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1

Geographic Information System for Mapping Coastal Inundation Impact to the Sustainability of Agriculture Sector in Pekalongan City, Indonesia

Suharini Erni, Pratiwi Elok Surya, Hanafi Fahrudin

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 3

114--119

EN

Coastal inundation that is getting farther inland year by year has given a serious problem to the sustainability of farming activities in Pekalongan, but it has rarely been exposed more detail to the public. The aim of this research is to investigate the present effects of seawater inundation to the agriculture sector in Pekalongan coastal area. We focused on the study of coastal inundation dynamics, agriculture area reduction and rice production. Time series remote sensing imageries from google earth satellite were used to analyze the seawater run up between 2003 and 2018. This result revealed that the farthest distance of the inundation in 2018 reached 4.4 kilometers from the coastline in the west part of the city. For the last fifteen years, saline water has reduced almost 380 ha of farm land in the coastal area. That phenomenon has contributed to the rice production lost by almost 173 tons/year during 2003 and 2018. This result has showed a critical condition of agriculture sector in study area, thus some mitigation actions become a necessity thing in order to protect our land as well as food security on the next future.

2

Influence of Salinity of Mixing Water Towards Physical and Mechanical Properties of High Strength Concrete

Razak Rafiza Abd, Yen Ng Khai, Abdullah Mohd Mustafa Al Bakri, Yahya Zarina, Mohamed Rosnita, Muthusamy Khairunisa, Jusoh Wan Amizah Wan, Nabiałek Marcin, Jeż Bartłomiej

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 3

1041--1045

EN

Dramatic population and economic growth result in increasing demand for concrete infrastructure, which leads to an increment of freshwater demand and a reduction of freshwater resources. However, freshwater is a finite resource, which means that freshwater will be used up someday in the future when freshwater demand keeps increasing while freshwater resources are limited. Therefore, replacing freshwater with seawater in concrete blending seems potentially beneficial for maintaining the freshwater resources as well as advantageous alternatives to the construction work near the sea. There have been few experimental research on the effect of blending water salt content on the mechanical and physical characteristics of concrete, particularly high-strength concrete. Therefore, a research study on the influence of salt concentration of blending water on the physical and mechanical properties of high-strength concrete is necessary. This study covered the blending water salinity, which varied from 17.5 g/L to 52.5 g/L and was determined on the physical and mechanical properties, including workability, density, compressive strength, and flexural strength. The test results indicate that the use of sea salt in blending water had a slight negative influence on both the workability and the density of high strength concrete. It also indicates that the use of sea salt in blending water had a positive influence on both the compressive strength and the flexural strength of high-strength concrete in an earlystage.

3

Combining multivariate statistical analysis to shed light on distribution and interaction of halogens in two economic ports along Red Sea Coast in Egypt

Zokm Gehan M. El, El-Said Ghada F., El Sayed Abeer A.M.

Oceanologia

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2022

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No. 64 (1)

103--106

EN

Mabahiss Bay and Safaga Bay are two important ports along the Red Sea coast of Egypt. The present study is the first to monitor halogen concentrations in these two ports. Certain halogens (F, Cl, Br and I) in coastal waters and sediments exhibited different behaviors. Fluoride (1.92–8.31 mg/L and 0.34–1.24 mg/g), chloride (20.76–22.68 g/L and 0.38–8.31 mg/g), bromide (95.90–151.84 mg/l and 6.66–50.61 mg/g), and iodide (2.77–39.19 μg/L and 1.71–3.76 μg/g) appeared in the seawater and sediments of Mabahiss Bay, respectively. In Safaga Bay, F, Cl, Br and I yielded ranges of (1.80–10.15 mg/L and 0.14–0.74 mg/g), (21.47–22.57 g/L and 0.68–1.42 mg/g), (15.98–146.51 mg/L and 6.13–74.59 mg/g) in seawater and sediments, respectively. In Mabashis Bay exclusively, the bromide and iodide levels in seawater increased significantly, and the sediments were vice versa. The average fluoride value in the two ports' seawater was higher than that in the unpolluted Mediterranean Sea. In contrast, the average bromide content in Mabahiss Bay seawater exceeded the Mediterranean Sea level. The seawater chloride content of the two ports was within the Mediterranean seawater's value, but the iodide concentration was lower than that of the unpolluted seawater. The application of different multivariate statistical techniques showed that halogen's distribution and halogen's geochemical characteristics control interaction in each region, ground flux, and proximity to human sources.

