Impacts of H2 Blending on Capacity and Efficiency on a Gas Transport Network

2019 ◽  
Author(s):  
Francis Bainier ◽  
Rainer Kurz
Keyword(s):  
Natural Gas ◽  
Molecular Hydrogen ◽  
Gas Transport ◽  
Energy Requirement ◽  
Calorific Value ◽  
Hydrogen Gas ◽  
Transport Network ◽  
Pure Hydrogen ◽  
Pipeline Network ◽  
Methane Gas

Abstract Gas Transport System Operators (TSO1) are considering injecting hydrogen gas in their networks. Blending hydrogen into the existing natural gas pipeline network appears to be a strategy for storing and delivering renewable energy to markets [1], [2],[3]. In comparison to methane, hydrogen gas (dihydrogen or molecular hydrogen) has a higher mass calorific value than methane gas. Because of this property, molecular hydrogen is appreciated for space shuttle engines. A second property is that hydrogen gas has a lower mass density than methane gas. The result of the second property is that the volume calorific value is in favor of methane gas. The list of differences between methane and hydrogen is long. In the relevant range of pressures and temperatures, the Joule-Thomson coefficient has a different sign for hydrogen and methane, and the compressibility factor has the opposite trend when the gas is compressed. The dynamic viscosity is also significantly different, and finally, heat capacity, isentropic exponent, and the thermal conductivity are also different. What are the impacts of these hydrogen characteristics on the transport capacity and its efficiency in the case of blending in a gas transport network? The first part of the paper is a review of the differences in characteristics between Hydrogen Gas and a Typical Natural Gas in Europe and their impact on the gas flow performance in a pipeline network equipped with compressors. The second part of the paper is dedicated to pipe segments. And in the third part, compressor stations are introduced between each pipe segment. At each step, an analysis of a mixed gas from one hundred per cent pure natural gas to one hundred per cent pure hydrogen is done. The paper provides some results for 10 %, 40 %, and 100 % of hydrogen blending in an international pipeline. The study shows that the energy quantity transported at the same pressure ratio is reduced respectively by 4 %, 14 %, and 15 to 20 %, and energy requirement for compression increases respectively by 7 %, 30 %, and 210 % (i.e. it more than triples). To transport the same quantity of energy in a network, assuming the resizing to the same level of optimizations, the energy requirement increases by 11 %, 52 %, and 280 %. In other words, it takes 4 times the energy to transport a given amount of energy if the gas is pure hydrogen than it takes if the gas is pure natural gas. The paper does not address the issue of equipment or material, it only compares the influence of hydrogen gas on the network capacity and the transport efficiency. This paper doesn’t take into account the limits of the equipment. All equipment is considered as compatible with any load of hydrogen blending.

scholarly journals Simulation of the operation of a natural gas transport system based on a criterion of minimum operating cost

DYNA ◽  
2019 ◽  
Vol 86 (211) ◽  
pp. 308-316
Author(s):  
Jaime Fernando Andrade Mahecha ◽  
Grigory Ibrahim Massy Sánchez
Keyword(s):  
Natural Gas ◽  
Gas Transport ◽  
Operating Cost ◽  
Transport Network ◽  
Operating Costs ◽  
System Of Equations ◽  
Linear Programming Methods ◽  
Natural Gas Transport ◽  
The Cost ◽  
Minimum Operating

In this article, a simulation model of a natural gas transport network based on the minimization of its operating costs was developed. For this, a system of equations that determine these costs and the conditions that characterize it are established, to later be transformed into a system that can easily be solved by common linear programming methods. A system of equations and matrices resulting from a transport network of few elements is presented as an example. The model is applied in the simulation of the future operation of the Colombian natural gas transport network to project the cost of its operation, section flows, its associated tariffs, and shortage level. Finally, the conclusions derive possible use applications of this model for the analysis of natural gas transport networks and other energy systems.

