Tank Cleaning Research Articles

Disposal of Pipeline Residues from Coke-Oven Gas Transportation

The solid residue and condensate from the pipeline transportation of coke-oven gas are investigated. Approaches to disposal of the residue are considered: pyrolysis in coking batch; furnace incineration at thermal power plants; addition to coal tar; and utilization together with heavy tars from the cleaning of tar storage tanks. The residue contains up to 69.4% naphthalene. A technology is proposed for the utilization of solid residue and condensate from the transportation of coke-oven gas.

Frequency of extended-spectrum β-lactamase (ESBL)– and AmpC β-lactamase–producing Enterobacteriaceae in a cheese production process

The aim of this study was to investigate the extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase activities of Enterobacteriaceae isolated from raw milk and cheese production line and to determine the probability of transmitting these bacteria to consumers. One hundred seventy-three samples from raw milk and cheese production lines were analyzed; 64 isolates were confirmed as Enterobacteriaceae. Sixteen of 64 isolates (25%) were resistant to at least one cephalosporin according to European Committee on Antimicrobial Susceptibility Testing Standards (EUCAST) and Clinical and Laboratory Standards Institute criteria. Seven of the 16 resistant isolates (43.75%) had confirmed ESBL activity. Additionally, phenotypic AmpC β-lactamase activity was observed in 31 (48.44%) of 64 Enterobacteriaceae isolates and confirmed in 27 of the 31 strains (89.1%). Overall, 3 isolates showed both ESBL activity and AmpC resistance, 28 isolates were only AmpC resistant, and 5 isolates had ESBL activity alone. Of the 173 samples, the proportions of samples that contained ESBL- and AmpC-producing isolates were 4.64 and 15.6%, respectively. Five of the ESBL-positive isolates (62.5%) and 11 of the AmpC-positive isolates (40.7%) were obtained from bulk milk tanks; therefore, the bulk tank plays a very important role in the spread of antibiotic-resistant bacteria. Periodic cleaning and maintenance of bulk tanks should be performed and recorded. Effective food safety and hygiene practices should significantly reduce cross-contamination in dairy plants.

Performances in Tank Cleaning

Performances in Tank Cleaning

Ensuring Safe and Reliable Cleaning of Asphaltene Deposits Inside Tanks at Fuel-Oriented Petroleum Refineries

The purpose of this study is to improve the operational reliability of oil storage tanks and storage equipment at petroleum refineries by extending their mean time to repair (MTTR). The principal methods for studying the problem are the simulation experiment and the statistical processing of the quantitative results of the study. Based on the results of the wall thickness test for the first ring of an oil storage tank, the authors made a case for a regular removal of deposits from the tank walls. The suggested system for tackling the asphaltene deposits (ADs) consists in treating the deposits with a petroleum product heated to their melting point. The optimal solution temperature was chosen based on the results of the tests run to observe the impact of heat on the deposits and establish their melting temperature. A series of experiments were undertaken to identify the optimal composition of heating oil for treating ADs. The methods proposed in the study can be used to build a mathematical model of an AD removal unit for cleaning oil storage tanks, to calculate the operational characteristics of the equipment, and to design a process flow diagram that can be used at fuel-oriented petroleum refineries.

Production and characterization of a new biosurfactant from Pseudomonas cepacia grown in low-cost fermentative medium and its application in the oil industry

The production of a biosurfactant by Pseudomonas cepacia CCT6659 was studied in a low-cost medium formulated with 2% waste frying oil, 3% corn steep liquor and 0.2% NaNO3 for 60 hs at 28 °C and 250 rpm. Biosurfactant production was growth associated, as indicated by the growth and biosurfactant production kinetics. The surface tension of the medium was reduced from 65 mN/m to less than 25.5 mN/m. The properties of the biosurfactant that was separated by acid precipitation and solvent extraction were investigated and its critical micelle concentration was determined as 600 mg/L. Preliminary chemical characterization revealed the anionic nature of the biosurfactant. The biosurfactant was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1 H NMR) and gas chromatography and mass spectroscopy (CG-MS). Biosurfactant demonstrated good surface tension reduction capacity and emulsifying activity with motor oil (up to 90%). The biosurfactant also demonstrated stability during exposure to high temperatures (up to 120 °C for 15 min), high salinity (12% NaCl) and a wide pH range (2–12). The crude biosurfactant was not toxic to the microcrustacean Artemia salina or two Brassica oleracea plant species. The crude biosurfactant was effective at recovering up to 75% of the residual oil from sand samples, at displacing oil (81%) and recovering up to 90% of motor oil from the walls of beakers. These results indicate the potential value of this biosurfactant for application in the oil industry, especially in enhanced oil recovery, tank cleaning and the bioremediation of spills at sea and soil.

