Bar Water Pressure Research Articles

PROSES PEMBUATAN TABUNG GAS 12 KG MENGGUNAKAN MATERIAL JIS-SG 255

A gas cylinder is a container in the shape of a tube and is used to store gas produced from oil refineries. The manufacturing process goes through various processes and the selection of strong materials to withstand the gas pressure in the cylinder. The main materials used in making the 12 kg gas cylinder are JIS SG 255 and SPHC. The 12 kg tube was designed with a tube height of 750 mm and a diameter of 280 mm. The SMAW welding process was carried out for the circumference and GMAW welding for the handguard and footring. To determine the area and volume of the weld on the 12 kg gas cylinder, area and volume calculations were carried out, so that it can be seen that the surface area of the 12 kg gas cylinder is 30.772 mm2, while the weld volume of the tube is known to be 115.395 cm3. Then, after welding the gas cylinder, proceed with annealing to restore the condition of the tube after welding with gradual heat temperatures, namely 200°C, 600°C and 200°C with a time of ± 14 minutes. Leak testing on tubes is carried out with two types of tests, namely hydrostatic tests and leak tests, hydrostatic tests on tubes use 31 bar water pressure with a quality of 50%, while for this leak test the tube is given air to find out whether the gas cylinder has a leak or not with a quality of 100 %.

Tunnel Swinemünde – Hydroschildeinsatz unter der Ostsee

AbstractThis paper discusses the concept and the practical experiences of excavating an under‐river crossing with a slurry shield (D = 13.45 m) to construct a single‐tube road tunnel. Unstable sand and gravel as well as harder chalk zones in the invert area combined with high groundwater pressure require the tunnel face to be actively supported at all times. Over long stretches the overburden to the river bed is only around 0.5 D, which means that a delicate balance has to be struck between achieving the minimum support pressure required to stabilise the tunnel face while at the same time preventing blow‐out. An innovative segment sealing system with integrated expanding insert combined with a push‐fit dowel system achieves a high degree of protection from moisture and voids. The evacuation and rescue concept for the single‐tube road tunnel is based on a refuge running under the carriageway. This evacuation channel is accessed via staircases in recesses at the side. Ground freezing is used to stabilise the sand during excavation of the recesses at around 4 bar water pressure.

Pipeline Condition Assessment by Instantaneous Frequency Response over Hydroinformatics Based Technique—An Experimental and Field Analysis

A common issue in water infrastructure is that it suffers from leakage. The hydroinformatics technique for recognizing the presence of leaks in the pipeline system by means of pressure transient analysis was briefly explored in this study. Various studies have been done of improvised leak detection methods, and Hilbert Huang Transform has the potential to overcome the concern. The HHT processing algorithm has been successfully proven through simulation and experimentally tested to evaluate the ability of pressure transient analysis to predict and locate the leakage in the pipeline system. However, HHT relies on the selection of the suitable IMF in the pre-processing phase which will determine the precision of the estimated leak location. This paper introduces a NIKAZ filter technique for automatic selector of Intrinsic Mode Function (IMF). A laboratory-scale experimental test platform was constructed with a 68-metre long Medium Polyethylene (MDPE) pipe with 63 mm in diameter used for this study and equipped with a circular orifice as an artificial leak in varying sizes with a system of 2 bar to 4 bar water pressure. The results showed that, although with a low ratio of signal-to-noise, the proposed method could be used as an automatic selector for Intrinsic Mode Function (IMF). Experimental tests showed the efficiency, and the work method was successful as an automatic selector of IMF. The proposed mathematical algorithm was then finally evaluated on field measurement tested on-site of a real pipeline system. The results recommended NIKAZ as an automatic selector of IMF to increase the degree of automation of HHT technique, subsequently enhancing the detection and identification of water pipeline leakage.

