scholarly journals A Simulation Study of the Effect of Injecting Carbon Dioxide with Nitrogen or Lean Gas on the Minimum Miscibility Pressure

2021 ◽  
Author(s):  
Ahmed GH Mansour ◽  
Talal Gamadi ◽  
Hussain R Saoyleh

Abstract The objective of this study is to determine the effects of the concentration of injected gases on recovery factors. CO2 has been used for flooding because it requires low injection pressures to achieve miscibility. However, the availability of CO2 is an issue. CO2 required for the process is not sufficient for the reservoir under consideration. Moreover, its benefit-cost ratio (b/c) represents another issue; higher volumes of CO2 increases the economic expenditures. An alternative is to inject lean gas or nitrogen along with CO2 to achieve better recoveries at optimum costs and suitable pressure. Slim tube simulation using a commercial simulator is utilized to measure the minimum miscibility pressure (MMP) of an injected gas mixture. The mixture contains CO2/N2 or CO2/lean gas. Using different concentrations in the injected mixture, an effect on the recovery factor is studied. The first 30 runs have 100% concentration of each individual gases i.e. N2, CO2 and lean gas. Based on these runs, the simulation model is validated using the co-relations present in the literature. Gas mixtures of CO2/N2 and CO2/lean gas were then simulated using the compositional model to test the effect on MMP by varying the concentration of each gas in the mixture. By changing the volumes of the gas in the injected mixture, we can find the optimum concentration of each component in the mixture in terms of MMP. From the results obtained through simulation, it can be deduced that higher percentages of CO2 in the mixture would result in reduced minimum miscibility pressure. The addition of a secondary slug to the injected CO2 fluid increases the pressure required to achieve miscibility. Of N2 and Lean gas, Lean gas provided better results as it showed low miscibility pressure responses compared to the same amount of N2 gas. For example, for a case, 50% CO2 and 50 %N2 or lean gas mixture, the MMP for the lean gas mixture is 3500 Psi, while for N2 mixture it was 4667 Psi. However, lean gas is expensive as compared to N2 and N2 is easily available. N2, if used in optimum concentration along with CO2 can produce greater recoveries keeping the process cost-effective while satisfying other constraints. CO2 is widely used for miscible injection, but it presents problems like costs, corrosion, and asphaltene deposition etc. The study can give an idea of the success of carrying out EOR through gas flooding by using N2 and CO2 to enhance recovery at low cost. N2 is easily available from air and it is cheap.

2020 ◽  
pp. 096228022095817
Author(s):  
Linchen He ◽  
Linqiu Du ◽  
Zoran Antonijevic ◽  
Martin Posch ◽  
Valeriy R Korostyshevskiy ◽  
...  

Previous work has shown that individual randomized “proof-of-concept” (PoC) studies may be designed to maximize cost-effectiveness, subject to an overall PoC budget constraint. Maximizing cost-effectiveness has also been considered for arrays of simultaneously executed PoC studies. Defining Type III error as the opportunity cost of not performing a PoC study, we evaluate the common pharmaceutical practice of allocating PoC study funds in two stages. Stage 1, or the first wave of PoC studies, screens drugs to identify those to be permitted additional PoC studies in Stage 2. We investigate if this strategy significantly improves efficiency, despite slowing development. We quantify the benefit, cost, benefit-cost ratio, and Type III error given the number of Stage 1 PoC studies. Relative to a single stage PoC strategy, significant cost-effective gains are seen when at least one of the drugs has a low probability of success (10%) and especially when there are either few drugs (2) with a large number of indications allowed per drug (10) or a large portfolio of drugs (4). In these cases, the recommended number of Stage 1 PoC studies ranges from 2 to 4, tracking approximately with an inflection point in the minimization curve of Type III error.


2018 ◽  
Vol 69 (5) ◽  
pp. 479 ◽  
Author(s):  
Nauman Ali ◽  
Muhammad Farooq ◽  
Muhammad Ahmad Hassan ◽  
Muhammad Shakeel Arshad ◽  
Muhammad Kamran Saleem ◽  
...  

