Oilfield tubulars (typically metallic pipes) and other types of oilfield equipment are typically stored in outdoor areas and may be scattered around the field. Managing these types of inventory is challenging and costly, as it requires significant labor resources. Therefore, inventory inaccuracy is common, and data-driven decisions may not be possible in a timely manner. We propose the use of radio frequency identification (RFID) for tracking oilfield tubulars and similar, outdoor-stored, equipment. Our proposed application utilizes passive ultra-high frequency (UHF) RFID technology that enables capturing unique serial identification numbers that are attached to inventory items from a distance of several meters. Passive UHF RFID tags require no batteries to operate. Typical tag cost is low. Each tag is placed on an inventory item and corresponds to a database entry containing specific information about this item. The tag communicates its serial number using power provided by an RFID reader radio transmission. The RFID reader is securely mounted to the underside of a UAV flown over the field. Captured RFID tags are either stored locally and retrieved once the UAV lands, or are wirelessly transmitted to a constantly updating inventory database. In addition to tag ID, the captured data typically includes time and date stamp, as well as location data. This research project included the design and manufacturing of an enclosure to house a RFID reader system which includes a host computer, embedded reader, antenna, power source, and necessary components for user interface. Specialized mounts were designed and manufactured to attach the enclosure and antenna to the UAV. The project incorporated the development of "middleware", specialized software installed on the host computer to communicate with the reader. The reader handles low-level communication with the antenna. To reduce network traffic, event management and data filtering are efficiently performed. The results of several UAV flights in experimental areas are presented and discussed. Various brands of passive RFID tags for oilfield applications were tested. Particular attention was given to population density of the items, stacking configuration, vertical altitude distance between reader and tags, and time to collect inventory data for a given area of surveillance. As RFID applications are increasing in the oil, gas, solar, and other sectors of the energy production industries, UAVs can effectively be used to get important operational and inventory data. UAV use is particularly appealing in inaccessible and remote locations.

Cyclic steam injection has been used in California since the 1960s. It has been used as a commercial technique to recover oil from diatomite since the mid-1990's. This paper is a synopsis of the analysis and interpretation of over three years of steam injection flow rate, pressure and temperature data from Santa Maria Energy's (SME) cyclic steam injection pilot project in the diatomite zone in the Sisquoc formation on the Careaga Lease in the Orcutt Oil Field, Santa Barbara County, California. The pilot consists of 19 cyclic steam injection wells configured in a 4x5 matrix spaced about 120 feet apart producing from a depth of about 925 feet. Operating practices are used specific to Careaga Lease geologic and reservoir features that include a tailored range of steam injection rates and steam volumes for each steam injection cycle. Comprehensive surveillance and steam injection management protocols are in place for maintaining a safe and reliable operation. The discussion that follows examines data gathered automatically at each well and their real time analyses. Cycle-by-cycle analyses of steam injection and soak periods for all SME wells show (a) no indication of fractures being induced and (b) that large skin effects are present during steam injection in this project. The latter calls into question use of the tubing wellhead pressure as an indicator of the reservoir pressure while injecting steam. Based on the analysis and interpretation of the data, it appears that mechanisms, such as differential thermal expansion of the heated rock and its fluids, are likely to be occurring within the geologic setting of this project to an extent not seen in more permeable rocks and could be favorably affecting the overall production response. Other possible effects are also cited.

Heat is an important component in heavy oil production. One method includes generation of electric current using solar panels or other methods and converting electricity into heat for surface or downhole applications via an electric cable. The heat can help removal of paraffin, wax or hydrate in the production tubing, removal of heat sensitive skins in and around perforations and reduction of oil viscosity in the reservoir zone. The objectives of this study are to present the results obtained from a finite element model study including the cable, well, and the reservoir. Reported results are in continuation of our previous study reported in SPE-185736-MS in 2017. The study uses a commercial finite element model. The model consists of the production tubing, cable, well and the porous media as the reservoir zone. The wellbore fluid is different gases or mostly water. The cable is attached to the production tubing's sides and immersed in well fluid in different lengths. The model solves the two-dimensional heat of conduction equation providing same temperature distributions obtained from other analytical methods. Following parameters are changed using a fixed cable heat density, W/m: well fluids, length of cable immersed, cable orientation, cable lengths, reservoir thermal conductivity and reservoir porosity. The finite element model runs are obtained for vertical well at different model mesh sizes. The best results were reported. In case of stagnant gas surrounding the electric cable, the sand face of the well heats up very quickly. However, transfer of heat up to many meters into the reservoir continues at a slower pace. Similar results are obtained for both vertical as well as horizontal wells. Thermal conductivity of the porous media and its specific heat and density plays an important role in heat transfer and distribution in the reservoir zone. If water is surrounding the cable and given its thermodynamic states of pressure and temperature is allowed to reach near boiling, the heat transfer to the reservoir naturally can be accelerated due to initiation of latent heat of vaporization and its transfer to the reservoir. This study will present all the new finite element runs obtained and the temperature distributions as a function of time and radial distances into the reservoir. Heat is always needed in production of heavy oils worldwide and specifically in California as steam injection faces its own operational challenges. The technology of electric heating needs to be understood and cables needed to be designed properly and effectively. If that happens many deeper and larger heavy oil zones can be produced more economically. Like other similar studies, this study will help design evolution needed for more rugged and robust and effective downhole heaters.