Hydrogen defects in feldspars: defect properties and implications for water solubility in feldspar

Hydrogen defects can strongly affect mechanical and chemical properties of feldspars. To get insight into the behavior of such defects, alkali feldspar and plagioclase of igneous origin were studied combining IR spectroscopy with heating experiments under well-controlled conditions. Near-infrared spectra show that OH groups are the predominant hydrous species in these feldspars but presence of minor amounts of molecular H2O cannot be excluded. Short-term annealing at 400–800 °C produces a small but significant irreversible change in the OH stretching vibration band which is attributed to relaxation of the feldspar structure. Polarized mid-infrared spectra of sanidine, adularia, and plagioclase recorded in situ at temperatures up to 600 °C show reversible shifts of maxima toward higher wavenumber and an overall decrease in integrated intensities. The pleochroic features of the OH vibration bands, i.e., the predominant orientation of OH dipoles along the crystallographic a axis in all feldspars and the additional band component perpendicular to the (010) plane in sanidine are still present in the high-temperature spectra. Different behavior during long-term annealing at high temperature was found for the alkali feldspars and the plagioclases. At 900–1000 °C, the Eifel sanidines rapidly lost about one quarter of the initial water content which is attributed to a weakly bound hydrogen species in the feldspar structure. The remaining hydrogen is very strongly bound and was still detectable in 0.7–0.9 mm thick sections after annealing for 108 days at 1000 °C in air dried by phosphorus pentoxide. In contrast, a 1-mm-thick section of plagioclase completely lost hydrogen during heating in air within 8 days at 1000 °C. After partial dehydration, the pleochroic behavior of the OH absorption bands of the feldspars was basically preserved except that the 3050 cm−1 band of the sanidine, oriented perpendicular to (010), becomes more pronounced than the 3400 cm−1 band, oriented parallel to the a direction. Annealing experiments at 1000 °C under controlled water pressures indicate equilibrium solubilities of several tens of ppm H2O in the plagioclases and more than 100 ppm H2O in the alkali feldspars already at 1 bar water pressure. The variation of the water content with H2O pressure and spectroscopic observations indicates that the water content in the feldspars is determined not only by the water pressure but also by already existing defects. Vacancies on alkali sites (VA1) may accommodate H2O molecules, possibly with subsequent hydrolysis of network bonds to minimize local stress. A likely explanation for the strongly bound hydrogen in the sanidine is a coupled substitution of H+ + Al3+ for Si4+ (AlOH defect) where the protons are located on interstitial sites. This incorporation model is supported by the complete recovery of the defects in H2O vapor after previous proton/alkali exchange in alkali chloride vapor at 1000 °C.

Preparation and characterization of porous cellulose acetate with copper (II) nitrate additives for separator applications

We succeeded in generating nanopores in a cellulose acetate (CA) matrix under water pressure using copper nitrate (Cu(NO2)2·4H2O) as the additive. The nanopores were produced when the polymer matrix was subjected to isostatic water pressure adding copper(II) nitrate into the CA membrane. The polymer chains were weakened by the plasticization effect of copper(II) nitrate present in the CA membrane. We confirmed that the pore properties were readily changed by water pressure as external physical forces with additive content. The water flux of the CA composite (CA/Cu(NO2)2·4H2O) membrane improved with increasing water pressure and additive content. For the CA membrane without the additive, the water flux was not measured from 1 to 8 bar water pressure. In contrast, the water flow of the polymer film with the additive varied from 95.3 to 205.75 L/m2h, depending on the water pressure and additive content.

Double pulse laser induced breakdown spectroscopy at 600 bar water pressure

The demand for raw materials is growing and deep-sea mining is becoming increasingly important. It is of great interest to be able to analyze materials directly in the deep sea for mining or research applications. Laser induced breakdown spectroscopy (LIBS) is a laser-based, non-contact method for analyzing material in terms of its elemental composition. This paper presents the design of a LIBS system to be operated in a water depth of up to 6000 meters. A compact double pulse laser with adaptable pulse interval was developed to address different water depths. The complete LIBS setup was tested in a pressure chamber and shows emission lines from zinc up to a water pressure of 600 bar. To the best of our knowledge, this was the first LIBS measurement at 600 bar water pressure.

