Oil outflow estimates for tankers and barges

Results of an analysis to estimate potential oil outflow from tankers in the event of groundings and collisions is presented. Three baseline tanker types are considered: pre-MARPOL (COW), MARPOL '73 (SBT only), MARPOL '73/'78 (PL/SBT) before and after these tankers have been retrofitted with various combinations of pollution prevention measures. Specifically the analysis examines four tanker sizes, 46 600, 71 000, 152 000 and 268 000 dwt, and various pollution measures — protectively located spaces (PL/spaces) in various ballast arrangements and with clean ballast tanks (CBTs), hydrostatically balanced loading (HBL), probabilistically located HBL, combinations of HBL and PL/spaces, double bottom or double side retrofits, and replacement of the tanker with a double hull vessel. Additionally, oil outflow estimates are presented for a US coastal and an ocean going barge of over 5000 gt with and without PL/spaces, PL/SBT, and HBL. The accidental oil outflow estimates are developed in accordance with probabilistic and deterministic models of IMOs MARPOL Annex I Regulations 13F and 13G. The accidental oil outflow estimates presented in the paper may provide oil spill response and related organizations with information to assist in planning for oil spill response activities.     

Pure oxygen-enhanced biodegradation for contaminated groundwater

On-site oxygen generation was chosen as the most effective and efficient source of pure oxygen for enhancing biodegradation at a hydrocarbon-contaminated oil and gas well site in northern Michigan. Contaminants include benzene, toluene, ethylbenzene, and xylenes released through natural gas dehydration practices that were halted in 1985. Free product and contaminated soil were completely removed from the source area in spring 1989, leaving only the groundwater plume for further remediation. This article discusses the project's two phases—a purge and treat system and the pure-oxygen bioremediation system—each costing $75,000. It also details the combined system's technical elements (including purge and monitoring wells, oxygen generator, and drainfield), and cleanup results (including how pure oxygen has helped destroy contaminants, not merely move them to other media).     

A study on the effects of oil fires on fire booms employed during the in situ burning of oil

For over 10 years scientists have studied the effects of in situ burning of oil on air and water quality and potential related health issues. The recent Newfoundland Offshore Burn experiment, conducted by Environment Canada, was the culmination of several years of work. The results of this experiment found that ‘emissions from the in situ oil fire were lower than expected and all compounds and parameters measured were below health concerns at 150 m from the fire’ (The Newfoundland Offshore Burn Experiment—NOBE, Preliminary Results of Emissions Measurement). Polyaromatic Hydrocarbons (PAHs) were found to be lower in the soot generated from the fire than in the starting oil prior to the fire. The conclusion reached was that the environmental benefits resulting from the burning of oil spills far outweigh the potential air pollution caused from the smoke. These findings now open the door on the use of in situ burning of oil as a major tool to be used to mitigate environmental damage from oil spills.As a result of these and other test findings, Region 6 of the Regional Response Team (made up of the U.S. Coast Guard, The Minerals Management Service, The Department of Environmental Quality, The U.S. Environmental Protection Agency, and other state and federal agencies) had pre-approved the use of in situ burning of oil spills for offshore Louisiana and Texas. Other parts of the country and other countries are evaluating the use of in situ burning to combat oil spills. Now that the scientific community has weighed the environmental costs and benefits of in situ burning it is time to address the operational and procedural issues.     

Hydrogen peroxide for physicochemically degrading petroleum-contaminated soils

Catalyzed hydrogen peroxide was applied to contaminated soil at an equipment storage yard in Reno, Nevada, that had also been used as a dump for motor oil and diesel fuel for twenty years. The site is only a quarter mile from the Truckee River—a principal source of Reno's drinking water. This article details hydrogen peroxide's advantages, disadvantages, costs, and treatment for reducing to below the 100 mg/kg Nevada action level the petroleum hydrocarbons in the yard's arid soil, which is characterized by low organic carbon content and low manganese oxide content.     

