Gas Production System Research Articles

Innovative synthetic natural gas production from biomass and renewable hydrogen: Evaluation and optimization with sustainability perspective

Synthetic natural gas has a promising potential to contribute in sustainable supply of the natural gas and mitigating the intermittence issue of renewable energy sources. This study presents a novel system for synthetic natural gas production from biomass and renewable electrolytic hydrogen. A novel biomass and renewable electricity driven synthetic natural gas production system is presented. Hydrogen, an important input of the system, is supplied by biomass gasification and water electrolysis driven by renewable energy. Integrated system of photovoltaic panels and wind turbines supplies the required electricity of the system. An oxygen-steam mix is utilized as the gasification agent. An ion transport membrane is employed for oxygen production as an alternative to an expensive and complicated air separation unit. A comprehensive thermodynamic and economic analysis of the system is carried out. All equipment and ancillary costs are considered. Since solid carbon generation can lead to deactivation of the methanation reactor catalysts, the potential for solid carbon generation is considered for practicality. Multi-objective optimizations of different scenarios, are performed to determine the optimal economical and technical performance of the system. The optimization results indicate that the minimum cost for producing synthetic natural gas is 0.28 $/kWh. Furthermore, the heating value of synthetic natural gas is 41,500 kJ/kg, which closely approximates that of natural gas. Additionally, the price of the produced synthetic natural gas is lower than the price of natural gas in certain countries. In Sweden and the Netherlands, synthetic natural gas costs are notably 36% and 10% lower than conventional natural gas. However, in Germany, Austria, and Denmark, synthetic natural gas prices closely align with conventional natural gas rates, reflecting regional market variations.

326 Effect of Curing Extent on Ruminal in Vitro Gas Production Kinetics of Red Clover Hay and Silage Across Storage Phases

Abstract This study evaluated the effects of insufficient (WET) or ample (CUR) curing on red clover silage (29.4 and 45.3% DM, respectively) and hay (65.1 and 89.1% DM, respectively) in vitro fermentation measures. Measurements were taken at the start of storage (STRT), after 14 d (MicA), and once storage processes had stabilized for hay and silage (50 and 78 d, respectively; LATE). The red clover field was divided into 5 blocks and each block was divided into 2 plots and then assigned randomly to silage and hay (storage methods). Hay was packed into mini-bales (~500 fresh g; ~232 kg DM/m3) and silage into mini-silos (19.5 L; ~214 kg DM/m3). Samples at each storage stage were analyzed for in vitro gas production (48 h). Gas kinetics were recorded using the Ankom RF Gas Production System. Data were analyzed as a randomized complete block design (5 blocks) with a 2 (curing extents) x 2 (storage methods) x 3 (storage phases) factorial. Differences were declared at P ≤ 0.05. The data was analyzed using the GLIMMIX procedure of SAS 9.4. At STRT, the Asymptotic maximal gas production (M) and fermentation rate (k) were not different between CUR and WET hay (x̅ = 240.5 ± 7.33 mL/g incubated DM and x̅ = 13.2 ± 0.56% of gas production/h, respectively). However, at MicA, CUR hay had a greater M and k than WET hay (232.7 vs. 192.6 and 13.9 vs. 9.33, respectively). The same was observed at LATE (237.6 vs. 197.6 and 13 vs. 8.36, respectively). At STRT, the CUR and WET silage was not different for M and k (x̅ = 233.4 ± 7.33 mL/g incubated DM and x̅ = 14.06 ± 0.56% of gas production/h, respectively). A similar trend was observed at MicA (x̅ = 220 and 13.6, respectively) and LATE (x̅ = 219.7 and 14.7). In conclusion, ample curing of red clover hay preserves the fermentation kinetics relative to insufficient curing, especially after 14 d of storage. In the case of red clover silage, the fermentation kinetics was not affected by the curing extent across the storage period.

PSIV-5 High Desert Hemp Varieties Under Varied Nitrogen Fermentation Techniques Effects on Its Utilization as Livestock Feed Through in Vitro Fermentation