Pipeline monitoring and leak detection using Loop integrated Mach Zehnder Interferometer optical fiber sensor

Abstract The Loop integrated Mach-Zehnder Interferometer (LMZI) optical fiber vibrational sensor was proposed to be implemented in pipeline monitoring and leak detection. The vibration sensing is based on power demodulation method using the torsion-sensitive LMZI sensor. In the 40 m steel pipeline field test, the LMZI sensor detected a significant leak-induced peak at ∼100 Hz during leak at 2 bar water pressure, whereas an additional ∼288 Hz peak was detected during leak at 3 bar water pressure. Both of the detected leak-induced frequencies were compared to the commercial accelerometer and showed good agreements with percentage errors of 0.4% and 2.64% at 2 bar and 3 bar respectively. The LMZI sensor is an alternative leak detection method which has great potential in replacing current conventional sensors in the future.

The effect of pressure and hydrocarbon expulsion on hydrocarbon generation during pyrolyzing of continental type-III kerogen source rocks

In order to define the roles of water and lithostatic pressure in petroleum formation of continental type-III kerogen source rocks, semi-closed hydrous pyrolysis experiments were conducted under with 50–1200 bar water pressure and 125–2000 bar lithostatic pressure at 480 °C. Our results will be of great benefit to the exploration of shale gas and deep petroleum in China. Increasing water pressure from 50 to 325 bar did not affect the yields of gaseous hydrocarbons, oil and bitumen, but increasing water pressure leads the more oil and less gaseous hydrocarbons from continental type-III kerogen in the 325–1200 bar water pressure range under semi-closed conditions. The decreasing yields of gaseous hydrocarbons, dryness of gaseous hydrocarbons and primary hydrogen together confirm that increasing water pressure promotes the primary reaction but decreases the cracking rate of oil. The decreasing values of S2, HI and H/C in the pyrolysed samples confirm that high water pressure can increase the efficiency of hydrocarbon generation from continental type-III kerogen, while the maturation of kerogen correspondingly increases as shown by increasing values of VR and Tmax. In the 125–625 bar lithostatic pressure range, oil cracking and primary reaction of type-III kerogen may have contributed to the decreasing effect of hydrocarbon expulsion. The increasing hydrogen and gaseous hydrocarbon yields also confirm that the cracking of oil is enhanced within this pressure range. The decreasing trends of oil and gaseous hydrocarbon yields indicate that hydrocarbon generation rate was reduced by the high lithostatic pressure in the 625–2000 bar pressure range. The increasing values of S2, HI and H/C, and decreasing values of VR and Tmax of pyrolysed samples confirm the retardation effect of highlithostatic pressure on the efficiency of hydrocarbon generation and maturation. In addition, the results also indicate that expelling hydrocarbons strongly promotes further hydrocarbon generation and retards the cracking of oil from continental type-III kerogen in source rocks.

The changes of hydrocarbon generation and potential in source rocks under semi-closed conditions with 50–840 bar water pressure

ABSTRACTIn order to investigate the effects of water pressure on hydrocarbon yields and potential in source rocks, carbonaceous mudstone from drilling in Liaohe Basin was pyrolyzed in simulation with constant water pressure and high-water-pressure experiments. Results demonstrate that the times of expelling hydrocarbon remarkably promote source rocks yielding liquid hydrocarbons. Increasing water pressure may increase the reaction of generating bitumen and oil, and enhance liquid hydrocarbons generation. Results of TOC, Rock-Eval, and elemental analysis in this study suggest that carbonaceous mudstone dominated by type-III kerogen remains a large number of hydrocarbon-generating potential, which may indicate that carbonaceous mudstone has a good potential to yield deep oil and natural gas. Besides, vitrinite reflectance may be the most suitable parameter to describe the maturity of source rocks.

Decontamination of Pig Carcasses Using Water Pressure and Lactic Acid

The objective of this work was to evaluate the effect of different water pressures and concentrations of lactic acid on microbial counts (mesophilic bacteria, enterobacteria and Salmonella) on pig carcasses without contamination and contaminated carcasses, before and after the last shower and before being cooled. The tests were carried out using 4, 3 and 2 bar water pressure, and 2, 1 and 0% lactic acid concentration. In general, both the pressure in the shower and lactic acid had a positive effect by reducing the microbial count. The interaction between the pressure and lactic acid caused the largest reduction in carcasses surface count for mesophiles. With regard to enterobacteria on contaminated carcasses, the most important variable was the lactic acid concentration and in uncontaminated carcasses, it was water pressure. The use of 8 bar pressure of the wash water without lactic acid caused a reduction in mesophilic bacteria and enterobacteria, for both the contaminated and uncontaminated carcasses, with results statistically equal to each other, and significantly lower than the initial counts. The water pressure at 8 bar reduced the percentage of carcasses with Salmonella in contaminated carcasses.

