Spur Lines Research Articles

Flaring volumes in the intermountain west region: A geospatial analysis of satellite and operator-reported data with viable mitigation strategies

Burning associated gas has been a prevailing problem across the world for decades. This practice consumes billions of (US) dollars' worth of valuable natural gas, contributes billions of metric tons of carbon dioxide (CO2) to the atmosphere, and releases volatile chemicals to nearby communities. To assess the prevalence of wellbore flaring within the Intermountain West (I-West) region, we analyzed data from the Nightfire project and contrasted it with wellbore surface hole locations. Consequently, we will permit the analysis of the flare data on a geospatial scale and compare it with operator self-reported flaring volumes. Through this analysis, we found that New Mexico is by far the largest flaring state in the I-West region, with most of its flare gas coming from the Permian Basin. Additionally, we found that satellite data estimated volumes that were 165% larger than those self-reported by the operators. Although some of this could be an overestimation from the Nightfire project, the size of the discrepancy indicates that there may be an underestimation of flared volumes that operators report to the state. A better understanding of the discrepancy source can be identified by linking the satellite flare volume to individual wells and operators, and potential solutions may be implemented to assist New Mexico's recent waste laws in reducing Permian flared volumes. We also proposed economic solutions that could substantially reduce the flared volume through flare gas utilization through on-site processing, the construction of small spur lines, and the development of a local sink for methane.

Driving Utah's Rivers: Working Water in the West

Driving Utah's Rivers: Working Water in the West

Development of an Integrated Carbon Capture, Utilization, and Storage Hub in the United States

The Integrated Midcontinent Stacked Carbon Storage Hub (IMSCS-HUB) is a first of a kind carbon capture, utilization, and storage (CCUS) project in the midwestern United States. The project is supported under the US Department of Energy’s Carbon Storage Assurance Facility Enterprise (CarbonSAFE) program. The IMSCS-HUB will collect 15 million metric tonnes (MT) per year or more in Iowa and Nebraska and transport it to saline and CO2 enhanced oil recovery (EOR) storage sites in western Nebraska, Kansas, and Texas. Sources include multiple ethanol plants (approximately 1.8 MT/Year), coal fired electric plants (approximately 12.6 MT/Year), and natural gas fired electric plants (approximately 0.6 MT/Year). The passage of an updated tax credit for storage in February 2018 provides a strong economic driver for all of the sources in the hub to develop a hub project. The tax credit provides approximately $50/T for CO2 stored in saline storage units and $35/T for CO2 stored as part of CO2-EOR production. In addition, the inclusion of many bio-energy sources such as ethanol plants allows for early implementation of the project by taking advantage of inexpensive capture ($10/MT to $12/MT) and subsidies from California’s Low Carbon Fuel Standard program. Capture cost estimates for the electric utilities is approximately $33/MT. Transport costs range from $0.6/MT to $5.40/MT. Storage costs range from $3/MT to $4/MT. The hub partners include Battelle, Advanced Resources International, Archer Daniels Midland, Nebraska Public Power District, and others. The region of the project stretching from eastern Iowa to southwestern Nebraska acts as a source corridor, where sources add CO2 to the transport network. The transportation network will consist of a common carrier trunk line designed to connect the largest sources. Smaller sources will be connected through spur lines. The final routing will be selected using the location of existing rights away and environmental factors such as resource locations the critical species habitats. SimCCS and other tools will be used to finalize the routes. The region of the project from southwestern Nebraska to southwest Kansas in a storage corridor where CO2 may be stored in either saline projects or CO2-EOR projects. South of Kansas the CO2 will be transported to Texas for utilization in CO2-EOR. Two saline storage sites and two EOR opportunities have been identified as anchor projects for the storage corridor. The anchor sites are at the northern and southern sides of the storage corridor and will act to validate the storage potential of the entire corridor. In Nebraska saline storage is being planned in Perkins county and CO2-EOR is being studied at Sleepy Hollow Field in Red Willow county. In Kansas, saline storage and CO2- EOR are being planned for Patterson-Heinitz-Hartland (Patterson) Field in Kearney County. Multiple storage formations occur vertically at each site allowing for stacked storage minimizing the surface footprint for monitoring and maximizes the use of storage resources at each site. Data from new tests wells or seismic surveys for each of the sites has been used to create detailed geologic and reservoir models. Modeling for each of the anchor saline sites indicates at least a 50 million tonne storage capacity. The CO2-EOR projects are expected to utilize 2.2 MT and 3.9 MT of CO2 and produce 4.3 and 9.8 million barrels of oil for Sleepy Hollow and Patterson Fields, respectively. The inclusion of CO2-EOR along with saline storage adds an additional economic driver for the project with an estimated revenue of $128/MT and $154/MT of CO2 utilized. The results of the first two phases of the project demonstrate the feasibility of the midcontinent hub concept that couples a diverse set of redundant sources to multiple saline and CO2-EOR projects. The results show that the economics and geology are favorable for early implementation of commercial scale CCUS. The existence of low carbon fuel standard subsidies, storage tax credits, and revenue from produced oil act as economic drivers to support the hub in addition to the climate benefit gained by storing CO2 the hub supports local agriculture and oil production helping to create public support. This presentation will discuss the project development and project economics and how they relate to both stacked saline storage and CO2-EOR in the development of a storage hub. The development of a hub project allows the transport of CO2 from areas such as Iowa that have poor storage potential to areas such as western Nebraska, Kansas, and Texas that have high storage potential. This is critical to the implementation of CCUS in the midcontinent US. The presentation will also discuss the advantage of including redundant sources and sinks to develop a CO2 market that can sustain itself as a commercial enterprise after government funding ends.

