现场总线技术在海洋石化工业中的应用

海南中海石油化学有限公司大化肥项目净水厂装置以Smar公司的基金会现场总线(FF)控制系统为主要采集与控制部件,完成对现场压力、流量、液位等物理量的精确采集与控制,并且把需要进行联锁控制的数字量或开关量直接传送至可编程序控制器LC700进行联锁控制,完成了整个水处理和供水的自动控制。该套现场总线控制系统既减轻了操作人员的劳动强度,又方便了设备维护,并且节省了大部分投资与设备维护费用。

基于层次分析法的沿海大型石化项目海洋减灾能力评价

文章针对沿海大型石化项目和海洋灾害特点,以工程自身防护能力、公司预警报能力和公司响应应急能力为准则层,筛选18项指标建立沿海大型石化项目海洋减灾能力评价体系,运用层次分析法构建沿海大型石化项目海洋减灾能力评价指标层次结构模型。结果显示,影响沿海大型石化项目海洋减灾能力的准则层权重由大到小依次为工程自身防护能力、公司预警报能力和公司响应应急能力。从各评价指标权重看,海堤高程和海堤完好程度是工程自身防护能力的主要影响指标;重大危险源监控覆盖率和主体防护工程定期检查频次是公司预警报能力的主要影响指标;应急设备保障率和应急物资储备度是公司响应应急能力的主要影响指标。以惠州炼化项目为例对其海洋减灾能力进行评价,应用该方法的评价结果比较客观可行,与项目现状比较吻合,可以为其海洋减灾能力建设提供指导。

Turbulence and Fossil Turbulence in Oceans and Lakes

Turbulence is defined as an eddy-like state of fluid motion where the inertial-vortex forces of the eddies are larger than any of the other forces that tend to damp the eddies out. Energy cascades of irrotational flows from large scales to small are non-turbulent, even if they supply energy to turbulence. Turbulent flows are rotational and cascade from small scales to large, with feedback. Viscous forces limit the smallest turbulent eddy size to the Kolmogorov scale. In stratified fluids, buoyancy forces limit large vertical overturns to the Ozmidov scale and convert the largest turbulent eddies into a unique class of saturated, non-propagating, internal waves, termed fossil-vorticity-turbulence. These waves have the same energy but different properties and spectral forms than the original turbulence patch. The Gibson (1980, 1986) theory of fossil turbulence applies universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as its growth is constrained and fossilized by buoyancy forces. Quantitative hydrodynamic-phase-diagrams (HPDs) from the theory are used to classify microstructure patches according to their hydrodynamic states. When analyzed in HPD space, previously published oceanic datasets showed their dominant microstructure patches are fossilized at large scales in all layers. Laboratory and field measurements suggested phytoplankton species with different swimming abilities adjust their growth strategies by pattern recognition of turbulence-fossil-turbulence dissipation and persistence times that predict survival-relevant surface layer sea changes. New data collected near a Honolulu waste-water outfall showed the small-to-large evolution of oceanic turbulence microstructure from active to fossil states, and revealed the ability of fossil-density-turbulence patches to absorb, and vertically radiate, internal wave energy, information, and enhanced turbulent-mixing-rates toward the sea surface so that the submerged waste-field could be detected from a space satellite (Bondur and Filatov, 2003).

Fossil biotas from Pakistan with focus on dinosaur distributions and discussion on paleobiogeographic evolution of Indo-Pak Peninsula

Recent geological and paleontological exploration in the Indus basin of Pakistan allowed the discoveries of numerous remains of non-marine reptiles( titanosaurian sauropod,abelisaurian and noasaurian theropod dinosaurs),and marine reptiles( crocodiles),flying reptiles( pterosaurs),marine and non-marine mammals,fishes,invertebrates,and plants,especially Pakistan is relatively rich in footprints / trackways in the Mesozoic.These vertebrates of Indo-Pakistan are very significant for paleobiogeographic study due to the present-day connection of this continent with Asia in Northern Hemisphere,whereas during past( Jurassic and pre-Jurassic) it was connected to the Gondwana. The Mesozoic vertebrates show close affinities with Gondwanan landmasses.The Cenozoic vertebrates show Eurasian affinity and migrated from Indo-Pak subcontinent to Eurasia or vice versa via Paleo Indus River systems along Western Indus Suture,after long journey of about 6 000 km the first collision of Indo-Pak subcontinent with Asia occurred at terminal Cretaceous.

