This paper is a continued study of the work presented in SPE 13041, "Improved Bulk Blending presented in SPE 13041, "Improved Bulk Blending Techniques for Accurate and Uniform Cement Blends." Further investigation was conducted to better understand the factors which affect the physical performance of a cement blend, specifically the performance of a cement blend, specifically the thickening time. The variability of neat cement was found to be one of the main elements affecting the thickening time. Cement samples from one load of cement and samples from many different loads were seen to differ significantly in thickening time. It was determined that standard thickening time tests do not necessarily indicate the true responsiveness of a cement. Effects of sampling procedures on thickening times and additive distribution were investigated. Placement of sample valves was found to be an important factor affecting the sampling. Using proper sampling procedures and by conducting pilot tests with the same cement used to blend a pilot tests with the same cement used to blend a job, thickening times can be correlated between the laboratory and the field. The effects of offshore transportation and transfer of cement blends to the H g were also examined. The uniformity of the cement did not change with the transfer from the boat to the rig with hematite or retarding additives. Introduction Because cement slurry design has become so complex being able to deliver a slurry with the designed thickening tine has become more critical. It was noted that after assuring that the design was properly blended and the blend verified for additive properly blended and the blend verified for additive concentrations as described by Pace that in many cases the thickening times using samples blended in the lab (pilot blends) differed significantly from the times obtained from bulk house samples an samples. Research was started to determined these thickening times varied. The first and main element investigated was the neat cement. The neat cement was found to have varied responsiveness even in samples from one truckload of cement (50,000 lbs. or 22,675 kg.). During the course of the investigation it was noted that a group of cement samples will respond the same at low temperatures, but drastically different at high temperatures. It was found that the best correlation between pilot tests and field blends was accomplished when a pilot test was run immediately prior to blending with cement from the silo used for prior to blending with cement from the silo used for the field blend. Sampling procedures were also suited to determine their effects on the additive distribution and the thickening times. Placement of the sample valve played a critical role in obtaining representative samples. After determining the proper placement of the sample valve and using a proper placement of the sample valve and using a controlled amount of air pressure when sampling, the correlation between pilot blend thickening times and field blend thickening times was very good. The effects of transferring a cement blend from a boat at sea level to rig tanks about 100 ft (30 m) above sea level was investigated. Hematite blends and low quantity fluid loss and retarder additive blends were both studied during the transfer to the rig. It was observed that the uniformity of the cement blend did not change during the transfer from the boat to the rig. VARIABILITY OF NEAT CEMENT For years it has been known that cement varies from manufacturer to manufacturer. Service companies and oil companies know that when suppliers are changed the pilot testing for a job needs to be repeated. Laboratory cement samples are normally obtained from the cement supplier or from a company bulk facility.

Summary Considerable time is lost during field operations waiting for cement-thickening times to be determined. Our method to minimize the amount of waiting time is a colonmetric procedure based on Basic Blue 9 dye for determining a relative measure of the thickening time for a cement blend. This test is applicable to any field blend regardless of the additives used, and can be run in a matter of minutes rather than hours. Introduction Consistometer thickening-time tests always have been used to establish whether a particular field blend will perform as expected downhole. These tests involve use of expensive equipment and one test sometimes requires an entire working day or more to complete. The consistometer thickening times are costly because of the equipment involved, the manpower costs associated in running the tests, and the time lost in the field. The chemical method presented here was developed to minimize the number of samples run on the consistometer and thus to reduce the time and cost factors involved. The primary application of the chemical thickeningtime test is to verify the blended composition of field mixtures relative to a laboratory-prepared pilot mixture. Specifically, it is designed to monitor the uniformity of the blending process when blending large jobs. Each 100- to 200-sack portion of the total amount to be blended-a "drop"-is tested and compared to the pilot blend to ensure that the entire slurry will be uniform downhole. This test can be a substitute for rerunning consistometer thickening-time tests when time does not permit additional testing. The method also can be used to provide quality-control analyses for additives that normally require consistometer thickening-times. Data presented support the use of colorimetric determination to monitor thickening time, provided that a pilot blend that has had its thickening time measured on a consistometer is used as a standard. This approach also can be used to design slurries without repeated thickening-time determinations. This is accomplished by preparing two standards that bracket the desired thickening time. Theory The chemical thickening-time test is based on a colorimetric procedure that measures the amount of ionic dye in cement filtrate. Young proposes that cement particles have active sites onto which various additives are adsorbed. When cement is blended and hydrated, the additives are exposed thoroughly to these active sites and are adsorbed onto the cement particles. This adsorption determines the performance of the cement with regard to such properties as thickening time and fluid loss. The ionic nature of the dye added after the cement has been hydrated allows it to be adsorbed onto the remaining active sites of the cement. It is the number of these vacant active sites that determines the concentration of dye left in the cement filtrate, and, therefore, becomes an indirect measure of the total additive concentration. Some of the additives that are used for extenders and for weighting materials are not adsorbed onto the cement, but these additives have active sites that are very similar to those on cement. JPT P. 321^