4

Biodegradation of Crude Oil Spill Using Bacillus Subtilis and Pseudomonas Putida in Sequencing Method

Titah Harmin Sulistiyaning, Pratikno Herman, Purwanti Ipung Fitri, Wardhani Widhowati Kesoema

Journal of Ecological Engineering

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2021

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Vol. 22, nr 11

157--167

EN

Crude oil, otherwise called petroleum, occurs naturally as a complex organic mixture underneath the subsurface. The activities related to its exploration, production, refining, storage and distribution are mostly accompanied with extreme pollution and other hazardous conditions. For these reasons, the need to critically devise the best possible solutions becomes paramount, particularly as regards oil spills. Therefore, the purpose of this research was to determine the efficiency of TPH removal in crude oil using Bacillus Subtilis and Pseudomonas Putida. The sequencing method was applied in a laboratory scale and under artificial seawater media conditions. The total petroleum hydrocarbon (TPH) serves as a significant parameter in detecting crude oil, although the extraction and analysis were conducted with the use of a separator funnel and gas chromatography mass spectrometry (GCMS), respectively. In addition, the simulated seawater media was described as the mineral salt medium (MSM), with 33% salinity. Moreover, five reactors were also employed, including K for control, B for B. subtilis, P for P. putida, BP for B. subtilis and P. putida sequence and PB for P. putida and B. subtilis sequence. The entire treatments obtained the access to two replicate reactors. Furthermore, the bacteria inoculum and crude oil concentration in each unit were estimated at 5% and 10% (v/v), respectively. The results achieved the maximum TPH removal at 66.29% in the PB reactor after 35 days. On the basis of ANOVA reports, no significant variation was observed between the sequential additions of a single bacterial treatment and consortium microbes. In summary, two bacterial species demonstrated high potential to degrade TPH, but predicted an increase in the break down time, as the nutrient or oxygen tends to accelerate the process.

5

Pourbaix diagrams for copper ores processing with seawater

Marín Oscar A., Ordóñez Javier I., Gálvez Edelmira D., Cisternas Luis A.

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 4

625--640

EN

Decreases in the copper grade, waste disposal, energy supply, and water scarcity are some of the most critical challenges for the copper mining industries. One of the alternatives to counteract the water scarcity is the use of seawater, whether raw, partially desalinated, or desalinated. The use of seawater implies the generation of several compounds as a result of the interaction of ions in waters and ores. For this reason, it is required a greater understanding of these compounds generated on mineral processing, being Pourbaix diagrams used to estimate the possible compounds that will be formed in an aqueous medium for a given metal ore. In this paper, the effect of temperature, salinity, and Cu-concentration on the stability of the copper-solid species was investigated by constructing Pourbaix diagrams for different copper ore types with seawater. The results show that the corrosion areas decrease when the temperature increases for both oxidized and sulfide minerals. It was confirmed that the concentration is a critical variable that influences the size of corrosion areas. In terms of the effect of the other ions that seawater contains, carbonate, chloride, and bromide affect the stability of the Cu-solid species. The proposed diagrams serve as a useful tool to predict the stable species that may be obtained when seawater is used. The use of seawater in mining is an essential issue because it is considered as a more sustainable alternative instead of use freshwater or desalinated seawater, especially in locations with complex water availability, as is northern Chile.

6

Study on seawater scrubbing for SO2 removal from ship's power plant exhaust gas

Ma Yiping, Xu Leping, Su Penghao, Feng Daolun, Yang Kailiang

Environment Protection Engineering

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2020

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Vol. 46, nr 1

31--47

EN

The mechanism of SO2 absorption in seawater is investigated, and the experiment was carried out accordingly. Emphasis is on applications of seawater scrubbing of ship’s power plant exhaust gas containing SO2. The formulated model is used to predict the influence of various parameters on both pH of tailwater and seawater desulfurization capability, e.g., the partial pressure of SO2, the partial pressure of CO2, tailwater temperature, pH and alkalinity of seawater. Experiment results indicated that the seawater desulfurization capacity increases with both increasing partial pressure of SO2, pH and alkalinity and decreasing partial pressure of CO2 and temperature. The study shows the desulfurization capacity of seawater with 3.5% salinity is approximately twice that of freshwater. Different scenarios in which the required absorbent supply rate for a given SO2 removal efficiency are studied. It is observed a 97% removal efficiency, corresponding to meeting the SOx limits in the SOx emission control areas (SECA) while operating on a heavy fuel oil containing sulfur 3.5 wt. %, requires a minimum water supply rate of 0.0407–0.0683 m3/kWh, depending mainly on the water composition in terms of alkalinity and salinity. Such data are important in assessing the operation cost of the water scrubbing system.

