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By S. J. Neethling

"Liberation is a key driver in all mineral separation processes as it limits the maximum possible grade for a given recovery. In flotation, this is further complicated by the fact that it is surface exposure of the floatable minerals that determines the ultimate performance. Liberation, grade and surface exposure are commonly quantified using Scanning Electron Microscopy coupled to Energy Dispersive X-ray spectroscopy (SEM/EDX) analysis of polished sections. The intrinsically 2D nature of this technique can result in significant sampling errors and stereological effects that can affect the quantification of the ore’s textural characteristics. X-ray micro-Tomography (XMT) is an imaging method that can non-invasively and non-destructively delineate ore fragments in 3D, thus providing an alternative method that eliminates the need for stereological corrections and readily provides surface exposure. A methodology and automated algorithm were designed for extracting this information from images of closely packed particles, thus allowing samples containing a large number of particles to be assessed.The main drawback of XMT is that, unlike SEM/EDX, it cannot directly measure the mineralogy of the sample, instead producing a 3D X-ray attenuation map. We therefore also present an algorithm for calibrating the thresholding of the XMT images based on SEM/EDX images of sections through the same sample, thus allowing the liberation analysis to be carried out on a 3D mineral map in which the uncertainty in the mineral assignment is small and statistically quantified.The methodology was tested on low grade porphyry copper ore as this is both an industrially relevant and traditionally difficult system to quantify using XMT due to the similarity in the X-ray attenuation of the sulphide species, especially the pyrite and chalcopyrite. As each 3D volume imaged contain 100-1000s of grains, large data sets can be readily produced. By dividing these particles into classes based on both their surface exposure and grade, the extent to which there is preferential breakage of the particles can be assessed—an important consideration if sufficient surface liberation for good flotation performance is to be achieved at coarser particle sizes. It is also shown that erroneous conclusions can be drawn when basing the analysis on 2D sections through the particles."

Jan 1, 2018

There are some problems in the beneficiation of fine-grained oxidized iron mineral such as high cost, severe sliming, poor results and low recovery due to the fine disseminated size of the mineral. Taking several representative types of finely-disseminated oxidized iron minerals as examples, the author analyzed the main difficulties in the beneficiation of such kind of ores and discussed the existing problems in grinding-classification, technological process, flotation reagents and separation equipments and the resolvents of these problems.

Jan 1, 2014

By Chao Li, Kym Runge, Saeed Farrokhpay, Dee Bradshaw

"It is well known that froth phase has a controlling influence on the overall flotation performance. Froth recovery is expected to be affected by froth transportation behaviour. The latter has been represented by different volume balance and energy balance based models. In froth transportation models based on a volume balance, the froth phase is divided into different zones. The total froth residence time is the sum of the time spent in each zone and is dependent on the cell geometry, bubble burst rate and the position that bubbles enter into the froth phase. Alternatively, the froth transportation model based on an energy balance treats the froth phase as a block. In this model, froth height above the concentrate lip is being predicted by minimising the energy of the system which is dependent on the froth geometry, froth stability and froth rheology. The froth height can be used to calculate the froth efficiency of delivering mineralized bubbles from the pulp to the concentrate lip. This paper critically analyses the current models of froth transportation in flotation, and examines the limitations of these models. The importance of froth rheology, which is the resistance to the froth flow towards the discharging weir, in determining froth transportation, is also highlighted."

Jan 1, 2014

By P. Zarate, M. Peart, T. Bhambhani, D. R. Nagaraj

More than 50% of all the molybdenum produced in the world is a by-product of copper production. A bulk Cu-Mo concentrate is first produced, which is subsequently separated into Cu and Mo concentrates. The Cu-Mo separation circuits rely on the use of inorganic Cu sulfide depressants such as NaSH, Na2S, and Nokes, which are hazardous, and sometimes require very large dosages for effective depression. Synthetic polymeric depressants are safer and more efficient, and are now being used on the plant-scale. Data presented in this paper demonstrates that these polymeric depressants can replace 50-90% of all the NaSH in Cu-Mo separation at a fraction of the NaSH dosage. In this paper we provide an overview of the mechanistic and practical aspects of the Cu-Mo separation with inorganic depressants and polymeric depressants. Important practical aspects include depression dynamics (related to conditioning time and rate of depression), optimum pH for effective separation, the role of pH modifiers such as lime and NaOH, and the effect of flotation gas on the efficacy of the separation. Using nitrogen as flotation gas, the NaSH consumption can be reduced by up to 95% by using a small amount of polymeric depressant. The experiments with conditioning time demonstrate that there is a significant rate component to the depression mechanism with NaSH, which is absent for the polymeric depressant system. This has important implications in the effective use and application of the depressant. It is also demonstrated that the pH modifier type (NaOH or Ca(OH)2) has no significant effect on separation efficiency and Mo recovery (i.e. Ca2+ ions do not depress MoS2 in the Cu-Mo separation).