Agronomic biofortification by seed treatments is a convenient way to harvest improved yields of micronutrient-enriched grains. This 2-year field study was conducted to evaluate the effects of seed priming with zinc (Zn), boron (B) and manganese (Mn) alone and in combinations on stand establishment, grain yield and biofortification of bread wheat (Triticum aestivum L.). Seeds of wheat cv. Faisalabad-2008 were soaked in aerated solutions of 0.5 m Zn, 0.01 m B and 0.1 m Mn, alone and in different combinations, for 12 h. Seed priming with the micronutrients was quite effective in improving stand establishment, yield-contributing traits, grain yield, and straw and grain micronutrient contents during both years. Best stand establishment was achieved from seed priming with Zn+B, followed by seed priming with Zn+Mn. Grain yield improvement from different seed priming treatments was in the order Zn+B > Zn+Mn > Zn > B > Mn > Zn+B+Mn, with respective increases of 34%, 33%, 21%, 19%, 18% and 8% relative to untreated seeds. Seed priming with Zn, B and Mn alone and in combinations also improved the contents of the respective micronutrients in straw and grain. All seed priming treatments were economically profitable except Zn+B+Mn, which was not cost-effective. The highest benefit : cost ratio accrued from seed priming with Zn+B. In conclusion, seed priming with micronutrients was generally cost-effective in meeting the crop micronutrient requirements, and in improving crop stand, grain yield and grain micronutrient contents in bread wheat. Seed priming with Zn+B was the most effective in this regard.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Steve J. Merrill ◽  
Alexander Paz ◽  
Victor Molano ◽  
Pramen P. Shrestha ◽  
Pankaj Maheshwari ◽  
...  

This study provides an economic evaluation for a Land Ferry, which is a rail system capable of carrying trucks and all other types of vehicles, passengers, and cargo. The Land Ferry system involves a sliding loading system to roll heavy loads onto a flatbed; as a result, loading and unloading of all vehicles and cargo could be accomplished simultaneously. The evaluation for this system included (1) the design of a new track alignment over which the Land Ferry system would run, (2) evaluation of various sources of power, (3) estimation of how many local jobs the Land Ferry would generate, and (4) a benefit-cost analysis. It was estimated that the Land Ferry would create over 45,788 temporary jobs in Nevada during the three-year construction period and 318 permanent jobs during operation. The majority of the benefits were attributed to savings in travel time ($356.4 M), vehicle operating costs ($1000.4 M), reduction of accidents ($544.6 M), and pavement maintenance ($503.2 M). These benefits would be a consequence of the shift of trucks from the highway, thus resulting in higher speeds, decrease fuel consumption, and decrease vehicle maintenance costs. The overall benefit-cost ratio of 1.7 implies a cost-effective project.


2014 ◽  
Vol 663 ◽  
pp. 596-603
Author(s):  
Zulhaidi Mohd Jawi ◽  
Aqbal Hafeez Ariffin ◽  
Yahaya Ahmad ◽  
Khairil Anwar Abu Kassim ◽  
Norlen Mohamed ◽  
...  

The newly established New Car Assessment Program for Southeast Asian Countries (ASEAN NCAP) has incorporated Safety Assist Technologies (SATs) in its automobile safety rating scheme. In order for any assessed car to be eligible for the maximum 5-star rating, it should first be equipped with Electronic Stability Control (ESC) and fitted with seatbelt reminder (SBR). However, since these SATs are not being evaluated in their performance by the means of field testing, this paper explains the benefit of having these SATs through Cost-Benefit Analysis (CBA) which help to rationalize the importance of SATs in preventing road accidents or mitigating severity of injuries. Due to data limitation, this preliminary CBA assessment will only be focusing on Malaysia’s situation and is based on published sources and the authors’ best estimates. This study also includes the Cost-Benefit Analysis on Anti-lock Braking System (ABS), which is the basis for ESC technology, in preparation for its inclusion in the future rating scheme to expedite the vision of making ABS as standard fit in all ASEAN’s passenger cars. The preliminary result shows that all technologies – ESC, SBR and ABS – appear to be cost-effective (benefit/cost-ratio > 3) or most likely cost effective (1 < benefit/cost-ratio < 3) in Malaysia’s road safety situation per se.