Abstract Nitrogen fertilizing of hemp varietals in high the high desert may assist in ensuring that production levels match the demand for growing hemp varietals. However, altering fertilizer levels may differently affect plant biomass and cannabinoid concentrations of plant tissues which changes the potential by-product utilizable for livestock feed. This study aimed to determine the influence of hemp fractions [flower (FL) vs stem and leaves (SL)] under three nitrogen fertilization regimens (0, 100, and 200 kg· ha-1) on in vitro rumen fermentation. Incubations runs consisted of triplicates of 500-mL bottles containing approximately 0.5 g of either ground SL or FL of hemp at the three nitrogen fertilization regimens. Rumen fluid was collected from two ruminally cannulated Angus steers, filtered through four layers of cheesecloth, and diluted to 4:1 with a standard buffer solution. A total incubation volume of 75 mL of the buffer: rumen fluid mix was added to each flask. Flasks were then placed in a rotating incubator (55 rpm) at 39°C, connected to an Ankom RF gas production system (Ankom Technology, Macedon, NY), and removed after 24, 48, and 96h. Total gas production (TGP), metabolizable energy (ME), ammonia nitrogen concentration (N-NH3), and total volatile fatty acids (VFA) were determined. Data were analyzed as a completely randomized design using lmer function in lme4 package in R with treatment and time as a fixed effect and replicates as a random effect. Statistical significance was established at P < 0.05 (Table 1). No differences were observed for N-NH3 (P > 0.05). Overall, SL samples had greater total VFA than FL, with T0SL having the greatest concentration among all treatments (P < 0.01). In congruence, acetate, isobutyrate, isovalerate, and the ratio between acetate and propionate concentrations were also greater for T0SL (P < 0.01). Concentrations of butyrate were greater for T200SL (P < 0.01), while T100SL had the greatest concentration of butyrate among all the treatments (P < 0.01). Overall, SL fractions of hemp seem to be more suitable as a ruminant feed source. The greater fat content of the FL compared with SL may detrimentally affect microbial populations and should further be explored. From our results, N supplementation significantly alters fermentation patterns during in vitro, which further warrants the evaluation of these feeds on in vivo experiments.

In vitro protein fractionation methods for ruminant feeds

Estimating protein fractions and their degradation rate are vital to ensure optimum protein supply and degradation in the digestive system of ruminants. This study investigated the possibility of using the ANKOM gas production system and preserved rumen fluid to estimate the protein fractions and in vitro degradability of protein-rich feeds. Three in vitro methods: (1) gas production method (2) Cornell Net Carbohydrate and Protein System (CNCPS), and (3) the unavailable nitrogen assay of Ross (uNRoss) were used to quantify protein fractions of four feeds (lupin meal, vetch grain, Desmanthus hay, and soybean meal). Rumen fluid mixed with 5% dimethyl sulfoxide and frozen at −20 °C was also compared against fresh rumen fluid in the gas production and uNRoss methods. All three methods ranked the feeds identically in the proportions of available (degradable or ‘a + b’) protein fractions as vetch grain, soybean meal, lupin meal, and Desmanthus hay in decreasing order. The use of fresh rumen fluid produced greater available protein fractions than preserved rumen fluid in all feeds. However, there was no difference between total gas production from lupin meal and vetch grain fermented for 16 h in either rumen fluid source. The in vitro degradable CP (IVDP) was higher for vetch grain (46 and 70%) at the 4th and 8th hours of incubation than other feeds, whereas soybean meal (85%) exceeded the other feeds after the 16th hour of incubation (P < 0.001). The greatest ammonia-N concentration was from soybean meal (1.27 mg/g) and lupin meal (0.87 mg/g) fermented for four hours using fresh rumen fluid. The proportion of fraction 'b' for soybean (82.1% CP) and lupin meals (39.4% CP) from the CNCPS method were not different (P = 0.001) from the fraction 'b' estimation of the gas production method for the same feeds (r = 0.99). Regardless of the methods, a greater water-soluble protein fraction was found from vetch grain (39.6–46.6% CP), and the proportion of fraction ‘c’ or unavailable protein in Desmanthus hay (39.1–41.5% CP) exceeded other substrates (P < 0.001). The strong positive correlation between fractions across different methods and identical ranking of feeds suggests the possibility of using ANKOM gas production apparatus for protein fractionation.

Technology Focus: Artificial Lift (October 2023)

