Actual Production Conditions Research Articles

Provision of property and cold strength uniformity with the falling weight test in coiled and sheet rolled product of steel Kh70 from a 2000 mill

A metallurgical basis is developed for providing a high set of properties of coiled rolled product, including with the falling weight test (FWT), on the basis of retaining the developed condition of austenite after controlled rolling applied to actual production conditions in a 2000 mill, including with small rolling ratios. In CherMK Severstal production has been successfully proven for coiled and sheet rolled product of steel Kh70 16 mm thick with a property guarantee with the FWT.

Inhibitor Performance on Corrosion and Erosion/Corrosion Under Turbulent Flow With Sand and CO2—An AC Impedance Study

Summary Erosion/corrosion is a severe problem in oil and gas producing wells because of high flow velocity and sand particles entrained in the system. Using corrosion inhibitors to reduce erosion/corrosion has recently been proposed as an economically viable solution for carbon-steel piping systems (Smart 1991). In the literature, most studies using inhibitors to mitigate corrosion have been conducted under stagnant or low flow rate (<1 m/s) conditions. However, severe erosion/corrosion may occur when inhibitor films are removed from the steel by high liquid shear forces under actual oil and gas production conditions. The inhibiting effect of a commercial inhibitor [named Inhibitor A (Wang et al. 2005)] on the behavior of carbon steel in CO2-saturated media has been examined under high flow velocity with sand by electrochemical and gravimetric measurements. Experiments were performed using a Rotating Cylinder Electrode (RCE). The alternate current (AC) impedance technique was used to study the effect of inhibitor adsorption onto the metal surface. The study clearly reveals that the addition of the inhibitor moves the corrosion potential toward positive values and reduces the corrosion rate. Changes in impedance parameters (Rct and Cdl) are indicative of adsorption of inhibitor on the metal surface leading to the formation of protective films.

Determination of the forming tool load in plastic shaping of a round tube into a square tubular section

The forming tool load in plastic shaping of a round tube into a square tubular section has been determined analytically and also numerically by applying finite element simulation. The theoretical results were compared to experimental measurements obtained in testing tube specimens using a specially designed test-rig simulating actual production conditions. The comparison has shown that the results obtained analytically were in fair agreement with those obtained experimentally, while the finite element simulation results were in agreement only at small deformation. The shaping load–displacement relationship obtained analytically was applied to predict the roll load and drawing force in drawing a round tube into a square tubular section through a head comprising four idle flat rolls. The results obtained from this application proved to be in fair agreement with those obtained from a previous more elaborate solution, which recommends the use of the analytical relationship, obtained to direct industrial application.

Calculation of thermal stress affecting strip flatness change during run-out table cooling in hot steel strip rolling

To fulfill further reducing production costs at the meantime enhancing product quality is always one of the objectives pursued by steel enterprises and researches. With increasing demand on higher quality of hot rolled strip shape, strip flatness change developed during cooling on the run-out table has received significant attention and should be considered in online strip shape control model. Non-uniformity of transverse temperature distribution in strip is the ultimate reason for the occurring of strip flatness defect after hot rolled flat strip is cooled to room temperature. Based on the large amount of thermal image field measurements on strip surface, transverse temperature distribution rules of strip were concluded. A FE model was established to analyze the thermal stresses developed during the cooling of hot rolled strip on the run-out table using finite element program ABAQUS. Analysis results demonstrate that temperature drop within strip edge region will make strip flatness develop to the trend of edge wave and are verified by the actual strip flatness observation on skin pass rolling line. This viewpoint agrees well with the actual production condition. One compensation control strategy, named slight center wave rolling, is proposed based on the FE analysis work. The main idea is that steel strip is rolled with slight center wave at the exit of the last stand of finishing mill to compensate the flatness change trend of edge wave during the cooling.

Agro-energie in Basilicata : un approccio analitico per la valutazione dei costi di trasporto

The present study aims at implementing a biomass transportation cost mapping, drawn thanks to the spatial analyses included in the Geographical Information System (GIS). The themes involved in the creation of the cost function can be identified in the use of soil, information concerning the punctual biomass availability, road system and morphology, and exact localisation of plants for processing wooden material, etc. The idea stands in the will to search for and afterwards apply a function able to match cost and distance by keeping in mind several parameters. Stepping back, the realisation of the transport cost function is useful in case we have not definitely placed the biomass processing plants in the whole area as it is in the region of Basilicata, the area analysed in the present proposal. The proposed analysis would be useful to identify the economically valid collection basins and the best positions where a new plant can be installed, and also the size itself of the biomass processing plant on the basis of the actual production conditions of the area.

