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Well I-25 of Field Jatibarang is an oil well that produces at 3746-3753 ft depth. The well perforation penetrates Pre Parigi unit of Cibulakan formation. The formation has porosity and permeability of 18 and 62 mD respectively. This specific unit is majorly consisted of limestone. I-25 has been indicated with CaCO3 scale and formation damage based on Stability Index method proposed by Stiff and Davis. The Stability index number obtained was +1.373 and skin factor was +0.85. Based on these numbers, it was then decided to perform matrix acidizing on I-25. Acid selection was based on the rock lithology. Chloride acid (HCl) was proposed due to its soluble products and high reactivity whenever the reaction involves limestone or dolomite. This paper's methodology begins with data acquisition, followed by calculation-based evaluation. The comparison of evaluation parameters ultimately tells if the stimulation succeeded or not. These parameters are as follows: flow rate, productivity index, inflow performance relationship, Skin factor, and flow efficiency,. Flow rate increased from 40 bfpd to 195 bfpd. Oil flow rate increased from 10 bopd to 35.3 bopd. Flow efficiency improved from 0.93 to 4.55 which indicates permeability improvement, primarily within the damage radius. Skin factor improved from +0.85 to -5.625, and transmissibility factor increased from 271 md-ft/cp to 276 md-ft/cp. Based on these numbers, it can be concluded that matrix acidizing performed on I-25 succeeded. [ABSTRACT FROM AUTHOR]

Acidizing of carbonate reservoir is a challenge to find optimum acidizing operation. Therefore, one of the most importance use acid to remove the damage of the near wellbore in the hole of the well. The main objective of this study to estimate technology, efficiency of productivity index (productivity decreases during production) and stimulate non- working but productive intervals in Mauddud Formation. Much of the world's oil and gas almost from Limestone and Dolomite Formations. Dolomites are similar to Limestone in Mauddud Formation with the exception that they generally action more slowly with hydrochloric acid (HCL). The problems and damage resulting from Formation can be very severe. Reduced permeability (K) due to the mobilization of the Formation material can shut off production itself. Four wells were used and the results obtained after the candidate wells selection for stimulation jobs will help the company to select the wells based on the model they choose. This paper shows the results of different acidizing methods with (selective acid treatment with coiled tubing packer, emulsified two phase retarded acid system, and combination of single phase retarded acid system with selective acid treatment and coiled tubing packer) for carbonate reservoir. Therefore acidizing can be used to improve productivity of production wells to reach two to three time of production oil well. Result show that the selective acid treatment with coiled tubing packer was most method to improve oil production in Badra Filed. [ABSTRACT FROM AUTHOR]

Application additives into the material for the production of wood pellets achieve an improvement in some properties such as pellets ash flow temperature and abrasion resistance. Additives their properties influence the course of combustion, and have an impact on the results of issuance. The experiment were selected additives corn starch and dolomite. Wood pellets were produced in the pelleting press and pelletizing with the additives. Selected samples were tested for the production of particulate matter (PM) during their direct burn. The paper analyzing a process of producing wood pellets and his effect on the final properties. [ABSTRACT FROM AUTHOR]

The study of wetting properties and surface free energy (SFE) of granodiorite, dolomite and recycled ceramic aggregate was presented in the paper. Every tested aggregate had different wetting properties. Based on the SEM study, the microstructure was shown. Wetting properties of various aggregates were determined by measuring the contact angle of their surface using water as measuring liquid. Many factors influence the contact angle, including physical and chemical homogeneity, roughness and surface contamination, type of measuring liquid, drop size of measuring liquid, humidity, ambient temperature, etc. Measurements were carried out 0 minutes after the time of application of the drops. The total SFE was determined using the Neumann method. Analyzing examination results it can be noticed that the values of contact angles depends on the absorbability of aggregate and smoothness of its surface. The results of contact angle measurements proved that all contact angles for ceramic aggregate were lower than contact angles for dolomite and granodiorite. That causes the total SFE for ceramic aggregate was higher than SFE for dolomite and granodiorite aggregate. The highest contact angle was noticed for granodiorite. The smallest contact angle with water was obtained by ceramic aggregate. This is due to physical characteristics of this aggregate. Ceramic aggregate is characteristic of the high absorbability. This indicates an increased wettability and increased adhesion properties. [ABSTRACT FROM AUTHOR]