Buying a vehicle can be a daunting experience. Sometimes you wish you could refer to a guide of what has worked out well for users of certain models over time and under various operating conditions. Paper SPE 213059 does this by correlating past testing of downhole centrifugal separators and adding a machine-learning twist. Once you’re about to make your selection at the car dealership, you may notice that the fine print states “mileage may vary” and wonder why that’s the case. Paper OTC 32398 explains how and why electrical submersible pumps (ESPs) are unable to perform as effectively when pumping viscous fluids by creating nondimensional models and validating them with field data. Paper SPE 214043 shows that frictional losses during plunger lifting can create a gap between actual and predicted performance. Even if you succeed in making a no-regrets purchasing decision, the day may arrive when financial, operational, or reliability considerations encourage changing vehicles and perhaps downsizing. Paper SPE 213089 describes an artificial lift selection tool for unconventional reservoirs driven by reduced-physics models that can help identify when the time is right for change. Paper SPE 213975 extols the value of gas lift downsizing by optimizing the selection and placement of Venturi, orifice, and dummy valves to spur production uplift. If you happen to have an emotional attachment to a vehicle, it can be difficult to let it go. But maybe you don’t have to; maybe you could repurpose that vehicle. Plenty of pump jacks in the history of the oil field have made use of truck transmissions instead of a standard gearbox. Paper SPE 214361 explains how ESPs could become electrical submersible generators to produce power in conjunction with injection or disposal operations. Then again, it may just be easier and less stressful to look up some bus schedules. Recommended additional reading at OnePetro: www.onepetro.org. SPE 213059 Application of Machine Learning To Evaluate the Performances of Various Downhole Centrifugal Separator Types in Oil and Gas Production Systems by Laura Camila Osorio Ojeda, University of Oklahoma, et al. OTC 32398 Relative Viscosity Model for Water-in-Oil Emulsion in Electrical Submersible Pumps: Comparing the ESP Head in a Real Scenario by Natan Augusto Vieira Bulgarelli, Unicamp, et al. SPE 214043 A Mathematical Modeling of the Plunger Lift Considering Effects of Fluid Friction and Plunger Travel Velocity by Saurabh Rajvanshi, Oil and Natural Gas Corporation, et al.

Enhancing gas production through advanced detailed design engineering: a global perspective on industry practices

Enhancing gas production through advanced detailed design engineering has become a pivotal approach in the global energy sector. This paper explores the integration of cutting-edge engineering methodologies to optimize gas production processes, reduce operational inefficiencies, and meet increasing energy demands. The application of detailed design engineering in gas production involves sophisticated modeling, simulation, and analysis of production systems, ensuring enhanced precision, safety, and scalability. By leveraging advanced computational tools, engineers can predict and mitigate potential production bottlenecks, optimize well designs, and implement efficient gas processing techniques. The global perspective on industry practices highlights regional variations in design standards, regulatory frameworks, and technological adoption. For example, North American gas fields utilize integrated digital twins and automation technologies to streamline production, while regions like the Middle East emphasize design optimization in offshore gas extraction. Additionally, the development of sustainable practices, such as carbon capture and storage (CCS) and energy-efficient processing units, is becoming a critical focus for gas producers striving to reduce environmental impact and align with international climate goals. This study also examines the role of collaborative frameworks between engineering teams and production operators in fostering innovation and knowledge transfer, further driving the refinement of detailed design approaches. The future of gas production will depend significantly on advancements in materials science, data analytics, and artificial intelligence, which are expected to revolutionize the design and operation of gas production systems. In conclusion, enhancing gas production through advanced detailed design engineering offers the potential to unlock new efficiencies, improve safety standards, and contribute to global energy security. However, the successful implementation of these practices requires continuous investment in research, technology, and cross-industry collaboration.

ANALYSIS OF VISCOSITY CORRELATIONS APPLICABILITY FOR OILS OF THE REPUBLIC OF BASHKORTOSTAN

Decisions quality of infrastructure development also depends on the reliability of multiphase flow modeling results in oil and gas production systems. Different specialized bundled software and Informational System RN-KIN are used for the modeling of multiphase systems to solve the assigned tasks for Republic Bashkortostan’s oil fields.&#x0D; The modeling practice assumes the handling of large amount of initial data: geometrical properties of pipe systems, terrain elevation, technological modes of pumping, conditions of heat exchange with the environment, transport properties of oil fluid. Information about network construction and terrain elevation can be obtained from the projects and the acts of implementation of these projects, the conditions of pumping are available from operation-dispatch information, but verification of viscosity properties of oil fluids causes difficulties and requires additional laboratory tests. At the same time on&#x0D; oil fields of Republic Bashkortostan a lot of experimental physicochemical properties data of oils belonging to different oil reservoirs has been accumulated, which requires systematization and generalization of available experimental data.&#x0D; The article describes the difficulties in modeling of viscosity of oil fluids taking into account the characteristics of physicochemical properties of oils of Republic Bashkortostan’s oil fields. The necessity of systematization of existing retrospective laboratory tests and selection of viscosity correlations is indicated. &#x0D; The authors of the article for the first time analyzed and selected correlations of viscosity of oil and water-oil emulsions for Republic Bashkortostan’s oil fields, which will allow to increase accuracy and efficiency of hydraulic calculations on which basis the decisions about development of infrastructure of fields are made.