Recovery of benzene-rich oil from the degradation of metal- and metal oxide-containing poly(ethylene terephthalate) composites

Pure poly(ethylene terephthalate) (PET) resin and metal-/metal oxide-containing PET composites were thermally decomposed in the presence of Ca(OH)₂ using a tube reactor. The effects of batch and continuous processing, the presence of Ca(OH)₂, and PET size on benzene production were investigated. A maximum benzene yield and purity of 82.9 % and 78.8 wt%, respectively, were obtained at 700 °C in the presence of Ca(OH)₂ when using small PET particles; further, a continuous feed reactor was favored over a batch reactor. Effective contact between PET and Ca(OH)₂ was important in the PET degradation, which promoted hydrolysis of PET and decarboxylation of terephthalic acid, whereas pyrolysis was suppressed. Furthermore, the results of thermal decomposition of PET-based waste—PET-based X-ray films, magnetic tape, and prepaid cards—indicated that the metal and metal oxides contained in the waste had no significant catalytic effect on PET degradation or on the recovery of benzene-rich oil in the presence of Ca(OH)₂.     

活性碳纤维电极-生物膜反应器对废水的强化脱氮性能

利用自制的活性碳纤维电极-生物膜反应器对低碳氮比(碳元素与氮元素的质量比)废水进行了脱氮实验.实验结果表明:当进水COD和碳氮比较低时,碳氮比和电流密度均对反应器的脱氮性能有很大影响;当碳氮比小于3.0时,出水的ρ(NO3--N)随进水碳氮比的增大而减小;当进水COD为70 mg/L,ρ( NO3--N)为35 mg/L、碳氮比为2.0、电流密度为0.025 mA/cm2、反应时间为8h时,出水的ρ(NO3--N)达到最低值11.2 mg/L,NO3--N去除率为68.0％.在适宜的碳氮比条件下,电极-生物膜反应器具有显著的强化脱氮作用,其对NO3--N的去除率与单纯生物膜反应器相比可提高6.0～15.0个百分点.保持碳氮比不变,提高进水COD会导致所需电流密度的提高和脱氮能力的下降.     

考虑油滴碰撞聚结的斜板除油过程模拟

考虑离散油滴在油田废水除油过程中发生的油滴碰撞聚结现象,模拟得出斜板除油器内全部油滴的动态信息,用于斜板除油器除油效率的计算.对矩形同向流斜板除油过程的模拟研究表明:油滴的碰撞聚结会增加斜板除油的效率;当废水的原始含油浓度增大时,斜板除油的效率会增大,碰撞聚结对除油效率提高的影响也越大;废水流动速度提高及斜板的倾斜角度增加均会使斜板的除油效率降低,但此时油滴碰撞聚结对除油效率的影响仍很明显.     

Lead Speciation in the Sediments of the Heavily Polluted Western Harbor of Alexandria

The Western Harbor (WH) became under stress in the past decades, following successive increase in population. This study deals with local distribution of total lead and its species in the WH sediments. The lead content was high and there was a relationship between its enrichment and oil dispersed from ships. The lowest total lead value was found in the harbor middle far from direct effects of pollution. A five-step sequential extraction scheme was applied to illustrate the contribution shared by each individual fraction in the total lead concentration in the WH sediments. The exchangeable fraction (F1) was very low. The bound to carbonate fraction (F2), the bound to iron-manganese oxide fraction (F3) and the bound to organic matter—sulfide fraction (F4) ranked fourth, second and third in abundance. Oxygen was the main factor controlling the value of F2. F3 gave a direct relationship with total lead. The high levels of F4 occurred at locations of low salinity and enriched with organic matter. The residual fraction (F5) dominated other lead species, reflecting the sediment composition and the amounts of discharged pollutants.     

The Oil Pollution Act of 1990: A Decade Later

Analysis of oil spills data confirms that accidental oil spills are natural phenomenon and that there is a relationship between accidental oil spills and variables like vessel size, vessel type, time and region of spill. The volume of oil spilled bears relationship with the volume of petroleum imports and domestic movement of petroleum and proportion of large oil spills. Finally, navigational risk increases with increase in marine traffic and is also determined by variables like hydrographic and meteorological conditions, water configuration, maneuvering space, obstructions and nuisance vessels. The Oil Pollution Act, 1990 (OPA 90) was passed by the US Congress in the aftermath of 11 million gallon spill of crude oil in Prince William Sound, Alaska. The objective of OPA 90 was to minimize marine casualties and oil spills by addressing preventive, protective, deterrent and performance aspects of accidental oil spills. The arm of various regulations like double-hull tankers and vessel response plans extended to both US flagged and foreign-flagged tank vessels. The cost–benefit analysis of major regulations shows that the estimated costs exceed estimated benefits. We observe from USCG data on oil spills by size, by vessel type, Coast guard district and type of petroleum product that there have been significant reductions in the number and the quantity of oil spills. Our regression results show that the quantity of oil spilled increases with increase in oil imports but increases at a decreasing rate. The quantity of oil spilled decreases with increases in the domestic oil movements. Furthermore, percent of oil spills larger than 10,000 gallons also increases the potential quantity of oil spilled. OPA 90 has been a deterrent to accidental oil spills but the finding is not conclusive.     