scholarly journals On the Star Formation in Early Stage of Galactic Evolution

1981 ◽  
Vol 93 ◽  
pp. 68-69
Author(s):  
Y. Yoshii ◽  
Y. Sabano
Keyword(s):  
Molecular Hydrogen ◽  
Thermal Instability ◽  
Heavy Element ◽  
Hydrogen Gas ◽  
Initial Mass Function ◽  
Element Abundance ◽  
Subsequent Stage ◽  
Pure Hydrogen ◽  
Wide Range ◽  
Gas Cloud

Evolution and fragmentation of a gas cloud are investigated for the primordial chemical composition which is the same as the products of the Big Bang. A pure-hydrogen gas cloud collapses isothermally at 500–1000 K when a low fraction of molecular hydrogen works as a coolant, and breaks into small subcondensations with mass less than 10 M⊙ due to thermal instability associated with molecular dissociation. On the other hand a pure-hydrogen gas cloud which contains no molecular hydrogen collapses isothermally at 6000–8000 K in a thermally stable condition, and enters the region where thermal energy exceeds radiation energy when thermal equilibrium between matter and radiation is achieved in the cloud. Consideration of energetics in the subsequent stage of the cloud evolution leads to the mass range of 0.1–20 M⊙ for the stable nuclear-burning protostars of the first generation. The thermal behavior of a gas cloud in the regime of z (the ratio of heavy element abundance to solar one) less than 10−4 is essentially similar to that in the case of no heavy element, and the heavy element cooling brings about thermal instability in a wide range of parameters in the regime of z greater than 10−3. Linear perturbation analysis gives growth time of the instability much shorter than the free-fall time, and suggests the efficient excitation of density fluctuation driven by thermal instability. Thus the possibility of the initial mass function relatively enhanced in massive star at early times is denied, and the slow rate of metal enrichment in the interstellar medium is suggested.

Transportation of Hydrogen Gas From a Local Plant to Remote Markets via High Pressure Submarine Pipelines

2017 ◽  
Author(s):  
Morten Hval ◽  
Stig Vemund Gråberg
Keyword(s):  
High Pressure ◽  
Natural Gas ◽  
Energy Demand ◽  
Distribution Systems ◽  
Electric Energy ◽  
Hydrogen Gas ◽  
Gas Pipeline ◽  
Pure Hydrogen ◽  
Submarine Pipeline ◽  
End User

Hydrogen is about to become a very important energy carrier. It is regarded as clean since its only bi-product is water when it is converted to electric energy in a fuel cell. Hydrogen gas needs, however to be transported to the end user from the hydrogen plant. If the end user is remote from the plant and the total energy demand is high, the hydrogen gas is best transported through a pipeline. Low pressure hydrogen gas pipeline distribution systems already exist onshore and have been in operation for years both in Europe and USA. REINERTSEN has performed a study to evaluate the possibilities for transporting pure hydrogen gas or natural gas/hydrogen mixtures under high pressure through a submarine pipeline from an onshore plant to an end-user either offshore or overseas from where the hydrogen gas is produced. Hydrogen under high pressure is known to have some possible detrimental effects with respect to material brittleness and enhancement of fatigue crack growth which must be carefully considered before a steel submarine pipeline is constructed and installed. The severity of the detrimental effect may be attributed to both the material type and welding procedure, something which must also be taken into the consideration. This paper is devoted to the possible changes and limitations in material properties caused by pressurized hydrogen gas that must be considered when designing and installing a submarine transport pipeline or converting an existing natural gas pipeline to hydrogen service.