7

Influence of seawater salinity on corrosion of hull structural steel

Zagożdżon Paweł, Starosta Robert

Journal of KONES

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2019

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Vol. 26, No. 2

189--195

EN

Hulls of ships are often made of steel, which are produced under the supervision of classification societies. Usually, the hull steel of ordinary strength category A is used for the ship's shell (the yield strength is 235 MPa and the impact strength 27 J at 20ºC). Vessels sail in sea areas with various levels of salinity and thus with different corrosiveness. The average salinity of the seas is taken as 3.5% content of sodium chloride. This article presents the results of corrosion tests of S235 JRG1 steel in an aqueous solution in which the mass fraction of sodium chloride was: 0.7%, 1.4%, 2.2%, 2.8%, 3.5% and 4.2%. Corrosion tests were performed using the potentiodynamic method. As parameters characterizing the corrosion properties of the tested steel, the corrosion current density and corrosion potential were assumed. Statistically significant influence of seawater salinity on the corrosion properties of hull structural steel of ordinary strength of category A was found. The highest value of the corrosion current density was observed in the solution containing 3.5% NaCl mass fraction was observed. In seawater with a sodium chloride content in the range of 0.7 to 3.5%, an increase in the value of the corrosion current density was observed, along with the increasing share of NaCl. In seawater with higher salinity, the corrosion rate was reduced. The corrosion potential of S235JRG1 steel decreases with the NaCl content in the corrosive solution. The susceptibility of this material to corrosion in seawater increased.

8

Influence of seawater salinity on corrosion of austenitic steel

Starosta Robert

Journal of KONES

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2019

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Vol. 26, No. 3

219--225

EN

Due to the paramagnetic properties and the ability to passivation, for the production of hulls of some vessels (mainly warships), corrosion-resistant (stainless) steels with austenitic structure are used. This article describes the influence of seawater salinity on selected corrosion properties of high-alloy steel X5CrNi 18-10 (304). The average salinity of the seas is taken as 3.5% content of sodium chloride. Corrosion rate of the tested material was evaluated in an aqueous solution of sodium chloride was evaluated. The NaCl concentration in corrosive solutions was 0.7%, 1.4%, 2.1%, 2.8%, 3.5%, 4.2%. Corrosion tests were performed using the potentiodynamic method. The range of electrochemical potential changes was Ecorr ±150 mV. Corrosion rate was assessed on the basis of corrosion current density measurements. Corrosion potential values against the saturated calomel electrode were also determined. Based on the obtained measurement results and non-parametric significance tests carried out, a significant influence of seawater salinity on the value of corrosion current density and corrosion potential was found. The highest value of corrosion current density (jcorr), and thus the highest corrosion rate, was recorded for 3.5% NaCl solution. In the concentration range from 0.7 to 3.5% NaCl in solution, the corrosion rate of austenitic steel increases. A further increase in salinity of electrolyte results in the inhibition of corrosion rate of steel. There is almost a full negative, linear correlation between the proportion of sodium chloride in the corrosive solution and the value of corrosion potential. Along with the rise in the salinity of seawater, increase the electrochemical activity, and thus the corrosion susceptibility, thus the corrosion susceptibility, of the austenitic steel X5CrNi 18-10 was observed.

9

Monitoring of Physicochemical and Microbiological Quality of Taghazout Seawater (Southwest of Morocco): Impact of the New Tourist Resort "Taghazout Bay"