2013 ◽  
Vol 5 (2) ◽  
pp. 205-207
Author(s):  
MM Karim ◽  
MSU Bhuiya ◽  
BC Das ◽  
SMA Hossain

A field experiment was conducted at the farmers’ field of Livelihood Improvement of Farming Community in Haor Area through System Approach Project site Purbo Tethulia, Mohangonj, Netrakona during the Rabi Season of 2011-2012 to shorten the field duration of potato through seed pre-sprouting technique and to find out the suitable potato variety for cultivation in Dingaputa haor area without affecting the cultivation period of boro rice. Diamont and one local variety Challisha were taken for the study. Pre-sprouting duration of Diamont was 10, 20, 30 and 40 days with un-sprouted Diamont and Challisha. In the study unsprouted Diamont produced significantly the highest yield (25.28 tha-1) followed by 20.01, 13.46, 13.31, 12.74 and 11.54 tha-1 of 10, 20, 30, 40 days pre-spouted Diamont and un-sprouted Challisha, respectively. The lowest field duration of the crop was 41 days of 30 and 40 days pre-spouted Diamont. The highest gross margin of Tk.165960 ha-1 was observed from the unsprouted Diamont potato against the variable cost of Tk.137400 ha-1 incurred. The performance of Challisha was also appreciated by the farmers for its quality and low cost of production. Unsprouted Diamont potato also ranked the top most position in terms of benefit cost ratio of 2.21.DOI: http://dx.doi.org/10.3329/jesnr.v5i2.14815 J. Environ. Sci. & Natural Resources, 5(2): 205-207 2012


Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 899 ◽  
Author(s):  
Andreia dos Santos ◽  
Nuno Pinela ◽  
Pedro Alves ◽  
Rodrigo Santos ◽  
Ricardo Farinha ◽  
...  

Electronic skin (e-skin) is pursued as a key component in robotics and prosthesis to confer them sensing properties that mimic human skin. For pressure monitoring, a great emphasis on piezoresistive sensors was registered due to the simplicity of sensor design and readout mechanism. For higher sensitivity, films composing these sensors may be micro-structured, usually by expensive photolithography techniques or low-cost and low-customizable molds. Sensors commonly present different sensitivities in different pressure ranges, which should be avoided in robotics and prosthesis applications. The combination of pressure sensing and temperature is also relevant for the field and has room for improvement. This work proposes an alternative approach for film micro-structuration based on the production of highly customizable and low-cost molds through laser engraving. These bimodal e-skin piezoresistive and temperature sensors could achieve a stable sensitivity of −6.4 × 10−3 kPa−1 from 1.6 kPa to 100 kPa, with a very robust and reproducible performance over 27,500 cycles of objects grasping and releasing and an exceptionally high temperature coefficient of resistance (TCR) of 8.3%/°C. These results point toward the versatility and high benefit/cost ratio of the laser engraving technique to produce sensors with a suitable performance for robotics and functional prosthesis.


2014 ◽  
Vol 12 (1) ◽  
pp. 167-170
Author(s):  
MA Islam ◽  
MD Hussain ◽  
E Kabir ◽  
MZ Hasan

This experiment was conducted to bring in a suitable and economic agarwood oil extraction method for Agar tree (Aquilaria agollocha) growers in Bangladesh. Agarwood was collected from Fotikchori upazila of Chittagong district and a prototype of hydro-distillation extraction chamber was developed at the lab of Department of Farm Power and Machinery, Bangladesh Agricultural University, Mymensingh, Bangladesh during January to March 2013. Using the prototype, 7 ml of agarwood oil was extracted from 15 kg matured agarwood. It was found from the calculation that the developed system can bring yearly benefit of Tk. 7,78,389 with benefit-cost ratio as 2.33. This development was, therefore, proven very beneficial for Bangladeshi agar tree growers. DOI: http://dx.doi.org/10.3329/jbau.v12i1.21407 J. Bangladesh Agril. Univ. 12(1): 167-170, June 2014


2020 ◽  
Vol 3 (1) ◽  
pp. 198-208
Author(s):  
Mousami Poudel ◽  
Prabin Adhikari ◽  
Suryamani Dhungana ◽  
Shankar Paudel ◽  
Kanti Thapa ◽  
...  

