油田钻井废泥浆固化处理研究

文章结合油田的现场实际情况,针对该区钻井废泥浆污染物的特性,研究了固化的最佳工艺条件,并对固化效果进行评价。通过多组固化处理定性对比实验,从多种处理剂中筛选出处理效果较好的水泥、粉煤灰、石灰和黄土作为固化处理废泥浆的固化剂原材料。利用筛选出的固化剂组成,设计正交实验,确定固化剂最佳配方为每100mL泥浆添加10g水泥、20g粉煤灰、8g石灰、15g黄土。影响因素对固化处理效果的影响实验结果表明:当废泥浆固相含量在30%～70%,固化温度在20～40℃之间,固化时间能够满足7d的条件下,固化效果最佳。     

镉污染土壤的固化研究

实验采用土壤固化技术,研究水泥、粉煤灰、石灰与土壤不同配比对镉污染土壤固化效果影响,结果表明:水泥、石灰、粉煤灰3种固化剂都能有效地对镉污染土壤进行固定化处理,并且随着固化剂比例的增加,固化体抗压强度越高,重金属浸出浓度越低。3种固化剂的固化效果也不同,实验结果分析表明水泥对固化效果的影响最大。当水泥、石灰、粉煤灰混合使用时,固化效果比单独使用时固化效果好,最佳固化比例为水泥用量300%,粉煤灰用量30%,石灰用量10%。     

一种废钻井液固化剂的研制与应用

研制以固体固化剂SD和饱和盐溶液SG为基础的复合固化剂体系,通过废钻井液的高效、高强度固化,实现废钻井液的无害化处理。通过优选固化剂SD、SG配方及加量,并经过固化机理分析和固化效果评价,研制出一种适用于现场作业的高效、高强度固化剂。在100 g废钻井液中加入21 g复合固化剂后,固化 物即可达到较高的强度3.75MPa,浸出液毒性较低;加入固化剂28 g后,浸出液可满足GB 8978—1996《污水综合排放标准》二级要求（COD＜150mg/L,色度＜80）。固化4h后即可形成可运输的固化物。复合固化剂SD/SG原料价廉易得,配制、使用方便,处理费用低,具备较强的推广应用价值。选取两口井,进行现场试验,废 钻井液使用该固化剂固化后,重金属含量满足GB 15618—2018《土壤环境质量 农用地土壤污染风险管控标 准》,其浸出液检测满足GB 5085.3—2007《危险废物鉴别标准浸出毒性鉴别》要求。     

固化剂在钻井液不落地生产中的应用

选用5种固化剂对钻井液进行室内固化试验和现场应用研究。抗压强度试验结果表明:脲醛树脂、丙烯酞胺凝胶体、无机固化剂高炉矿渣、无定形硅粉及复合固化剂CQGH-1中,复合固化剂CQGH-1固化效果最好,固化体抗压强度最大;对5种固化剂形成的固化体浸出液进行铜、锌、镉、铬和铅等含量分析,结果表明:复合固化剂CQGH-1固化体浸出液达到GB 5085.3—2007《危险废物鉴别标准浸出毒性鉴别》要求,从而得出CQGH-1为最佳固化剂。进行了最佳加量试验,得出最佳加量为25%。现场应用表明,CQGH-1固化效果好,固化体浸出液满足GB 5085.3—2007《危险废物鉴别标准浸出毒性鉴别》,且复合固化剂CQGH-1经济效益优于传统固化剂。     

钻井泥浆固化处置对地表水环境影响

选取四川省境内比较有代表性的5处井场,通过进行不同水泥固化剂处理效果的对比,包括固化体样品性状对比及固化体浸出液污染因子监测数据对比,分析以水基泥浆为原泥浆的钻井废泥浆固化处理工艺的效果,以及现有常用固化处置对周边地表水环境的影响。     

废钻井液固化处理实验研究

通过大量实验,分别探讨了数种无机和有机添加剂的加量、时间、温度等因素对废钻井液固化效果的影响,优选出对固化处理废钻井液有显著效果的固化剂及相对较好的添加剂配方a、b,并对其固化机理进行了初步分析。实验结果表明:a配方可作为填充物的最佳配方,其主要指标都已达到国家二级排放标准和GB3550—83标准;b配方用于道路施工,其抗压强度和抗塌落程度已达到国家二级公路标准。     

废弃水基钻井液固化处理研究

废弃水基钻井液固化处理是当前油田环保急需解决的问题之一。研究利用油田的几种废弃水基钻井液,选择固化技术对其进行固化处理,探讨几种无机和有机添加剂对处理效果的影响,优选相对较好的添加剂配方,并对其固化机理作了初步分析。结果表明：采用无机胶凝剂和少量有机固化剂配制的复合型团化剂,固化效果较好,固化物的浸出液毒性均在ＧＢ３５５０－８３控制的指标之内,成本低廉,收到较好的社会与经济效益。     