Siliceous extra-framework species in dealuminated Y zeolites generated by steaming

The dealumination of NH 4Y zeolite by steaming at 873 K and 1 bar water pressure is accompanied by a partial decomposition of the framework. X-ray amorphous aluminosilicate and silica gel are formed as extra-framework siliceous species in addition to the known polymeric aluminium ions. Source of the aluminosilicate and silica gel are Al-rich and Si-rich parts of the non-homogeneously crystallized FAU framework which are unstable during steaming. The Al-rich part consists of a Si/Al gradient as characterized by means of Molybdate experiments. The extra-framework siliceous species are identified by 29Si MAS NMR spectroscopic measurements as extra Si(4Al) and Si(0Al) signals which appear separated from the corresponding signal distribution of the zeolite framework. A certain portion of this silica gel superimposes, however, the Si(0Al) and Si(1Al) signal distribution of the zeolite framework. This “non-visible” part is quantified by the calculation of Si/Al ratio obtained by 29Si MAS NMR spectroscopy with respect to results obtained using the characteristic lattice parameter values.

Effect of temperature and time in the hydrothermal treatment of HY zeolite

Zeolite HY was steamed at 1 bar water pressure in steps of 100 K from 473 K to 1073 K in dependence of the time (0.5–20 h). Three routes of hydrothermal reactions can be outlined: At low temperature (473 K), a partly framework dissolution occurs accompanied by the formation of X-ray amorphous material. At intermediate temperatures (773–873 K), framework dealumination takes place with the occurrence of different non-framework species. Thereby, with increasing steaming time, saturation of the Si/Al ratio occurs on low levels (Si/Al ratios of about 4 and 5, respectively). At 973 K, a crossover from a low level saturation in Si/Al (6) towards higher values (11) is observed, which is accompanied by a partial amorphization of the zeolite with formation of aluminium oxide and silica gel and a significant decrease in crystal size as well. At high temperatures (1073 K), a fast thermal decomposition occurs. The IR spectra directly reveal an aluminosilicate phase as decomposition product of the framework. At 573 K, the zeolite framework remains unchanged.

Mechanism of 1-butene hydration over acidic zeolite and ion-exchange resin catalysts

Vapour-phase hydration of 1-butene at atmospheric pressure above 373 K shows similar features on both H-clinoptilolite and sulphonic acid ion-exchange resin: the initial reaction rate linearly increases with the partial pressure of 1 -butene and passes through a maximum as a function of water pressure. Kinetics was evaluated accordingly. A decrease in the 1-butene isomerization rate indicated that under hydration conditions more than 99.9% of the acidic sites are hydrated. For the hydration, however, hydroxonium ions are the active centres where an adsorbed water molecule reacts with gasphase 1-butene in the rate determining step. The equilibrated desorption of secondary butanol ends the reaction. The kinetic inhibition by butanol can be suppressed with water. Above ca. 0.2 bar water pressure inactive polyhydrated hydroxonium ions are formed.

Mechanism of 1-butene hydration over acidic zeolite and ion-exchange resin catalysts

Vapour-phase hydration of 1-butene at atmospheric pressure above 373 K shows similar features on both H-clinoptilolite and sulphonic acid ion-exchange resin: the initial reaction rate linearly increases with the partial pressure of 1 -butene and passes through a maximum as a function of water pressure. Kinetics was evaluated accordingly. A decrease in the 1-butene isomerization rate indicated that under hydration conditions more than 99.9% of the acidic sites are hydrated. For the hydration, however, hydroxonium ions are the active centres where an adsorbed water molecule reacts with gasphase 1-butene in the rate determining step. The equilibrated desorption of secondary butanol ends the reaction. The kinetic inhibition by butanol can be suppressed with water. Above ca. 0.2 bar water pressure inactive polyhydrated hydroxonium ions are formed.

