Application of Solid Paraffin Inhibitor in Fracturing of Kuqa Ultra Deep High Pressure and High Wax Content Tight Condensate Gas Reservoir

The buried depth of gas reservoir B is more than 6700m, the thickness of reservoir is about 180m, the porosity of reservoir matrix is mainly 5.0% - 7.0%, with an average of 6.3%, and the permeability of reservoir matrix is mainly 0.01-0.1mD, The average production capacity of the three wells is 0.08mD, the formation pressure is 116-126MPa, the formation temperature is 124-131°C, the wax content of the condensate oil is high, and the average wax content is 16.9%. In the early stage, the natural productivity of the three wells was low, and the daily gas production was 120000-180000 cubic meters after stimulation. During the production process, the wellhead temperature was 20°C-25°C, the wax freezing temperature was 35°C, and the wellbore wax plugging was serious, The wellbore was blocked, the gas well was forced to shut down, and the reserves of 100 billion cubic meters were unable to be used, so it was necessary to explore new wax control technology. Through investigation, a new type of solid particle paraffin inhibitor is introduced, which can enter the artificial fracture with proppant during fracturing. When the condensate gas passes through the fracture, it washes the solid paraffin inhibitor which enters with proppant, and becomes the condensate gas containing paraffin control components.Therefore,it is not easy to form wax after entering the wellbore, which makes the problem of wellbore paraffin formation change from "passive control" to "active control". Referring to the relevant experimental standards, the conductivity, crushing test, solid paraffin inhibitor and fracturing fluid compatibility test were carried out. The existing test standards of wax freezing point are all for waxy oil under normal pressure, but not for condensate gas. A set of innovative experimental method is designed to successfully test the wax freezing point of condensate gas containing wax control components, and obtain the wax control effect under different ratios of wax control agent and proppant, so as to optimize the amount of wax control agent used in the experiment. The results show that the solid paraffin inhibitor has good dispersibility and suspension, and has little influence on the conductivity of sand filled fractures. The paraffin control effect on condensate oil and gas in this block is good. The wax freezing point can be reduced by about 12°C-18°C, and the optimal dosage is proppant 1%-2%. Field test was carried out in B gas reservoir. After fracturing, 5mm nozzle was used for production, tubing pressure was 83.6MPa, wellhead temperature was 28.8°C, daily oil production was 10.72 cubic meters, daily gas production was 217000 cubic meters, wellhead temperature was lower than wax freezing temperature in this area. At present, it has been in production for 6 months, and there is no wax deposit in wellbore. The successful test of solid paraffin inhibitor in the fracturing of Kuqa ultra deep high pressure and high wax content tight condensate gas reservoir provides a powerful technical reference for the wellbore flow guarantee of condensate gas reservoir.

BIOPHARMACEUTICAL ASPECTS OF CHOOSING THE BASIS OF PENCILS OF MEDICINAL WOUND-HEALING ACTION

Damage to the skin is quite common in everyday life of a person and represents a loss of the integrity of the protective barrier of the skin, which can create conditions for the development of a local inflammatory process, as well as for the penetration of pathogens of various diseases into the human body. In order to more quickly restore the damaged area of the skin, it is important to accelerate wound healing through the use of combined drugs, including antiseptics and biologically active substances of natural origin, stimulating the natural local regenerative process. One of such rational combinations is the combination of chlorhexidine bigluconate and Japanese Sophora fruit liquid extract in the composition of the wound-healing preparation. Medicinal sticks are presented as the most rational dosage form for a wound-healing drug of the specified composition. The application of this dosage form to the treated surface leads to the formation of a thin, firmly adhering film, which evenly releases the active substances and protects the wound from external influences. The indicated positive properties of medicinal pencils are achieved due to the selection of a rational component composition of excipients with a set of necessary characteristics, among which the most significant is the ability to provide optimal release of active substances. In this regard, the purpose of this study was to conduct comparative biopharmaceutical studies to optimize the component composition of medicinal pencils with wound healing action containing chlorhexidine bigluconate and liquid extract of sophora fruit. The objects of research were Japanese Sophora fruits harvested in 2020 in the Krasnodar Territory that meet the requirements of regulatory documents; substance-solution of chlorhexidine bigluconate 20%; auxiliary substances of lipophilic and hydrophilic nature: solid paraffin, beeswax, cocoa butter, anhydrous lanolin, polyethylene oxide-400, polyethylene oxide-1500. To assess the degree of release of active substances from experimental compositions, the method of diffusion into agar was used, based on the diffusion of active substances from the dosage form into an agar gel containing a solution of ferric chloride as an indicator. It was found that the most suitable combination of auxiliary components of the dosage form, providing the best release of active substances, is a combination including solid paraffin (20 parts), beeswax (20 parts), anhydrous lanolin (20 parts), polyethylene oxide-1500 (10 parts), polyethylene oxide-400 (20 parts).

