Estudo do efeito da lignina em emulsões água em óleo de petróleo pesado

• Autor(a) principal: Silva, Mayara da
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/10772
• topic: Emulsion; Heavy oil; Stability; Homogeneity; Lignin; Emulsão; Petróleo pesado; Estabilidade; Homogeneidade; Lignina; Química; 54

Water-in-oil (W/O) oil emulsions are present from well drilling to refining and cause various problems. Heavy oils have higher amounts of polar compounds than light petroleum and this causes the formation of emulsions with high stability. Such emulsions need to be dehydrated to reduce the impacts generated. Thus, studying and evaluating the factors that affect the stability of an emulsion is important for the oil industry. Due to the lack of information on the evaluation of the behavior of W/O emulsions by the addition of natural products, in this work a study was carried out on the effect of lignin addition on W/Oemulsions of a heavy oil (gravity of13.7) with asphaltene content 7wt% and 32wt%resins. Initially, to check the droplet size distribution (DSD), select the ideal mechanical rotationand the influence of the electrolyte type on the stability, emulsions were prepared by adding volumes of 10, 20, 30, 35 and 40% w/v of two types of water (deionized and formed) under mechanical stirring at 2500, 5000, 10000 and 15000 rpm and a saturated NaCl solution added to the oil at the rates of 10, 20 and 30% w/v homogenized in the rotation of 5000 rpm. When the best working conditions (5000 rpm) were chosen and due to the natural occurrence of formation of W/O emulsions with formation water in the oil exploration process, the preparation of the emulsions for testing with natural product consisted of the homogenization of the oil with water of formation and addition of alkaline lignin solution in nature at the concentration of 0.5 and 3% w/v. Formationand lignin water contents totaled the volumes of 10 and 30% w/v of aqueous phase in the emulsions. In addition, W/O emulsions were prepared with water of formation and addition of solutions of modified lignin and saponin, in the concentrations of 0.5 and 3%w/vthey use the emulsions prepared with in natura lignin.The factors evaluated were aging, temperature, water content, drop size, salt concentration and added natural product. Theresults showed that the emulsions formed with deionized water, formation water (5.5·104mg·L-1of NaCl) and saturated NaCl solution (2.7·105mg·L-1) showed stability even after aging for 30 daysand when subjected to heating. The emulsions prepared with formation water had a higher DSD value than those prepared with saturatedNaCl solution and deionized water, respectively. This distinction between droplet sizes can be related to the presence of different charge ions in the formation water. The results for the emulsions prepared with addition of natural products showed that the in natura and modified lignin behaved as a good emulsifying agent when added in low concentration and quantity. The saponin presented as a good emulsifier under the established experimental conditions. The main component analysis of the infrared spectra data showed that only emulsions prepared with 30% w/v aqueous phase of water formation and addition of saponin presented different behavior than the other emulsions evaluated. This suggests that the emulsions prepared with deionized water, formation water and lignin addition (in natura and modified) did not change the chemical profile of the studied oil