Jan 1, 2014

By M. Evertsson, K. Bhadani, E. Hulthén, M. Bengtsson

"Modelling and simulations for mineral processing plants have been successful in replicating and predicting predefined scenarios of an operating plant. However, there is a need to explore and increase the potential of such simulations to make them attractive for users. One of the tools to increase the attractiveness of the simulations is through applying optimization schemes. Optimization schemes, applied on mineral processing simulations, can identify non-intuitive solutions for a given problem. The problem definition itself is subjective in nature and is dependent on the purpose of the operating plant. The scope of this paper is to demonstrate two optimization schemes: Multi-Objective Optimization (MOO) using a Genetic Algorithm (GA) and Multi-Disciplinary Optimization (MDO) using an Individual Discipline Feasible (IDF) approach. A two stage coarse comminution plant is used as a case plant to demonstrate the applicability of the two optimization schemes. The two schemes are compared based on the problem formulations, types of result and computation time. Results show that the two optimization schemes are suitable in generating solutions to a defined problem and both schemes can be used together to produce complementary results. INTRODUCTION The comminution process for a mineral processing plant consists of multiple crushing and classification stages and aims to produce fine material to liberate ore from the minerals. The modelling and simulation of such processes are well established using static process models (King, 2001; Napier-Munn et al., 1996). A recent development in the dynamic modelling for such processes has shown further increase in fidelity compared to the static process models (Asbjörnsson, 2015). The developed simulations can be utilized to design, operate and control mineral processing plants based on the requirements of users (Bhadani et al., 2017). Typically, the requirements in the operation of the comminution process are conflicting in nature, as for instance, reduction of power draw by process units, maximization of production of fine materials, and increasing utilization of the process units. These conflicting requirements leads to a Multi-Objective Optimization (MOO) problem to operate a mineral processing plant. The MOO problems are normally referred to as non-linear problems and its fundamental understanding with respect to process behaviour is difficult to achieve."

Jan 1, 2018

By Robinson Irarrazabal, Edison Collinao, Rodrigo de Carvalho, Patricio Davila, Marcelo Tavares

"In recent years, DEM (discrete element method) softwares, along with 3D laser measuring equipment, have become powerful tools to describe mill charge behavior, as well as forces acting on the liners of SAG mills. With the aim of contributing to streamline this application of the advanced technologies ME Elecmetal and Universidade Federal do Rio de Janeiro, UFRJ, proposed a new approach to improve the design of mill liners using elements from mechanistic modeling of grinding. The paper presents a methodology for continuous improvement of liner design, which uses information from the DEM collision energy spectra in the mill discriminated for the different components (ore and steel balls), as well as information on the breakage properties of the ore being ground. From these it proposes the concept of "effective collisions", which corresponds to the collisions that are of sufficient magnitude to cause breakage, thus allowing to discriminate from impacts that do not cause breakage either in a first impact or after repeated loading. It also tracks the collision of steel balls against the shell in order to assess their potential damage to the liners. An industrial case study is presented of a 38’ diameter SAG mill, which was experiencing challenges associated to liner breakage and low efficiency with the old liner design. Through a modification of the liner design, simulations demonstrated the potential benefit associated to reduction in ultraprojection and improvement in mill capacity. Implementation of the new design in the SAG mill was carried out, resulting in increase in daily throughput from 6 to 12%. Further, the time spent in liner change was reduced by 47% given the reduction in the numbers of parts. This operation also benefited from having no stops due to unplanned shutdowns to replace broken tiles. These demonstrate the benefit of coupling advanced computational tools to sound engineering principles in continuous improvement of liners."

