泥水盾构废弃泥浆絮凝脱水机理及影响因素分析

为明确泥水盾构废弃泥浆固液分离性能,提高泥浆固液分离效率,采用化学絮凝的方法对建筑废弃泥浆快速泥水分离性能进行了试验研究,开展了不同种类聚丙烯酰胺(PAM)作用下废弃泥浆絮凝沉降试验、颗粒级配试验及浊度试验研究,考察了药剂种类(APAM、NPAM、CPAM)、分子量及用量对废弃泥浆絮凝沉降特性的影响规律。试验结果表明：APAM和NPAM对废弃泥浆固液分离效果显著,CPAM对废弃泥浆并无明显絮凝作用;对于APAM而言,当其分子量分别为1200万,1600万和1800万时,废浆絮凝效果最佳时的添加量分别为0.35g/L、0.3g/L和0.25g/L;对于NPAM而言,当其分子量分别为1200万,1600万和1800万时,废浆絮凝效果最佳时的添加量分别为0.3g/L、0.3g/L和0.25g/L,且在最佳添加量的情况下,底泥体积、底泥含水率和上清液浊最小,泥浆粒径参数D50最大;APAM与废弃泥浆颗粒之间的作用方式主要是“吸附架桥连接”,NPAM与废弃泥浆颗粒之间的作用方式主要是“电性中和”与“吸附架桥连接”。     

污水灌溉对水稻、玉米、小麦籽粒中粗蛋白、粗脂肪含量的影响

为了探讨污水灌溉对水稻、玉米、小麦质量的影响,1979年我们在对水磨河、米泉污灌区的农业环境质量普查中,对灌区内的上述三种作物籽粒中的粗蛋白、粗脂肪的含量进行了分析测定,并与清灌区对照,所得结果如下: 从表中可以看出污灌后,水稻、玉米、小麦籽粒中粗蛋白的含量均略高于对照,增长幅度为0.9—2.9%,粗脂肪在玉米籽粒中亦有所增加,而且水稻、小麦中则有所减少。这说明污灌会引起作物产品中营养成分的变化,这种变化不仅会因营养成分不同而异,也因作物种类不同而变化。     

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。     

城市建筑泥浆的管理现状、污染问题及对策建议

建筑废弃泥浆含水率高,是一种悬浊浆体,以下阐述了建筑废弃泥浆的来源、污染问题、管理现状和存在的问题,并针对这些问题探讨了相关的管理对策,建筑废弃泥浆是由工程施工中产生的,施工点土壤本身受到污染、施工过程利用的水源受到污染、泥浆泵管油污未清洗干净等,这些都会导致建筑泥浆的污染问题,而中国现今仅有绍兴等城市制定了建筑废弃泥浆的管理条例,管理一体化机制还在起步阶段,故要在完善建筑泥浆处置的相关法规制度的基础上,采取政府主导、规范市场、科学管理、资源再利用等措施,实现泥浆减量化、资源化和无害化的防治目标,并对泥浆处置的发展趋势简单分析,为建筑废弃泥浆处置管理的探索实践提供建议。     

钻井泥浆固化处置对土壤环境的影响

针对四川地区油气田产生钻井废泥浆的特点,选取代表性的井场平台,进行现场调查和固化体取样实验,并将量化的数据定性化,得出固化处理钻井废泥浆对环境影响的程度,再通过对较差的井场进行土壤环境质量监测,最终分析钻井泥浆固化处置对土壤环境的影响及应采取的相应措施。结果表明：采取废弃泥浆固化方法效果较好,对周围土壤环境影响小。     

玉米新品种南七单交的选育和应用

玉米新品种南七单交的选育和应用李蜀西（四川省万县市农业科学研究所，万县６３４６００）１品种选育Ｂ的和依据玉米对温光的反应不象小麦、水稻那样敏感，无明显的春化和光周期效应，是一个适应性很广泛的作物。中单２号的育成标志我国玉米育种史上出现了一个新的面貌，...     