Rheology of Heavy-Oil Emulsions

Summary Water is invariably produced with crude oil. If there is enough shear force when crude oil and produced water flow through the production path, stable emulsions may be formed. This scenario may particularly be present during the production of heavy oils, where steam is used to reduce the viscosity of heavy oil, or in cases in which submersible pumps are used to artificially lift the produced fluids. To efficiently design and operate heavy-oil production systems, knowledge of the realistic viscosities of the emulsified heavy oil, under the actual production conditions, is necessary. This study is an attempt to investigate the effect of water content, pressure, and temperature (i.e., operating conditions on the viscosity of live heavy-oil emulsions). Two heavy oil samples from South America were used for this study. The stock tank oil (STO) samples were recombined with the corresponding flash gases to reconstitute the original reservoir oil compositions. Live oil/water emulsions were prepared in a concentric cylinder shear cell using synthetic formation water, under predetermined pressure, temperature, and shear conditions. The stability of live emulsions was investigated using a fully visual pressure/volume/temperature (PVT) cell, while viscosities were measured using a precalibrated, high-pressure capillary viscometer. Viscosities were measured at least in three different flow rates at the testing conditions. In addition to live-oil emulsion studies, the stability and droplet size distribution of STO emulsions were also determined. Experimental results indicated that the inversion point for the STO emulsions was approximately 60% water cut (volume), and the average droplet size was increasing with water content. For all measured cases, viscosities varied with temperature according to an Arrhenius relation, while viscosities did not indicate any variation with flow rate (shear) within the range of tested flow rates. Measured viscosities also increased as pressure decreased below the bubblepoint of the sample as lighter hydrocarbon components evolved. The measured viscosities increased as much as 500% because of the presence of emulsions before a sharp drop in viscosity beyond the inversion point. The variation of viscosity with water content for live emulsion samples indicated that the inversion point for live emulsions is similar to that of STO samples. The experimental results are also used to analyze and evaluate the performance of an ESP system when water cut increases and causes emulsion in a well.

Reduced Well Spacing Combined With Polymer Flooding Improves Oil Recovery From Marginal Reservoirs

This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SPE 96946, "Combining Small Well Spacing With Polymer Flooding To Improve Oil Recovery of Marginal Reservoirs," by J. Cheng, D. Wang, X. Sui, SPE, H. Zeng, and W. Bai, SPE, Daqing Oilfield Co. Ltd., prepared for the 2006 SPE/DOE Symposium on Improved Oil Recovery, Tulsa, 22,–26 April. The full-length paper details laboratory studies of polymer-injection parameters and project-design optimization. On the basis of these studies, a pilot test combining close well spacing and polymer flooding was undertaken. Well spacing was 100 m, zone thickness was less than 1 m, and permeability was 5 to 10 md. Both laboratory studies and pilot results show increased volumetric sweep efficiency. The pilot test indicates that combining infill wells with polymer flooding is economically feasible with 10% original-oil-in-place incremental recovery at a production cost of U.S., $10/bbl. Introduction In continental, multilayer, heterogeneous sandstone oil fields, some reservoirs with poor connectivity and low permeability have low recovery factors. The low degree of layer connection and inner-layer interferences lead to poor waterflooding efficiency. To improve oil recovery and increase recoverable reserves, infill wells were drilled to improve reservoir connectivity and a polymer solution was injected. Average incremental oil per day for a single well was 1.83 times original production. Water cut decreased 10.2%, and oil recovery increased more than 10%. Pilot Area The pilot-test area was an inverted-five-spot well pattern with 25 wells—nine injectors and 16 producers (Fig. 1). Distance between injectors and producers was 100 m. Target zones comprise the marginal Sa and Pu II reservoirs. Polymer flooding focused on layers with permeability of 100 md or less that account for 84% of the total layers. Layers with an effective thickness of less than 1 m account for 90% of the total. Laboratory Core studies show that the lower the permeability, the lower the molecular weight (MW) of polymer required. Because the target reservoirs have low permeabilities and small pore radius, appropriate polymer MW must be chosen on the basis of reservoir properties. Laboratory studies determined the upper limit of polymer MW on the basis of reservoir permeability. Polymers with a 2.4×106 MW satisfy the needs of reservoirs with a 20×10−3-µm2 permeability, while 5.5×106 MW is suit -able for reservoirs with a 50×10−3-µm2 permeability, and 10×106 MW is suitable for reservoirs with a 200×10−3-µm2 permeability. Polymer-Injection Trial Before the pilot test, one well was selected for a trial to determine the injection parameters for the entire test area. Polymer with a 7×106 MW was injected at a concentration of 600 mg/L in the first injection well. The injection process worked very well at an 8.0-MPa injection pressure. No injection-pressure buildup was observed for any of the layers, indicating that all had some injectivity. Gradual adjustments were made as a result of the actual injection conditions. Injection viscosity at the wellhead reached 12 to 17 mPa.s, and the injection rate was 0.25 to 0.33 pore volumes (PVs)/a. Polymer-injection volume was determined by the actual production conditions.