油田废污泥治理研究

冀东油田废水池地处环境敏感区域，对其废污泥采用固化法进行处理。在大量实验的基础上优选出了三种固化剂体系并通过多次浸泡实验、淋洗实验和静态浸出实验对固化效果进行了分析。     

废弃钻井液处理技术研究

文章分析了废弃钻井液的研究现状及处理方法,包括:简单处理再利用法、注入安全地层或井的环形空间法、回填处理法、MTC转化技术法、固液分离法、坑内密封法、土地耕作法、再回收利用法、微生物降解法、固化处理法。得出:固化处理法为各大油田最为常用的处理方法,前景较好。开发并研制高效环保的固化剂或复合固化剂,降低处理费用,固化体的再次利用等是废弃钻井液固化处理技术的发展方向。     

废弃钻井泥浆的固化处理

废弃钻井泥浆的处理是油气勘探与开发工业中人们极为关注的。文章在分析废弃钻井泥浆性质的基础上，通过化学稳定与固化处理试验研究得出以水泥为主，烟炭，石灰等为添加剂的固化剂配方，实验结果表明，经固化处理的废弃泥浆，其固化产物重金属浸出率低，稳定性好，具有一定的抗氧强度，从而能有效地降低废弃泥浆对环境的污染危害，文中还对各种辅加剂对固化效果的影响进行了分析。     

Forestry policy and woodfuel markets in Malawi

Forestry and energy policies in Malawi place the blame for the country's high rate of deforestation on the demand for woodfuel. The government has been involved in a range of questionable supply-side initiatives, as well as in a number of interventions in woodfuel markets, with the objective of slowing rates of deforestation. It seeks to encourage farmers to grow woodfuel to meet market demands, and has provided subsidies to do so. The Forest Department has kept prices for firewood from its plantations low, both in order to discourage the market for wood from free resources and because of concerns about the impact of high producer prices on the urban poor. In doing so, the government is less able to rely on the market to provide producers with the incentive to plant trees to meet market demands. In any event, the market accounts for a relatively small proportion of total woodfuel demand. Policies do not distinguish between rural household demands and the specific market demands which are having the greatest impact on deforestation: woodfuel for urban markets, for tobacco curing, and for small industries. These, coupled with the expansion of the estate sector, have had afar greater impact on woodland clearance than rural, subsistence woodfuel demands. Rural household energy demands need to be addressed from a much broader perspective which considers the household's larger needs for tree based products or outputs: income, food, fibre, fodder, soil fertility, as well as for fuel .     

Can oligopsony power be measured? The case of U.S. old newspapers market

This paper uses an index analogous to Lerner-index in the input market to derive a price–cost margin that measures input exploitation by few large buyers. This paper identifies oligopsony characteristics associated with the old newspaper (ONP) input market for recycled-content newsprint manufacture and then examines the impacts of market performances on ONP input prices. The wastepaper recycling market, in particular, ONP has not been successful in utilizing the ONP generated. The existence of high sunk costs for entry to the market, along with the small numbers of buyers in the old newspapers market, were the reasons to believe that the waste paper industry had oligopsony elements among paper recycling mills. The regional oligopsony/oligopoly indices were derived and the impact of these market powers on ONP input prices were examined for period 1972–1995. The findings of this study were: oligopsony elements were present to certain degrees among the recycled-content newsprint manufacturers; and the oligopsony market power enabled these mills to exert a larger price–cost margin on ONP input market.     

Mixed signals: market incentives, recycling, and the price spike of 1995

Environmental economics assumes that reliance on price signals, adjusted for externalities, normally leads to efficient solutions to environmental problems. We explore a limiting case, when market volatility created ‘mixed signals’: prices of waste paper and other recycled materials were suddenly extremely high in 1994–1995, then plummeted back to traditional low levels in 1996. These rapid reversals resulted in substantial economic and political costs. A review of academic and business literature suggests six possible explanations for abrupt price spikes. An econometric analysis of the prices of wood pulp and waste paper shows that factor which explained price changes in 1983–1993 contribute very little to understanding the subsequent price spike. From the econometric analysis and from other sources, we conclude that speculation must have played a major role in the price spike, perhaps in combination with modest effects from changes in government policy and in export demand. If speculatively driven price spikes can disrupt an environmentally important industry such as recycling, what is the appropriate role for public policy? When price volatility is sufficiently disruptive, then measures to control or stabilize prices, rather than interfering with the market, might help to make it more efficient.     