MEG环保泥浆在王庄油田强水敏储层的应用

王庄油田属强水敏储层,过去采用污染强、费用高的油基泥浆、强抑制泥浆,对周边环境影响较大,施工费用高。针对上述情况,在分析MEG(甲基葡萄糖苷)环保泥浆优势的基础上,通过实验室对比和现场应用对比,研究MEG泥浆的应用效果及其固化浸出液对环境的影响。结果表明,MEG钻井液固化浸出液满足GB 8978—1996《污水综合排放标准》的一级标准要求,固化泥浆池固化后对周边土壤环境影响不大,不影响作物的正常生长。     

钻井废弃泥浆脱水工艺试验

在分析钻井废弃泥浆组成的基础上,对泥浆体系进行稀释、酸化处理,以硅改性聚合氯化铁为破胶剂,阳离子聚丙烯酰胺为絮凝剂,破坏钻井废弃泥浆的胶体体系,采用固液分离方法使泥浆液混凝脱水。试验表明:稀释倍数为4倍、pH值为5、2.5%改性聚合氯化铁为破胶剂、0.25‰阳离子聚丙烯酰胺为絮凝剂、0.8%N-626为去油剂,离心分离后泥饼中石油类含量低于3‰,混凝产生的絮体大、脱水率高、残渣稳定性好、无造浆能力。     

2004—2013年中国粮食生产变动贡献因素分解

利用2004—2013年中国粮食生产相关数据,基于改进的拉氏因素分解方法建立粮食产量变动因素分解模型,定量分析了耕地面积、复种指数、粮作比例、作物单产和种植结构对粮食产量变动的影响。结果表明:1研究期中国粮食增产受播种面积扩大和加权平均单产提高共同驱动,两者平均贡献率分别为35.17%和64.38%。2研究期粮食播种面积持续增加受耕地面积、复种指数和粮作比例三个因素共同驱动,其中复种指数效应居绝对主导地位,平均贡献率为92.6%。3研究期中国粮食加权平均单产快速提高。从作物贡献角度看,玉米、小麦和稻谷的单产变化效应发挥主导作用,三者合计的平均贡献率为115.70%;从生产力效应和结构效应的综合作用看,生产力效应是粮食加权平均单产变化的主导因素,平均贡献率为75.09%,但作物结构效应的贡献不容忽视。     

油气田钻屑与废泥浆固化处理技术的初步研究

由于钻井废弃泥浆流失会对环境造成严重污染，所以必须对废弃泥浆进行固化处理。通过大量实验研究，筛选出了分别适合于钻屑与高密度（ρ〉2.0g／cm^3）、中密度（ρ=1.6g/cm^3左右）、低密度（ρ=1.2g/cm^3左右）钻井废泥浆的几种固化剂配方。现场结合具体情况选用实验筛选的固化荆配方对废钻井泥浆和钻屑固化处理，固化物的强度达到0.3MPa以上，固化物浸出液中污染物含量达到《污水综合排放标准》（GB8978-1996）一级标准要求。     

Management of mine spoil for crop productivity with lignite fly ash and biological amendments

Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996-2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200 t/ha), with and without press mud (10 t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50 t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20 t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p < 0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20 t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5-10.2% with various dosages of LFA. The optimum dosage of LFA was 20 t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20 t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20 t/ha and repeat applications at 50 t/ha. One-time and repeat applications of LFA of up to 20 t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of gamma-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20 t/ha of LFA, the crop yield decreased significantly (p < 0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and gamma-emitters in mine spoil and crop produce is also discussed.     

Resource conservation strategies for rice‐wheat cropping systems on partially reclaimed sodic soils of the Indo‐Gangetic region,and their effects on soil carbon