Potential of the Red Macroalga Bonnemaisonia hamifera in Reducing Methane Emissions from Ruminants.

Researchers have been exploring seaweeds to reduce methane (CH4) emissions from livestock. This study aimed to investigate the potential of a red macroalga, B. hamifera, as an alternative to mitigate CH4 emissions. B. hamifera, harvested from the west coast of Sweden, was used in an in vitro experiment using a fully automated gas production system. The experiment was a randomized complete block design consisting of a 48 h incubation that included a control (grass silage) and B. hamifera inclusions at 2.5%, 5.0%, and 7.5% of grass silage OM mixed with buffered rumen fluid. Predicted in vivo CH4 production and total gas production were estimated by applying a set of models to the gas production data and in vitro fermentation characteristics were evaluated. The results demonstrated that the inclusion of B. hamifera reduced (p = 0.01) predicted in vivo CH4 and total gas productions, and total gas production linearly decreased (p = 0.03) with inclusion of B. hamifera. The molar proportion of propionate increased (p = 0.03) while isovalerate decreased (p = 0.04) with inclusion of B. hamifera. Chemical analyses revealed that B. hamifera had moderate concentrations of polyphenols. The iodine content was low, and there was no detectable bromoform, suggesting quality advantages over Asparagopsis taxiformis. Additionally, B. hamifera exhibited antioxidant activity similar to Resveratrol. The findings of this study indicated that B. hamifera harvested from temperate waters of Sweden possesses capacity to mitigate CH4 in vitro.

Evaluation of yeast-based additives, as an alternative to ionophores, on rumen fermentation of ruminant diets using an in vitro gas production system

IntroductionThe study aimed to assess yeast-based additives' effects, as monensin alternatives, on rumen fermentation parameters, greenhouse gas emissions, and ruminal kinetics of ruminant diets using an in vitro system. Three experiments were conducted, each individually evaluating escalating levels of three yeast-based additives.MethodsThree experiments were designed: Experiment 1 evaluated prebiotic blend 1—yeast culture [Saccharomyces cerevisiae (Scer)], beta-glucans, fructooligosaccharides, galactooligosaccharides, and mannanoligosaccharides; Experiment 2 investigated prebiotic blend 2—beta-glucan fractions and mannanoligosaccharides from Scer; Experiment 3 examined yeast cells—hydrolyzed, inactivated, and spray-dried yeast (Scer) cells. Uniform experimental design and procedures were employed across the three experiments. Each experiment had six treatments: monensin (Rumensin®, 25 mg/kg DM) as positive control, and yeast additive levels (0, 533, 1,067, 1,600, and 2,133 mg/kg on DM basis) added to ruminant diets (60% corn silage and 40% concentrate). An in vitro gas production (GP) system with 50 AnkomRF bottles assessed total GP (at 24 and 48 hours), kinetics, fermentation profiles, methane (CH4), and carbon dioxide (CO2) concentrations. Comparison with monensin utilized Dunnett’s test (5%). Yeast additive levels were analyzed for linear and quadratic responses.ResultsIn Experiment 1, the 1,600 mg/kg yeast additive had lower concentrations of propionate, isobutyrate, valerate, and branched-chain volatile fatty acids (BCVFAs), and a higher acetate concentration and acetate-to-propionate ratio than monensin. In Experiment 2, the 1,600 mg/kg yeast additive led to lower total VFA and isovalerate concentrations than monensin. Additionally, compared to the 1,067 mg/kg yeast additive, monensin showed lower isovalerate concentration and higher NH3-N concentration. In Experiment 3, the 533 mg/kg yeast additive resulted in lower valerate and BCVFA concentrations, and higher CH4 and CO2 concentrations than monensin. Monensin had lower total VFA, butyrate, and acetate-to-propionate ratio, and higher propionate concentration compared to the 2,133 mg/kg yeast additive.DiscussionCollectively, these findings suggest yeast-based additives could be monensin alternatives, enhancing animal nutrient utilization efficiency and contributing to improved livestock sustainability.