Greenhouse-gas emissions from solar electric- and nuclear power: A life-cycle study

Solar- and nuclear-electricity-generation technologies often are deemed “carbon-free” because their operation does not generate any carbon dioxide. However, this is not so when considering their entire lifecycle of energy production; carbon dioxide and other gases are emitted during the extraction, processing, and disposal of associated materials. We determined the greenhouse gas (GHG) emissions, namely, CO 2, CH 4, N 2O, and chlorofluorocarbons due to materials and energy flows throughout all stages of the life of commercial technologies for solar-electric- and nuclear-power generation, based on data from 12 photovoltaic (PV) companies, and reviews of nuclear-fuel life cycles in the United States, Europe, and Japan. Previous GHG estimates vary widely, from 40 to 180 CO 2-eq./kWh for PV, and 3.5–100 CO 2-eq./kWh for nuclear power. Country-specific parameters account for many of these differences, which are exacerbated by outdated information. We conclude, instead, that lifetime GHG emissions from solar- and nuclear-fuel cycles in the United States are comparable under actual production conditions and average solar irradiation, viz., 22–49 g CO 2-eq./kWh (average US), 17–39 g CO 2-eq./kWh (south west) for solar electric, and 16–55 g CO 2-eq./kWh for nuclear energy. However, several factors may significantly change this picture within the next 5 years, and there are unanswered questions about the nuclear fuel cycle that warrant further analyses.

Economics of alternative simulated manual asparagus harvesting strategies

Asparagus is harvested daily during the production season. The adoption of harvesting strategies less or more frequent than the traditional 24-h strategy has not occurred because of problems in hiring manual labor. A model that predicts daily harvest and the impact of different harvesting strategies was developed. This paper presents a bioeconomic model, capable of predicting daily asparagus harvests, composed by different mathematical functions: emergence, density dynamics, spear growth, diameter, weight, carbohydrates reserve dynamics, and profit. The bioeconomic model was used to simulate yield, number of harvests, profit, and the total cost of harvest for every year in the period 1989–2004. A simulation with the minimum wage harvesting constraint was developed and is labeled as the constrained model. The model was evaluated using data from different locations for four consecutive years in Washington State (USA) asparagus fields. The impact of the minimum wage requirements was estimated in terms of yield and profit for both processed and fresh asparagus. The traditional harvest interval of 24 h was compared to a more frequent (12 h) and a less frequent (48 h) interval. Manual harvest with the interval of 12 h showed the best results in terms of yields and profits for both processed and fresh asparagus. Gains in profits with the actual production conditions in Washington State were US$183.88/ha and US$210.60/ha for processed and fresh product, respectively. The 48-h strategy resulted in decreased yields and profits.

Importance of practical measures and agroecological conditions for formation of yield and quality of sugar beet in Vojvodina

Yields of cultivated plants are the result of congruence between cultivated plant demands and agro ecological conditions of the region. Fertilization is a practical measure associated with the highest losses. In actual production conditions, deficiency in NPK nutrition results in losses up to 2.1-14.9 t ha?1, excess amounts of these nutrients in losses of 5.8-18.9 t ha?1. Quality losses are important, too. Decreases in sugar content fluctuate between 0,2% and 0,9%, sugar utilization from 0,3-7,6% and total sugar losses from 380 to 1060 kgha?1.