The Value of Inter-Regional Coordination and Transmission in Decarbonizing the US Electricity System

Summary Preventing global warming in excess of 1.5°C–2°C requires a transition to zero-carbon electricity systems by midcentury along with the widespread electrification of other sectors. Current state-level renewable portfolio standards and regional transmission arrangements do not capture the benefits of inter-regional transmission or coordination of planning and dispatch for renewable-energy integration. Here, using a co-optimized capacity-planning and dispatch model over 7 years of hourly operation, we show that inter-state coordination and transmission expansion reduce the system cost of electricity in a 100%-renewable US power system by 46% compared with a state-by-state approach, from 135 $/MWh to 73 $/MWh. Sensitivity analyses show that reductions in the cost of photovoltaics, wind, and lithium-ion batteries lead to the lowest electricity costs for systems in which transmission expansion is allowed, while cost reductions for nuclear power or long-duration energy storage lead to greater electricity cost reductions for isolated systems.

A Method for Extracting Some Key Terrain Features from Shaded Relief of Digital Terrain Models

Detection of terrain features (ridges, spurs, cliffs, and peaks) is a basic research topic in digital elevation model (DEM) analysis and is essential for learning about factors that influence terrain surfaces, such as geologic structures and geomorphologic processes. Detection of terrain features based on general geomorphometry is challenging and has a high degree of uncertainty, mostly due to a variety of controlling factors on surface evolution in different regions. Currently, there are different computational techniques for obtaining detailed information about terrain features using DEM analysis. One of the most common techniques is numerically identifying or classifying terrain elements where regional topologies of the land surface are constructed by using DEMs or by combining derivatives of DEM. The main drawbacks of these techniques are that they cannot differentiate between ridges, spurs, and cliffs, or result in a high degree of false positives when detecting spur lines. In this paper, we propose a new method for automatically detecting terrain features such as ridges, spurs, cliffs, and peaks, using shaded relief by controlling altitude and azimuth of illumination sources on both smooth and rough surfaces. In our proposed method, we use edge detection filters based on azimuth angle on shaded relief to identify specific terrain features. Results show that the proposed method performs similar to or in some cases better (when detecting spurs than current terrain features detection methods, such as geomorphon, curvature, and probabilistic methods.

Compact Wideband Meandered Slotted Multi Frequency Microstrip Antenna

A compact wideband multi frequency microstrip antenna for wireless communication is proposed in this paper. The antenna is designed by introducing meandered slot on the patch and a pair of spur lines along the triangular notch on the finite ground plane. The overall size of the fabricated antenna is very small and low profile as the total dimension is 20 × 16 mm2. The proposed antenna operates at 3.7 GHz, 4.27 GHz and 5.1 GHz which may be suitable for WiMAX and WLAN applications. In addition with multi frequency operation a wide bandwidth (VSWR ≤ 2) has been achieved from 6 to 13.7 GHz i.e. 78.2% bandwidth of center frequency, which is suitable for X-band communication and ITU band applications. The meandered slot on the patch causes multi frequency operation of the antenna with 60% compactness and the spur line along with triangular notch on finite ground plane cause bandwidth enhancement.

