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[Objective] The maximum operating pressure for underground gas storage facilities designed for oil and gas reservoirs, both constructed and under construction in China, is currently set at the original formation pressure. There have yet to be successful cases of overpressure operation, which significantly impacts the economic benefits of converting depleted oil and gas reservoirs into underground gas storage facilities. This article aims to evaluate the maximum operating pressure and storage capacity of the Nanpu 1-29 gas storage facility from the perspective of the ultimate bearing capacity of cap layers and faults, with the goal of effectively enhancing the construction benefits of the facility. [Methods] The evaluation of the maximum operating pressure for the Nanpu 1-29 gas storage facility in eastern Hebei is based on the minimum principal stress measured in situ in the mining wells. Different effective porosity calculation methods are employed to quantitatively evaluate the effective storage capacity of gas and oil reservoirs, as well as the incremental capacity after pressure boosting operation, based on their development differences. [Results] The evaluation of the maximum operating pressure for the Nanpu 1-29 gas storage facility indicates that the minimum principal stress of the cap layers determined by the in-situ measurements in the mining wells is 34.00 MPa. Based on the tensile failure criteria determined by the minimum principal stress, the maximum operating pressure for the tensile failure of the cap layer is 27.20 MPa. Combined with the maximum safe injection pressure corresponding to shear failure of the cap layer (30.60 MPa) and the maximum safe injection pressure corresponding to unstable slip of the fault (27.60 MPa), the final maximum operating pressure for the Nanpu 1-29 gas storage facility is determined to be 27.20 MPa. Based on the effective storage capacity calculation model, considering factors such as the water content of the gas reservoir, residual water and edge porosity as well as the coefficient of influence, the efficiency of gas-driven fluid, and the utilization rate of oil-containing space, the maximum operating pressure increased from the original formation pressure of 22.50 MPa to 27.20 MPa. The practical storage capacity of the gas storage facility increased from 15.46x108 m³ to 18.14x108 m³, an increase of approximately 17.3%. [Conclusion] (1) The construction of gas storage facilities can be re-evaluated for the maximum operating pressure based on the minimum principal stress measured in situ in the mining wells, and overpressure design can be conducted under appropriate conditions. (2) Overpressure design can effectively increase storage capacity and improve the economic benefits of reservoir construction. [Significance] The research results have a certain reference value for the quantitative evaluation of the maximum operating pressure and storage capacity of other underground gas storage facilities, and are expected to significantly improve the economic benefits of overpressure-designed reservoir-type gas storage facilities in China. [ABSTRACT FROM AUTHOR]

To solve the problem of the equation structure becoming more complex in the improved soil conservation service curve number (SCS- CN) model, a SCS- CN model with revised effective precipitation ( SCS- CN- REP) is proposed by introducing a revised coefficient after a comparison between the standard SCS-CN model and the improved model. Furthermore, for the complex area with low impact development (LID) in a city, a distributed SCS-CN-REP model was developed based on a hydrological response unit division in which the effects of the LID facility′s storage capacity on rainfall-runoff are also considered. Finally, taking the Shuangzi residential district in Beijing City as a study area, the rainfall-runoff is simulated and compared using the distributed SCS-CN-REP model. An analysis of the SCS- CN- REP model showed that when the revised coefficient is 1. 0, it is equivalent to the standard model, when the revised coefficient is smaller than 1. 0, it is equivalent to the improved model. In essence, the revised coefficient is a limit value of the runoff coefficient varied with the increase in precipitation. The distributed SCS-CNREP model application results demonstrated that the calculated runoff depth values are in good agreement with the measured values. The determination coefficients and Nash efficiency coefficient are 0. 91 and 0. 83 when the adopted value of the revised coefficient for permeable surfaces is 1. 0, and are 0. 92 and 0. 91 when the adopted value is less than 1. 0. The effects of the latter model are better than the former, indicating that the simulation effect can be effectively improved when the adopted value of the revised coefficient for permeable surfaces is less than 1. 0 in the distributed SCS-CN-REP model. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A series of true triaxial compression tests on sandstone were carried out based on the true triaxial testing machine. The sandstone samples were taken from a gas storage facility， with a buried depth of 3600 meters. The strength and deformation characteristics of deep sandstone under true triaxial stress were studied， and the elastic modulus， cohesion， friction angle and peak failure strength of deep sandstone and shallow sandstone were compared. The results show that with the increase of the intermediate principal stress， the peak strength of the deep sandstone will also increase， the crack initiation stress and the damage stress of the deep sandstone will also increase， and the intermediate principal strain at the peak will decrease. With the increase of sandstone depth， the elastic modulus， cohesion and friction angle of sandstone all show an increasing trend. The octahedral shear stress of the peak failure strength of the shallow rock and the effective mean normal stress show a nonlinear relationship， while the octahedral shear stress of the peak failure strength of the deep rock has a linear relationship with the effective mean normal stress. And the Mogi-Coulomb criterion is more suitable for reflecting the strength characteristics of deep sandstone at failure. [ABSTRACT FROM AUTHOR]