Valuing cargo flexibility in oil transportation

ABSTRACTThe seaborne oil transportation market is served by two main types of vessels—crude oil tankers and product tankers. Product tankers are designed to move refined oil products, yet they can also opportunistically carry ‘dirty’ products such as crude and heavy fuel oil, subject to the cost of tank cleaning when re-entering the clean products trade. We apply an entry-exit real option model with a stochastic freight rate differential to derive optimal triggers for switching between the two cargo types and estimate the value of the switching option. We show that the value of active switching has grown over time, and generally exceeds the additional construction cost of a product tanker. Our findings are important both from a practical point of view and for our understanding of market integration in the tanker freight market. Specifically, shipowners can use our model as a basis for optimizing chartering policy for clean product tankers. We also show that there are periods where the dirty market is persistently stronger, and discuss the possible reasons for such apparent inefficiencies.

Occupational Noise Levels in Two Fish Rearing Buildings at an Aquaculture Facility

Occupational noise is commonly encountered during aquaculture. This study documented noise levels in two buildings at a production fish hatchery, a tank room with 32, 1.8-m diameter tanks, and a rearing pavilion with 32, 6.1-m diameter tanks. With water flowing to all of the tanks in the tank room, mean noise levels were 68.4 dB, and significantly increased to 73.0 dB during tank cleaning and 73.2 dB when intermittent automatic feeders were running. The highest tank room values of 77.1 dB were recorded directly next to individual tanks during cleaning. With water flowing to all of the tanks in the rearing pavilion, mean noise levels were 70.2 dB. A significant increase to 76.1 dB was observed when the pavilion tanks were being power washed, with the highest value of 83.2 dB recorded immediately adjacent to the power washer. Although none of the noise levels exceeded regulatory limits, the use of techniques to reduce occupational noise in aquaculture environments is recommended.

Fireproof cleaning of tanks from oil sediments

Fireproof cleaning of tanks from oil sediments

新タンククリーニングシステム（ＢＬＡＢＯシステム）の概要と適用事例

新タンククリーニングシステム（ＢＬＡＢＯシステム）の概要と適用事例

Ichthyophthirius multifiliis (White Spot) Infections in Fish

Ichthyophthirius multifiliis (Ich) is a protozoan parasite that can cause severe losses in aquaculture and aquariums. It is introduced via new fish, substrates, plants, or equipment. Preventive measures include quarantining and treating new fish, holding plants without fish, and disinfecting decorations. Ich can cause rapid, high mortality among fish. Immediate treatment is necessary due to its fast reproduction. Since only the infective theront stage is susceptible to treatment, repeated treatments or prolonged salt use are required. Daily tank cleaning helps remove the parasite. Survivors can carry the parasite and reinfect others. This document is about how effective management and biosecurity practices, including quick treatment and multiple treatments during outbreaks, can help to control Ich and minimize economic losses. First published March 1991.

Cleaning vessel walls by moving water jets: Simple models and supporting experiments

Impinging liquid jets are widely used in cleaning-in-place operations to remove product residues and soil layers from vessel walls. The model for adhesive removal of soiling layers by coherent impinging water jets presented by Wilson et al. (2014, Chem. Eng. Sci., Vol. 109, 183–196) is revisited and is applied to a series of cases related to tank and vessel cleaning, including the case of a strong (hard to remove) soil; the case where the jet strikes the wall at an oblique angle; and where the point of jet impact moves across the surface. A subset of the results shows good agreement with new and previously published experimental data. A new analysis is presented for calculating the shape of the region cleared of soil by the point of jet impact moving around, or up and down a surface, which allows the resources (time, liquid, and energy) required to clean a cylindrical vessel to be estimated. Selected jet paths and nozzle motion patterns are compared in a case study which illustrates the potential for designing a cleaning programme. The models make several simplifications and theoretical developments required to generate more accurate results are identified.