The solar horizontal bubbling fluidized bed concept developed within the SOLPART research project can be used as a solar receiver-reactor. This application offers a considerable industrial potential, as illustrated in the paper further to different experiments and industrial contacts. The most demanding application is the calcination of limestone, either as pure calcite, or as 85% mix in cement raw meal. The decomposition temperature exceeds 850 °C (nearly the application limits of refractory steel alloys). Other calcinations (e.g. dolomite, gypsum, phosphate rock, meta-kaolin, clays, etc.) are less demanding since occurring at a lower calcination temperature and with an endothermic reaction heat that is significantly lower than the reaction heat of CaCO3, which is therefore considered as a relevant test case. [ABSTRACT FROM AUTHOR]

This paper reports a study on thermal decomposition of dolomite under CO2-air. Calcination was carried out non-isothermally by using thermogravimetry analysis-differential scanning calorimetry (TGA-DSC) with a heating rate of 10 °C/minute in an air atmosphere as well as 10 vol% CO2 and 90 vol% air atmosphere from 25 to 950 °C. In addition, a thermodynamic modeling was also carried out to simulate dolomite calcination in different level of CO2-air atmosphere by using FactSage® 7.0. The the main constituents of typical dolomite from Gresik, East Java include MgCO3 (magnesite), CaCO3 (calcite), Ca(OH)2, CaO, MgO, and less than 1% of metal impurities. Based on the kinetics analysis from TGA results, it is found that non-isothermal dolomite calcination in 10 vol% CO2 atmosphere is occurred in a two-stage reaction; the first stage is the decomposition of magnesite at 650-740 °C with activation energy of 161.23 kJ/mol, and the second stage is the decomposition of calcite at 775-820 °C with activation energy of 162.46 kJ/mol. The magnesite decomposition is found to follow nucleation reaction mechanism of Avrami Eroveyef (A3), while calcite decomposition follows second order chemical reaction equation. Thermodynamic modeling supports these kinetic analyses. The results of this research give insight to the kinetics of dolomite decomposition in CO2-air atmosphere. [ABSTRACT FROM AUTHOR]

Detailed petrographic and geochemical studies had been done to 89 samples from the Chuping Formation collected at Bukit Tengku Lembu area. The aim of this paper is to document the nature of dolomitization and its petrographical characteristics. Two types of dolomites have been recognized; stratified dolomites and non-stratified dolomites. Non-stratified dolomites can be further divided into complete-replacing dolomites, individual-scattered dolomites and selective-replacing dolomites. The geochemical data from X-ray Fluorescence analysis detected low concentrations of trace elements which includes Al, Fe, K, Mn, Na, P, Si, Sr and Ti, with a high Ca/Mg ratio ranging from 1.681 mol to as high as 106.942 mol. This big fluctuation in values indicates a variation of fluids that are involved in the diagenetic processes. Individual-scattered dolomites have perfect rhombus shape with no evidence of being affected by compaction and pressure indicating a shallow burial setting. Meanwhile presence of perfect saddle dolomites with replacive nature and no signs of being affected by compaction, also suggested late burial settings, in which compaction ceased. High Ca/Mg ratios may also suggest some dedolomitization effects. [ABSTRACT FROM AUTHOR]

Parque Estadual Turístico do Alto Ribeira (PETAR) is located in the South-western part of São Paulo State, in the Ribeira Valley. In this national state park a large number of caves are found, which are among the most visited of the country. These caves, located in a karstic zone, are characterized by the presence of carbonaceous rocks frequently fractured and collapsed. Although, carbonates (dolomites and calcitic rocks) usually have low U content, this element can be found in the structure of the surrounding rocks. This paper aims to determine 238U, 234U, 226Ra and 210Pb concentration in samples of rock, soil, river water and sediment, in Santana cave. The radionuclide 238U was determined by alpha spectrometry using a surface barrier detector. 226Ra and 210Pb were determined by measuring the gross alpha and beta activity on a gas flow proportional counter. [ABSTRACT FROM AUTHOR]