A four foot long pipe (ID 2") packed with silica sand was used to study the effects of formation damage caused by completion and work-over fluids in a high permeability reservoir. Pressures were recorded at five locations (1 foot apart) across the high permeability sand pack as different fluids at a permeability sand pack as different fluids at a rate of 5 ft/day were injected into it. Bentonite and salt concentration of the injected fluids were changed and their effects on the single phase permeability of the sand pack at different permeability of the sand pack at different filtration levels were investigated. Some runs were performed using field water from San Ardo field in California. Finally, effects of formation damage on oil recovery by water-flooding were also studied. Results show that depending on the composition and the amount of the injected fluids, high permeability sand pack develops irreversible permeability sand pack develops irreversible permeability loss which in turn limits the permeability loss which in turn limits the ultimate oil recovery during water-flooding. Results also show that maintaining proper filtration level can minimize the degree of damage to the high permeability sand pack. Introduction: Although many works have been conducted in the past on the mechanisms and consequences of formation damage, high-permeability unconsolidated reservoirs did not receive a fair share of that attention. Recently, Meloy et al. reported on particle movement in capillary network through computer simulation. It is commonly believed, in the field, that these reservoirs can hold up very well against any solids invasion and plugging. It is true that these formations are more forgiving, however, the injection of fluids contaminated with oil and suspended solids can alter both the absolute and relative permeabilities of the porous media and adversely affect oil recovery. In this study, simulated completion fluids and actual lease water samples were used to determine their formation damage potential in unconsolidated sands with 2.6 to 6 darcies. Invasions of suspended solids and oil emulsions and the extent of damage were recorded at different depths. Relative oil-water permeability ratios and oil recovery of damaged and undamaged sand packs were evaluated. Filtration levels necessary to prevent permeability impairment were also assessed. permeability impairment were also assessed. P. 523

Cyclic steam stimulation (CSS) has been used in California since the 1960s. It has been used as an effective method for commercial oil recovery from the very low permeability diatomite formation since about the mid-1990's. Santa Maria Energy (SME) operates a CSS project in the Opal A diatomite of the Sisquoc formation on the Careaga Lease in the Orcutt Oil Field in Santa Barbara County, California. A 19-well CSS pilot has been operational since October, 2009. SME has received entitlement to proceed with an expansion consisting of 110 additional new wells. The CSS process designed by SME for the diatomite zone is one that works without fracturing the reservoir rock. An earlier paper was presented that describes techniques used for monitoring steam injection to help keep the injected steam confined to the zone of interest1. One such technique is Hall's method2 for water injection and adopted for steam. Corresponding algorithms have been programmed into a supervisory control and data acquisition (SCADA) system to survey and analyze all steam injection cycles for all wells. The method has also been used to analyze steam injection step rate tests (SRT). This paper discusses: Two SRT's performed using steam injection; The analytical techniques used; and The results. Of special importance is that matrix flow is seen for CSS even though the injection bottom-hole pressure exceeds that which might normally be considered the rock fracture or parting pressure. This is due to partial plugging and other phenomena during steam injection that occurs to an extent not realized in more permeable rocks (such as very high permeability sandstones). These effects produce extra pressure drop during steam injection into the diatomite zone. This raises questions about the misuse of tubing wellhead pressure readings during steam injection as a reliable indicator of the reservoir formation parting pressure. As a result of this and other work, SME has adopted a specific range of CSS injection rates that are below a critical rate to help insure steam injection is confined to the zone of interest.