Implementation of Core Competency and Life Cycle Assesment (LCA) In the CID Program Petani Maju 4.0 of PT Pertamina Hulu Mahakam

This article aims to describe the importance of integrating the concept of Life Cycle Assessment (LCA) in the Community Involvement Development (CID) program. Based on Permen LHK 1/2021 concerning Proper, LCA must be the basis for every company to develop programs based on community empowerment. This article provides an overview of the case studies in PT Pertamina Hulu Mahakam's CSR 4.0 Maju Farmer program which has integrated linkages with LCA. The LCA study of PT Pertamina Hulu Mahakam covers the cradle-to-grave function unit. Cradle-to-grave function The product systems studied for life cycle assessment have covered 100% of products, namely petroleum, natural gas and condensate production systems. The oil and gas production process certainly has an impact on the activities of people's lives which must be explained with a CSR-based community empowerment approach. The results of the integration of LCA and the CSR program of Farmers Maju 4.0 were able to utilize the company's 33 tons of organic waste into compost and alternative feed for livestock. As well as environmental improvements, it can contribute to reducing greenhouse gas emissions by 259.2 kilograms of methane gas per year.

Prediction of dynamic liquid level in water-producing shale gas wells based on liquid film model

The accumulation of liquid in shale gas wells will lead to an increase in bottom-hole pressure, and a decrease in production, even the shutdown of gas wells. Accurately predicting the variation of liquid height in shale gas wellbore and the corresponding production is helpful to determine the liquid accumulation status and the development of reasonable drainage construction plans. It can provide theoretical support for the efficient and stable production of shale gas wells. A predictive analysis model of shale gas wellbore liquid accumulation was established based on a liquid film carrying model, which considers the coupling of flow in the reservoir and wellbore in shale gas production system. This model can accurately predict the liquid accumulation height, production rate, and the bottomhole pressure changes in liquid-accumulating gas wells. A comparative analysis was conducted on the effect of wellbore structure on liquid accumulation characteristics in the typical upward-type and downward-type horizontal wells in the W block. In upward-type horizontal wells, the liquid height increases slowly before the liquid accumulation fills the horizontal section, and the liquid height increases rapidly after the liquid accumulation fills the horizontal section. Compared to upward-type horizontal wells, the liquid height rises more quickly and the gas production rate is more sensitive to liquid accumulation in downward-type horizontal wells.

Modulating Natural Methane Release from Rumen Fermentation through the Use of Ficus glomerata Leaf Tannins in Murrah Buffalo (Bubalus bubalis)

Enteric fermentation is one of the largest contributors of methane release to the environment from the livestock sector. Plant bioactive compounds can modulate rumen fermentation for reduced methanogenesis and fatty acid biohydrogenation. The present study investigates the effects of tannin extract from Ficus glomerata (FG) leaves on the rumen fermentation, methanogenesis, feed digestibility and fatty acid biohydrogenation of a total mixed ration with the aim of developing a feed supplement for enhanced livestock production and product quality with lower methane emission. The tannin extract (70% aqueous acetone extract) of FG leaves in the total mixed ration (oat hay/concentrate mixture; 1:1) was studied at four graded dose regimens (0.0 (control), 0.25 mL (FG-0.25), 0.50 mL (FG-0.50) and 1.0 mL (FG-1.0) per 60 mL of buffered rumen fluid) in three replicates for each treatment in a radio-frequency-based automatic gas production system (ANKOM-RF) at 39 °C for 24 h following the standard in vitro gas production protocol. The total gas production (mL or mL/g incubated dry matter (DM)) was gradually reduced (p &lt; 0.01) at dose levels of FG-0.50 and FG-1.0; however, it remained intermediary and comparable (p &gt; 0.05) for FG-0.25 with the control and FG-0.50. Compared to the control, the methane concentration (%) in the head space gas, as well as the total methane production (mL or mL/g DM incubated, or mL/g DM digested), were found to be gradually reduced (p &lt; 0.01) with increasing doses (0.25–1.0 mL) of FG extract. The reduced (p &lt; 0.05) feed degradability at higher levels (0.50–1.0 mL) of FG extract supplementation and the comparative (p &gt; 0.05) effects with the control at a lower level of supplementation (FG-0.25) are suggestive of the dose-responsive detrimental effects of tannins on fibrolytic microbes in the rumen. However, the ammonia concentration decreased (p &lt; 0.05) in all of the incubations compared to the control. Among the volatile fatty acids, acetate remained comparable (p &gt; 0.05) with enhanced (p &lt; 0.05) propionate at a lower dose (FG-0.25); however, a dose-dependent reduction was evident at higher dose levels (FG-0.50 and FG-1.0). The production of stearic acid (C18:0), which is a product of the rumen biohydrogenation process, was reduced (p &lt; 0.05), irrespective of the concentration of the FG extract. Compared to the control, the concentration of t-vaccenic acid (C18:1), which is a precursor of conjugated linoleic acid (CLA) in animal products, was increased in all the FG-extract-supplemented groups. It may be concluded that Ficus glomerata leaf tannins can modulate rumen fermentation for reduced methanogenesis and fatty acid biohydrogenation in a total mixed ration. As a higher level of inclusion negatively affects feed digestibility, a lower dose (0.25 mL FG extract per 60 mL fermentation fluid or 4.17 mL FG extract per L of fermentation fluid) is suggested to achieve desirable effects on methane abatement (30%) and an improvement in fatty acid profiles in animal products.