Flow pattern and cleaning performance of a stationary liquid jet operating at conditions relevant for industrial tank cleaning

Cleaning of processing tanks by impinging liquid jets is common practice in the food and biotechnology sectors. However, satisfactory prediction of the cleaning performance of such jets has so far only been achieved in small scale experiments. In the present work, cleaning with a horizontal water jet was studied using a 19m3 tank and settings applicable to industrial operations; nozzle internal diameters, dN, of 2–5.5mm, cleaning distances, L, of 80–2490mm, and flow rates, Q, of 0.05–3.0m3h−1. Experimental data and model predictions of the behaviour of the jet when striking an unsoiled surface showed reasonable agreement for a nozzle with dN=2mm at small cleaning distances (L 80 and 200mm). At greater dN and cleaning distances there was poorer agreement, which was attributed to jet break-up and splatter.Similar observations were made when cleaning a surface soiled with white petroleum jelly. The evolution of the cleaned area was predicted reasonably well for experiments with dN=2mm, L=80mm, and soil layer thicknesses of 0.25–1.49mm. For longer cleaning distances and larger dN only the initial stages of cleaning could be modelled, because jet break-up introduced complexities and momentum losses not accounted for in the mathematical models. The effects of jet break-up can partly be accommodated, in practice, by correcting the jet flow rate for these momentum losses.

Structural Complexity Improves the Rearing Performance of Rainbow Trout in Circular Tanks

AbstractWhile structural complexity has been used extensively during hatchery rearing in an attempt to improve poststocking survival, the potential impact of this complexity on hatchery rearing performance has largely been ignored. This study examined the growth and condition of juvenile Rainbow Trout Oncorhynchus mykiss reared in nearly fully covered circular tanks containing nine vertically oriented round aluminum rods (structurally complex) compared with that of trout reared in almost fully covered tanks with no rods (control) at two water velocities (2.0 body length (BL)/s and 2.75 BL/s). After 51 days, total tank weight gain was significantly higher in the structurally complex tanks than in the control tanks, regardless of water velocity. The feed conversion ratio was also significantly better in the structurally complex tanks [mean (SD) 1.25 (0.10)] than in the control tanks [1.66 (0.41)]. There were no significant differences in hepatosomatic index, splenosomatic index, and viscerosomatic index between the fish from the structurally complex and the control tanks. Total tank weight gain was significantly higher and the feed conversion ratio significantly lower in the lower water velocity tanks than in the higher water velocity tanks. These results indicate that vertically oriented aluminum rods can be used to increase structural complexity and improve Rainbow Trout rearing performance in circular rearing tanks, with minimal effects on regular tank cleaning.

KNOWLEDGE ON ADJUVANT PROPERTIES, DISPOSAL OF PESTICIDERESIDUES AND SPRAY DRIFT OCCURRENCE IN THE STATE OF MATO GROSSO

ABSTRACT This paper aimed at investigating the knowledge level of people working on pesticide spraying activities concerning spray adjuvant properties, as well as collecting information on disposal locations for residues from internal spray tank cleaning, and finally the understanding of pesticide spray drift occurrence in the state of Mato Grosso, Brazil. The information was gathered through a questionnaire answered by participants of a rural extension program in application technology located in nineteen grain and fiber producing regions of Mato Grosso state. Among the mentioned adjuvants, 49.0% belonged to the mineral oil class and 17.9% of participants did not know the functions performed by such products. In addition, 58.5% of the participants discarded residues into the field. Among the participants who answered the question about spray drift occurrence causes, 54.1% indicated problems relating to inadequate weather conditions. In conclusion, there is a lack of knowledge on adjuvant functions, besides of inappropriate residue disposal in the state of Mato Grosso. Spray drift was referred as a problem; however, most of participants were not able to discuss the causes of these losses.

Modern efficient methods of steel vertical oil tanks clean-up

The legislative base of the Russian Federation operating in the field of operation of tanks and tank parks is considered, and consecutive stages of technological process of cleaning of vertical steel tanks from oil ground deposits are presented. In work shortcomings of existing most widespread electromechanical mixers are described when using a hydraulic method of removal and prevention of formation of ground deposits in tanks with oil and oil products. For the purpose of increase of efficiency, reliability and decrease in power consumption of washout of oil ground deposits in tanks the new design of system of funneled washout and prevention of formation of deposits is offered.

Waterborne diseases classification and relationship with social-environmental factors in Florianópolis city - Southern Brazil.