Normal‐flow virus filtration: detection and assessment of the endpoint in bioprocessing

The breakthrough of a model virus, bacteriophage PhiX-174, through normal-flow virus filters was studied using both commercial process fluids and model feed streams. The results indicate that (i) PhiX-174 is a reasonable model for a mammalian parvovirus [MMV (murine minute virus)] in virus filtration studies; (ii) PhiX-174 LRV [log(reduction value)] shows a better correlation with percentage flow decline compared with volume processed under a variety of conditions; (iii) although the extent of decline in virus LRV is dependent on the mechanism of filter fouling, the fouling mechanisms operative in a viral validation study are representative of those likely to be found under actual production conditions. The mechanism of LRV decline by many process streams was proposed to be due to selective plugging of small pores. A theoretical model as well as a predictive equation for LRV decline versus flow decay was derived; experimental results from filtration studies using pore-plugging feed stocks were consistent with the equation. As protein solutions may vary in their adsorptive versus plugging behaviour during filtration, an evaluation of the LRV-versus-flow-decay relationship on a biopharmaceutical-product-specific basis may be warranted.

Survival, growth and persistence under farm conditions of a Lactobacillus plantarum strain inoculated into liquid pig feed

To investigate the survival and persistence of Lactobacillus plantarum REB1 in the fermentation process of liquid pig feed on a working farm in standard production conditions. Two feed types, a control diet [nonfermented liquid feed (NFLF)] and a fermented diet [fermented liquid feed (FLF)], were compared. A rifampicin-resistant mutant L. plantarum REB1-Rif was used to initiate the fermentation of the feed. Inoculation with the experimental strain was repeated one or two times per week throughout the three month growing period. Four microbial groups were followed using standard microbiological techniques, as well as pH. Lactic acid bacteria (LAB) counts were high already at the beginning in FLF, while it took nine days to reach the corresponding LAB levels in NFLF. Yeasts were stable in FLF, whereas in NFLF there were occasional high counts during the first week. The numbers of Enterobacteriaceae were low, although in NFLF they were variable. The average pH in NFLF was 4.5 and 4 in FLF. The inoculation of L. plantarum REB1-Rif provided a LAB population of log 9 colony forming units (CFU) ml(-1) from the first feeding day, stable numbers of yeast and pH, and a drastic reduction of Enterobacteriaceae. The inoculation by L. plantarum REB1-Rif offered a FLF microbiologically stable from the first week in actual production conditions.

Endogenous technological change and emissions: the case of the German steel industry

The paper starts from the observation that innovation and technical progress are only portrayed superficially in the predominant environmental economic top-down models, and that the assumption of perfect factor substitution does not correctly mirror actual production conditions in many energy-intensive production sectors. Bottom-up models, on the other hand, neglect macroeconomic interdependencies between the modelled sector and the general economy. This paper presents a new modelling approach: in an integrated bottom-up/top-down approach based on the example of crude steel production in Germany, it is demonstrated how technological progress can be portrayed as process-related and policy-induced and how the technology choice between limitational processes can be explicitly modelled and implemented in the econometric input–output model PANTA RHEI. The new modelling approach presented permits a process-specific analysis of the impacts of changed frame conditions, the effects of which on the choice of technology, on the one hand, and the technological progress on the other, can be described endogenous to the model. These features are demonstrated in a CO 2 tax simulation. Results show that policy-induced technological change is—besides a switch in production processes—the major source of CO 2 reduction for the steel sector.

Estimating Metabolism of Fish in Aquacultural Production Systems

Open-system respirometry offers a practical approach for measuring metabolic rates of fish cultured at high densities in uncovered raceways. Central to this methodology is analysis of a dynamic mass-balance on oxygen supply and demand. Here, we present a validated mass-balance equation, describe minimally disruptive procedures for estimating its parameters, and illustrate its use in estimating the oxygen-uptake rate of fish as a group, in real time and under actual production conditions.