Design and Performance Analysis of a 1 MW Solid Oxide Fuel Cell System for Combined Production of Heat, Hydrogen, and Power

2011 ◽  
Author(s):  
William L. Becker ◽  
Robert J. Braun ◽  
Michael Penev
Keyword(s):  
Fuel Cell ◽  
Hydrogen Production ◽  
Capital Investment ◽  
Energy Requirement ◽  
Unit Cost ◽  
Hydrogen Separation ◽  
Hydrogen Gas ◽  
Performance Estimation ◽  
Pure Hydrogen ◽  
And Performance

SOFC systems with co-generation exhibit high overall efficiency. Fuel cell-based co-generation studies have typically focused on electricity and heat; pure hydrogen gas can also be generated in these systems as an energy co-product resulting in the combined production of heat, hydrogen, and power (CHHP). Co-locating a distributed generation SOFC CHHP plant with fueling stations for fuel cell vehicles enables use of lower scale (200 kg/day) hydrogen production and leverages the capital investment among all co-products, thereby lowering the unit cost of hydrogen and offering a potentially promising transition pathway to a hydrogen economy. This work focuses on the design and performance estimation of a methane-fueled 1 MW SOFC CHHP system operating at steady-state. System design and modeling are carried out employing Aspen Plus™ software where performance characteristics of the SOFC and the balance-of-plant are estimated from industry and literature sources. Analysis of the SOFC CHHP system indicates that the SOFC electrochemical performance is independent of the heat recovery and hydrogen production processes because the latter two subsystems are downstream of the SOFC power module. The system is configured such that it can preferentially produce hydrogen or low-temperature thermal energy (80 °C) as needed. Two methods of hydrogen purification and recovery from the SOFC tail-gas were analyzed: pressure swing adsorption (PSA) and electrochemical hydrogen separation (EHS). The recovered hydrogen is compressed to 425 bar for storage. The SOFC electrical efficiency at rated power is estimated at 48.1% (LHV) and the overall CHHP efficiency is 84.4% (LHV) for the EHS design concept. The amount of hydrogen recovery (85–90%) with EHS is higher than PSA for typical SOFC effluent gas compositions. The hydrogen separation energy requirement of 2.7 kWh/kg H2 for EHS is found to be about three times lower than PSA in this system. Increasing the amount of hydrogen production can be independently controlled by flowing excess methane into the system, effectively decreasing SOFC fuel utilization yet still reforming the fuel to a hydrogen-rich syngas. A case study for hydrogen overproduction is given. Operating the system to produce excess hydrogen increases the efficiency for both hydrogen separation design concepts.

scholarly journals Optimization of natural gas transport pipeline network layout: a new methodology based on dominance degree model

Transport ◽  
2018 ◽  
Vol 33 (1) ◽  
pp. 143-150 ◽  
Author(s):  
Zhenjun Zhu ◽  
Chaoxu Sun ◽  
Jun Zeng ◽  
Guowei Chen
Keyword(s):  
Natural Gas ◽  
Gas Transport ◽  
Rapid Development ◽  
Optimal Solution ◽  
Zhejiang Province ◽  
Practical Significance ◽  
Pipeline Network ◽  
Network Layout ◽  
Pipeline Networks ◽  
Natural Gas Transport

At the phase of 13-th five-year plan in China, natural gas will play an important role in energy revolution. With the growth of consumption, natural gas infrastructures will become hot spots of future investment and pipeline network construction will also usher in a period of rapid development. Therefore, it is of great theoretical and practical significance to study layout methods of transport pipeline network. This paper takes natural gas transport pipeline network as a research object, introduces dominance degree to analyse benefits of pipeline projects. Then, this paper proposes Dominance Degree Model (DDM) of transport pipeline projects based on Potential Model (PM) and Economic Potential Theory (EPT). According to DDM of gas transport pipeline projects, layout methods of pipeline network are put forward, which is simple and easy to obtain the overall optimal solution and ensure maximum comprehensive benefits. What’s more, construction sequences of gas transport pipeline projects can be also determined. Finally, the model is applied to a real case of natural gas transport pipeline projects in Zhejiang Province, China. The calculation results suggest that the model should deal with the transport pipeline network layout problem well, which have important implications for other potential pipeline networks not only in the Zhejiang Province but also throughout China and beyond.