Lamine Imane, Alla Aicha Ait, Bourouache Mohamed, Moukrim Abdellatif

Journal of Ecological Engineering

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2019

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Vol. 20, nr 7

79--89

EN

The marine environment plays a major socio-economic role in the Agadir region (south-west Morocco). This area, which hosts important fishery resources, is currently not spared from the pollutants produced in the course of agricultural, domestic, industrial and tourist development. The aim of this study is to assess the impact of the Taghazout bay tourist resort on the bacteriological and physicochemical quality of the coastal waters of Taghazout. The seawater samples were collected between March 2016 and March 2018 at three sampling sites (S1, S2 and S3) in order to monitor the concentrations of fecal coliforms (FC), fecal streptococci (FS) and total germs (TG). The results of physicochemical parameters show seasonal fluctuations influenced by climatic factors. The spatio-temporal monitoring of the bacteriological parameters shows that the average total germ count is 127.05 CFU/100 ml, 39.61 CFU/100 ml for fecal coliforms and 15.21 CFU/100 ml for fecal streptococci. The values of FC80, FC95 and FS90 do not exceed the guide values of the Moroccan standards. This classifies the Taghazout beach in category A (good quality of bathing water). The monitoring analysis recorded by the Pearson correlation test between the environmental parameters and the level of fecal bacteria showed that there was a significant positive correlation between the FC concentrations and rainfall; the FS concentrations showed significant positive correlations with all the environmental parameters while the TG concentrations indicate no correlation with them. The fecal contamination parameters should be routinely monitored for improving the environmental conditions of coastal cities. This must be the case for the Taghazout coastline where a regular monitoring program must be established to evaluate the impact of the new tourist resort “Taghazout bay” on the environmental quality of this ecosystem.

10

Experimental investigation of seawater scrubbing of SO2 in turbulent contact absorbers and spray absorbers

Ma Yiping, Xu Leping, Zhou Junfeng, Yang Kailiang, Li Guoxiang

Environment Protection Engineering

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2019

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Vol. 45, nr 3

39--53

EN

The SOx emissions of the marine engine are regulated by international maritime conventions. In this paper, the effect of various parameters, including SO2 partial pressure, liquid to gas ratio (L/G), alkalinity and pH, was investigated by seawater scrubbing experiment in a turbulent contact absorber (TCA) and a spray absorber (SA) on a laboratory scale. The experimental data showed that the desulfurization efficiency of TCA was mainly dependent on the value of L/G and irrelevant to the changing way of L/G; the appropriate L/G of TCA was 2.3 dm3/m3 and pH of effluent water was 2.4–2.8 at the L/G of 1.1–2.8 dm3/m3. Comparatively, the desulfurization efficiency of increasing liquid flow rate was better than that of decreasing gas flow rate in the SA experiment. At the gas velocity of 1.58 m/s and L/G of 2.3 dm3/m3, the desulfurization efficiencies and drop pressures of TCA and SA were 75.9% and 42.4%, 690 and 260 Pa, respectively. The results indicate that TCA chosen as an absorber is likely to be a competitive desulfurization technique for controlling marine diesel emission.

11

Properties of the Baltic crude oil in the oil-in-water emulsion form : excitation-emission spectra

Baszanowska E., Otremba Z.

Journal of KONES

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2018

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Vol. 25, No. 1

7--14

EN

Due to the fact that marine environment contamination by oil substances are not uncommon, it is necessary to improve the ability of determine their origin. Therefore, research on the possibility of recognizing the type of oil using its individual characteristic manifested in the processes of fluorescence excitation has been undertaken. Oil pollutants present in seawater mainly coming from ship drives, tankers, pipelines or sea bottom seeps, moreover oil leaks from offshore extraction equipment also are possible. For this reason, the crude oil extracted from the Baltic Sea deposit in the Polish Maritime Areas has been chosen for tests. Fluorescence properties of water containing small amounts of oil (concentrations from 5.59 to 55.4 ppm) in the form of oil-in-water emulsion were tested. Individual samples were assigned matrices of fluorescent values for different wavelengths, while excited by monochromatic light also for different wavelengths. The obtained matrices were visualized as a contour maps and 3D charts. For considered concentrations of crude oil dispersed in water, the wavelength-independent fluorescence maximum was determined. Obtained result indicates that in the studied wavelength range, the total fluorescence intensity is proportional to the oil concentration only for the lowest oil concentrations. The analysis of the objective parameter of the difference between the shapes of spectra indicates the similarity of the spectral shape for the lowest oil concentrations. These results are the methodological suggestion, that for the purpose of identifying the type of oil dispersed in water, spectra should be determined for sequences of different dilutions, until the excitation-emission spectra shapes become independent from the oil concentration.

12

Properties of corrosive coated coatings multi-groove hardfacing on stainless steel

Woźniak P.