Synthetic fatty acid from crude oil of Tamsagbulag petroleum deposit (Mongolia)

In this work, we studied to obtain synthetic fatty acids raw materials to produce surfactants and various detergents from paraffin. The solid paraffin extracted from the Tamsagbulag petroleum deposit was 46 mass%, distilled 350-450°C, by complexing with urea. Experimental study indicates paraffin's physicochemical characteristics from this petroleum are more suitable to use in the production of synthetic fatty acids. By solid paraffin oxidation, we obtained 33.01% of the synthetic fatty acids containing monocarboxylic acids.We suggest obtaining the synthetic fatty acid by oxidation process in normal condition from petroleum paraffin.

Macroscale modeling of solid-liquid phase change in metal foam/paraffin composite: Effects of paraffin density treatment, thermal dispersion and interstitial heat transfer

This work focuses on macroscale modeling of solid-liquid phase change in metal foam/paraffin composite (MFPC), addressing the treatment of paraffin density (under distinct paraffin filling conditions in metal foam), thermal dispersion effect and influence of thermal diffusion dominated interstitial heat transfer. To this end, a macroscale thermal non-equilibrium model for melting in MFPC with fluid convection is developed by employing the enthalpy-porosity technique and volume averaging approach. Meanwhile, visualized experiments on melting of MFPC sample are carried out to validate the modeling results. Comparing the numerical modeling and experimental visualization results, it is found that for MFPC with an initially saturated filling condition in metal foam using solid paraffin, the varied paraffin density is preferred to be employed for developing accurate phase change model. However, for MFPC that can be just filled with liquid paraffin after melting (i.e., non-saturated filling condition using solid paraffin), Boussinesq approximation is preferred to achieve satisfying phase change simulation. Thermal dispersion effect in MFPC is proved to be negligible, which should not be overvalued to avoid inducing physical distortions of heat transfer and fluid flow. Consideration of diffusion dominated interstitial heat transfer in the thermal non-equilibrium model is vital to accurately capture phase interface evolutions as well as to reasonably simulate the mushy zone of paraffin; and the model only incorporating the convection induced interstitial heat transfer will predict quite inaccurate phase change process. This study can provide useful guidance in macroscale modeling of phase change in MFPC.

Studies on the Efficiency of the Impact of Paraffin Inhibitors on Lowering the WAT Temperature and Reducing the Amount of Paraffin Deposit