A series of true triaxial compression tests on sandstone were carried out based on the true triaxial testing machine. The sandstone samples were taken from a gas storage facility， with a buried depth of 3600 meters. The strength and deformation characteristics of deep sandstone under true triaxial stress were studied， and the elastic modulus， cohesion， friction angle and peak failure strength of deep sandstone and shallow sandstone were compared. The results show that with the increase of the intermediate principal stress， the peak strength of the deep sandstone will also increase， the crack initiation stress and the damage stress of the deep sandstone will also increase， and the intermediate principal strain at the peak will decrease. With the increase of sandstone depth， the elastic modulus， cohesion and friction angle of sandstone all show an increasing trend. The octahedral shear stress of the peak failure strength of the shallow rock and the effective mean normal stress show a nonlinear relationship， while the octahedral shear stress of the peak failure strength of the deep rock has a linear relationship with the effective mean normal stress. And the Mogi-Coulomb criterion is more suitable for reflecting the strength characteristics of deep sandstone at failure. [ABSTRACT FROM AUTHOR]

According to the current codes and specifications, the calculated value of the storm runoff for storage yards in coal and ore terminals is directly related to the minimum value of annual maximum daily rainfall depth. But, this value is small, which is likely to cause dusty rainwater to overflow into the sea. In this paper, through statistical analysis of the rainfall data of 15 typical port areas, the reasonable rainfall value for the calculation of the storm runoff of storage yard is discussed. The results show that the average value of annual maximum daily rainfall depth can better reflect the local annual comprehensive rainfall characteristics. It will not cause a significant increase in the scale of rainwater storage facilities, but can greatly reduce the probability of rainwater overflow in storage yard. Therefore, it is recommended to take the average value of annual maximum daily rainfall depth as the rainfall value for the calculation of the storm runoff for storage yards. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Automatic detection of granary storage quantity with fast speed and high accuracy is an important technology for national food security. In this paper, according to the characteristics of grain peaks in different granary type (flat warehouse, squat silo and vertical silo), the mathematical relationship between granary storage quantity and the bottom/side pressure of granaries is established, a new on line model for the grain storage quantity measurement is also proposed. For the given grain and storage type, the storage quantity is only related to the bottom pressure and side pressure on the granary and the grain height in the granary, which make it possible to measure the storage quantity by pressure sensors, as long as the above pressure value and grain height is determined, the storage quantity can be obtained with high accuracy. Accord to the measurement requirement on the accuracy and robustness on the grain storage quantity, the pressure sensors are put with the shape of two circles, each circle includes multiple pressure sensors. This is because the inhomogeneous and randomness of the pressure value on the bottom and side of the granary. Therefore, more sensors can detect the pressure value on the bottom and side with high accuracy. However, the more pressure sensor used, the higher on the cost of the measurement system. Based on the tradeoff on the cost and accuracy, the two circles setup is proposed to measure the pressure value with high accuracy. The inner circle which is far from the side wall provides the pressure value on the granary bottom and the outer circle which is close to the side wall provides the pressure value on the granary side. In this method, the two circles setup not only eliminated the inhomogeneous and randomness of the granary pressure value measurement, but also reduced the number of the required pressure sensors. With the pressure values obtained, according to the principle model of the storage quantity measurement, this paper proposed a new model based on polynomial expansion to measure the storage quantity. The model use the polynomial of the average value on the inner pressure sensors to estimate the bottom pressure value, and use the polynomial of the average value on the outer pressure sensors to estimate the side pressure value, and obtain the grain height based on the above two polynomial. The proposed model can obtain the polynomial coefficient and order based on the sample of the pressure values automatically, which provides the high accuracy on the grain storage quantity measurement based on the pressure sensors. At the same time, the granary type such as granary shape and size are also introduced in the model, which improved practicality for different types of the granary of the proposed model. Real Practical storage quantity detection results show that the detection error of the proposed model is less than the requirement 2.5%, and the cost is reduced significantly, which demonstrates that the proposed granary storage quantity detection model is effective and well meet the demand of national granary storage quantity detection. [ABSTRACT FROM AUTHOR]

A real-time monitoring system of dangerous goods in storage environment is developed. The new system can collect, send and analyze the related environmental data, realize the early warning and report to the monitoring center. According to the characteristics of dangerous goods, the system uses sensing technology to achieve real-time acquisition; and aggregate environmental data to the main module with GPRS wireless transmission function on site by the LIN field bus network. The main module on site uses the GPRS network to transmit the data to the monitoring center of the host computer through by the wireless ways. The environment parameter data are processed, displayed and stored by the PC application program. With the application of the new system, the on duty staff in monitoring center can look up the dynamic data of the storage of dangerous goods in order to prevent accidents. The system is of great significance for the safeguard of dangerous goods storage security. [ABSTRACT FROM AUTHOR]

Urban logistics storage facilities have the nature of network based on commercial trend and demand. In this paper, we first analyze the necessity and feasibility to change the independent decision- making model into interact decision-making model from the perspective of the value stream. Then, we establish a network equilibrium model with the competition of the multi-level members of the supply chain logistics which include the logistics storage facilities and the supplier or demander of the commodity using the variational inequalities theory. Besides, we also get conditions which can make the system reach equilibrium and offer the economic interpretation and the solving algorithm. Finally, we validate th model and present its decision-making applications by solving the specific examples. It shows that storage facilities layer and layer of the commodity's supply and demand always influence and restrict each other, and the improvement of the facilities efficiency, the migration of the sites and other behaviors like these may lead to the regular change of the market pattern, the quantities of commodity, the prices and the social welfare. [ABSTRACT FROM AUTHOR]