Journal of KONES

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2018

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Vol. 25, No. 3

511--516

EN

Using the pad welding technique it is possible to regenerate machine parts or improve surface properties such as abrasion, corrosion and aging resistance. To ensure optimum processing conditions and economic efforts should be made, while providing a high deposition efficiency for the small amount of metal in the pad weld substrate. The pad welding process for the test subject should be carried out by preheating to evaporate the moisture and reduce the porosity of the weld. This treatment is required depending on the carbon equivalent. The article presents the results of corrosion tests of multi-groove pads made with the MIG method on a steel substrate. The samples were made of C45E steel. The additional material was a wire made of stainless steel with the factory name CASTOMAG 4554S. The results of previously performed tests allowed determining the optimal process parameters at which we obtain the smallest share of the base material in the padding. Steel samples were prepared and preheated to 300ºC. The hardfacing process was carried out with constant parameters, i.e. current intensity, arc voltage, surfacing speed). Two protective gases were used to apply the additional material: CO2 and argon. The samples were subjected to corrosion tests in two environments (3.5% sodium chloride solution and 0.001 sulfuric acid solution). The assessment of corrosive properties was made on the basis of constant current measurements (potentiodynamic method). The influence of shielding gas on corrosion properties was demonstrated based on the tests.

13

Influence of alkaline solvents on the physical and mechanical properties of selected wood species

Zduniak D., Drożdżek M.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2018

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No. 103

77--83

EN

Three species of wood (larch, beech and red oak) were boiled in alkaline liquids. Wood species were divided into three groups for 30 samples each (the same average density and standard deviations). Samples were boiling in two types of liquids – seawater and black liquor. Time of boiling was always 20 hours. The density before and after treatment were measured also was investigated compressive strength parallel to grain after treatment. Native wood for each species was used as reference samples. Result show that wood samples density after treatment in seawater is a little smaller and after black liquid is bigger. Compressive strength parallel to fiber decrease after treatment in used alkaline liquids. The reason of this was probability smaller cracks inside wood and changes in chemical compositions of wood samples. Long time being in alkaline liquid with combination in drying process has negative influence of parameters of wood materials.

PL

Trzy gatunki drewna: modrzewia, buka oraz dębu czerwonego zostały poddane gotowaniu w cieczach o zasadowym charakterze. Gotowanie trwało 20 godzin i było prowadzone w wodzie morskiej oraz ługu czarnym. Grupy próbek do badań zostały dobrane zgodnie z gęstością (przy wilgotności W = 0%) tak, aby średnia gęstość i odchylenie standardowe w każdym zestawie były podobne. Na próbkach przed gotowaniem oraz po oznaczona została gęstość. Po procesie gotowania zbadano także wytrzymałość na ściskanie wzdłuż włókien. Próbki natywne zostały użyte, jako materiał odniesienia. Wszystkie poddano ściskaniu wzdłuż włókien na 4 tonowej maszynie Amslera. Na podstawie przeprowadzonych badań można wnioskować, że środowisko, w jakim przebywało drewno wpływa negatywnie na jego właściwości. Podniosła się gęstość, ale zmniejszyła się wytrzymałość na ściskanie wzdłuż włókien. Najmniejsze zmiany zaszły w przypadku drewna modrzewiowego. Prawdopodobnie jest to związane z żywicą która występuje naturalnie w tym gatunku.

14

Role of calcium and magnesium cations in the interactions between kaolinite and chalcopyrite in seawater

Uribe L., Gutierrez L., Laskowski J. S., Castro S.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

737--749

EN

A number of flotation plants around the world have increased the use of seawater due to limited sources of fresh water. The aim of this research work is to study the role that Mg2+ and Ca2+ ions play in the interactions between kaolinite and chalcopyrite in seawater. In order to achieve this objective, the effect of kaolinite on flotation of chalcopyrite is studied over the pH range from 8 to 11, when flotation is carried out in seawater and in a 0.01M NaCl solution. The influence of calcium, magnesium, sodium, and potassium ions on the extent of depression by kaolinite is evaluated. The micro-flotation results indicate that chalcopyrite is depressed by kaolinite in both 0.01 NaCl solution and seawater. In the 0.01 NaCl solution, the depressing effect of kaolinite decreases as the pH increases from 8 to 11. However, the results obtained using seawater show that the depressing effect of kaolinite is similar to what is observed in a 0.01 NaCl solution only at pH values below 9, but above this pH kaolinite significantly affects the recovery of chalcopyrite. The results from experiments with using solutions containing individual cations show that the depressing action of kaolinite in the presence of Mg2+ and Ca2+ is more obvious at pH values of 9 and 10, respectively, which correlates with the pH values at which the first hydroxy-complexes of these divalent cations start forming. This seems to indicate that depressing effect of kaolinite on chalcopyrite in seawater may be related to formation of hydrolyzed species of calcium and magnesium. These species can induce heterocoagulation between kaolinite and chalcopyrite. The trends observed in the micro-flotation experiments are in good agreement with the results of the induction time measurements and slime coating tests.