Premixing Air and LCV Gas in a Gas Turbine Compressor

2002 ◽  
Author(s):  
M. C. van der Wel ◽  
M. Kramer ◽  
J. P. van Buijtenen
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Pressure Ratio ◽  
Calorific Value ◽  
Hydrogen Gas ◽  
Matching Problems ◽  
Flow Balance ◽  
Compressor Pressure Ratio ◽  
Surge Line ◽  
Gas Turbine Compressor

When a gas turbine is operated on low calorific value (LCV) gas instead of natural gas, the operating point of the compressor will shift towards the surge line. The compressor pressure ratio can rise to a level where stall or surge can occur. Premixing LCV gas with air inside the compressor of a gas turbine can solve this problem. With all fuel premixed, no fuel needs to be injected through the normal fuel inlet. The mass flow balance between turbine and compressor is restored and matching problems will not occur. From calculations with two LCV gases it could be concluded that all LCV gas could be premixed with compressor air when a low percentage of hydrogen gas was present in the LCV gas. The LCV gas could not be fully premixed in case of a high amount of hydrogen. The calculations show that an OPRA OD 500 gas turbine operated on premixed LCV gas with a low amount of hydrogen can maintain its original efficiency and a loss of 14 efficiency points can be prevented.

scholarly journals Uncertainty Analysis for Natural Gas Transport Pipeline Network Layout: A New Methodology Based on Monte Carlo Method

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Jun Zeng ◽  
Chaoxu Sun ◽  
Zhenjun Zhu ◽  
Jiangling Wu ◽  
Hongsheng Chen
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Natural Gas ◽  
Uncertainty Analysis ◽  
Gas Transport ◽  
Zhejiang Province ◽  
Pipeline Network ◽  
Network Layout ◽  
Pipeline Networks ◽  
Natural Gas Transport

Natural gas plays an increasing important role in the China’s energy revolution. The rapid market development and refined government regulation demand improvements in the natural gas transport pipeline network. Therefore, it is of great theoretical and practical significance to conduct a study regarding the layout of pipeline networks. To reflect the comprehensive benefits of pipeline projects and obtain global optimal solution, this study introduces the dominance degree model (DDM). Aiming at optimizing the layout of natural gas transport pipeline networks, this paper studies the uncertainty of the DDM and the corresponding method for network layout. This study proposes an uncertainty analysis based on the Monte Carlo method to quantify the uncertainty of the DDM and its influential factors. Finally, the methodology is applied to the real case of a natural gas transport pipeline project in Zhejiang Province, China. The calculation results suggest that the methodology appropriately addresses the problem of pipeline network layout for natural gas transport. This has important implications for other potential pipeline networks not only in the Zhejiang Province but also throughout China and beyond.

scholarly journals Managing the Pressure to Increase the H2 Capacity Through a Natural Gas Transmission Network

2020 ◽  
Author(s):  
Francis Bainier ◽  
Rainer Kurz ◽  
Philippe Bass
Keyword(s):  
Natural Gas ◽  
Partial Pressure ◽  
Gas Flow ◽  
Network Capacity ◽  
Hydrogen Gas ◽  
Gas Pipeline ◽  
Pipeline Network ◽  
Gas Network ◽  
Natural Gas Pipeline ◽  
Partial Pressures