The Indo‐Gangetic plain is characterized by intensive agriculture, largely by resource‐poor small and marginal farmers. Vast swathes of salt‐affected areas in the region provide both challenges and opportunities to bolster food security and sequester carbon after reclamation. Sustainable management of reclaimed soils via resource conservation strategies, such as residue retention, is key to the prosperity of the farmer, as well as increases the efficiency of expensive initiatives to further reclaim sodic land areas, which currently lay barren. After five years of experimentation on resource conservation strategies for rice‐wheat systems on partially reclaimed sodic soils of the Indo‐Gangetic region, we evaluated changes in different soil carbon pools and crop yield. Out of all resource conservation techniques which were tested, rice‐wheat crop residue addition (30% of total production) was most effective in increasing soil organic carbon (SOC). In rice, without crop residue addition (WCR), soils under zero‐tillage with transplanting, summer ploughing with transplanting and direct seeding with brown manuring showed a significant increase in SOC over the control (puddling in rice, conventional tillage in wheat). In these treatments relatively higher levels of carbon were attained in all aggregate fractions compared to the control. Soil aggregate sizes in meso (0.25‐2.0 mm) and macro (2‐8 mm) ranges increased, whereas micro (< 0.25 mm) fractions decreased in soils under zero‐till practices, both with and without crop residue addition. Direct seeding with brown manuring and zero tillage with transplanting also showed an increase of 135% and 95%, respectively, over the control in microbial biomass carbon, without crop residue incorporation. In zero tillage with transplanting treatment, both with and without crop residue showed significant increase in soil carbon sequestration potential. Though the changes in accrued soil carbon did not bring about significant differences in terms of grain yield, overall synthesis in terms of balance between yield and carbon sequestration indicated that summer ploughing with transplanting and zero tillage with transplanting sequestered significantly higher rates of carbon, yet yielded on par with conventional practices. These could be appropriate alternatives to immediately replace conventional tillage and planting practices for rice‐wheat cropping systems in the sodic soils of the Indo‐Gangetic region.     

临南油田污泥浆回注处理研究

临盘采油厂临南油田针对水质改性后固体废物急剧增加、处理难度大的问题,提出了将污泥浆回注入高渗储层的处理办法,并在夏52-414井进行了现场试验。试验结果表明,当污泥浆浓度为10%时,相当于含污泥15～20t,注入压力可稳定在11MPa。目前每天可以处理污泥浆150～200m3,完全能满足临南联合站全部产出污泥浆处理的要求。同时,在未加任何添加剂的情况下,污泥悬浮性很好,可以保证长时间连续注入的效果。     

Predicting cadmium concentrations in wheat and barley grain using soil properties

The entry of Cd into the food chain is of concern as it can cause chronic health problems. To investigate the relationship between soil properties and the concentration of Cd in wheat (Triticum aestivum L.) and harley (Hordeum vulgare L.) grain, we analyzed 162 wheat and 215 barley grain samples collected from paired soil and crop surveys in Britain, and wheat and barley samples from two long-term sewage sludge experiments. Cadmium concentrations were much lower in barley grain than in wheat grain under comparable soil conditions. Multiple regression analysis showed that soil total Cd and pH were the significant factors influencing grain Cd concentrations. Significant cultivar differences in Cd uptake were observed for both wheat and barley. Wheat grain Cd concentrations could be predicted reasonably well from soil total Cd and pH using the following model: log(grain Cd) = a + b log(soil Cd) - c(soil pH), with 53% of the variance being accounted for. The coefficients obtained from the data sets of the paired soil and crop surveys and from long-term sewage sludge experiments were similar, suggesting similar controlling factors of Cd bioavailability in sludge-amended or unamended soils. For barley, the model was less satisfactory for predicting grain Cd concentration (22% of variance accounted for). The model can be used to predict the likelihood of wheat grain Cd exceeding the new European Union (EU) foodstuff regulations on the maximum permissible concentration of Cd under different soil conditions, particularly in relation to the existing Directive and the proposed new Directive on land applications of sewage sludge.     

Management of Lignite Fly Ash for Improving Soil Fertility and Crop Productivity

Lignite fly ash (LFA), being alkaline and endowed with excellent pozzolanic properties, a silt loam texture, and plant nutrients, has the potential to improve soil quality and productivity. Long-term field trials with groundnut, maize, and sun hemp were carried out to study the effect of LFA on growth and yield. Before crop I was sown, LFA was applied at various doses with and without press mud (an organic waste from the sugar industry, used as an amendment and source of nutrients). LFA with and without press mud was also applied before crops III and V were cultivated. Chemical fertilizer, along with gypsum, humic acid, and biofertilizer, was applied in all treatments, including the control. With one-time and repeat applications of LFA (with and without press mud), yield increased significantly (7.0–89.0%) in relation to the control crop. The press mud enhanced the yield (3.0–15.0%) with different LFA applications. The highest yield LFA dose was 200 t/ha for one-time and repeat applications, the maximum yield being with crop III (combination treatment). One-time and repeat application of LFA (alone and in combination with press mud) improved soil quality and the nutrient content of the produce. The highest dose of LFA (200 t/ha) with and without press mud showed the best residual effects (eco-friendly increases in the yield of succeeding crops). Some increase in trace- and heavy-metal contents and in the level of γ-emitters in soil and crop produce, but well within permissible limits, was observed. Thus, LFA can be used on a large scale to boost soil fertility and productivity with no adverse effects on the soil or crops, which may solve the problem of bulk disposal of fly ash in an eco-friendly manner.     