Design of a miniaturized tri-band bandstop filter using spur microstrip lines and via-hole grounding

PurposeThe purpose of this paper is to propose a miniaturized tri-band bandstop filter that finds application in a modern dense communication system where size and multi-band plays a vital role.Design/methodology/approachIn this paper, the authors propose a miniaturized tri-band microstrip bandstop filter which combines the conventional bandstop filter and spur microstrip line structures such that this design achieves tri-band operation at 1.8 GHz and 3 GHz. The overall length of the microstrip filter is found to reduce from 126 to 45 mm because of introduction of spur lines and via-hole grounding. The addition of spur lines replaces two resonators, introduces two additional resonant frequencies and enhances the −6 dB bandwidth of the center frequency by 14 %.The addition of via-holes in each resonator reduces its length into half of its original length, thereby reducing filter size.FindingsResonance occurs at three different frequencies 1.8, 2.4 and 3 GHz. The filter size reduces from 126 to 45 mm, and the −6 dB rejection bandwidth of center frequency improves by 14 %.Originality/valueThe overall filter size is reduced by 65% and it resonates at three different frequencies 1.8, 2.4 and 3 GHz with an improved bandwidth of 10 % around the center frequency.

Dual-Band Filtering Power Divider Using Dual-Resonance Resonators With Ultrawide Stopband and Good Isolation

In this letter, a novel compact dual-band filtering power divider (DB-FPD) is proposed. It consists of a U-shaped Wilkinson power divider, two pairs of dual-resonance resonators (DRRs), and a pair of spur lines. With the simultaneous use and appropriate design of the coupled feedlines, mixed electric and magnetic couplings between the DRRs and spur-lines with different lengths, multiple transmission zeros are produced which result in two passbands with desired power division, high-frequency selectivity, good isolation, and an ultrawide stopband. A prototype DB-FPD operating at 2.3 and 3.5 GHz with 3-dB fractional bandwidths of 8% and 6% is designed, fabricated, and measured. The measured responses agree well with the design simulations, exhibiting a stopband up to 13.8 GHz ( $6f_{0}$ ) with 20-dB rejection level.

Compact multi frequency strip loaded microstrip patch antenna with spur-lines

In this paper a new design of compact single layered triangular slotted microstrip patch antenna with spur lines and strip loading is proposed. It has been experimentally investigated that strip loading causes more size reduction where spur lines and triangular slot introduces multi frequency operation of microstrip patch antenna. The size reduction has been found to be 87% for the proposed antenna. In this article the effect of strip loading and spur lines over compactness are individually analyzed.

Switchable dual band equilateral triangular microstrip patch antenna using pin diode

Purpose – The purpose of this paper is to study and calculate the electrical characteristic of an equilateral triangular microstrip patch antenna that is proposed for dual frequency operation using the pin diode. The electrical characteristic of an equilateral triangular microstrip patch antenna is proposed for dual-frequency operation. Spur lines and ON/OFF condition of the pin diode are utilized to switch the resonant frequency of the patch. The presence of spur lines excites the surface current of the patch which is dependent on the resonant frequency of an equilateral triangular microstrip patch. Insertion of the diode in the spur lines gives a better result and compactness in patch design, which improves the miniaturization in size of patch. Design/methodology/approach – Antenna Design Aspects: A basic structure of an equilateral triangular microstrip antenna (ETMA) having two spur lines and one pin diode positioned in between the spur line is considered in this paper. The design parameters are chosen on the basis of substrate materials having relative permittivity less than three. Specification of the antenna is given in Table I. Substrate material used is RT Duroid 5,880; relative permittivity of the substrate er is 2.2; thickness of dielectric substrate h is 1.5 mm; sides of equilateral triangular patch a are 10 mm, spur width s is 0.5 mm; and spur length b is 2.0 mm. Findings – This paper gives an account of achieving polarization swiftness with coplanar waveguide (CPW) feed. The miniaturized size of the antenna is 35 × 30 mm2. Switchable microstrip equilateral triangular antenna has been demonstrated for dual-frequency operations. The resonant frequency of an ETMA can be adjusted by setting the diode in an ON and OFF state. The design improves the miniaturization in size with a discussion of radiation density. The excited patch surface current is limited to flow around just the mid of the patch in simple ETMA with a single slit cut. It is observed that for an ETMA, when the diode is in the ON state at 9.16 GHz, the excited patch surface current is highly distributed in the patch compared to when the diode is in the ON state at 11 GHz. Similarly, it is observed that the excited surface patch current is highly distributed when the diode is in the OFF state in both frequencies (9 and 11.96 GHz). The mode is changed by the use of a switch at time and it is suitable for wireless communication applications. Originality/value – Spur lines and the ON/OFF condition of the pin diode are utilized to switch the resonant frequency of the patch. The presence of spur lines excites the surface current of the patch which is dependent on the resonant frequency of an equilateral triangular microstrip patch. Insertion of the diode in spur lines gives a better result and compactness in patch design, which improves the miniaturization in size of the patch.

