Plant-scale System Research Articles

Valorization of chicken intestine: A process of protein hydrolysate for fish feed attractant using pilot plant scale system

Chicken intestine as a poultry industry byproduct is rich in protein, contains various endogenous enzymes and can be prepared as a hydrolysate via autolysis. This research examined the physicochemical properties of chicken hydrolysate as a feed attractant. Growth of fish fed on the chicken hydrolysate-coated diet was compared with fish fed on a commercial hydrolysate (C). Three chicken hydrolysates were prepared at 60 °C for 4 h on a pilot plant scale including autolysis at pH 3 (S1), supplemental enzyme addition at pH 6.11 (S2) and a combination of supplemental enzyme addition following autolysis at pH 3 (S3). Highest yield was found in S2 (76%) followed by S3 (74%) and S1 (72%). The chicken hydrolysate had lower protein content (13–16%), higher fat (21–23%) and lower viscosity at 7429–10607 cP compared with C. Degrees of hydrolysis (DH) of S1, S2, S3 and C were 56%, 73%, 65% and 61%, respectively. Highest number of peptides less than 3 kDa associated with feed palatability was found in S2 (76%), followed by S3 (49%), C (29%) and S1 (28%). The three chicken hydrolysates were rich in essential amino acids similar to the C sample but with smaller amounts of amino acids in S1 and S3 due to the acidic pH preparation. An 8-week feeding trial of two selected fish species (hybrid catfish and Nile tilapia) was conducted in a water-recirculation system to investigate the effect of different hydrolysate-coated diets on fish growth performance. Highest body weight of hybrid catfish at 65.20 g gave weight gain of 150.15% and specific growth rate 1.73% d−1. Optimal feed conversion ratio (FCR) at 1.49 was observed in the S2 diet (p < 0.05). Improved growth performance was observed in Nile tilapia for diets coated with all chicken hydrolysates but no significant difference was found (p ≥ 0.05). Highest values of the hematological parameters, including hemoglobin, hematocrit and mean corpuscular hemoglobin concentration, were found in the two fish groups fed with S1, S2 and S3 diets (p < 0.05). At the end of the experiment, hybrid catfish and Nile tilapia fed with the S2 and S3 diets had the highest fish body protein content at 17% and 16%, respectively (p < 0.05). Our results showed that the three chicken hydrolysates, particularly S2, could potentially be used as feed attractants for freshwater fish.

Full Core Pin-Level VVER-440 Simulation of a Rod Drop Experiment with the GPU-Based Monte Carlo Code GUARDYAN

Targeting ultimate fidelity reactor physics calculations the Dynamic Monte Carlo (DMC) method simulates reactor transients without resorting to static or quasistatic approximations. Due to the capability to harness the computing power of Graphics Processing Units, the GUARDYAN (GpU Assisted Reactor DYnamic ANalysis) code has been recently upscaled to perform pin-by-pin simulations of power plant scale systems as demonstrated in this paper. A recent rod drop experiment at a VVER-440/213 (vodo-vodyanoi enyergeticheskiy reaktor) type power plant at Paks NPP, Hungary, was considered and signals of ex-core detectors placed at three different positions were simulated successfully by GUARDYAN taking realistic fuel loading, including burn-up data into account. Results were also compared to the time-dependent Paks NPP in-house nodal diffusion code VERETINA (VERONA: VVER Online Analysis and RETINA: Reactor Thermo-hydraulics Interactive). Analysis is given of the temporal and spatial variance distribution of GUARDYAN fuel pin node-wise power estimates. We can conclude that full core, pin-wise DMC power plant simulations using realistic isotope concentrations are feasible in reasonable computing times down to 1–2% error of ex-core detector signals using current GPU (Graphics Processing Unit) High Performance Computing architectures, thereby demonstrating a technological breakthrough.