Soil properties affecting wheat yields following drilling-fluid application

Oil and gas drilling operations use drilling fluids (mud) to lubricate the drill bit and stem, transport formation cuttings to the surface, and seal off porous geologic formations. Following completion of the well, waste drilling fluid is often applied to cropland. We studied potential changes in soil compaction as indicated by cone penetration resistance, pH, electrical conductivity (EC(e)), sodium adsorption ratio (SAR), extractable soil and total straw and grain trace metal and nutrient concentrations, and winter wheat (Triticum aestivum L. 'TAM 107') grain yield following water-based, bentonitic drilling-fluid application (0-94 Mg ha(-1)) to field test plots. Three methods of application (normal, splash-plate, and spreader-bar) were used to study compaction effects. We measured increasing SAR, EC(e), and pH with drilling-fluid rates, but not to levels detrimental to crop production. Field measurements revealed significantly higher compaction within areas affected by truck travel, but also not enough to affect crop yield. In three of four site years, neither drilling-fluid rate nor application method affected grain yield. Extractions representing plant availability and plant analyses results indicated that drilling fluid did not significantly increase most trace elements or nutrient concentrations. These results support land application of water-based bentonitic drilling fluids as an acceptable practice on well-drained soils using controlled rates.     

Agricultural Adaptation to Drought for Different Cropping Systems in Southern China under Climate Change

This study investigates agricultural adaptation to drought for different cropping systems in southern China. The study area was divided into three regions: South China (SC), South of the Yangtze River (SYR), and Southwest China (SWC). An index of agricultural adaptation to drought (D) was established. Our findings indicated that the average total crop water demand varied greatly among the regions from 1961 to 2010 in southern China. The maximum value was found in the SC region, followed by the SYR and SWC regions. The effects of droughts on different crops were noticeable. Frequent droughts were recorded in late rice than in early rice in the SC and SYR regions. Droughts in the SWC region mainly affected winter wheat. Moreover, the effects of droughts on crops varied during different growth stages. More frequent and serious droughts occurred during the crop critical flowering stage. Particularly, the frequency of moderate and severe droughts for late rice in the SYR region was 62% during the critical flowering stage. For the SC and SYR regions, the D values of early rice (0.29 and 0.29) were lower than that of late rice (0.31 and 0.33), respectively. For the SWC region, the D values of winter wheat and rice were both low, with averages of 0.16 and 0.29, respectively. Our study provides interesting insights for improving the drought defense abilities for different cropping systems by changing crop planting proportion on a regional scale in China.     

废钻井液对环境污染及固化处理室内研究

目前我国许多油田钻井井场位于稻田、麦田、虾池和鱼塘周围，而废钻井液中含有无机盐、重金属组分、油品及大量有机聚合物，其中有些是有害物质，一口井的废钻井液一般可达200～300m~3。这些废钻井液堆放在井场不进行处理会对周围环境造成较大污染。为此，如何处理这些废钻井液是目前令人极为关心的课题。本文分析了我国一些油田废钻井液的毒性；介绍了毒性提取、评价方法及其对土壤、植物和海洋生物的影响，同时重点介绍用化学固化方法处理废钻井液的结果。通过对现场的5个废钻井液的固化处理室内试验证实，废钻井液固化后有一定强度，其水浸出液清彻透明，达到排放标准，固化体可进行掩埋恢复地貌，也可作为建筑材料使用。     

废弃聚合物钻井液化学脱水处理技术的实验研究

在分析废弃聚合物钻井液组成的基础上，对采用化学固液分离无害化处理方法进行了实验研究。以部分水解聚丙烯酰胺（ＨＰＡＭ）、聚电解质Ａ为絮凝剂和混合酸为凝聚剂的复合絮凝剂配方，可以彻底破坏ＨＰＡＭ类型废弃钻井液的胶体体系，使废浆液絮凝脱水。通过３口井废钻井液样品的絮凝试验，加药剂后废浆液自然脱水率为２５％～３５％，１３．３ｋＰａ压差下抽滤出水率为５１％～６０％，絮凝残渣无再造浆能力。