15

Essential factors for the changes in concrete during electrochemical extraction

Alsabry A.

International Journal of Applied Mechanics and Engineering

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2017

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Vol. 22, no. 2

443--450

EN

The objective of the article is to present one of the most significant factors affecting electrochemical removal of chloride ions from concrete. Based on the literature findings, tests were carried out on specimens containing chloride admixtures introduced to the cement grout, on elements subjected to chloride penetration from the solution in laboratory conditions and on fragments of constructions penetrated by chlorides as a result of a long-term exposure to seawater.

16

Zastosowanie procesu wymuszonej osmozy do odsalania i odnowy wody

Kabsch-Korbutowicz M.

Ochrona Środowiska

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2016

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Vol. 38, nr 1

9--14

PL

Proces wymuszonej osmozy (FO), nazywany też osmozą, inżynieryjną osmozą lub manipulowaną osmozą, jest membranowym procesem osmotycznym. Wykorzystuje on ciśnienie osmotyczne silnie stężonego roztworu odbierającego, jako siłę napędową, powodującą transport wody przez zwartą membranę polimerową ze strumienia zasilającego do odbierającego. W zależności od składu roztworu zasilającego i przeznaczenia uzyskanego produktu, etap ten może być jedynym wymaganym procesem. Jednakże w większości przypadków pełny układ, wykorzystujący proces wymuszonej osmozy, zawiera kolejny etap, polegający na regeneracji roztworu odbierającego i uzyskaniu czystej wody. Przewaga procesu wymuszonej osmozy nad klasycznymi technikami odsalania polega na mniejszej intensywności blokowania membran, mniejszym zużyciu energii, większej skuteczności retencji soli oraz większym strumieniu wody. Wymuszona osmoza jest coraz częściej stosowana jako proces separacyjny w oczyszczaniu ścieków, produkcji żywności i odsalaniu wód morskich lub słonawych.

EN

Forward osmosis (FO), also known as osmosis, engineered osmosis or manipulated osmosis, is an osmotically driven membrane process. FO utilizes osmotic pressure of a highly concentrated draw solution as a driving force to transfer water from a feed solution to the draw solution through a dense polymeric membrane. Depending on the concentration of solutes in the feed and the intended use of the product, this stage may be the only process required. In most cases however, a complete FO system utilizing the forward osmosis contains a subsequent step for the draw solute regeneration to finally produce a clean water. Potential advantages of FO over classical desalination processes include its low fouling intensity, low energy consumption, higher salt rejection and higher water flux. It attracts growing attention as separation process in wastewater treatment, food processing, and seawater/brackish water desalination.

17

Test of the suitability of chosen materials in terms of their use for removing oil spillage from the water environment

Guźlińska E., Kończewicz W., Otremba Z., Trojnar D.

Journal of KONES

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2016

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Vol. 23, No. 3

171--176

EN

The paper presents the study about impregnability of various loose materials dedicated as the fillers of oil absorbent socks and booms. Purpose of the survey was finding the material, which is characterized with the smallest hygroscopicity and the highest absorptivity towards typical fuels used in the marine techniques. The cause of take up the topic is the fact, that the contamination of sea areas with petroleum substances are unfortunately very often, are dangerous for natural environment and first of all are so hard to remove from the sea surface. The natural, mineral and synthetic sorbents were studied under laboratory conditions. Samples of the ten kinds of sorbent, each of 2 grams, were treated with the same amount of the diesel fuel, heavy fuel oil and the sea water also, each time in the same period-time (5 minutes). In order to determine the reliability of the results the authors carried out the test fivefold for the one of searched sorbents (recognized as the most hydrophobic-oleophilic substance). The results are presented in graphical form, based on which we are able to select sorbent that fulfils the greatest extent of required expectations. The results of performed tests show that the method that was described in the paper could be used to test the suitability of various materials for the production of devices for collecting the oil film from the surface of the water.