Two granular-activated carbons for adsorbing army explosives

Explosives-contaminated groundwater percolating from storage ponds at the Milan Army Ammunition Plant (MAAP) in Milan, Tennessee, into the Claiborne aquifer threatens to contaminate more groundwater—and possibly surface water—in the area. The research described in this article sought to determine whether granular-activated carbon (GAC) could help remove the explosives from the water and to identify which carbons can adsorb the most TNT, RDX, HMX, Tetryl, and others. Two carbons—Atochem, Inc. GAC 830 and Calgon Filtrasorb 300—were found to be promising candidates. As for what to do with the explosives that would be adsorbed, as well as the contaminated carbon, stay tuned.     

溢油监测技术在石油石化企业环境风险防控中的应用

针对石油石化企业的溢油风险,提出企业在厂区雨水系统、外排口、涉水生产设施、环境敏感受体、溢油事故应急处置5类场景下的溢油监测需求,总结了溢油监测技术的类型和特点,介绍了可见光、红外、紫外、荧光、高光谱、微波辐射、雷达、电磁能量吸收等溢油监测技术的应用现状和优缺点。提出:企业溢油监测系统可分为企业内部溢油风险分级管控监测、企业边界的溢油风险报警监测、敏感环境监视的风险预警监测、溢油事故应急救援的溢油处置监测4个层次的运行模式。     

The technology windows-of-opportunity for marine oil spill response as related to oil weathering and operations

This paper identifies and estimates time periods as ‘windows-of-opportunity’ where specific response methods, technologies, equipment, or products are more effective in clean-up operations for several oils. These windows have been estimated utilizing oil weathering and technology performance data as tools to optimize effectiveness in marine oil spill response decision-making. The windows will also provide data for action or no-action alternatives. Crude oils and oil products differ greatly in physical and chemical properties, and these properties tend to change significantly during and after a spill with oil aging (weathering). Such properties have a direct bearing on oil recovery operations, influencing the selection of response methods and technologies applicable for clean up, including their effectiveness and capacity, which can influence the time and cost of operations and the effects on natural resources.The changes and variations in physical and chemical properties over time can be modeled using data from weathering studies of specific oils. When combined with performance data for various equipment and materials, tested over a range of weathering stages of oils, windows-of-opportunity can be estimated for spill response decision-making. Under experimental conditions discussed in this paper, windows-of-opportunity have been identified and estimated for four oils (for which data are available) under a given set of representative environmental conditions. These ‘generic’ windows have been delineated for the general categories of spill response namely: (1) dispersants, (2) in situ burning, (3) booms, (4) skimmers, (5) sorbents, and (6) oil-water separators. To estimate windows-of-opportunity for the above technologies (except booms), the IKU Oil Weathering Model was utilized to predict relationships—with 5 m s⁻¹ wind speed and seawater temperatures of 15°C.The window-of-opportunity for the dispersant (Corexit 9527^®) with Alaska North Slope (ANS) oil was estimated from laboratory data to be the first 26 h. A period of ‘reduced’ dispersibility, was estimated to last from 26–120 h. The oil was considered to be no longer dispersible if treated for the first time after 120 h. The most effective time window for dispersing Bonnic Light was 0–2 h, the time period of reduced dispersibility was 2–4 h, and after 4 h the oil was estimated to be no longer dispersible. These windows-of-opportunity are based on the most effective use of a dispersant estimated from laboratory dispersant effectiveness studies using fresh and weathered oils. Laboratory dispersant effectiveness data cannot be directly utilized to predict dispersant performance during spill response, however, laboratory results are of value for estimating viscosity and pour point limitations and for guiding the selection of an appropriate product during contingency planning and response. In addition, the window of opportunity for a dispersant may be lengthened if the dispersant contains an emulsion breaking agent or multiple applications of dispersant are utilized. Therefore, a long-term emulsion breaking effect may increase the effectiveness of a dispersant and lengthen the window-of-opportunity.The window-of-opportunity of in situ burning (based upon time required for an oil to form an emulsion with 50% water content) was estimated to be approximately 0–36 h for ANS oil and 0–1 h for Bonnie Light oil after being spilled. The estimation of windows-of-opportunity for offshore booms is constrained by the fact that many booms available on the market undergo submergence at speeds of less than 2 knots. The data suggest that booms with buoyancy to weight ratios less than 8:1 may submerge at speeds within the envelope in which they could be expected to operate. This submergence is an indication of poor wave conformance, caused by reduction of freeboard and reserve net buoyancy within the range of operation. The windows-of-opportunity for two selected skimming principles (disk and brush), were estimated using modeled oil viscosity data for BCF 17 and BCF 24 in combination with experimental performance data developed as a function of viscosity. These windows were estimated to be within 3–10 h (disk skimmer) and after 10 h (brush skimmer) for BCF 17. Whereas for BCF 24, it is within 2–3 d (disk skimmer) and after 3 d (brush skimmer).For sorbents, an upper viscosity limit for an effective and practical use has in studies been found to be approximately 15,000 cP, which is the viscosity range of some Bunker C oils. Using viscosity data for the relative heavy oils, BCF 17 and BCF 24 (API gravity 17 and 24), the time windows for a sorbent (polyamine flakes) was estimated to be 0–4 and 0–10 d, respectively. With BCF 24, the effectiveness of polyamine flakes, was reduced to 50% after 36 h, although it continued to adsorb for up to 10 d. For BCF 17, the effectiveness of polyamine flakes was reduced to 50% after 12 h, although it continued to adsorb for up to 4 d. The windows-of-opportunity for several centrifuged separators based upon the time period to close the density gap between weathered oils and seawater to less than 0.025 g ml⁻¹ (which is expected to be an end-point for effective use of centrifugal separation technology), were estimated to be 0–18 (ANS) and 0–24 h (Bonnie Light) after the spill. Utilizing the windows-of-opportunity concept, the combined information from a dynamic oil weathering model and a performance technology data base can become a decision-making tool; identifying and defining the windows of effectiveness of different response methods and equipment under given environmental conditions. Specific research and development needs are identified as related to further delineation of windows-of-opportunity.     