Volume self-diffusion of oxygen in biotite, muscovite, and phlogopite micas

The kinetics of oxygen self-diffusion have been measured in natural samples of biotite, muscovite, and phlogopite micas under hydrothermal conditions using both bulk exchange and profiling analyses. All experiments were run at 1000 bars (100 MPa) water pressure except those designed to measure water pressure dependence, which ranged from 200 to 2000 bars. The Arrhenius relations obtained for layer-parallel diffusive transport in the three micas by bulk exchange experiments, fit to an infinite cylinder model, are Mineral biotite muscovite phlogopite Q (kcal mol) 34 ±2 39 ± 5 42 +- 3 D 0 (cm 2 s) 9.1 × 10 −6 7.7 × 10 −5 1.4 × 10 −4 T(°C) 500–800 512–700 600–900. The results of ion microprobe (SIMS) depth profiling perpendicular to the layers (parallel to c-axis) yield diffusion coefficients 3 to 4 orders of magnitude lower than for transport parallel to the layers. A single layer-parallel step profiling experiment yields a diffusion coefficient identical, within uncertainty, to those obtained from bulk exchange experiments. A slight dependence of diffusion rate on water pressure may obtain in phlogopite; however, the difference is approximately within the uncertainty of the measurement. Diffusion rates are similar, within about a half an order of magnitude, for a range of biotite composition from annite 4 to annite 63, as well as for muscovite. Comparison of oxygen diffusion rates in biotite from this study with Ar, K, and Rb diffusion from published data supports the idea that water is the oxygen-bearing species in hydrothermal diffusion experiments. The implication of these results for natural systems is that the micas, especially biotite, will continue to exchange oxygen isotopes via volume diffusion down to temperatures as low as 300 °C. The rapid diffusion kinetics may explain biotite oxygen isotope disequilibrium, which is commonly observed even in rocks where other mineral phases preserve equilibrium compositions.

Soil pollution by petroleum products, II. Adsorption-desorption of “kerosene” vapors on soils

Adsorption and desorption of vapor hydrocarbons from a synthetic “kerosene” source on different soils was studied. The “kerosene” used consisted of a mixture containing 20% aromatic components (m-xylene, n-butylbenzene, ps-cumene) and 80% aliphatic components (n-decane, n-dodecane). Three different types of soils were used: Mediterranean red sandy clays, arid brown loessial silty loam and Evesham clay. The most influential parameter in the adsorption-desorption processes was the moisture content, which was examined over a range from oven dry to −1 bar water pressure (70% field capacity). The highest adsorption values were on the arid brown loessial silty loam soil, having the following order of adsorption: n-decane > m-xylene > ps-cumene > n-butylbenzene > n-dodecane. From the “kerosene” components the fastest desorption rate was exhibited by m-xylene and the slowest by n-dodecane, in all the soil studied.

Oxygen and strontium diffusion kinetics in apatite and potential applications to thermal history determinations

The kinetics of oxygen and strontium diffusion in natural fluorapatite (Durango, Mexico) have been measured under hydrothermal conditions using an ion microprobe. Diffusion coefficients were obtained at temperatures from 550 to 1200°C for oxygen, and 650 to 1200°C for strontium. All experiments were run at 1000 bars (100 MPa) water pressure except those designed to measure the water pressure dependence, which were at 200 to 2000 bars. The Arrhenius relations obtained for diffusion parallel to the c axis at 1000 bars water pressure are: Element D0(cm2/sec) Q(kcal/mol) T(°C) Oxygen 9·10−5 49 ± 3 550–1200 Strontium 2·10−11 25 ± 4 650–1000 Strontium 1· 105 120 ± 22 1100–1200.The diffusion coefficient for oxygen transport parallel to the c axis is approximately three orders of magnitude greater than that perpendicular to the c axis over the temperature range of the experiments. No anisotropy was observed for strontium diffusion in apatite. An increase in water pressure from 200 to 2000 bars yields an increase in D of approximately a factor of three for oxygen diffusion parallel to the c axis at 800°C.The Arrhenius relation for strontium diffusion in the temperature range 1100 to 1200°C is in good agreement with the Watsonet al. (1985) data for dry 1 atm experiments at 1050 to 1250°C. Strontium diffusion coefficients obtained in the temperature range 650 to 1000°C yield significantly greater D values than predicted by extrapolation of the high-temperature Arrhenius relation. The new data show that closure temperatures calculated for strontium diffusion in apatite are significantly lower than the hightemperature studies would predict. Thus, apatite crystals would remain open to strontium diffusional exchange well below the solidus temperature of most igneous rocks. This could result in higher 87Sr86Sr values in the apatite than the whole-rock initial value. Measurable enrichment in 87Sr86Sr values in apatite could also be produced by a later thermal disturbance at moderate geologic temperatures and durations.