Design of wide‐stopband microstrip bandpass filter with assistance of spur lines

A novel microstrip bandpass filter with compact size is proposed. With two short-circuited stubs, one open-circuited coupled line using symmetrical feeding, and two spur lines, a wide passband can be obtained. Detailed design and synthesis procedures are provided for filter development. Moreover, the electromagnetic simulator IE3D is used; the prototype of the bandpass filter is consequently fabricated and measured. Agreement between measured results and the theoretical prediction validates the proposed structure.

Design of high selectivity tri-band bandpass filter with wide upper stopband

This article presents a dual-plane structure high selectivity tri-band bandpass filter (BPF) which consists of a pair of T-shaped microstrip feed lines with capacitive source-load coupling as well as spur lines embedded, and three resonators, i.e., a dual-mode stub-loaded stepped impedance resonator and two nested dual-mode defected ground structure resonators. Using the intrinsic characteristics of the resonators and feed lines, nine transmission zeros near the passband edges and in the stopband can be generated to achieve high selectivity. An experimental tri-band BPF located at 2.4/5.7 GHz [wireless local area networks (WLAN) application] and 3.5 GHz [worldwide interoperability for microwave access (WiMAX) application] has been simulated and fabricated. Good agreement between the simulated and measured results validates the design approach. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.

Novel compact low temperature cofired ceramic ultrawideband SIR bandpass filter using different coupling schemes

AbstractA new ultrawideband quarter‐wavelength SIR filter using different coupling schemes is presented. In the proposed filter, weak coupling coefficient is realized using conventional edge‐coupled structure, while great coefficient is obtained by applying direct magnetic coupling between two resonators or overlapping resonators in different low temperature cofired ceramic layers. Based on the proposed strong coupling structures, the bandwidth is extended, while the size is largely reduced. Besides, spur lines are adopted to improve the stopband characteristic. In this article, a four‐pole filter of dimension 0.11λg × 0.18λg, with a 3‐dB bandwidth of 74.5% and a wide stopband up to 12 GHz, is designed and fabricated. Good agreement between measured and simulated results is observed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:967–970, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26679

Improving performance of non-duplexer active transceiver antenna with defected structures

The implementation of an active transceiver patch antenna without duplexer is reported. The isolation of the transmitting-receiving ports is increased by almost 20 dB by using defected ground structure patterns obtaining more than 50 dB; besides, cross-polarisation levels are also decreased by more than 15 dB. On the other hand, the use of spur lines allows increasing the linearity of the transmitting path, obtaining a low-harmonic distortion class E power amplifier. In the receiving path, a high-linear low noise amplifier (LNA) is employed with a third-order input intercept point close to 20 dBm. Both amplifiers are built with heterounion bipolar transistor (HBT). To prove the idea, as an example, the operation frequencies and channel separation of the GSM1800 were taken into account for a practical design. The complete active antenna is developed with characteristic impedances different from 50 Ω to obtain optimal performance of the active blocks.

Traffic pattern analysis for spur lines

In a mass transit railway environment with spur lines, the interleaving of trains along different branches and the layover time at different termini could have a significant impact on fleet size and hence cost. These operational parameters could be systematically optimized without affecting the planned service levels.