Jan 1, 2014

By I. Y. Titov, Victor D. Samyguin, A. Y. Nikitin

"It is suggested that improvement of separation process efficiency in machines and circuits of selective flotation should be based on application of the principle of technology individualization (PIT). This principle is grounded on the following provisions.The mineral composition of ores is used to establish the correlation between the selective reagent mode and the individual value of hydrodynamic conditions of flotation machines together with individual structure of the process flow diagram. The individuality of all sorts of particles identified by methods of process mineralogy was characterized by their distribution according to the rate of flotation (or spectrum). The spectrum identification is carried out by modeling and by experimental and computational method on the data obtained on various types of laboratory flotation machines.The computer-aided test is used to determine the optimal fraction distribution, which reaches the highest possible level of concentration data. The direction of hydrodynamic factors action on concentration data is estimated based on comparison of design base and experimental spectrum. The improvement of separation efficiency in devices is achieved in special-purpose flotation machines (SFM) the design of which provides optimization of hydrodynamic regime in spatially isolated zones. It is demonstrated that the main parameter of SFM operating mode individualization is the rise rate of bubbles going from the chamber into the froth. During this time the composition of particles optimum for separation is formed on its surface. Additionally, it is necessary to coordinate in the zones the residence time of pulp and foam streams with the air consumption. The improvement of separation efficiency in flotation process flow diagrams may be achieved by making several cascades with SFM installed in them. The individual effective structure of the scheme for a definite ores material composition depends on the ratio of particle varieties in the spectrum and is revealed by modeling."

Jan 1, 2018

The reactivity of clay minerals and variety of these reactions are greater than any other known colloidal material. While it is acknowledged that clay minerals can cause problems in mineral flotation, the literature contains conflicting evidence, particularly with respect to the effect of clays on froth stability. It is well known that achieving and maintaining optimum froth stability is an influential factor in determining froth flotation performance. However, the presence of clay minerals in the ore is a major challenge to obtaining a stable froth. In fact, clay minerals could reduce froth flotation performance by both decreasing and increasing froth stability. The mechanism by which clay minerals affect froth stability is not fully understood and needs to be investigated further. In order to improve flotation performance, reliable knowledge of the effect of clay minerals on froth stability is essential which is discussed in this paper. Keywords: froth flotation, froth stability, clay, clay minerals

Sep 1, 2012

By R. Els Ellis

Enhanced granulation of UASB granules was tested on pilot scale with two different test reactors (about 5 litres capacity each). Sludge from a local sewage works was used, with peach cannery effluent as carbon source. Cyclic motion of the reactor contents, and a daily replenishment of feed material create the necessary stress conditions for enhanced growth. Sizable granules, bigger than 0.5 mm, were produced within 20 days. Of the two reactors tested, the reactor equipped with a horizontal agitation shaft proved more effective.

Jan 1, 2003

By Reuter M. A., R. D. van der Weijden, W. F. C. van Wageningen

"Copper(II) can be recovered or removed from acidic copper sulfate solutions as cuprite or metallic copper powder by reduction with carbohydrates. The copper powder characteristics, such as size and shape of particles, determine the tendency to adhere to reactor walls and to agglomerate. In order to make this process suitable for a commercial scale pipe reactor, process conditions and the reactor configuration were varied in order to influence the copper characteristics in a positive way. The aim was to achieve proper particle throughput in the pipe reactor and to obtain a well defined copper powder.In this paper the effect of both, chemical and physical parameters on the shape and size of particles were systematically studied in a number of autoclave experiments. These parameters include mixing, Cu(II) concentration, pH, temperature, seeding, use of additives and reactor materials. Additionally, Monte Carlo simulations of copper growth inside a Kenics static mixer were made. Results show that the use of additives and the use of static mixers influence particle characteristics the most."

Jan 1, 2003

By Cheng Gan, Gui Xiahui, Li Shulei, Cao Yijun, Liu Jiongtian, Wu Lun

Flotation rate constant is an essential parameter in the flotation process. The fine coal sample utilized in this investigation is anthracite from the Shenhuo mine in eastern China. Fine coal flotation rate tests were conducted to compare the flotation rate constant at constant power input with that at gradually increasing power input. Results indicate that the flotation rate constant decreases with the flotation process and increases as the flotation energy is increased. In addition, the flotation rate constant is close to the maximum value. The increasing trend of the flotation rate constant gradually slows down as the flotation energy input increases.

