油田高温计量接转站工艺技术

随着蒸汽辅助重力泄油经过先导试验后进入工业化推广阶段,现有地面工艺难以满足油井高温产出液的需要。为解决这一问题,提出了建立高温计量接转站的生产工艺要求,确定了蒸汽辅助重力泄油生产中采用高温集油、高温计量、高温输送的技术思路,其中高温缓冲罐、高温计量和高温外输泵是此项工艺实现的关键技术。在没有经验可供借鉴的条件下,通过大量的理论研究与现场试验,成功地解决了高温输油泵、油气分离缓冲罐、液面检测仪、自动控制系统等技术难题,为工业化应用奠定了技术基础。

SAGD高温集输工艺技术研究与应用

超稠油蒸汽辅助重力泄油(Steam Assisted Gravity Drainage简称SAGD)开采技术是蒸汽吞吐开采工艺有效的接替方案,辽河油田SAGD开发经历了为期3年的先导试验,2006年起进入工业化应用阶段。全新的采油工艺为地面工程建设提出了全新的课题和严峻挑战,本文在高温输油先导试验的基础上,研究了高温输油设备、密闭耐高温油气分离缓冲罐、密闭缓冲罐液位计、自动控制系统、在线高温取样器以及高温在线计量技术,为SAGD工业化应用提供了有效的技术支持。

基于双光梳光谱技术的气体温度测量研究

双光梳光谱作为一项新兴技术,具备响应快、分辨率高、灵敏度高、光谱范围宽等优点,在分子精密光谱分析领域中有独特的优势和广阔的发展前景。提出了一种基于双光梳光谱的高温气体测量方案,利用两个存在微小重频差的光梳通过异步采样实现高温气体吸收光谱的高精度测量,并利用光谱-温度反演算法得到气体温度值。试验中采用了重复频率约为205.315 MHz和205.365 MHZ的双光梳系统,实现了1 057 K温度下CO_(2)气体在4.2μm波长附近吸收光谱的高精度测量。结果表明,该技术作为一种主动式测温技术,具备高温气体的准确测量能力,在国防军工装备高温计量测试领域有重要的应用前景。

New Colorimetric Pyrometer with Optical Fiber Link

Based on the concept of thermo-radiation theory,the principle of non-contact temperature measurement with optical fiber is introduced.The new pyrometer operates on the basis of two-way temperature signal division calculation via microcomputer signal processing system.Its design method and smart construction of the electro-optical system possess such advantages as high measurement accuracy,freedom from electric interference and other perturbations as well as flexible applications.The indication scale of the measured temperature and experiment results are given in this paper.

A General Thermal Equilibrium Discharge Flow Model

Based on isentropic flow and thermal equilibrium assumptions, a model was derived to calculate discharge flow rate, which unified the rules of room temperature water discharge, high temperature and high pressure water discharge, two-phase critical flow, saturated steam and superheated steam critical flow, and gave a method to calculate critical condition. Because of the influence of friction, the entropy is increased in the actual discharge process, and the discharge flow rate in thermal equilibrium condition can be obtained by the original model multiplied by an appropriate correction coefficient. The model calculated results agreed well with the experiment data of long nozzle critical flow.

The definition analyses of radiation temperature measurement area

In the research of primary spectrum pyrometry, this paper discussed the definition problem of radiation temperature measurement area based on the measurement coordinates. For the linear spectrum emissivity model and improved monotonic spectrum emissivity model, the characteristics of radiation temperature measurement area restricted by the measurement coordinates were theoretically analyzed, through the investigations of the temperature and emissivity coordinate axes. Choosing the specific primary spectrum pyrometer as an example in applications, the theoretical area of radiation temperature measurement of this pyrometer was given and it was verified through blackbody experiments. The discussions of this paper will provide the necessary foundation for the theory research development of primary spectrum pyrometry and the realization of technical applications.

Response of Plant Community Carbon and Nitrogen Stoichiometry to Experimental Warming on the Qinghai-Tibet Plateau

Low temperature is an important limiting factor for alpine ecosystems on the Tibetan Plateau. This study is based on data from on-site experimental warming platforms(open top chambers, OTC) at three elevations(4300 m, 4500 m, 4700 m) on the Qinghai-Tibet Plateau. The carbon and nitrogen stoichiometry characteristics of plant communities, both above-ground and below-ground, were observed in three alpine meadow ecosystems in August and September of 2011 and August of 2012. Experimental warming significantly increased above-ground nitrogen content by 21.4% in September 2011 at 4500 m, and reduced above-ground carbon content by 3.9% in August 2012 at 4300 m. Experimental warming significantly increased below-ground carbon content by 5.5% in August 2011 at 4500 m, and the below-ground ratio of carbon to nitrogen by 28.0% in September 2011 at 4300 m, but reduced below-ground nitrogen content by 15.7% in September 2011 at 4700 m, below-ground carbon content by 34.3% in August 2012 at 4700 m, and the below-ground ratio of carbon to nitrogen by 37.9% in August 2012 at 4700 m. Experimental warming had no significant effect on the characteristics of community carbon and nitrogen stoichiometry under other conditions. Therefore, experimental warming had inconsistent effects on the carbon and nitrogen stoichiometry of plant communities at different elevations and during different months. Soil ammonium nitrogen and nitrate nitrogen content were the main factors affecting plant community carbon and nitrogen stoichiometry.

Experimental warming shifts coupling of carbon and nitrogen cycles in an alpine meadow

Aims Terrestrial ecosystem carbon(C)uptake is remarkably regulated by nitrogen(N)availability in the soil.However,the coupling of C and N cycles,as reflected by C:N ratios in different components,has not been well explored in response to climate change.Methods Here,we applied a data assimilation approach to assimilate 14 datasets collected from a warming experiment in an alpine meadow in China into a grassland ecosystem model.We attempted to evaluate how experimental warming affects C and N coupling as indicated by constrained parameters under ambient and warming treatments separately.Important Findings The results showed that warming increased soil N availability with decreased C:N ratio in soil labile C pool,leading to an increase in N uptake by plants.Nonetheless,C input to leaf increased more than N,leading to an increase and a decrease in the C:N ratio in leaf and root,respectively.Litter C:N ratio was decreased due to the increased N immobilization under high soil N availability or warming-accelerated decomposition of litter mass.Warming also increased C:N ratio of slow soil organic matter pool,suggesting a greater soil C sequestration potential.As most models usually use a fixed C:N ratio across different environments,the divergent shifts of C:N ratios under climate warming detected in this study could provide a useful benchmark for model parameterization and benefit models to predict C-N coupled responses to future climate change.