Discrete and Continuum Approaches for Modeling Solids Motion Inside a Rotating Drum at Different Regimes

In this work, the performance of discrete and continuum computational models for addressing granular flow dynamics in a rotating drum at different regimes is studied. The results are compared to the experimental observations obtained by image processing of a high-speed camera on a pilot plant rotating drum. For the discrete modeling, Discrete Elements Method (DEM) through the open-source software LIGGGHTS(R) is used, while for the continuum model, the μ(I)-rheology is implemented in the general structure of a Volume-Of-Fluid (VOF) solver of the OpenFOAM(R) platform. Four test cases consisting of different sets of particles filling and rotational speed are considered and the results are analyzed in terms of solids distribution, the velocity of the particles, and mixing patterns. The solids distribution and velocities for each one of the tests considered are fairly similar between both computational techniques and the experimental observations. In general, DEM results show a higher level of agreement with the experiments, with minor differences that might be irrelevant in some cases (e.g., more splashing of particles for the fastest regimes). Among the drawbacks of the continuum model, it was unable to predict the slumping regime observed experimentally which can be attributed to the lack of a yield criterion and a slower dragging of the granular material when the drum is being accelerated, which can be attributed to the need of adding non-local effects to the rheology. On the other hand, the dynamic of the bed in the rolling and cascading regimes are accurately predicted by the continuum model in less time than DEM, even in a pilot plant scale system. These results suggest that the use of a continuum model with granular fluid rheology is more suited for simulating industrial-scale rotating drums at different regimes than DEM, but only if all the phenomenological features (i.e., yield criteria and non-local effects) are taken into account in the model.

Treatment of centrifugal mother liquid of polyvinyl chloride by internal circulation aerobic biofilm reactor: Lab to plant scale system

Centrifugal mother liquid (CML) is a typical poorly biodegradable organic wastewater generated during the production of polyvinyl chloride (PVC). A method of treating PVC centrifugal mother liquid by a high efficiency internal circulation aerobic biofilm reactor (four reactors lined up together) is presented in this study. The optimized technique was tested and evaluated in a lab and in a plant scale system. The effect of chemical oxygen demand (COD) removal efficiency was studied under different hydraulic retention time (HRT): 40, 20, 17, 14 and 12 h, respectively. Considering the efficiency and removal rate, the best HRT was 14 h. At HRT of 14 h, the average volume loading was 0.326 kg COD/(m3∙d). During the product shift from TL-1000 to TL-800 (two kinds of PVC products with different polymerization degree), the treatment efficiency of the system was not affected. Compared with the plant scale system, the results showed that in the lab setup the removal rates of centrifugal mother liquid of TL-1000 (total organic carbon (TOC) = 70–75 mg/L) and TL-800 (TOC = 20 mg/L) were 90%–95% and 80%–90%, respectively. While in the plant scale system, the removal rates of centrifugal mother liquid of TL-1000 and TL-800 were 80%–90% and 65%–80% (effluent TOC 7.5–12 mg/L), respectively. Biofilm formation by the microbial reproduction as well as intensive filamentous bacteria settlements were observed.

Conductive ZSM-5-Based Adsorbent for CO2 Capture: Active Phase vs Monolith

Among microporous adsorbents, zeolites constitute the reference materials in CO2-capture technologies, because of their high CO2 affinity, high chemical and thermal stability, and low cost. Being synthesized in powder form, they need to be shaped in pellets or monolith to be suitable for real applications. The process has a direct effect on CO2-capture properties of the material creating, in this sense, substantial differences between lab-scale (adsorbents) and plant-scale systems (adsorbers). The ability of the honeycomb monolith to efficiently separate gases of interest arises from the properties of its single components such as an active phase and a phase resulting from the decomposition of a binder. Moreover, the textural (i.e., pore distribution and exposed surface) and structural properties (e.g., amorphization) of the active phase can be modified in the conditions adopted during the process that leads to the final artifact. These modifications can affect the CO2-capture performances of the active p...

Enzymatic Hydrolysis of Anchovy Using Medium-High Pressure Pilot Plant Scale Systems

Enzymatic Hydrolysis of Anchovy Using Medium-High Pressure Pilot Plant Scale Systems

Thermal inactivation of Alicyclobacillus acidoterrestris spores under conditions simulating industrial heating processes of tangerine vesicles and its use in time temperature integrators

The aim of the present study was to characterize the thermal inactivation of Alicyclobacillus acidoterrestris spores under isothermal and non-isothermal conditions simulating industrial heating processes applied to tangerine vesicles. A microbiological time temperature integrator (TTI) suitable for estimating the severity of thermal processes applied to acid foods was also developed. The heat resistance of A. acidoterrestris was characterized by D105 °C = 0.63 min and z = 10.8 °C in tangerine juice, showing linear survival curves, without shoulders and tails. Under non-isothermal conditions, the use of isothermal data allowed for an accurate prediction of the inactivation. The spores were included in alginate TTIs and they were used to estimate the severity of thermal treatments applied both in a thermoresistometer Mastia and in a food pilot plant scale system, which allows fast heating of the product to 93 °C and then a short holding time (2 min). In the thermoresistometer, tangerine juice was used as heating medium. In the food pilot plant scale system, thermal treatments were applied in batch to unpackaged tangerine vesicles. In both equipments, the TTIs accurately predicted the lethality of the thermal treatments applied. The percent coefficients of variation for survivor counting in TTIs showed that distribution of heat is homogeneous both in the thermoresistometer and in the reactor, being lower than 10% in all cases. The logistic and normal distributions were found to be the best for fitting the different survivor datasets.