Jan 1, 2014

By Venkata S. Buddhiraju

Pelletization of iron ores involves balling on a rotating disc to produce wet pellets and induration of wet pellets on a moving grate to produce fired pellets. The quality of pellets produced and the productivity of the pelletization process depend strongly on the characteristics of the feed to the pelletization disc, especially the particle size distribution and the moisture content. The upstream processes involved in the preparation of pelletization feed include grinding, thickening and filtration of the iron ore slurry. The focus of the present work is the closed circuit wet grinding of iron ores. The circuit consists of a primary ball mill, a regrind mill and a hydrocyclone. A population balance model was developed to predict the grinding kinetics and an empirical model was fitted for the separation of fine particles from the coarse particles in the hydrocyclone. Batch grinding kinetics experiments were performed on a laboratory scale ball mill to obtain the ore breakage parameters which were subsequently used for the simulation of the industrial mills. The models were customized for the industrial operations and the effects of different process variables like feed flow rate, water flow rate, etc., on the size distribution of product from the grinding circuit were studied. Additionally, different circuit configurations were simulated to determine operating conditions that could result in the desirable product particle size distribution. The results of simulation were in close agreement with plant observations and the new circuits explored through simulation have helped in identifying potential opportunities for process optimization and control

Sep 1, 2012

By Williams Calderon, César Arredondo, Gonzalo Montes-Atenas

The quality of final concentrate in froth flotation circuits is largely dictated by the correct implementation of the froth washing operation in flotation cleaning stages, which are commonly installed in column flotation cells. In flotation plants, this aspect has been largely overlooked and the froth washing is restricted to the use of perforated piping through which process water flows producing a similar effect to that observed in "fountains": jet created with low energy crosses the froth phase washing out entrained particles as well as particles weakly attached to bubbles. The aim of this research study is to assess the efficiency of traditional froth washing systems theoretically and experimentally. A theoretical model was implemented using Fluent® software where a jet of variable speed was introduced in a continuous soft matter phase with physical properties similar to those observed in a froth phase in wet and dry conditions. In addition, a simple experimental protocol was designed to validate the model. It was found that the water process jet-like flow influences the behavior of 2 to 3 times the equivalent volume in the froth phase. Such influence zone is dramatically reduced as the froth phase becomes drier. These results were confirmed by the experimental findings indicating that a better froth washing technologies must be assessed and implemented. Some aspects of the ideal froth washing system are derived and discussed in details.

Jan 1, 2014

By Anuttam Patra, Romain Bordes, Andreas Fredriksson, Tommy Karlkvist, Krister Holmberg, Kota Hanumantha Rao

Almost all of the flotation reagents used today were discovered by continued application of empirical methods and/or trial and error experimentation. Moreover, with the metal-ion specific approach used so far, it is difficult to separate the minerals containing the same constituent metal ion. A critical assessment of molecular recognition processes involved in biomineralization suggested the possibility of using reagents which are surface specific. The concept that the molecules consisting of two or more functional groups having appropriate spacing between those so as to achieve structural/stereochemical compatibility during interaction with the mineral surface exhibit structure-specificity is thought to be extended to the design of specific collectors in flotation processes. In the present study, for the first time, a rational design of surface active molecules, and thereby the recognition of crystal faces (of minerals) by these molecules through structural and stereochemical matching is being utilized successfully to selectively float various minerals. For this purpose, carboxylate-based collectors (for mineral specific flotation of calcium minerals) as well as xanthate-based collectors (for mineral specific flotation of sulphide minerals) with a fixed alkyl chain length but having two functional groups with varying geometrical distances (separated by a spacer of one, two and three carbon atoms) between them have been synthesized. In this article, we have discussed the design, synthesis, purification of these novel mineral specific collectors as well as their important solution parameters in relation to flotation processes.

Jan 1, 2014

By Bert Huls

Already starting, new drivers will dictate how future mineral processing plants will be designed and operated. These drivers include requirements in water and energy conservation because of rising costs, larger demand for mineral and metal products as the result of a rising population, and the increasing demand from the population in general to have influence over what type of operations will be developed where. Mineral operating facilities will require processing of lower grades. To do this economically, design engineers will be influenced to introduce newer concepts, or return to older processing concepts once deemed not desirable. Our understanding of the fundamentals must be improved, and this may come from better measurement techniques and more process piloting, and will go in hand with a reduction of waste generated during the process, improved separation of minerals or product size. Process engineers will also be required to not just design according to the established 3D methodology for efficient plant installation. Already in other industries the design concept encompasses the entire range from source to product. Not only that, the design will be affected by public influence that must be illustrated prior to project execution. On the one hand, the added dimension in design may slow a project; on the other hand it may result in a blessing, and in a higher responsibility for engineering.