Kurrachine Dolomite (K.D) formation, which has Middle Triassic age, is considered as one of the most important formations in the northern Palmyrian sub-folding zone. It's existed in all places of the studied area, with thickness to be more than 500m, and depth to be approximately 2200m. Economic quantities of oil and gas were discovered in this formation in some tectonic units. Sedimentary burial, and geo-temperature histories for this formation were drown depending on real data from fourteen selected drilled wells in the study area, and then the sum of the time-temperature effects, were calculated, by using time-temperature Arrhenius index (ΣTTIArr), on the deferent types of kerogen, and the percent of the realized capacity on conversion into petroleum hydrocarbons were calculated. The results showed that K.D. formation may be only played partial role in forming hydrocarbons, and that only in some places in the studied area, while most of the petroleum hydrocarbons, reserved in this formation had been migrated from earlier formations. [ABSTRACT FROM AUTHOR]

This paper reviews about geopolymer based adsorbent focusing in the removal of heavy metal. The reviews include fundamental and types of material used in the formation of adsorbents. Geopolymer based adsorbent got attention recently due to its unique three-dimensional network structure, with fixed size pores and paths that allow certain heavy metal to pass through. Most materials that applied as adsorbent such as fly ash, metakaolin, kaolin and dolomite. A lot of sludge nowadays only dumped in the landfill which can be used as one of new materials as geopolymer based adsorbent. [ABSTRACT FROM AUTHOR]

Industry such as construction and materials had depended a lot on the available aggregate. The use of aggregate need to be designed so that it have a well sustainable system with good physical properties. This paper is using dolomite to produce an artificial aggregate. The dolomite based artificial aggregate is produced using geopolymer as a hardened process. The dolomite base artificial aggregate is tested with a different alkaline activator to find water absorption and density. The lowest water absorption of dolomite artificial aggregate is 14%. The specific gravity of the artificial aggregate tested are lower when the sodium silicate is decreasing. The lowest density of artificial aggregate obtain are with 2.03 g/cm3. [ABSTRACT FROM AUTHOR]

Zirconia toughened alumina (ZTA) is one of the composite ceramics that are widely use in load bearing and wear resistant applications. The composite is known for their good hardness and toughness, due to the presence of both Al2O3 and yttria stabilized zirconia (YSZ). The enhance toughness for ZTA are mostly originated from the presence of YSZ in the composite. The phase transformation from tetragonal to monoclinic that happen inside of YSZ during the presence of stress and increase its toughness. Thus, the amount of tetragonal and monoclinic phase inside of YSZ are critital to its toughness. In this research, the amount of dolomite was varied from 0 to 1.0 wt % while ratio of Al2O3 to YSZ were fixed to 4:1. The sample were prepared through the solid-state sintering method. XRD was done onto the sample to analyze the phases. XRD analysis shows that no presence of new compound in ZTA system. With addition 0.3 wt% of dolomite, Vickers hardness reached maximum of 1842.75HV. [ABSTRACT FROM AUTHOR]

Dolomite is one of carbonate minerals that contain magnesium. Magnesium is important element used in many aspects of life such as cofactor of many enzymes in human body, nutrient for plants, and raw material in automotive industry. Dolomite can be processed through low temperature process to obtain magnesium and calcium oxide that is needed in important applications such as base material for making drugs, raw material in the synthesize slow release fertilizer, materials for fire retardant, component for catalyst, etc. One of the important step of this low temperature process is dissolution of dolomite. Optimizing the dissolution process determines the % extraction of magnesium and calcium oxide from dolomite. The dissolution of dolomite from Gresik, East Java Provence Indonesia, in chloric acid solution has been conducted. Chloric acid concentration and pulp density are the variables that were observed. The dissolution of magnesium and calcium from Gresik dolomite was found to be very fast. The stable stage of dissolution can be reached for 5-10 seconds. The % extraction is mainly determined by the molar ratio of chloric acid / dolomite. At molar ratio of chloric acid / dolomite equal or above stoichiometric of dolomite dissolution, % extraction of magnesium is almost 100 %. [ABSTRACT FROM AUTHOR]

Comparisons are made between shock Hugoniot data and recent high-pressure static DAC (diamond anvil cell) data on dolomite mineral. Stark disparities are noted. DAC measurements reveal first order phase transformation within the pressure range of approximately 17-37 GPa. The preponderance of shock data failed to reveal phase transformation on the Hugoniot. Early time-resolved pressure reveal a possible transformation in the neighborhood of 20-25 GPa impeded by transformation kinetics. Static and dynamic data are contrasted and the underlying mechanisms assessed. [ABSTRACT FROM AUTHOR]