A study was conducted to examine cost structure and economic feasibility of rubber production in Jhapa district. It also aimed to assess determinants of increment in acreage of rubber cultivation in the study area. A total of sixty two rubber growers were selected by simple random sampling and interviewed with pre-tested semi structured schedule on the month of March, 2019. Study revealed that the total cost of natural rubber production per hectare of rubber orchard was 499774.8 NRs. /year. It was found to be economically viable and cost effective as indicated by satisfactory values of Benefit Cost Ratio (1.5), Net Present Value of NRs. 686547 at a discount rate of 12 percent and Internal Rate of Return 18 percent. Probit model revealed that trainings received, experience of rubber farming, ethnicity and membership in community organizations were significant factors that positively affected farmers’ decision in expanding rubber cultivation area. Received trainings solely could increase probability of acreage increment by 36.9 percent. Thus, it is recommended that extension services like training, farmers’ field school, and farm visits should be intensified for increment of profitability from rubber farming in Jhapa, Nepal.


2021 ◽  
Vol 6 (7) ◽  
pp. 91-96
Author(s):  
Md. Janibul Alam Soeb ◽  
Muhammad Rashed Al Mamun ◽  
Shamima Shammi ◽  
Minhaj Uddin ◽  
Rukon Ahmed Eimon

In this study, a poultry egg incubator was designed, fabricated, and tested to evaluate its hatching performance. The incubator consists of a microcontroller with egg turner trays and incubating chamber of 116 nos. of egg capacity. The hatchability of the developed incubator was 79.3% and 87.1% hatchability during manual and automatic trials respectively. The temperature in the developed incubator was within the acceptable incubation temperature ranges from 37.6 °C to 38.6 °C. The average relative humidity in the developed incubator was maintained at 63.6% at manual and 55-65% at automatic trial. The eggs were turned manually approximately at 6 hours of interval. On the other hand, in the automatically controlled trial, it was done by egg turner maintaining exactly 6 hours of interval. It is noted that the percentage of hatching in rice husk incubators is below 55% which is much below comparing with the developed incubator. Also, the newborn chickens in rice husk incubators are unhealthy as they don’t get a sufficient amount of heat. Besides, in the sand incubation technique, kerosene-based hurricane lamps are used which produce Carbon Dioxide. The developed incubator is environment friendly because it doesn’t produce any by-product that is responsible for harming the environment. Also, after the successful trials, we have found the benefit-cost ratio was 1.42 which was quite satisfactory. The egg incubator can maintain the optimum conditions for the hatching of the chicken eggs and is capable of incubating and hatching the chicken eggs effectively. If the developed incubator is commercially supplied to the end-user, it will be a beneficial process of hatching for the farmer of Bangladesh.


Author(s):  
Thanh Q. Le ◽  
Frank Gross ◽  
Timothy Harmon

Packages of intersection treatments—including signing, pavement marking, and signal enhancements—were installed at many signalized and stop-controlled intersections in South Carolina. This study evaluated the overall safety-effectiveness of the concurrent implementation of these systemic low-cost treatments as part of the FHWA Evaluations of Low Cost Safety Improvements Pooled Fund. The data set included both urban and rural three-leg and four-leg intersections with two or four lanes on the major road. The study employed an empirical Bayes before-and-after analysis. The aggregate results indicate reductions for all crash types analyzed in this study. For signalized intersections, the crash modification factors (CMFs) are 0.955, 0.893, 0.974, 0.883, and 0.969 for total, fatal and injury, rear-end, right-angle, and nighttime crashes, respectively. The CMFs for fatal and injury and right-angle crashes are statistically significant at the 95% confidence level and the CMF for total crashes is statistically significant at the 90% confidence level. For stop-controlled intersections, the CMFs are 0.917, 0.899, 0.933, 0.941, and 0.853 for total, fatal and injury, rear-end, right-angle, and nighttime crashes, respectively. All CMFs for stop-controlled intersections are statistically significant at the 95% confidence level. An economic analysis shows that systemic, low-cost intersection treatments are cost-effective with conservative benefit–cost ratio estimates of 4.1 for total crashes at signalized intersections and 12.4 for total crashes at stop-controlled intersections.


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