Oxygen diffusion in magnetite

The diffusion rate of oxygen in magnetite (Fe 3O 4) has been measured under hydrothermal conditions between 800° and 500°C at 1000 bars pressure, and yields the Arrhenius relation: D = 3.5 × 10 −6 exp(−/45,000RT) kcal/g-atom O. The diffusion rate was found to be the same, within the estimated uncertainty of a factor of 2, for measurements at 100, 1000, and 2000 bars (20–200 MPa) water pressure, and for oxygen fugacities buffered by magnetite-hematite and approximately Ni NiO. The activation energy and diffusion mechanism probably change to that given by Castle and Surman [10] at temperatures below 460°C. The oxygen diffusion rate in magnetite is between those of quartz and hornblende. Closure temperatures fall in the range 380°C for 0.1 mm radius grains cooling at 1°C/m.y. to 675°C for 1 mm radius and cooling at 1000°C/m.y. if the present data are used, but will be lower for the fine grain sizes and slow cooling rates if the Castle and Surman data are used.

Oxygen diffusion in amphiboles

The kinetics of oxygen isotope self-diffusion in natural samples of hornblende, tremolite, and richterite have been measured. Samples were run under hydrothermal conditions using 18O enriched water. Profiles of 18O ( 16O + 18O) vs depth into the crystal were obtained using an ion microprobe; the depths of sputtered holes were measured using an optical interferometer. At 1000 bars (100 MPa) water pressure, the activation energies ( Q) and pre-exponential factors ( D 0) for diffusion parallel to c are: D 0(cm 2/sec) Q (kcal/gm-atom) T (°C) Hornblende 1 +20 −1 × 10 −741 ± 6 650–800 Tremolite 2 +30 −2× 10 −8 39 ± 5 650–800 Richterite 3 +5 −2 × 10 −4 57 ± 2 650–800 The diffusion coefficient ( D) for hornblende at 800°C and 1000 bars water pressure measured parallel to the c crystallographic direction is at least ten times greater than that parallel to the a or b directions. An increase in water pressure from 200 to 2000 bars increases D by a factor of 2.7 for diffusion parallel to c at 800°C. The D value for hornblende at 800°C is about 0.01 that for quartz and 0.001 that for anorthite. As a result, closure temperatures for oxygen exchange in natural primary amphiboles are significantly higher than for quartz or feldspars. It is unlikely that amphiboles will exchange oxygen isotopes by diffusion under most crustal conditions.

D/H fractionation factors between serpentine and water at 100° to 500°C and 2000 bar water pressure, and the D/H ratios of natural serpentines

D/H fractionation factors between serpentine (clinochrysotile) and water were experimentally determined to be: 1000 In α ser-w = 2.75 × 10 7/ T 2 − 7.69 × 10 4/ T + 40.8 in the temperature range from 100 to 500°C. The present results do not support the semi-empirical fractionation factors employed by Wenner and Taylor [1] for the interpretation of δD values of natural serpentines. About 100 serpentines from the Japanese Islands have δD values from −110 to −40‰ SMOW, with antigorite being from −40 to −60‰. The results are in accord with the two conclusions by Wenner and Taylor [1,2], that is, the presence of a latitude −δD correlation and the more uniform and higher δD values of antigorite than chrysotile and lizardite. According to the present fractionation factors, almost none of the continental lizardite-chrysotile serpentines could have formed at a temperature below 500°C under equilibrium with fluids of δD values similar to the present-day local meteoric waters. The fluid responsible for oceanic serpentinization could be either a mixture of oceanic and magmatic water or oceanic water alone. However, full interpretation of the δD values of natural serpentines should wait until kinetic behaviors of hydrogen isotopes in serpentinization are better understood.