RATIONALE FOR CHOOSING CORRELATIONS FOR GAS HYDRATE FORMATION TEMPERATURE COMPUTATION FOR GASES OF VARIOUS COMPOSITIONS

Gas hydrates are the object of continuous research in the oil and gas industry. Gas hydrates can form in gas production systems: in the bottomhole zone, in the wellbores, in plumes and infield reservoirs, in gas treatment systems, as well as in main gas transport systems, causing serious problems associated with the disruption of these processes. However, recently, the gas industry has found new uses for hydrates (for example, energy recovery, separation, storage, and transportation of gas) prompting scientists to conduct new and more detailed studies of the hydrate formation process.&#x0D; Understanding the conditions and mechanisms of hydrate formation makes an engineer able to control this process. Therefore, in practice, simplified models are often required to predict hydrate formation. This paper presents various correlations that are widely used in the oil and gas industry to determine the temperature of hydrate formation. The accuracy of the presented models is compared. The influence of the features of the gas composition on the conditions for the hydrates formation is studied.&#x0D; It is shown that for the considered gases, the most accurate results can be obtained using the G.V. Ponomarev correlation. When the relative density of gases is greater than 0.6, it is possible to use the Towler and Bahadori correlations. Correlations proposed by Hammerschmidt, Mottie and Berge show the worst results.&#x0D; Since the temperature of hydrate formation in the considered correlations does not depend on the gas composition, but only on the relative density, the influence of the content of non-hydrocarbon components on the temperature of hydrate formation was studied in this work. It was found that the content of hydrogen sulfide has the greatest influence. Moreover, at high contents of hydrogen sulfide in the gas composition, the temperature of hydrate formation shifts towards higher values. The content of nitrogen and carbon dioxide to a lesser extent affect the value of the temperature of hydrate formation.

Opracowanie skutecznych zespołów uszczelniających dla urządzeń naftowych w systemie wydobywczym ropy i gazu

The paper presents the results of many years of experience in studying the efficiency of sealing units in the conditions of their operation in the oil and gas production system, as well as the influence of technological parameters that ensure normal operation and protect them from failure due to leakage through the working surface of the seals in the friction zone. In addition, according to the results of practical studies, it has been established that, in order to improve the elastic properties, for example, of cup springs of a direct-flow valve, we calculated heat treatment of the operational values of spring compression for various material thicknesses. The work of the elastic elements of the packer was improved mainly by the design, and the optimal parameters for the development of the elastic element of the packer were determined. The study of the stress-strain state of the sealing element of packers during setting and improving its performance is of both practical and scientific interest. One of the factors that significantly affect operation of pumps is the fluid leakage in valve assemblies in order to identify the effect of the above parameters on tightness based on a preliminary theoretical analysis. Comparison of data during the study showed that the flow rate of work with low viscosities is greater than with high viscosities. The technological processes of hardening the parts of the shut-off assembly of X-mas tree valves, to increase their reliability, are considered. The dependence of the compression force of the spring and its deformation because of geometric parameters of the disk springs has been determined; it has been found that the residual deformation of the disk spring after collapse has a negative effect on tightness. Calculations show that the amount of leakage of the elastic elements in the sealing assembly should not exceed ≤0.309, since the seal at the value of elastic energy deformation provides a self-compacting mode. Thus, the degree of uneven pressing of the seat to the surface of the gate and its regulation to prevent leakage is practically determined.

Modulation of Murrah Buffalo (Bubalus bubalis) Rumen Functions for In Vitro Fatty Acid Bio-Hydrogenation, Methane Production and Fermentation Pattern of Total Mixed Ration Supplemented with Allium sativum (Garlic) Essential Oils