Jan 1, 2014

By Hideki Yamamoto, Norihiro Murayama, Junji Shibata

"Hydrothermal syntheses of zeolite from coal fly ash were carried out by using various alkali sources. NaOH, Na2CO3, KOH, K2CO3 and their mixture were applied for an alkali source of zeolite synthesis. The various physical properties of the reaction product, such as the kind of zeolite crystal, cation exchange property, surface texture and so on, was investigated through the zeolitization reaction from fly ash. The mechanism of zeolitization reaction was considered from these results.Zeolite P(NaP), hydroxysodalite(HS) and chabazite(K-CHA) are synthesized as zeolite species, when fly ash hydrothermally reacts in various alkali solutions at 393K. The crystal structure of the products obtained in NaOH solutions for 3h changes from NaP to HS with increasing NaOH concentration. K-CHA formation in KOH solutions needs 10h of reaction time, which is longer than that of NaP or HS.Dissolution, condensation and crystallization steps exist in the zeolitization reaction from fly ash, and the particle surface of products remarkably changes in each step. The fly ash is spherical particles and the surface is smooth(Fig.1(a)). The dissolution of fly ash occurs in the heating process until 393K, and the particle surface changes like unevenness(Fig.1(b)). In case of NaP, the condensation of aluminosilicate ions takes place at 373-393K, and the amorphous aluminosilicate is deposit on the unreacted fly ash(Fig.1(c)). The crystallization of NaP already begins to occur at 393K and the surface is covered with fine zeolite crystals for 24h(Fig.1(d))."

Jan 1, 2003

By Douglas Fuerstenau

"Comminution not only is the major energy cost in mineral processing but it also can limit the grade of ores that can economically be processed. Rittinger first postulated that the energy for comminution is proportional to the new surface produced. Because most of the strain energy needed to initiate and propagate cracks in particles cannot be recovered, researchers reported woefully low comminution efficiencies. Recognizing this, Schoenert proposed that the baseline for assessing comminution efficiency should be the mechanical energy needed to break single particles. After extensive single-particle studies, Schoenert turned to comminuting beds of particle in piston dies. Finding particle-bed comminution to be energy efficient, he had the brilliant conception of making the process continuous, namely his invention of the choke-fed high-pressure roll mill (HPGR). Practical comminution involves masses of particles, which can lead to energy efficiencies far less than that of single-particle breakage. A three-way classification of grinding modes in terms of the mobility of the particle mass provides the necessary insight into the low efficiency of different comminution machines: namely, single-particle breakage, confined particle-bed grinding (HPGR), and loose-bed grinding (ball mill). Examples are given for determining and comparing comminution efficiencies. The size distribution of comminuted products become self-similar, and a single parameter, the median size, can be used to quantify the extent of comminution. The reduction ratio, expressed in terms of the mean size of the feed and product, varies linearly with expended energy and the slope of such plots is a measure of the grindability of the mineral. This approach clearly gives the order of energy efficiency as single-particle > particle-bed > loose-bed comminution. HPGRs are more efficient at low reduction ratios but lose that advantage at higher reduction ratios. Extensive hybrid grinding experiments carried out with our instrumented ball mill and HPGR showed significant energy savings by first comminuting the material in the HPGR and followed by the ball mill. At Cerro Verde an industrial-scale hybrid HPGR/ball mill system is reported to have a 13 percent energy savings over a SAG mill/ball mill system."