Enhanced oil biodegradation with mineral fine interaction

During recent oil spill clean-up operations, residual oils stranded in the intertidal environment were successfully dispersed into the sea by physically accelerating the natural interaction between oil and mineral fines. Oil-mineral fine interaction reduces the adhesion of oil to solid surfaces and promotes the formation of stable micron-sized oil droplets in the water column. By increasing the oil-in-water interface, i.e. the oil becomes more accessible to nutrients, oxygen and bacteria, this interaction becomes a key factor in enhancing oil biodegradation. There is, however, concern that this technique merely transports the oil from one compartment of the environment to another. In our study, controlled laboratory shaker-flask experiments showed that oil-mineral fine interactions stimulates microbial activity by enhancing both the rate and extent of oil degradation by stimulating microbial activity. These results support the application of shoreline oil spill clean-up techniques based on the acceleration of oil-mineral fine interactions.     

Hydroreforming over Ni/H-beta of the thermal cracking products of LDPE, HDPE and PP for fuel production

The thermal cracking at 400?°C of pure polyolefins—low density polyethylene (LDPE), high density polyethylene (HDPE) and polypropylene (PP) and a standard polyolefin mixture (46?% LDPE?+?27?% HDPE?+?28?% PP)—was studied together with the catalytic hydroreforming of the obtained oils over Ni/h-beta at 310?°C under 20?bar of hydrogen. The oils obtained after the thermal cracking of PP contain the highest amount of gasoline (58?%), while those coming from HDPE the lowest (39?%). The bromine index of the oils was very high, ranging from 54.1 (LDPE) to 83.8 (PP), indicating a high olefinic content of the oils. Additionally, the thermal cracking of the mixture indicates the occurrence of a synergestic effect among plastics, with transfer of methyl groups from PP to polyethylenes. Ni/h-beta (Si/Al?=?25; Ni content?=?6.2?wt%) catalyst was used in the hydroreforming since it contains a bimodal pore size distribution (0.6/3.1?nm), which improves accessibility of the oil molecules to the catalytic sites. After the hydroreforming and regardless of the plastics used, the share of lighter products (gasoline and gases) increases, reaching a remarkable 68?% of gasolines with the oils coming from PP. Regardless of the starting feed, the amount of useful fuels (gasoline?+?light diesel) was within 80–85?%. Additionally, the oils were successfully hydrogenated since the bromine indexes dropped below 7, indicating that more than 90?% of the starting olefins were saturated. The usage of catalysts increased the amount of aromatics in the obtained oils within 13–20?%, depending on the starting plastic. Likewise, the isoparaffin content of the gasolines was within 35–40?%, except for PP, where it was enhanced to 62?%. However, the research octane number (RON) of the gasolines from LDPE and PP and the cetane indexes of the diesel from all the plastics were promising for their application as fuels.     