This paper discusses the issues of the impact of pressure and temperature on the precipitation of paraffin deposits from reservoir fluids in the presence of previously prepared paraffin inhibitors. Using a properly modified PVT apparatus, the temperature of the beginning of paraffin precipitation (wax appearance temperature—WAT) has been determined, below which the solid paraffin phase was captured on a specialized filter in various temperatures. Based on the conducted experiments, a boundary has been established separating the paraffin area (the presence of paraffins as their solid phase) from an area without paraffin. Measurements of the amount of paraffin using the filter allowed the determination of the WPC (wax precipitation curve), due to which additional data is provided regarding the amount of precipitated paraffin deposit below the WAT. The developed methodology enables to conduct the measurements within a wide range of pressures using the sample saturated with reservoir gas, which can test the crude oil sample that corresponds to the actual production conditions. Most known research methods do not allow such preparation of a sample and conducting the measurements under pressurized conditions; therefore, the produced results are subject to errors. The paper describes also the studies of efficiency and differences in the action of various paraffin inhibitors. Based on the performed research, a comparison was made involving the action of agents under the pressureless conditions of dead oil and pressurized crude oil samples saturated with gas. The performed studies allowed the determination of equilibrium conditions (in a pressure–temperature system), under which deposition of the solid paraffin phase occurs during the use of three various inhibitors. Based on the performed experiments, an area with a paraffin hazard was determined, along with an area without paraffins. Due to the separation of the precipitated solid paraffin phase, an increase in the mass of the paraffin deposit associated with a temperature drop was determined (wax precipitation curve), as well as the impact of the applied inhibitors on its course.

LILIN AROMATIK MINYAK ATSIRI KULIT BATANG KAYU MANIS (Cinnamomum burmannii) SEBAGAI REPELEN LALAT RUMAH (Musca domestica)

This research was aimed to create aromatic candle, infused with cinnamon (Cinnamomum burmanii) bark essential oil, which is a potential repellant for house fly (Musca domestica). The distillation of akar wangi samples was carried out at the Spice and Aromatic Research Unit by vapor distillation method for 9-12 hours. The aromatic candles were based on a mixture of solid paraffin and stearin in a 2:8 proportion, respectively, enriched with fragrant root bark essential oils with 5 formulas, namely F1 (placebo), F2 (fixative), F3 (1% essential oil), F4 (2% essential oil), and F5 (3% essential oil). The repellency test was carried out by inserting 20 house flies in a of 50x50x50 cm container that contains a lighted aromatic candle according to the doses mentioned above, and shrimp scalps located 15 cm from the candle that functions as a bait. The calculated parameters were the hourly number of flies that were allured to the bait for 6 hours, which were related to the candle’s repellency and the house fly’s preference of candle. The repulsion ability result were 89.724%, 75.28%, 68.06%, 49.17%, 9.72% for F5, F4, F3, F2, and F1, respectively. The result also showed that the F4 sample was the most preferred sample.

UJI ANTIBAKTERI EKSTRAK DAUN SAMBUNG NYAWA (Gynura procumbens (Lour.) Merr.) DAN DAUN TAPAK LIMAN (Elephantopus scaber L.) TERHADAP Salmonella thypi

This research was aimed to create aromatic candle, infused with cinnamon (Cinnamomum burmanii) bark essential oil, which is a potential repellant for house fly (Musca domestica). The distillation of akar wangi samples was carried out at the Spice and Aromatic Research Unit by vapor distillation method for 9-12 hours. The aromatic candles were based on a mixture of solid paraffin and stearin in a 2:8 proportion, respectively, enriched with fragrant root bark essential oils with 5 formulas, namely F1 (placebo), F2 (fixative), F3 (1% essential oil), F4 (2% essential oil), and F5 (3% essential oil). The repellency test was carried out by inserting 20 house flies in a of 50x50x50 cm container that contains a lighted aromatic candle according to the doses mentioned above, and shrimp scalps located 15 cm from the candle that functions as a bait. The calculated parameters were the hourly number of flies that were allured to the bait for 6 hours, which were related to the candle’s repellency and the house fly’s preference of candle. The repulsion ability result were 89.724%, 75.28%, 68.06%, 49.17%, 9.72% for F5, F4, F3, F2, and F1, respectively. The result also showed that the F4 sample was the most preferred sample.

Water-stable and ion exchange-free inorganic perovskite quantum dots encapsulated in solid paraffin and their application in light emitting diodes

Perovskite quantum dots encapsulated in solid paraffin (P-PQDs) are water-stable and ion exchange-free, and show promising application in LEDs.