Compact tri‐band BPF design using spur‐line‐loaded tri‐section SIRs

AbstractIn this article, a new tri‐band microstrip bandpass filter (BPF) is proposed. The BPF is composed of two folded, rectangular‐shaped three‐section SIRs (TSSIRs) whose first three resonant frequencies can be tuned to locate in the desired passbands. The BPF are 0° fed and the end sections of the TSSIRs are designed in an antiparallel fashion to produce zeros at appropriate frequencies for improving passband selectivity. In addition, by embedding spur lines and defected ground structures (DGS) in the BPF, extra transmission zeros around the first spurious passband are introduced to widen the upper stopband. The designed BPF is fabricated on an RT/Duroid 6010 substrate. The measured fractional bandwidths (minimum insertion losses) for the 1.57 GHz (GPS), 2.45 GHz (ISM), and 3.5 GHz (WiMAX) bands, respectively, are 11.5% (1 dB), 4.6% (2.19 dB), and 10.9% (1.3 dB), which agree well with those predicted by simulation. It also shows that for miniaturization purposes, the TSSIRs are made meandered to give an overall circuit size of only 23.29 × 10.94 mm2 for the designed BPF. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 989–991, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24208

Analysis and Design of Two Layered Ultra Wide Band Filter

Design of an Ultra Wide Band (UWB) filter over 3.1 GHz to 10.6 GHz using broad side coupled and spur lines in microstrip medium suitable for UWB communications has been presented in this paper. Parameters of broad side coupled lines have been appropriately chosen to achieve ultra wide band response. Spur lines have been incorporated at the input and output feed lines of the filter to improve the stop band rejection characteristics of the filter. Filter has been analyzed based on circuit models and full wave simulations. Experimental results of the filter designed using the proposed structure has been verified against the results obtained from circuit models and full wave simulations. The results match satisfactorily. Stop band rejection of better than 20 dB was obtained over the frequencies of 13 GHz to 18.2 GHz. Overall size of the filter is 40 × 18 × 0.787 mm3.

MMR-based Band-notched UWB Bandpass Filter Design

A new band-notched ultra-wideband (UWB) bandpass filter (BPF) with an improved upper stopband is designed using a multi-mode resonator (MMR). The MMR, being a modified version of a common tri-section stepped-impedance resonator (TSSIR), is split at its two open ends with the input/output feed lines sandwiched in between to form an interdigital parallel-coupled configuration that results in stronger coupling. In addition, an extended coupling length in the second section of the TSSIR is featured to provide further coupling and impedance-matching tuning. With such a design strategy, coupling gaps of no smaller than 0.1 mm was achieved to obtain the required UWB response. In this design, the first five resonant modes of the MMR and the coupling peaks of the input/output parallel-coupled lines are properly located in the UWB passband to achieve a uniform in-band transmission response. Also, the spur lines and open-circuited stubs are implemented in the MMR to create a 5-GHz notched band and to broaden the upper stopband, respectively. The designed UWB BPF, which being verified by measurement, shows a very good UWB performance. The measured in-band minimum insertion loss and maximum group delay variation except those in the notched band are 0.45 dB and 0.05 ns, respectively, and the upper-end −20-dB stopband bandwidth is about 5.35 GHz. The created notched band is centered at 5.69 GHz with a maximum insertion loss of 37.2 dB and a 3-dB notch bandwidth of 18%.

Parallel‐coupled microstrip bandpass filters with a wide stopband using spur lines

AbstractIn this paper, we propose a novel parallel‐coupled microstrip bandpass filter with a wide stopband. The proposed bandpass filter with spur lines provides a deep and wide stopband because spur lines can provide deep stopband characteristics in some frequency bands. Also, the experimental results show that the transmission coefficients of the proposed filter are lower than −50 dB around the 2nd‐ and 3rd‐harmonic frequencies. This operation can be obtained without increasing its size while the other features are not degraded. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 9–11, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20359

The use of a pair of spur lines for broadband circular microstrip antenna with embedded reactive loading

This communication demonstrates the use of a pair of spur lines for a broadband circular microstrip antenna with an embedded reactive loading. With the use of the spur lines, the impedance bandwidth of the proposed design can be enhanced. The obtained bandwidth can reach up to 112.5 MHz, which is about 1.32 times that (86 MHz) of the original broadband antenna without spur lines. The variations in antenna gain within the impedance bandwidth are also less than 2 dBi. Details of the proposed design are described, and experimental results of the antenna performance are presented and discussed.