The Optimal Formula for Organic Oil Immobilization in Algerian Petroleum Drill Cuttings Using Solidification/Stabilisation Treatment

Hassi Messaoud oil field is one of the most important fields in Algeria and the world, because it covers an important quantity of total Crude Oil Production in Algeria. Furthermore, two-thirds of this oil field is underexplored or not explored. Therefore, the drilling process of petroleum wells in this field is a continuous process that results in significant drilling waste. This implies that, enormous noxious quantities of drilling waste are produced daily that require treatment via solidification/stabilization (S/S) process before being landfilled. These types of wastes have pollution concentration that significantly exceeds the safety standards. In this study, we focus on the factors affecting the solidification/stabilization treatment of the drill cuttings obtained from Hassi Messaoud oil field and the process optimization. The solidification/stabilization is performed using the cement as binder, sand, silicate, organophilic clay and activated carbon as additives. The study is divided in two steps: (i) aims to determine the optimum ratio of each element used in the S/S process for the organic element (hydrocarbon) elimination, (ii) aims to combine the optimum ratios found in the previous step to determine the optimal mixture. The obtained results in the first step showed that the optimum ratio for the cement-to-drill cuttings mass ratio is 0.09:1. For the additives-to-drill cuttings mass ratio are 0.04:1, 0.006:1, 0.013:1 and 0.013:1 for the sand, sodium silicate, Organophilic clay and activated carbon, respectively. An optimum formula is found which its main finding shows that the hydrocarbon content of our sample is dropped from 9.40 to 1.999%. Many tests results before landfilling were investigated such as matrix permeability, resistance to free compression and heavy metals rate before and after S/S process. Besides that, in the light of outcomes achieved by this assessment these harmful cuttings can be converted into a useful product that helps in reducing the environmental foot prints.

Technology Placement of Drilling Waste Storage with the Use of Soil Cement Screens

The authors of the article analyze the known technological solutions for the disposal of waste from drilling wells. The authors propose a technological solution for the arrangement of drilling waste storage from soil-cement elements with the installation of soil-cement coating. Filling the storage facility with waste is proposed to be carried out with layers of drilling mud, soil, ash. Used a layer of fly ash to reduce humidity, if it differs from the optimum. The thickness of the layers was chosen based on ensuring optimal humidity. The authors propose to add ash from the Mykolayiv thermal power plant in the amount of 5 wt.% By weight of cement when installing the walls and covering the sludge storage from soil cement. It is established that with increasing the shelf life of samples in water up to 180 days, the average compressive strength of soil cement samples increases. If we compare without additives and with the addition of the appropriate percentage of removal ash, the value of strength increases by 12-15%.

PRODUCTION OF SEEDLINGS OF COLUBRINA GLANDULOSA PERKINS WITH DRILLING WASTE FROM OIL WELLS AND MYCORRHIZAL INOCULATION

Oil exploration, whether onshore or offshore, results in residues from the drilling of wells, called gravel. The use of this environmental liability in the production of seedlings for forest restoration could contribute to an appropriate destination for this waste. In the present study, the objective was to evaluate the effect of the substrate formulated with gravel, with and without inoculation with arbuscular mycorrhizal fungi (AMF), on the growth and nutritional status of seedlings of Colubrina glandulosa. The design used was completely randomized in a 5x2 factorial scheme, with five gravel doses (0, 5, 10, 15, and 20%), with and without inoculation with a mixture of AMF spores (Gigaspora margarita¸ Rhizophagus clarus, and Dentiscutata heterogama) with six repetitions, totaling 60 experimental units. Height (H) and stem diameter (SD) were evaluated at 30, 60, 90, and 120 days after seedling transplantation, when the plants were sectioned in shoots (branches + leaves) and roots, to determine dry biomass of shoots (DMS) and of roots (DMR), leaf area index (LAI), rate of length of fine roots colonized by AMF (COL), and chemical composition. The substrate obtained with the application of the lowest gravel dose (5%), without the mycorrhizal inoculation, provided significant increments in H, SD, LAI, DMS, DMR, and COL of the seedlings of Colubrina glandulosa, when compared to the other gravel doses and the presence of mycorrhizal inoculation, 120 days after seedling transplantation.

Technologies for Safe Handling of Drilling Waste during Well Construction in the Ob Bay

Development of the Russian oil and gas fields in the Arctic requires ensuring industrial and environmental safety of conduct of the operations. Large and unique oil and gas condensate fields are discovered in the southern part of the Kara Sea. The Kamennomysskoye-Sea, Severo-Kamennomysskoye, Semakovskoye, Parusovoye, etc. gas condensate fields are located in the Ob Bay of the Kara Sea. The raw material base of the Severo-Obskoye gas condensate field, unique in terms of the reserves, will become the basis for future Arctic LNG projects. Based on the published data, the initial recoverable total hydrocarbon resources in the Ob and Taz bays are about seven billion tons. Active exploration and commissioning of the already discovered fields require the large volumes of well drilling in a freezing sea, the presence of permafrost, and gas hydrates. During construction of the wells and operation of the offshore ice-resistant oil and gas production platforms, it is required to ensure the disposal of drilling waste (cuttings) and domestic water. There are two technologies for waste disposal — injection into the reservoir or into the clay formations. The first one is used in onshore fields, the second one — on the shelf. Injection into a clay reservoir is successfully used in the Lunskoye gas field on the shelf of the Sakhalin island, and on the Prirazlomnoye oil field in the Pechora Sea. The possibility of using the method and the selection of a reservoir for injecting waste into it requires a geological justification, and the reservoir should ensure a stable injectivity of the required volume. The article presents the results of modeling the injection into the formation of drilling waste, and the waste of the household activities for the Kamennomysskoe-Sea gas condensate field. Calculation was made concerning the zone of absorption of the technological waste into the designed well of the offshore ice-resistant stationary platform. Formation allocation for waste injection was made according to the data of a complex of offshore wells geophysical studies. Three packs of sandy-argillaceous rocks with high reservoir properties were selected as the object of industrial waste disposal. Сalculation was carried out related to the radius of the spread of waste (effluent) in the target reservoir considering drilling and operation of twenty five wells, the construction of which is planned for five years. The results of modeling the process of pumping industrial waste of various types into an absorption well showed that the planned volumes can be successfully disposed of in the selected objects. This will allow to ensure functioning of the marine industry and its environmental safety.