Forecasting precious metal price movements using trader positions

In the early 2000s, the precious metal markets entered into a new phase where a steady rise of prices had been observed until the October 2008 crash. Given the size and importance of precious metal market, as well as the hedging capacity of precious metals due to their low correlation with equity markets (Draper et al., 2006), the question we want to arise is whether trader positions predict the direction of gold, platinum, and silver spot price movements. The forecasting content of the Commodity Futures Trading Commission’s Commitment of Traders report for platinum, silver and gold prices using trader positions is investigated in a VAR framework. Granger causality tests are conducted to determine whether a relation between trader positions and market prices exists. An examination of the extreme trader positions on price movements is also conducted. The results indicate that market return is a significant parameter in explaining trader’s positions for all trader types in each of the precious metal markets under consideration after the beginning of 2000s where we detect a structural break for each of the market under study. Commercial traders are found to be negative feedback traders, that is, they sell when the prices increase in the market. On the other hand, in line with the previous literature, a positive correlation between returns and positions held by non-commercial and non-reporting traders is found. However, trader’s net positions do not lead market returns in general. There is some evidence on the forecasting ability of extreme trader positions on market returns.     

Forward pricing and efficiency in the silver market

If futures prices ‘fully reflect’ all available information, then these prices may be interpreted as market anticipations of spot (cash) prices at the delivery date of the futures contract. This hypothesis, which has tended to find most support among established markets for storable commodities, is investigated for the Chicago silver futures market. Using instrumental variable estimation and a joint (χ²) test, the unbiased prediction hypothesis is rejected, and a tentative explanation is offered for this outcome. This result, however, does not necessarily imply that the market is inefficient, and two tests of the weak form efficient markets hypothesis suggest that, while there is some slight dependence in past prices, this is only marginally more than would be expected from normal sampling variation.     

Investor demand and spot commodity prices

The on-going debate over the influence of investor demand on spot commodity prices largely attempts to assess this influence by measuring the growth in investor demand in recent years. Given the serious data problems that plague such analyses, this article pursues another approach in the hope of providing useful insights into the impact of investor demand on spot commodity prices. It focuses on the mechanisms by which investor demand affects spot prices, and in particular on two questions. First, how does an increase in investor demand on the futures markets affect the spot market and spot price? Second, when investor demand is increasing and pushing a commodity's price up, do physical stocks of the commodity also have to be rising, as economists and others widely assume?On the first question, the article concludes that a surge in investor demand raising prices on the futures markets will have a direct and comparable effect on the spot market prices when these markets are in strong contango. However, when markets are in weak contango or backwardation, price movements in the futures markets have a much looser effect on spot prices. As a result, changes in investor demand on the futures markets may have little or no influence on spot prices in the absence of a strong contango. Instead, changes in fundamentals (that is, producer supply and consumer demand) and possibly changes in investor demand taking place directly on the spot market largely determine the spot price at such times.On the second question, the article shows that investor demand can be pushing up a commodity's price even when investor stocks are falling, despite the widespread presumption to the contrary.     

Alumina market trends in the 1990s

During the past decade, alumina prices have been highly volatile, so much so that it has endangered the existence of some producers, and limited the ability of some smelters to benefit from higher aluminium prices. Although certain trends can be identified for the 1990s, some factors could again result in large price fluctuations in the alumina market. After a review of those identified trends and factors, this paper attempts to focus on ways to limit the effect of fluctuations in the non-integrated alumina market.     

Long-term iron ore price modeling: Marginal costs vs. incentive price

The paper studies and applies the approaches to forecast long-term (LT) real prices of iron ore. This price is crucial for valuation of investments in Greenfield iron ore projects on the horizon of more than 5 years. The forecast is obtained by three different approaches which are usually used by investment bank analysts: marginal costs approach and 2 approaches based on calculation of incentive price. The paper concludes that there has been a structural shift on the iron ore market and LT iron ore prices will be higher by 20–30% than the average of industry forecasters suggest. This is related to the 2 key factors which were taken into account in this study—depletion of existing iron ore deposits and targeted return on investments for new projects. In addition, escalated industry costs inflation is claimed to be the factor which will bolster nominal iron ore prices at high levels in the long-term. Using a Monte-Carlo simulation approach, confidence interval for future iron ore price was estimated.     

油气田污泥无害化处理途径探讨

我国污泥处理和处置研究起步较晚,大部分为农田堆肥处置,这对环境保护有不良的影响。在室内进行了油田污泥固化试验研究。研究结果表明:水泥固化污泥可用于制作筑路材料,以水泥、石灰、水玻璃为主要固化剂的污泥可进行填埋处理,含油污泥可制成煤球,可将含油污泥焚烧处理,可以用污泥焚烧灰制砖。这些方法都是污泥后续无害化、资源化处理的有效手段。