水域泄漏油品回收处理技术

提出了水域泄漏油品回收技术的装备需求,介绍了水域泄漏油品问收处理措施.采用拦油栅来控制漂浮在水上的油品,将泄漏油品集中在相对较小的区域内,并使水面的浮油层加厚,然后使用人工或机械对泄漏油品进行回收.对于水域中的少量泄漏油品,采用吸油材料来进行吸附.在油膜较薄,难以用机械方法回收的情况下,使用消油剂或固化剂进行处理.水域...     

Using a composite material containing waste tire powder and polypropylene fiber cut end to recover spilled oil

The superior oil absorption capacity of recycled polypropylene (PP) fiber and waste tire powder were used to recover spilled engine oil. We used ASTM F726-99 method to evaluate oil adsorbing capability of PP fiber and found it to have a large, rapid oil sorption capacity. However, its lack of elasticity dramatically limited that capacity after repeated use. Tire powder, which absorbs less oil more slowly, is more elastic than PP fiber and can be used repeatedly up to a hundred times without losing its oil adsorption capability. We combined PP fiber and tire powder to develop a composite material capable of recovering greater amounts of oil than any of its components. This composite can be use repeatedly for at least 100 times. Thus, the material cost for recovering 1 ton of spilled oil is about USD $0.03, making it very competitive on the market.     

微生物降解重油的初步研究

丛石油污染的土壤中筛选出一株假单胞菌,考察了其对重油的降解效果。降解18d,重油的降解率达到42．8％,饱和烃、芳香烃、胶质、沥青质的降解率分别为42．95％,43．85％,44．5％,5．55％;质量浓度2．5g／L的表面活性剂Tween-80可使重油的18d降解率达到51．0％;弱碱性条件有利于重油的生物降解;生物泥浆法处理重油污染的土壤,1kg土壤中重油质量100g,降解45d,重油的降解率达到38．85％。     

Oil/Suspended Particulate Material Interactions and Sedimentation

The interactions of physically dispersed oil droplets with suspended particulate material (SPM) can be important for the transport of bulk quantities of spilled crude oil and polycyclic aromatic hydrocarbons (PAH) to subtidal sediments. The literature regarding oil/SPM interactions is reviewed, and results from whole-oil droplet/SPM interaction kinetics and pure-component (Prudhoe Bay crude oil distillate cut) equilibrium partitioning experiments are presented. The effects of oil type, SPM characteristics, and salinity on the interaction rates are examined, and the importance of whole-oil droplet/SPM interactions on particle agglomeration and settling behavior are discussed. Whole-oil droplet/SPM interactions are retarded as oil droplet dispersion into the water column is inhibited by oil viscosity increases due to evaporation weathering and water-in-oil emulsification. Compared to whole oil droplet/SPM interactions, dissolved-component/SPM adsorption is not as significant for transport of individual components to sediments. The information presented in this paper can be used to augment computer-based models designed to predict oil-spill trajectories, oil-weathering behavior, and spilled oil impacts to the marine environment.     

壳聚糖复合吸附剂对油的吸附性能

以天然可生物降解的壳聚糖和硬脂酸为原料,通过壳聚糖2位氨基与硬脂酸的羧基相互作用,引入疏水烷基链,制备了疏水的壳聚糖-硬脂酸复合吸附剂(简称复合吸附剂),采用傅立叶红外光谱、X射线衍射对复合吸附剂的结构进行表征,并考察了复合吸附剂对油的回收性能.实验结果表明:壳聚糖和硬脂酸以离子形式结合得到复合吸附剂;当硬脂酸与壳聚糖质量比为0.7时,硬脂酸的结合量最大;复合吸附剂对油的吸附量、保油率、脱附率的顺序分别为花生油(14.93 g/g)>甲基硅油(10.71 g/g)>液体石蜡(9.37 g/g),花生油(94.51%)>液体石蜡(90.74%)>甲基硅油(78.69%),花生油(95.62%)>液体石蜡(93.27%)>甲基硅油(90.73%).