The potential for plant-origin essential oils to modulate rumen functions for reducing bio-hydrogenation of fatty acids and methane production has been a significant area of research in recent times. This study investigated the effects supplementation of garlic (Allium sativum) essential oils have on in vitro bio-hydrogenation of fatty acids, methanogenesis and fermentation characteristics of total mixed ration in buffalo with the aim of enhancing conjugated linoleic acid (CLA) content in animal products as well as reducing environmental pollution. Allium sativum (AS) essential oils were examined at four levels [0 (Control), 33.33 µL (AS-1), 83.33 µL (AS-2) and 166.66 µL (AS-3) per litre of buffered rumen fluid] in a radio-frequency based automatic gas production system (ANKOM-RF). Two bottles per treatment per run over two incubation runs were undertaken to gain representative results. Oats hay and concentrate mixture (1:1) was used as a substrate (500 ± 5 mg) and incubated with 60 mL of buffered rumen fluid in 250 mL ANKOM bottles fitted with automatic an gas recording system at 39 °C for 24 h, following standard in vitro gas production protocols. The results demonstrated a reduction (p &lt; 0.01) in lipid bio-hydrogenation, measured by lowered saturated fatty acids and enhanced unsaturated fatty acids on the supplementation of AS essential oils, irrespective of the dose levels. Moreover, the increased (p &lt; 0.01) production of trans vaccenic (trans C18:1) acid (TVA) following graded dose supplementations of the AS essential oils increased the production of conjugated linoleic acids (CLA) in animal products. Although, reduced methane production (p &lt; 0.01) was evidenced, the decrease in total gas production and feed digestibility (TDDM) demonstrated the strong antimicrobial properties of AS at all dose levels. The study reveals that the Allium sativam (Garlic) essential oils have the potential to be an agent for the reduction of the rumen biohydrogenation of fatty acids and methanogenesis. However, in vivo examination is necessary to validate the findings and confirm its suitability for use as an additive to enhance nutraceutical and organoleptic properties in animal products.

Screening macroalgae for mitigation of enteric methane in vitro

This study investigated the effects of 67 species of macroalgae on methanogenesis and rumen fermentation in vitro. Specimens were analyzed for their effect on ruminal fermentation and microbial community profiles. Incubations were carried out in an automated gas production system for 24-h and macroalgae were tested at 2% (feed dry matter basis) inclusion rate. Methane yield was decreased 99% by Asparagopsis taxiformis (AT) when compared with the control. Colpomenia peregrina also decreased methane yield 14% compared with control; no other species influenced methane yield. Total gas production was decreased 14 and 10% by AT and Sargassum horneri compared with control, respectively. Total volatile fatty acid (VFA) concentration was decreased between 5 and 8% by 3 macroalgae, whereas AT reduced it by 10%. Molar proportion of acetate was decreased 9% by AT, along with an increase in propionate by 14%. Asparagopsis taxiformis also increased butyrate and valerate molar proportions by 7 and 24%, respectively, whereas 3 macroalgae species decreased molar proportion of butyrate 3 to 5%. Vertebrata lanosa increased ammonia concentration, whereas 3 other species decreased it. Inclusion of AT decreased relative abundance of Prevotella, Bacteroidales, Firmicutes and Methanobacteriaceae, whereas Clostridium, Anaerovibrio and Methanobrevibacter were increased. Specific gene activities for Methanosphaera stadtmane and Methanobrevibacter ruminantium were decreased by AT inclusion. In this in vitro study, Asparagopsis taxiformis was most effective in decreasing methane concentration and yield, but also decreased total gas production and VFA concentration which indicates overall inhibition of ruminal fermentation. No other macroalgae were identified as potential mitigants of enteric methane.

Isoacids supplementation improves growth performance and feed fiber digestibility associated with ruminal bacterial community in yaks.

This study was conducted to assess the effect of mixed isoacid (MI) supplementation on fermentation characteristics, nutrient apparent digestibility, growth performance, and rumen bacterial community in yaks. A 72-h in vitro fermentation experiment was performed on an ANKOM RF gas production system. MI was added to five treatments at doses of 0, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% on the dry matter (DM) basis of substrates using a total of 26 bottles (4 bottles per treatment and 2 bottles as the blank). Cumulative gas production was measured at 4, 8, 16, 24, 36, 48, and 72 h. Fermentation characteristics including pH, the concentration of volatile fatty acids (VFAs), ammonia nitrogen (NH3-N), microbial proteins (MCP), and the disappearance rate of dry matter (DMD), neutral detergent fiber (NDFD), and acid detergent fiber (ADFD) were measured after a 72-h in vitro fermentation to determine an optimal MI dose. Fourteen Maiwa male yaks (180-220 kg, 3-4 years old of age) were randomly assigned to the control group (without MI, n = 7) and the supplemented MI group (n = 7, supplemented with 0.3% MI on DM basis) for the 85-d animal experiment. Growth performance, nutrient apparent digestibility, rumen fermentation parameters, and rumen bacterial diversity were measured. Supplementation with 0.3% MI achieved the greatest propionate and butyrate content, NDFD and ADFD compared with other groups (P < 0.05). Therefore, 0.3% was used for the animal experiment. Supplementation with 0.3% MI significantly increased the apparent digestibility of NDF and ADF (P < 0.05), and the average daily weight gain of yaks (P < 0.05) without affecting the ruminal concentration of NH3-N, MCP, and VFAs. 0.3% MI induced rumen bacteria to form significantly different communities when compared to the control group (P < 0.05). g__norank_f__Bacteroidales_BS11_gut_group, g__norank_f__Muribaculaceae, g__Veillonellaceae_UCG-001, g__Ruminococcus_gauvreauii_group, g__norank_f__norank_o__RF39 and g__Flexilinea were identified as the biomarker taxa in responding to supplementation with 0.3% MI. Meanwhile, the abundance of g__Flexilinea and g__norank_f__norank_o__RF39 were significantly positively correlated with the NDF digestibility (P < 0.05). In conclusion, supplementation with 0.3% MI improved the in vitro rumen fermentation characteristics, feed fiber digestibility, and growth performance in yaks, which was associated with changes of the abundance of g__Flexilinea and g__norank_f__norank_o__RF39.