Jan 1, 2014

By David I. Verrelli, Boris Albijanic

"Froth flotation is an exceedingly complex physicochemical process. The convenience of distilling much of the complexity of the bubble-particle interactions into a single parameter has led to the continuing popularity of the classical ‘induction time’ to quantify the threshold for bubble-particle attachment to occur. Despite this popularity and the simplicity of the concept, there is no single universal method of evaluating the induction period. In this paper, we begin with a critical review of the available techniques for estimating the induction period. These are: back-calculation from experimental (micro) flotation tests; pushing a particle toward a stationary bubble (or vice versa) using an atomic force microscope (AFM); pushing a bubble toward a stationary bed of particles in the ‘Induction Timer’; pushing a bubble toward a stationary solid surface using the ‘integrated thin film drainage apparatus’ (ITFDA); and dropping particles onto a submerged stationary bubble using the ‘Milli-Timer’ device. Each one of these methods has advantages and disadvantages, and the best choice depends on the application. In the experimental section, we present quantitative comparison of the induction periods estimated using two different techniques, namely the Induction Timer and the Milli-Timer. The same particles were tested in each device, under the same conditions. It was found that by tuning the operation of the particle pick-up device, similar estimates of induction period could be obtained to the estimates made by direct observation with the Milli-Timer. In the former device a bubble is driven toward a particle bed at a controlled rate, whereas in the latter a particle’s motion is governed by the hydrodynamics. The potential to match these presents an intriguing prospect for better understanding the bubble-particle interaction, and the possibility to ‘calibrate’ the simpler Induction Timer against direct observations."

Jan 1, 2014

By Andrzej Luszczkiewicz, Alicja Bakalarz

The application of new collectors is considered to improve the beneficiation of Polish sedimentary complex copper ores from the Legnica-Glogow Copper Basin (SW Poland), the upgradeability of which becomes more difficult because of ores grade declining. One group of potential collectors is represented by nonpolar reagents. According to the available literature data, only selected sulfides float in the presence of the nonpolar liquids. The paper presents laboratory scale flotation results for the main sulfide minerals occurring in the Polish copper ores applying either thiol (potassium ethyl xanthate) or nonpolar (aqueous emulsion of n-dodecane) collectors. The investigated feed contained 1.91 % Cu in the form of sulfide minerals such as bornite, chalcopyrite, chalcocite and covellite. Other sulfide minerals including galena, pyrite and sphalerite were also present in the samples. Several flotation tests with various doses of each collector were conducted. Mineralogical analyses of flotation products were carried out and the results compared. A comparison of the results indicated that all sulfide minerals floated well with high recoveries ranging from 91 % to 99 % in the presence of the thiol collector. The use of the nonpolar collector provided results in flotation of sulfide minerals with different terminal recoveries from 61 % for chalcopyrite to 100 % for sphalerite. The most significant differences in flotation in the presence of both types of collector under various conditions of upgrading were observed for chalcocite, chalcopyrite and covellite. Similar flotation results were observed for sphalerite and galena for both collectors. The studies confirmed selective flotation of sulfides from the copper sulfide ores of the Legnica-Glogow Copper Basin in the presence of nonpolar collectors.

Jan 1, 2014

By Joseph Kelly, Christopher Kelsey

This revolutionary super-fine crusher has the unique capacity to generate fine and ultra-fine products from single stage reductions of coarse or fine mineral feeds. The crusher consists of a rotating compression chamber and an internal gyrating mandrel. The axis of rotation of the shell is displaced relative to the axis of the vertically mounted mandrel. The inner surface of the compression chamber is machined as double cone frustums at an angle equal to the displacement angle. Crusher feed is accelerated into a compacted particle bed, which lines the inside of the compression chamber. The depth of the compacted bed progressively increases until the mandrel is engaged. The mandrel is then free to rotate with the compression chamber. Continued feeding increases power draw and triggers the counter rotating mandrel gyration drive. The gyrating mandrel delivers multiple compressions at high pressure to the rotating particle bed. High concentrations of energy are harnessed within a small active volume over short retention times. The combination of extraordinarily high power intensity and extreme compressive force results in primary compressive fracture and induced secondary tensile failure. The axially displaced rotation of the compression chamber effectively distributes the breakage forces throughout the particle bed. This paper covers open circuit, pilot trials on magnetite, perlite, garnet, marble and a copper/pyrite concentrate. Particular emphasis is placed on the extraordinary results achieved with trials on zircon and highly refractory fly ash. The extreme duties were deliberately chosen to demonstrate the crusher’s application scope and potential to impact capital operating and maintenance costs as the technology matures. Super-fine crushing, once considered impracticable has the potential to offer compelling options for the generation of ultra-fine products.

Jan 1, 2014