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A series of Ni-Mo/Al 2 O 3 catalysts for the hydrotreating of deasphalted vacuum bottoms has been investigated as fresh catalysts and after aging in an industrial reactor during a typical commercial run. Several structural parameters have been varied in the catalyst series. In particular, pore size, surface area, active metal loading and pellet size were changed to investigate the role of kinetic and diffusional phenomena present in this process. The samples were placed in different locations along the industrial reactor allowing for a comparative analysis of the different samples under varying environments, since along the reactor, quality, temperature, and H 2 partial pressure continuously change.Fresh and aged samples were analyzed by a variety of techniques, which include atomic adsorption, scanning electron microscopy, X-ray microanalysis, BET, thermogravimetry and temperature-programmed oxidation. In addition, a laboratory trickle-bed reactor was used to compare the catalytic activity of fresh samples with the residual activity retained by the aged samples after the commercial run.These catalysts deactivate by accumulation of metals and, to a lesser extent, coke deposition. These effects are governed by a competition of kinetic and diffusional phenomena. The kinetic phenomena, which involve adsorption and decomposition of metal-bearing compounds are mainly related to the active metal content and overall surface area of the catalyst, while the diffusion of the molecules inside the pellet are controlled by pore size distribution and pellet size. The current contribution shows how this type of comparative study can be used to identify the most appropriate catalyst configuration for a given set of reaction conditions and feedstock quality.

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Tello Field is operated by ECOPETROL S.A. and located in the Upper Magdalena Valley Basin, Colombia. It began production in 1972 and reached a maximum primary rate of 11, 200 BOPD in 1980. A peripheral water injection process started in 1997, reaching a maximum secondary production of 15, 552 BOPD in 2000. From this date, water production has increased due to an unfavorable mobility ratio (M > 3.5) and a high permeability contrast (Dykstra-Parson coefficient: 0.8 - 0.9). The current recovery factor is 22% and water cut is 92%. This paper summarizes from the laboratory to the field evaluation of a successful polymer gel project for controlling water thief zones, implemented as a strategy to reduce the phenomenon of channeling identified between the injection well Te-49 and the producer well Te-46. The design includes laboratory test (fluid – fluid, fluid – rock and cinetic reaction) to determine the right polymer and the necessary polymer and crosslinker concentration to obtain consistency of the gel at the reservoir conditions. Polymer gel injection began in October 2009, reaching 43, 400 bbl of solution injected (13% of channel volume) and being the largest Latinoamerican polymer gel treatment until now. Injection strategy considered a maximal polymer concentration of 7000 ppm and a fixed polymer/crosslinker ratio ranging from 40:1 to control maximum injection pressure. Field results showed an important increase in oil recoveries (oil production up to 300%) and a reduction in water cut (3%). Comparing these results to what is normal obtained with this technology this is one of the most efficient process until now, this is more relevant when taking into account the peripheral condition of the water injection. This work led to design and implement processes for water injection channeling control to improve the efficiency of water injection into other areas of the Tello field and other Colombian fields.

In the last 10 years, shale gas has emerged as an alternative source because of its contribution to oil and gas reserves. Colombia has a high hydrocarbon potential in unconventional shale gas deposits, and this become the main objective of the national oil industry. Currently proven reserves of conventional gas in Colombia are about 6 TCF, while technically recoverable reserves of shale gas according to the US. Energy Information Administration (EIA) studies 1 are about 55 TCF, so successful production of these reservoirs will increase significantly gas reserves in Colombia.Ecopetrol was the first company in Colombia in starting the characterization of unconventional shales through the stratigraphic well La Luna-1 located in the Medium Magdalena Valley, from which 3445 feet of core were recovered in five months between 2011 and 2012.The need for interpretation frameworks in order to understand properties such as rock source quality, mechanical properties and production performance from a diverse range of measurements require a laboratory characterization of rock properties that is an important part of any resource evaluation. This was the challenge for the labs of the Colombian Petroleum Institute, that based in its experience in Conventional reservoir analysis could adopt its skills and methodologies for analyze 2851 rock samples. The work flow includes geochemical analysis for Total Organic Content (TOC), Pyrolysis Rock Eval VI (parameters S1, S2, Tmax) and quantification of gas content (canister). Samples selection for other analysis was based on core Tomography and Spectral Core Gamma. From the same foot of core, the samples were taken for petrographic analysis, quantitative mineralogical analysis by XRD, mineral distribution and microtexture by SEM, geomechanical Analysis (elastic module and the rock strength), basic petrophysical analysis and Mercury Injection Capillary Pressure (MICP). The information obtained was integrated in order to obtain petrographic rock types, hydraulic rock types and identify the most prospective intervals. The coherence in the parameters obtained by different methods demonstrated the sturdiness of quality system and methodologies applied.