Enzymatic Hydrolysis of Fish Frames Using Pilot Plant Scale Systems

Papain was used to hydrolyse fish frames under controlled conditions at a batch-pilot plant scale- process, for the production of fish protein hydrolysates (FPH). Mass balance calculations were carried out so that the rate of hydrolysis, rate of protein solubilisation and yields could be estimated. Almost complete hydrolysis could be achieved in 1 hour, at 40oC, with no pH adjustment, at 0.5% (5 g.kg-1) enzyme to substrate ratio (E/S, were S is Kjeldahl protein) using whole fish frames (including heads and flaps). This was achieved both with the addition of water (1/1 to 2/1 frames/water) but more importantly from commercial considerations without the initial addition of water (after mincing of the fish material). The degree of protein solubilisation ranged between 71% - 86% w/w. Four different processes are described, namely: 1) a soluble spray-dried FPH powder 2) a liquid FPH 3) a partly soluble, spray dried FPH powder and 4) a crude, drum-dried protein for animal consumption. The amino acid profile of the FPH was identical to that of the parent substrate (fish frames).

Fixed bed reactor modelling and experimental data for catalytic dehydrogenation in seasonal energy storage applications

Dehydrogenation of methylcyclohexane to toluene is studied by modelling and experimentally in two fixed bed reactor systems in the laboratory and pilot plant scale. Kinetic and transport parameters are estimated and measured. Interstage membranes for hydrogen separation are used to improve efficiency and exceed equilibrium conversion by 1–12%. The complexity of modelling the laboratory scale necessitates a pseudo-homogeneous two-dimensional model to compensate for radial gradients giving satisfactory agreement between simulated and measured data. The pilot plant scale system is simpler to model, a pseudo-homogeneous one-dimensional model describes the system with good accuracy. The highest yield achieved in the pilot plant scale system is 98%.

Rheocasting

This paper reviews what we know, and what we do not know, about the rheology of semi-solid metals, and about practical, metal-forming processes (Rheocasting Processes) which utilize semi-solid metals. The unique innovation which makes the semi-solid forming process possible is vigorous agitation of metals during the first fifty percent. or so of solidification. This produces a highly fluid slurry of solid spheroids dispersed in liquid. Our fundamental understanding of the mechanisms of formation and deformation of these slurries is as yet limited. However, it is known that the size of the solid spheroids and the viscosity of a slurry are functions of the process variables ( e.g., shear and cooling rates) employed. Furthermore, it is known that such slurries are thixotropic, with a viscosity that decreases sharply with increasing shear rate. Rheocast slurries have been produced of a variety of alloys including aluminum alloys, bronzes, cast iron, stainless steel and super-alloys. Extensive research has been carried out to develop an economic machine (die) casting process which will utilize the semi-solid slurries as charge material. Potential practical advantages of such a system include (a) long die- and shot-chamber life, (b) sound, reliable casting, (c) ability to achieve precise, automated metal metering to the die-casting machine. A die-casting system has been developed which utilizes the thixotropic nature of the slurries and so is called “Thixocasting”. The system combines a continuous slurry producer to provide Rheocast ingots, a reheating furnace, a “Softness Indicator” to determine when individual reheated charges are suitable for casting, and a commercial, cold chamber die-casting machine. A pilot plant scale system is currently operating, casting semi-solid stainless steel. At the present time, there is insufficient production experience to determine the extent to which the practical advantages of the process can be translated into economic and technical gains in the marketplace. Other potential applications of the Rheocast process are discussed. For example, non-metallic materials can be added to Rheocast slurries to produce composite material (Compocasting) and, we believe, continuous castings can be produced by the process that are more homogeneous, sounder, and of finer grain size than conventional ingots. So far we may only speculate that the technical advantages of these other applications of Rheocasting will be sufficient to lead to commercial application in the near future.