Combining unscented Kalman filter and wavelet neural network for anti-slug

The stability of the subsea oil and gas production system is heavily influenced by slug flow. One successful method of managing slug flow is to use top valve control based on subsea pipeline pressure. However, the complexity of production makes it difficult to measure the pressure of subsea pipelines, and measured values are not always accessible in real-time. The research introduces a technique for integrating Unscented Kalman Filter (UKF) and Wavelet Neural Network (WNN) to estimate the state of subsea pipeline pressure using historical data and a state model. The proposed method treats multiphase flow transport as a nonlinear model, with a dynamic WNN serving as the state observer. To achieve real-time state estimation, the WNN is included into the UKF algorithm to create a WNN-based UKF state equation. Integrate WNN and UKF in a novel way to predict system state accurately. The simulated results show that the approach can efficiently predict the inlet pressure and manage the slug flow in real-time using the riser's top pressure, outlet flow and valve opening. This method of estimate can significantly increase the control effect.

Intelligent safe operation and maintenance of oil and gas production systems: Connotations and key technologies

Oil and gas production systems have the characteristics of high operation and maintenance risk and great accident influence. With the deep integration of informationization and industrialization, the development direction and necessary choice of the oil and gas industry is to develop the oil and gas production system into the interconnected, multi-domain interactive cyber-physical intelligent system. In order to avoid or reduce the complex, diverse and potentially unknown safety risks in the process of oil and gas production, improve the safety and reliability of oil and gas production system and increase the production efficiency, this paper analyzes the safety problems occurring in the intelligentization process of oil and gas production system and constructs a system from the perspective of operation and maintenance based on key elements of intelligent safe operation and maintenance technology, combined with the typical production scenarios in the oil and gas production industry. And the following research results are obtained. First, the connotation of intelligent safe operation and maintenance technology is clarified, the key elements and existing problems and challenges of intelligent safe operation and maintenance technology are analyzed, and the “1-2-3-4-5-6” intelligent safe operation and maintenance technology system of oil and gas production system is constructed, which empowers six key technologies with key elements of oil and gas production to realize the essential safety of oil and gas production system. Second, the intelligent safe operation and maintenance technology actively promotes the application and implementation of condition monitoring, health management, risk assessment, intelligent early warning technologies in typical production scenarios such as drilling and extraction, storage and transportation, refining and chemical industry in up, middle and down streams of oil and gas production. Third, in view of the characteristics of oil and gas production system under digital transformation, it is proposed to develop the intelligent safe operation and maintenance technology with the functions of intelligent decision-making, active prevention and comprehensive safety in the future to help the safe construction in the field of oil and gas production and promote the safe and healthy development of the oil and gas industry. In conclusion, the research on intelligent safe operation and maintenance technology system of oil and gas production system is conducive to the safe construction in the field of oil and gas production, which will not only provide technical support for the realization of trouble-free oil and gas production system, but also provide reference for the intelligent development of the world oil and gas industry.

Study of Machine Learning Methods to Predict and Prevent Gas Hydrate Formation

Abstract: Formation of gas hydrates are a serious concern in oil and gas production systems. The formation and possible deposition of hydrates usually occur in suitable conditions, specifically as the gas-phases of reservoir fluid interact with water molecules. Hydrate formation represents a significant risk to process safety as it can result in the plugging of both pipes and instruments. Hydrates typically form in process where light hydrocarbons, water vapor and low temperatures or high pressures are present. We have studied the conditions under which hydrates form, how formation may be prevented and what can be done once hydrates have formed.