A combined infrared/heat pump drying technology applied to a rotary dryer

The short drying time and low product temperature makes it suitable for drying such heat-sensitive materials as herbs and vegetables. The purpose of this work was to develop a small-scale dryer for herbs and vegetables. A prototype rotary dryer combining infrared radiation with a so-called heat pump drying method was applied in drying experiments for several herbs and vegetables. The drying experiments were performed under actual crop production conditions. The drying curves for leaves of birch (Betula spp.), rosebay willowherb (Epilobium angustifolium) and dandelion (Taraxacum spp.) as well as slices of red beet (Beta vulgaris) and carrot (Daucus carota) are presented. During the drying operation, temperature and humidity of the drying air were recorded, as well as the energy consumed in drying. The quality parameters measured were water content, colour and rehydration ratio. In the present rotary dryer design, intermittent irradiation and mixing of the product enable to avoid overheating, which is particularly important for maintaining product quality. In this dryer design the drying drum slowly rotates and simultaneously mixes the product. The infrared heaters are attached to a panel, allowing the product to receive infrared radiation periodically.

Effect of melt cleanliness on the formation of porosity defects in automotive aluminium high pressure die castings

The effect of melt cleanliness on the formation of porosity defects in automotive aluminium high pressure die castings (TA Transmission Case) was investigated experimentally. The experiments were conducted under actual industrial production conditions at Nissan Casting Australia Pty Ltd. (NCAP). It was found that the probability of rejection due to excessive porosity present at critical locations in the castings (determined using a real-time X-ray radiographic method) increased as the number of inclusions in the melt (measured with LiMCA II) increased. The types of inclusion in the melt were identified as mainly amorphous oxides, oxide films and sludge particles.

Epidemiologic Method to Determine Losses Associated with Subclinical Gastrointestinal Nematodes in Yearling Cattle

In many northern regions of the United States, gastrointestinal nematode infections are largely subclinical, with relatively few cases of clinical disease. At subclinical levels the effects of nematodes are less apparent but lead to decreased rates of production and decreased immunity to various infectious diseases. Subclinical burdens may make it difficult for producers to recognize the loss, and the need to control these parasites. A convenient method to measure subclinical losses under actual herd production conditions is needed to enhance producers' ability to evaluate the cost-benefit of nematode control programs. The objective of this project was to evaluate an epidemiologic-based methodology, which measures losses due to subclinical gastrointestinal nematode infections in yearling cattle on a single pasture.

An evaluation of metallic coatings for erosive wear resistance in die casting applications

An accelerated testing procedure with a multi-pin die has been established for the study of the erosive wear of die materials and surface treatments in die casting applications, under production conditions. This test procedure utilizes the wear of core pins as a surrogate measure of die erosive wear, and is used to evaluate the efficacy of coatings and die surface treatments in reducing erosive wear in dies under actual production conditions. Metallic coatings of W, Mo, and Pt deposited on the test pins using the plasma source ion implantation technique (PSII) technology in the ion assisted deposition mode, were then evaluated for erosion resistance using this developed test procedure. The results of this evaluation on the effectiveness of these metallic coatings are presented here along with possible reasons for such coating behavior.

Air Pollution and Farm-Level Crop Yields: An Empirical Analysis of Corn and Soybeans

While many studies have estimated the impacts of air pollution on crop yields on experimental plots, few have estimated these impacts under actual farm production conditions. This study econometrically estimates the impact of air pollution on corn and soybean yields, controlling for weather, soil quality and management practices, using farm-level data for the eastern United States. Ozone pollution was found to reduce yields for both crops. The mean elasticity of yield with respect to ozone exposure was − 0.19 for corn and − 0.54 for soybeans. The benefits of ozone standards to protect crops, measured in terms of crop revenues, range from $17 to $82 million depending on the stringency of the standard. Over 85 percent of the revenue gains are captured by three states: Maryland, North Carolina, and Virginia.

Experimental and numerical investigation of the effect of process parameters on the erosive wear of die casting dies

This study investigates the causes and the mechanism of erosive wear in die casting dies, which are commonly made of H-13 die steel, by controlled experiments and computer simulations. Experiments were carried out under actual production conditions for a range of process and geometrical conditions with the accelerated erosive wear of core pins being used as a surrogate measure of die erosive wear. This paper reports the results of an investigation of the effect of metal velocity, inlet melt temperature, and the angle of metal impact on erosive wear in die casting dies. The study shows that in die casting, the erosive wear profile exhibits a strong correlation with the impact velocity profile, the erosive wear rate increases with a decrease in the inlet melt temperature, and the maximum erosive wear takes place at a metal impact angle of 72°. This indicates that the primary driver of erosion in die casting is the impact of partially solidified metal or solid particles at high velocities, with diffusion effects not being as critical.