Environmental stewardship has been and continues to be a critical component of the oil and gas industry, as exploitation of shale and other unconventional gas reservoirs requires large volumes of water for economic and efficient production. Evaluating and communicating the hazards of chemicals is done in a highly variable manner across the world. However the recent adoption of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) by multiple Global regulatory bodies has brought international consensus to hazard criteria and definitions. This system is being implemented with REACH in the EU. In the US OSHA has just proposed the GHS criteria as the basis for modifying their hazard communication regulations. This standardization ensures information about hazards and toxicity of chemicals is more universally available, to enhance protection of human health and the environment during handling, transportation and use. It is this scheme that we are beginning to utilize as the basis for the ranking of products and systems. This paper will describe the evaluation and implementation of a practical and quantitative process of ranking well servicing products based on their safety, health and environmental impacts. The ranking allows operators to select and use products that best fit their environmental stewardship goals, and provides scientifically sound tools for better research and development, and educational efforts.

Two of the major factors affecting cement slurry performance are the concentration of additives and their distribution throughout the dry cement blend. Consistometer thickening time tests on one or two batches of the cement are used to monitor the cement blends. Studies conducted have proven that these tests do not necessarily reflect the uniformity or the correct concentration of additives in the blend. To improve the quality of the bulk blending of cement, researchers developed on-site methods to verify the additive concentrations of each batch blended for uniformity and accuracy. They also investigated the effects of the current dry blending procedures, transportation, and air blending on the distribution of such additives as retarders, fluid loss agents, weighting agents, and salts.

The supply of potable drinking water, nonpotable processed water and ultimately wastewater disposal is a significant cost and logistical concern in many areas of the world. Water conservation and the demand for potable drinking water poses a daunting task for operating bases. This paper outline challenges for facility management where water is a scarce resource through incorporating strategies and technologies for the water management cycle. The sourcing of potable water is an issue where nonpotable ground water is the only alternative to high- cost tank and bottled water. Utilizing technologies to generate on-site potable water where potable water supply is restricted provides companies the opportunity to increase their available potable water supply, and provides corporate social responsibility benefits to the community. Utilizing processed or nonpotable water, although more readily available, still poses issues for many locations because of arid conditions and water demand increasing logistics and cost of supply. This paper reviews strategies for sourcing and recycling technologies for nonpotable water to reduce impact. The final aspect of water management includes the challenges with regard to disposing of processed grey water and black water from washrooms and other sources in locations where municipal waste water treatment facilities are not available. In such areas, removal and waste water costs can be significant. Additionally, companies must maintain environmental oversight to ensure waste water is properly managed to protect the environment and company reputation. The paper presents waste water disposal management strategies to control risk and costs, utilizing techniques and technologies that reduce water quantity and levels of pollutants in discharged water. Case studies from facilities in Dubai UAE, Iraq, Brazil, and Algeria are presented to illustrate the process of holistic water management at service bases. The paper also introduces a water management tool developed to assess and quantify water management components, and the methodology to identify strategies and technologies for managing a facility’s water cycle. The approach encompasses the logistical, cost and social benefits of water management.