Pollution Condition of Petroleum Hydrocarbon Pollutant and Estimation of Its Environmental Capacities in Summer in the Bohai Sea

The pollution condition of petroleum hydrocarbon (PH) was summarized in the Bohai Sea in this paper. The results showed that the mean concentration of PH was (25.7±13.6) mg/m3, varying from 4.4 to 64.8 mg/m3 in the survey sea area. Laizhou Bay and Bohai Bay have been contaminated badly inshore. The dynamic model for distribution of marine PH among multiphase environments in the Bohai Sea has been established. The environmental capacities (ECO) and surplus environmental capacities (SECO) of PH have been estimated in the Bohai Sea according to the dynamic model. The results showed that the ECo separately were about 29 169 t/a, 177 306 t/a and 298 446 t/a under the first, second and third, fourth class seawater quality standards requirement. And the ECO of Bohai Bay, Liaodong Bay, Laizhou Bay and Central Bohai Sea were about 5 255 t/a, 8 869 t/a, 4889 t/a and 10 156 t/a respectively under the first and second class seawater quality standards requirement.

Calculation of Environmental Capacity of Petroleum Hydrocarbon in Jiaozhou Bay

The method has been established to calculate the environmental capacity (ECO), surplus environment capacity (SECO) of water with respect to marine petroleum hydrocarbons associated with oil (PHAOs) and the self-purification capacity (SPCO) of main self-purification process to PHAOs in the Jiaozhou Bay, China, according to the dynamic model for distribution of marine PHAOs among multiphase environments. The variation of concentration of PHAOs in the Jiaozhou Bay is well simulated by the dynamic model. Based on the model, the ECo, SECo of water with respect to PHAOs in the Jiaozhou Bay were calculated during the last 10 years under the first-class and second-class quality standard requirement, according to SPCO of main self-purification process to PHAOs. The results show that about 200 tons of PHAOs could be discharged into the Jiaozhou Bay for maintaining the first class seawater quality standard, and about 600 tons of PHAOs for the second class seawater quality standard later.

Marine Renewable Energy Seascape

Energy production based on fossil fuel reserves is largely responsible for carbon emissions, and hence global warming. The planet needs concerted action to reduce fossil fuel usage and to implement carbon mitigation measures. Ocean energy has huge potential, but there are major interdisciplinary problems to be overcome regarding technology, cost reduction, investment, environmental impact, governance, and so forth. This article briefly reviews ocean energy production from offshore wind, tidal stream, ocean current, tidal range, wave, thermal, salinity gradients, and biomass sources. Future areas of research and development are outlined that could make exploitation of the marine renewable energy （MRE） seascape a viable proposition; these areas include energy storage, advanced materials, robotics, and informatics. The article concludes with a sustainability perspective on the MRE seascape encompassing ethics, leg- islation, the regulatory environment, governance and consenting, economic, social, and environmental constraints. A new generation of engineers is needed with the ingenuity and spirit of adventure to meet the global challenge posed by MRE.

Impacts of Seasonal Fossil and Ocean Emissions on the Seasonal Cycle of Atmospheric CO_2

The seasonal cycle of atmospheric CO2 at surface observation stations in the northern hemisphere is driven primarily by net ecosystem production (NEP) fluxes from terrestrial ecosystems. In addition to NEP from terrestrial ecosystems, surface fluxes from fossil fuel combustion and ocean exchange also contribute to the seasonal cycle of atmospheric CO2. Here the authors use the Goddard Earth Observing System-Chemistry (GEOS-Chem) model (version 8-02-01), with modifications, to assess the impact of these fluxes on the seasonal cycle of atmospheric CO2 in 2005. Modifications include monthly fossil and ocean emission inventories. CO2 simulations with monthly varying and annual emission inventories were carried out separately. The sources and sinks of monthly averaged net surface flux are different from those of annual emission inventories for every month. Results indicate that changes in monthly averaged net surface flux have a greater impact on the average concentration of atmospheric CO2 in the northern hemisphere than on the average concentration for latitudes 30-90°S in July. The concentration values differ little between both emission inventories over the latitudinal range from the equator to 30°S in January and July. The accumulated impacts of the monthly averaged fossil and ocean emissions contribute to an increase of the total global monthly average of CO2 from May to December.An apparent discrepancy for global average CO2 concentration between model results and observation was because the observation stations were not sufficiently representative. More accurate values for monthly varying net surface flux will be necessary in future to run the CO2 simulation.

海洋石油化工装置配管质量控制的关键问题及措施探讨

随着我国海洋石油开采事业的发展,对于海洋石油化工装饰配管施工技术也提出了更高的要求。海洋石油化工配管需要在充分重视环境污染和施工安全的基础上,结合施工专业技术和经验,优化施工质量,提升施工品质。本文针对海洋石油化工装置配管质量控制的几个关键问题进行探讨,并提出了相应的解决对策。