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Wellbore cement has been used to provide well integrity through zonal isolation in oil and gas wells as well as geothermal wells. Failures of wellbore cement result from either or both: inadequate cleaning of the wellbore and inappropriate cement slurry design for a given field/operational application. Inadequate cementing can result in creation of fractures and microannuli, through which produced fluids can migrate to the surface, leading to environmental and economic issues such as sustained casing pressure, contamination of fresh water aquifers and, in some cases, well blowout. To achieve proper cementing, the drilling fluid should be completely displaced by the cement slurry, providing clean interfaces for effective bond. This is, however, hard to achieve in practice, which results in contaminated cement mixture and poor bonds at interfaces. This paper reports findings from the experimental investigation of the impact of drilling fluid contamination on the shear bond strength at the cement-formation and the cement-casing interfaces by testing different levels of contamination as well as contaminations of different nature (physical vs. chemical). Shear bond test and material characterization techniques were used to quantify the effect of drilling fluid contamination on the shear bond strength. The results show that drilling fluid contamination is detrimental to both cement-formation and cement-casing shear bond strength.

What is rising dampness? Rising dampness results from the upward capillary flow of water from ground into masonry. The force responsible for the flow is associated with the surface characteristics of water (particularly the surface tension), but is not a unique property of water. For example, upward capillary flow occurs in the wick of a paraffin heater, and carries molten wax up the wick of a candle. In the case of a wall not protected by a damp‐proof course, the process is a continuous one and the water will rise upwards and spread laterally to the wall surfaces until the rate of ingress is balanced by the evaporation from the wall surfaces.

In the summer of 2014, a large energy company was poised to begin expanding its unconventional natural gas operations in northeastern British Columbia in the hopes of capitalizing on the Canadian province's determination to build a liquid natural gas industry. The company had secured mineral rights from the province but had not simultaneously pursued surface rights from a First Nation community that historically had used the land. When a seismic exploration team appeared on the tribe's traditional territory without consulting it, as was customary (and in some cases legally required), the company unwittingly ignited a firestorm of protest from both First Nation and non First Nation local citizens. Recognizing the importance of social acceptance both to operations and profitability, the company sent senior vice president Maria Paquet to participate in fireside discussions with tribal, regional government, and environmental leaders in the hopes of finding some common ground. Could these leaders arrive at sufficient trust and agreement to allow the company to move forward with its plans? Or would the company face gridlock, community blocking, or even financial peril? In a small-group role-playing exercise, students will step into the shoes of each of these stakeholders as they try to forge a path forward that is acceptable to all.

The purpose of this study is to determine the possibilities to use drill cuttings in soil formation processes on sandy substrates. The ecological and toxicological assessment of drill cuttings of various genesis and mixtures based on them is applied for the purpose.

Acute toxicity of mixtures consisting of various drill cuttings, sand and peat was estimated using soft wheat seeds (Triticum aestivum) using the eluate method. Subacute toxicity experiments were carried out using creeping trefoil (white clover) seeds (Trifolium repens), rye seeds (Secale cereale), and garden radish seeds (Raphanus sativus L.). Drill cuttings of the West Siberian oil-and-gas basin generated as a result of drilling on clay-polymer drilling fluids can be used as a component of soil-like mixtures in the reclamation of sand fills. Patterns of the selective stimulation of seed growth by components of drilling fluids (xanthate and bentonite) were revealed.

It was found that the addition of bentonite and xanthan (0.05% by weight of the cuttings each) reduces the suppression of seed growth occasioned salt content by 21.1% and 24.0%, respectively.

Soil degradation and desertification is a serious and widespread problem. The restoration of the fertile layer can be launched by application of the artificial soil-like mixtures based on drill cuttings of a certain origin to the disturbed lands.

An appreciation of the material from which modern printed circuit board drills are fabricated and an understanding of the salient geometric design features incorporated in such tooling will help those involved with the drilling process in determining optimum operating procedures and in identifying the underlying causes of hole deficiencies.

This paper aims to provide a detailed review of various cutting fluids (CFs).

Friction and wear are inevitable in machine parts in motion. The industrial sector uses various kinds of lubricants, which include engine oils, CFs, hydraulic fluids, greases, etc. to control friction and wear. The main purpose of using CF is to remove heat produced during machining and to reduce cutting forces, tool wear and energy associated with it. Thus, it increases the productivity and quality of the manufacturing process. But more than 80% of the CFs used in the industries now are mineral oil-based. These mineral oils and additives are highly undesirable because of their toxicity, nonbiodegradability, pollution and ecological problems. Hence, these petroleum-based oils in the lubrication system can be substituted with alternatives such as vegetable-based CF. Several studies are being conducted in the field of eco-friendly CFs. Because of the variance in fatty acid profile and availability, the selection of vegetable oils (VOs) is another problem faced nowadays. The present study is focused on bio-based oils and many eco-friendly additives. Various machining processes and comparisons relating to the same have also been made. The aim is to minimize the use of mineral oil and thereby introduce sustainability in production.

In this present study, bio-based oils, additives and various characteristic behavior of them in machining are being discussed. The VOs are found to be a potential base oil for industrial CFs.

This paper describes the importance of sustainable CFs.

In recent years, to solve the contradiction between energy supply and demand, the Chinese Government has vigorously promoted shale gas development. With the rapid development of the shale gas industry, the environmental impact problems have become increasingly serious. Therefore, it is of great significance to carry out a comprehensive environmental impact assessment of shale gas development. This study aims to provide a theoretical basis for enterprises to make development decisions on shale gas projects by constructing a model of comprehensive environmental impact assessment for shale gas development.

In this paper, the comprehensive environmental impact factors of shale gas development are analyzed from the two aspects of the natural environment and macro environment, and the index system of comprehensive environmental impact assessment for shale gas development including 7 secondary indicators and 24 tertiary indicators is constructed. Owing to the fact that qualitative indicators are difficult to quantify in the evaluation process, the method of intuitionistic fuzzy analytic hierarchy process (IFAHP) is adopted for evaluation. This method (IFAHP) can delicately describe the hesitancy degree of the decision-makers in the process of assigning a weight to the indicators, and make the weight assignment of each index more accurate. Furthermore, this method overcomes the shortcomings of the conventional methods, such as the complexity of calculation and the large amount of calculation.

The evaluation model is applied to a shale gas platform drilling project in Southwest China. Based on the ratings from 13 experts, the comprehensive environmental impact assessment grade of this project is good, indicating that the shale gas development project is feasible. The result is basically in line with the actual situation.

Based on the consideration of the natural environmental impacts of shale gas development, this paper also has considered the macro environmental impact of shale gas development, and has established the index system of comprehensive environmental impact assessment for shale gas development from the two aspects of the natural environment and macro environment. To overcome such difficulties as incomplete evaluation by decision-makers, cumbersome calculation process and a large amount of calculation, this paper has adopted the method of IFAHP to evaluate and has established a comprehensive environmental impact assessment model for shale gas development based on IFAHP.

Concrete used in building construction does not demand a high level of sophistication in its manufacture but if certain basic rules are not observed it can give trouble.

Outlines some of the relevant work that FeRFA (the trade Federation representing manufacturers, raw material suppliers and contractors of resin based flooring systems) has initiated to improve standards in upgrading existing industrial ground floor surfaces. Describes the properties of resin and concrete, discussing resistance to impact, wear, chemicals, heat and fire, and its porosity. Illustrates the types of resin materials available, and its adaptability. Details the approach required in order to properly assess the existing floor conditions.