Water flooding is the hinge pin for Petrobel Oil Field. Water injection is supplied from shallow water supply wells. Compatibility tests, Petrographic Techniquesand quantitative calculations of scale tendency using specific softwarehad indicated probable deposition of calcium sulphate scale in the near-wellbore (Critical Matrix). Calcium sulphate scale, paraffin & was have been recognized to be a major operational problem. The bad consequences of scale formation& organic deposits comprised the contribution to flow restriction thus resulting in oil and gas production decrease. The nature of calcium sulphate scale is very hard and can't be dissolved with known dissolver. Sister companies that has similar problem were always going to the mechanical remover options which usually lead to further formation damage when invasion of formation rock by small particle sizes of the scale components.Extensive lab and field work was conducted to determine the suitable chemicals to dissolve calcium sulphate scale.The Production of Sidri formation which is currently contained 23 % of belayim land field OOIP (original oil in place) and currently contributes 27 % to the total oil production has been stopped dramatically in some wells.Sidri formation exhibits a high degree of permeability, heterogeneity and increase water injection was done in some areas that lead to increase the possibility of forming scale, most of scale in Belayim onshore is calcium sulphate.Precipitation of mixed organic/inorganic deposits (Calcium Sulfate Scale) resulted in decreasing the permeability in the critical matrix and perforation tunnels. Scale formed in the near-wellbore reduces oil production by blocking the narrow pore throats of the matrix itself This paper highlights Petrobel first application by using the new innovation product SCSR in Belayim land field (Sidri formation), its success and results based on extensive lab studies, SCSR was tested and applied through an effective treatment strategy proposed to remove the scale efficiently; the program was designed taking into consideration the nature of the scale. Furthermore the proposed treatments were conducted and placed using coiled tubing (CT).

Iron sulfide scale is a significant problem in the oil and gas industry whereas the iron sulfide deposition has an adverse impact to the production operations. The scale is present in various species with different iron to sulfur ratios. Iron sulfide species with high iron content is soluble in acids, whereas those rich in sulfur are almost insoluble in acids. East ZEIT oil wells have been produced for 20 years in Egypt. Scales with iron sulfides as the major components form in nearly every producing well. These scales have minor compositional but form at differing rates and thicknesses in the lower half of tubing string. Well East ZEIT-13 was completed initially in Nubia formation which is communicated with another formation called ‘’Lower Senonian’, whereas the drive mechanism is active water-drive. The formation is sandstone with the following specs: Lose, pale yellow, quartz, very fine to fine-grained, sub-rounded to rounded, and moderately sorted sand grains. The reservoir temperature is 300°F. The well was producing using a jet pump (JP), the production stopped due to scale formation. A workover started to replace the completion. The JP was used again to produce the well with very low productivity; +/-0.06 bbl/psi. The power fluid of the JP is oil with 1% water cut. The scale was expected to cover all the casing area below the tubing end until PBTD. A scale sample was obtained and analysis of the scale through XRD showed that the scale composition is as follows; 36% Marcasite (FeS2), 21% Greigite (Fe3S4), 17% Pyrite (FeS2) and 26% Siderite (FeCO3). Both pyrite and marcasite have a very low solubility in HCl, and the only available method of removal in the oil industry is milling. The milling operation failed to solve the problem, therefore, the production was stopped until finding an alternative solution. An effective treatment strategy proposed to remove the scale efficiently; the technical proposal was designed taking into consideration the complicated nature of the scale. Furthermore, the proposed treatments were conducted and placed using coiled tubing (CT). The first application using the SCSR-02 solution has been successfully carried out and the job results were outstanding. Production has been returned with an increment of 50% above its original rate. The well is producing natural flow without using the JP, and efficient cost/Bbl.