This study aimed to investigate and classify the occurrence of waterborne diseases in Florianópolis city, Santa Catarina State, Southern Brazil and to correlate these diseases with the following social-environmental indicators of the local population: type of water supply, adequate collection and sewage treatment, areas of flooding and domestic water tank cleaning. Reports of outpatients were analyzed for surveillance of waterborne diseases during the period of 2002 to 2009. Waterborne diseases were classified into four groups: Group A: diarrheal diseases; Group B: parasitological diseases; Group C: skin diseases and Group D: eye diseases. The diarrheal, parasitological and skin diseases were the most frequently reported. Waterborne diseases belonging to Group A in all sites were correlated with other waterborne diseases groups, which can be an indicator of the circulation of other waterborne diseases. Regarding the social-environmental indicators assessed, the most correlated with waterborne diseases were the origin and quality of the water supply, followed by inadequate collection and treatment of sewage, frequent flooding, and finally the lack of cleanliness of the water reservoir. The results highlight the need for policies aiming for improvement of the sanitation service in the maintenance of human, animal and environmental health.

Near-Infrared Spectroscopy Analysis of Heavy Fuel Oils Using a New Diffusing Support.

The characterization of heavy fuel oils (HFOs), used as fuel for boats, requires the analysis of various properties that are essential for engine optimization and pollution control. For some time, near-infrared (NIR) spectroscopy combined with chemometric treatment of the spectra was used for on-line analysis. This preliminary study included 61 heavy fuels from Europe, America, and Asia with different specifications according to their geographical origin; their refining process; and their physicochemical properties, including density, flash point, viscosity, and sulfur content. We have developed a new method for sampling heavy fuels on a fiberglass cell support. This support offers the advantages of speed, easy implementation, repeatable results, and freedom from problems associated with tank cleaning. Two sample presentations, an integrating sphere and an optical fiber, were used to collect the NIR spectra. A theoretical study of the choice of the value of resolution, scan number, and spectral region was conducted. The best conditions were chosen as a function of the quality of quantitative analysis results on viscosity, sulfur content, flash point, and density. The two collecting methods were compared on the same criteria.

Charge generation associated with liquid spraying in tank cleaning and comparable processes - preliminary experiments

The BG RCI has initiated investigations in order to improve the data basis for assessing the ignition hazard by electrostatic charging processes associated with the spraying of liquids. On the base of preliminary experiments, we established procedures for measurements of electric field strength and charging current in the presence of aerosol particles. Results obtained with three different nozzle types, variation of pressure and with built-in deflecting plate are presented.

Survey of public attitiude towards bottled and tap water quality in the UAE

<div> <p>The United Arab Emirates (UAE) is one of the leading countries in the per capita bottled water consumption. This seems to be in controversy with adherences of local water authorities to stringent municipal water standards. A public survey (n= 891) was conducted to ascertain the perception of people in the country regarding bottled and tap water quality. The survey form was formulated based on the stated preference approach and was furnished in both Arabic and English languages. Some questions in the survey form require rating the quality of tap water and identifying the type of water the respondent drinks. For respondents who usually drink bottled water, they were asked to choose the reason(s) why they usually drink bottled water. Those who drink tap water more often were similarly asked to choose the reason(s) why they prefer tap water to bottled water. The study revealed that a large fraction of the UAE residents classify the quality of tap water as either good or excellent, yet many of them drink bottled water. This could be attributed in part to the high standard of living where the cost of bottled water is considered by the majority of the respondents as affordable. Other influential factors include the belief that bottled water has a better taste and concerns about tap water contamination. The latter may stem from the perception that water is not sufficiently treated or contamination is induced into the water from the distribution system or the in-house storage tanks. The study shows that more people in the UAE will drink tap water if relevant authorities provide information about tap water quality and if regular inspections and cleaning of the in-house storage tanks is conducted.</p> </div> <p> </p>

A methodological extension to human reliability analysis for cargo tank cleaning operation on board chemical tanker ships

This is an article that conducts an empirical human reliability analysis for tank cleaning process on-board chemical tanker ship to enhance safety and operational reliability in maritime industry, providing a methodological extension through the integration of the AHP technique into the HEART approach. The paper provides a methodological development on decision making and human factors via extending a new approach to weight the proportion of the effect for calculating error producing conditions through operations. The model demonstration illustrates that cleaning of residues from hazardous cargoes such as acetic acid has required performing various critical tasks supported with recovery solutions. This research also provides practical insights along with reliability monitoring in ship operational level.