18

Petroleum in coastal seawater of Gdańsk Bay

Stelmaszewski A.

Oceanological and Hydrobiological Studies

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2015

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Vol. 44, No. 1

87--96

EN

The paper presents petroleum concentration in coastal waters of Gdańsk Bay, which was measured in 2006 – 2012. The oil concentration ranges from below the detection limit, i.e. 1 μg kg–1 to almost 120 μg kg–1. The concentration does not usually exceed 60 μg kg–1 and its average value is 11.7 μg kg–1. The presence of petroleum in coastal water is characterized by seasonality, with the lowest values in summer and the highest in winter. The conducted research showed that the coastal zone is not the source of petroleum contamination of the sea. The main reason for the presence of petroleum in the coastal water is the migration of polluted water within the bay. The inflow of pollutants from the mainland is yet another source of the contamination in the sea.

19

Fluorescence of natural seawater exposed to oil pollution

Otremba Z., Baszanowska E.

Journal of KONES

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2015

|

Vol. 22, No. 3

181--186

EN

The natural seawater contains both dissolved and suspended organic substances originating from natural sources and human activities – like the marine transport fleet among other. To specify the type and quantity of vitally valid as well as dangerous for properly functioning marine ecosystems substances complicated and sophisticated chemical instrumentation and methodologies must be used. Only a small number of seawater components it is possible easily to determine their concentrations – for example, the salt content is determined directly in the bulk of water through simultaneous measurement of electrolytic conductivity and temperature of water. It is worth to search similarly quick method for oil substances directly in the seawater. Taking into account seawater organic pollutants originating from natural sources inter alia crude oils, the presence of refinery petroleum substances due to their fluorescence in ultra-violet light can be determined based on fluorescence spectroscopy. The aim of this paper is to search fluorescence features of oil substances dissolved in natural seawater based on excitation-emission spectroscopy. In the paper fresh and oily contaminated seawater taken from the coastal area of the Baltic Sea were used. As an oil pollution ‘Petro-baltic’ oil were applied. The natural seawater, at first was laboratory exposed to low extremely amount of oil and then it was examined by fluorescence under UV light. The seawater from vicinity of Gdynia (Poland) were tested as fresh and after artificially contaminated by different amount of oil (from 0.5 to 500 ppm). Spectrofluorometer Hitachi F-7000 FL was applied to measure excitation-emission spectra (EEMs). Low amounts of oil (up to several ppm) cause increasing of main peak in excitation-emission spectra (EEMs). Addition of larger amounts of oil results in appearance new peaks, which originate from fluorescence of soluble fractions of oil artificially added to examined water. These specific features of oil describe the spectroscopic signatures of oil, which is the basis to development operational method of the source of oil pollution identification.

20

Comparison of fluorometric signatures of oil residues in both marine environment and in organic diluent

Otremba Z., Baszanowska E.

Journal of KONES

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2015

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Vol. 22, No. 3

175--179

EN

The significant part of petroleum substances is transferred to the marine environment after technical activities (inevitable exploitive spills, illegal discharges). However a certain part of petroleum in seawater coming from the natural sources. Therefore, to develop the safety of natural marine environment it is necessary to track not only the anthropogenic pollutants but also the natural sources of petroleum. To distinguish both source of oil the fluorescence properties of oil can be used as the tools to oil identification. The aim of the study is to describe the optical properties of crude oil after it contact with aquatic environment based on fluorescence spectroscopy. For the study, crude oil ‘Petrobaltic’ type potentially found in marine environment due to coming from natural source was applied. To dissolve oil, two different solvent – hexane and Baltic seawater form the Gdynia coast were used. To measure the excitation-emission spectra (EEMs) of oil spectrofluorometer Hitachi F-7000 FL was applied. In the paper, we discuss the changes of oil EEMs in two cases for oil dissolved in n-hexane and for oil dissolved in seawater for various oil concentration. Obtained EEMs for oil dissolved in seawater indicate that EEMs spectrum contain the main peak – describing by the wavelength – independent fluorescence maximum, which was detected for oil dissolved in n-hexane (typical for this kind of oil). However, the intensity of oil fluorescence decreases after oil contact with seawater. This approach could allow expanding the description of complex mixtures of oils as a possible tool proposed for identification the type and origin of oil found in marine environment.