Abstract Gas Transmission System Operators (TSO1) are considering injecting hydrogen gas into their networks. Blending hydrogen into the existing natural gas pipeline network appears to be a strategy for storing and delivering renewable energy to markets [1], [2], [3]. In the paper GT2019-90348 [4], the authors have explored the efficiency of H2-blending in a natural gas pipeline network. The conclusion of the paper is: the energy transmission capacity and the efficiency decrease with the introduction of H2, nevertheless, the authors conclude that it is not an obstacle, but the way of using transmission natural gas networks should be closely studied to find an economic optimum, based both on capital and operating expenses. To establish the comparison, the paper did not take into account the limits of the equipment; all equipment was considered as compatible with any load of hydrogen blending. In the current paper, the idea is to consider the hypothesis that the only factor which has impact on the infrastructure is the partial pressure of H2. The idea is not new, in 1802, Dalton published a law called Dalton’s Law of Partial Pressures [5]. Dalton established empirically that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual component gases. The partial pressure is the pressure that each gas would exert when it alone occupied the volume of the mixture at the same temperature. Independent of the limits of the equipment, the authors explore the relationships between a network capacity and its associated pressures in regards to the H2 partial pressure. Within the partial pressure constraint, the goal is to find the maximum H2 flowrate. This flowrate is then compared with a flowrate which is a function of % H2. Nevertheless, steel is subjected to hydrogen invasion while being exposed to hydrogen containing environments during mechanical loading: resulting in hydrogen embrittlement (HE). HE also depends on the textured microstructure. In the final results [6] [7], the measured fatigue data reveals that the fatigue life of steel pipeline is degraded by the added hydrogen. The H2 has an effect on the steel fatigue which is not simply due to the partial pressure. The idea of the authors through the results of their 2 papers is to give the key points to help to find the optimum points for introducing H2 into a natural gas network, because, for them, the idea is that partial pressure is a factor in the equilibrium between H2 capacity and the remaining lifetime of the equipment. This paper shows the interest of the pressure management. With this management, it is possible to reach a constant H2 injection flow independently of the natural gas flow in the pipeline. In conclusion, to optimize the H2 capacity in their current network, a proposal to the TSOs is to adjust their dispatching methodology and their Pipeline Integrity Management (PIM) [8] [9].

scholarly journals MOLECULAR HYDROGEN GENERATOR GVCH LIFE

2021 ◽  
pp. 65-68
Author(s):  
Volodymyr Moseichuk ◽  
Vladyslav Moseichuk ◽  
Vasyl Makolinets
Keyword(s):  
Musculoskeletal System ◽  
Molecular Hydrogen ◽  
Water Concentration ◽  
Hydrogen Gas ◽  
The Body ◽  
Water Volume ◽  
Antioxidant Systems ◽  
Pure Hydrogen ◽  
Hydrogen Generator ◽  
Hydrogen Water

Molecular hydrogen is one of the effective antioxidants, which not only does not disrupt normal metabolism in the body, but also activates its antioxidant systems. Hydrogen-saturated water has  antioxidant, anti-inflammatory, anti-allergic, anti-apoptotic properties, stimulates energy metabolism and contributes to the systemic recovery of the body. It is used as a therapeutic factor for the treatment of patients with various pathologies: arterial hypertension, coronary heart disease, diabetes, obesity, metabolic disorders, disorders of the musculoskeletal system. The article discusses the various methods of obtaining molecular hydrogen and hydrogen water (direct and indirect saturation). Technical characteristics are described and features of the hydrogen generator GVCh Life (manufacturer LTD «Chemtest Ukraine+», Kharkiv, Ukraine), which produces molecular hydrogen (purity of which is 99.99 %, productivity — 100 ml/min) and saturates water with it (https://chemtest.com.ua/generator_vodorodnoy_vodi_i_dihanie_gvch_life). In contrast to the problems of most known generators in the device GVChLife is completely no contact of the electrodes with water, so it is not subject to electrolysis and is not saturated with metal ions. Water saturated in this way has the following characteristics: redox potential 560 mV, hydrogen concentration 1.0–1.15 ppm(water volume 1 l, saturation duration 10 min). The generator can be used for both hydrogen saturation and hydrogen inhalation. In the case of therapeutic use of hydrogen water to obtain it, you can use any drinking water (spring, prepared or non-carbonated bottled), hydrogen inhalation using nasal cannulas. Inhalation of pure hydrogen gas (99.99 %) for 30 minutes is equal to the use of 15 liters of hydrogen water (concentration 1.1–1.2 ppm). Conclusions. The developed MoHC Life molecular hydrogen generator is safe to use, without special requirements during operation. It can be successfully used in the complex therapy of patients with various diseases, including musculoskeletal system.

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