tank gas space remains unclear when the DRT is subjected to the solar radiation. Therefore, by considering storage conditions (e.g., the solar radiation intensity and liquid height) and taking n-hexane as a representative of light oils, and based on the Fluent software and user-defined functions (UDFs) programming, a two-dimensional calculation method and the relevant theoretical model were numerically developed to simulate and reveal the transfer mechanism under the complex storage process. Meanwhile, the feasibility of the model was verified by a self-built experimental platform for the DRT evaporation loss investigation. Under the solar radiation to a 1000 m3 DRT, the simulation results show: (1) The gas space temperature distribution can be accurately calculated, and the average temperature decreases with increasing liquid level; (2) There is a distinct counterclockwise eddy and an evident velocity boundary layer close to the wall and roof of the gas space, and the maximal gas velocity is within 0.08–0.49 m s−1, which is closely related with the storage liquid height and time; (3) The vapor concentration in the gas space increases from top to bottom with an obvious high-concentration layer near the liquid surface, and the average concentration increases with increasing liquid level and storage time; (4) The static breathing losses increase positively with the liquid level. The mean daily loss rates for n-hexane are approximately 7.37 g t−1, 20.9 g t−1, and 6.36 g t−1 for the spring equinox, summer solstice, and winter solstice, respectively. Further, the year-mean daily loss rates are about 11.5 g t−1, and 20.1 g t−1 for n-hexane and gasoline, respectively, and the correspondingly the total loss rates for a year are about 4.2 kg t−1 and 7.35 kg t−1. The research results can provide important theoretical support and design reference for reducing the breathing loss and improving the enterprise management level.

Analysis of Natech risk induced by lightning strikes in floating roof tanks based on the Bayesian network model

AbstractBased on the Bayesian network, a risk assessment model of Natech was established to assess the risks associated with lightning. Based on existing research results and expert analyses, a causal relationship between different parameters was constructed, and the conditional probability values of nodes were determined. This Natech risk assessment model was used to predict and analyze the fire explosion of inner floating roof tanks caused by lightning. The results showed that Natech risk assessment models by the Bayesian network could clearly express the direct causality of risk factors and perform both predictive and diagnostic analyses.

EVALUATION OF CLEAN WATER SUPPLY SYSTEMS OF DARUL HIKMAH MOSQUE IN POLITEKNIK NEGERI SEMARANG

Darul Hikmah Mosque is a building located inside Politeknik Negeri Semarang as a place of worship for all campus residents, and people who live around the area. The prayer activity is preceded by the Wudu. In order for Wudu to be carried out perfectly, sufficient quantities of water are needed. The lack of pressure and discharge of Wudu tap water, when used simultaneously, becomes a constraint that is the water pressure decreases. The purpose of this study is to determine the factors causing the lack of water discharge or pressure as required in SNI 03-7065-2005. The research method is quantitative descriptive by evaluating the performance of the existing water supply system and using a discrepancy model by comparing the evaluation results with existing data to find discrepancies. Evaluation results indicate that the factors that cause the lack of water pressure are the roof tank height is less than ideal for water distribution with gravitational power, and the volume of available water is not sufficient

Emissions of volatile hydrocarbons from floating roof tanks and their local dispersion: Considerations for normal operation and in case of damage

This work investigates the release and dispersion of volatile organic hydrocarbons, which may escape from external floating roof tanks (EFRT) during normal operation or in case of damage. The dispersion will be described using CFD simulations in close range of the EFRT where hazardous areas are assigned. The aim of this work is to investigate which events can lead to emissions in dangerous quantities and to estimate the corresponding likelihood with regard to explosion protection. An emission in hazardous amount is present if the lower explosion limit has been exceeded and if the extent of this emission is not too low. It is discussed in particular whether the used zoning of potentially explosive areas is conservative or over-conservative.

On the modal response of an instrumented steel water-storage tank including soil-structure interaction

The modal response of liquid-storage steel tanks and the associated prevailing frequencies in the horizontal impulsive mode of vibration are explored by means of earthquake recordings. To this end, a well-documented case study is employed, referring to an instrumented steel cylindrical tank which is a property of the HEL.PE. Oil Company in the Kalochori area, west of Thessaloniki in Northern Greece. The 28.5m-diameter tank has a self-supporting dome roof fixed to the tank walls and it is partially filled with water, corresponding to a ratio of the liquid free surface height to the tank's radius (H/R) at 0.74. Two accelerometric stations are mounted close to the center of the tank roof and on the ground surface at free-field conditions. Seventy four (74) acceleration records from low-intensity earthquake motions are processed to identify the fundamental frequencies of the tank and of the foundation soil from pertinent transfer functions in the frequency domain. The experimental findings are compared with predictions from theoretical formulae recommended by seismic design codes for fixed-base and flexibly-supported tanks, thus allowing the assessment of soil-structure interaction effects on the fundamental period of the tank. A simplified three-dimensional finite-element model of the fluid-tank system resting on flexible supports is also analyzed to provide further insight on the recorded response, as affected by critical structural features of the tank. Results highlight a dominant rigid-body mode which is associated to the lateral fundamental period of the flexibly-supported system, in agreement with relevant code provisions for tanks with H/R below unity.

The challenge of achieving safely managed drinking water supply on San Cristobal island, Galápagos.

Achievement of United Nations Sustainable Development Goal 6.1 centers on the availability of a safely managed drinking water source for all. However, meeting the criteria for this goal is challenging on island systems and elsewhere with limited freshwater supplies. We measured microbial and chemical water quality over three years on San Cristobal Island, Galapagos, an island with limited freshwater supply, necessitating use of cisterns or roof tanks to ensure water availability in households. Our results showed that the municipal water treatment plants generally produced high quality drinking water but detection of Escherichia coli in 2-30% of post-treatment distribution samples suggests contamination and/or regrowth during distribution and storage. Linear regression revealed a modest, negative relationship between residual chlorine and microbial concentrations in drinking water samples, while 24-h antecedent rainfall only slightly increased microbial counts. Taken together, our results underscore the challenge of providing a safely managed drinking water source where limited freshwater quantities result in intermittent flow and require storage at the household level. Efforts to meet sustainable development goals for island systems will likely need to consider water availability for any treatment technologies or programs aimed at meeting water quality goals.

Analysis of Cause of Fire and Explosion in Internal Floating Roof Tank: Focusing on Fire and Explosion Accidents at the OO Oil Pipeline Corporation

This study aims to maintain the safety of an outdoor storage tank through the fundamental case analysis of explosion and fire accidents in the storage tank. We consider an accident caused by the explosion of fire inside the tank, as a result of the gradual spreading of the residual fire generated by wind lamps flying off a workplace in the storage tank yard. To determine the cause of the accident, atmospheric diffusion conditions were derived through CCTV image analysis, and the wind direction was analyzed using computational fluid dynamics. Additionally, the amount of oil vapor inside the tank when the floating roof was at the lowest position, and the behavior of the vapor inside the tank when the floating roof was at the highest position were investigated. If the cause of the explosion in the storage tank is identified and the level of the storage tank is maintained below the internal floating roof, dangerous liquid fills the storage tank, and the vapor in the space may stagnate on the internal floating roof. We intend to improve the operation procedure such that the level of the storage tank is not under the Pontoon support, as well as provide measures to prevent flames from entering the storage tank by installing a flame arrester in the open vent of the tank.