Process Development Steps Research Articles

Understanding the mechanism of polyethyleneimine-mediated cell disintegration and protein extraction in E. coli: The role of floc network formation and PEI molecular weight

Cell disintegration and protein extraction are crucial steps in downstream process development for biopharmaceuticals produced in E. coli. In this study, we explored the extraction mechanism of polyethyleneimine (PEI) at the cellular level and characterized the floc network that is formed upon PEI addition by Focused Beam Reflectance Measurement and Dispersion Analyzer. PEI disintegrates the cells by detachment of the outer membrane allowing protein to diffuse into the interspace of the flocs. Protein release into the supernatant occurs by diffusion out of the floc network. We could show that the type and concentrations of PEIs with varying molecular weight determines the floc properties and thus the extraction efficiency. We could demonstrate why optimal conditions, using 70 kDa PEI at 0.25 g/g cell dry mass, lead to efficient extraction while at suboptimal conditions extraction is almost negligible. Our findings provide valuable insights into the relationship between floc properties and PEI-driven protein extraction, with potential applications in bioprocessing and biotechnology.

Screening Clones for Monoclonal Antibody Production Using Droplet Microfluidics Interfaced to Electrospray Ionization Mass Spectrometry.

As one of the most critical steps in process development for protein therapeutics, clone selection and cell culture optimization require a large number of samples to be screened for high titer and desirable molecular profiles. Typical analytical techniques, such as chromatographic approaches, often take minutes per sample which are inefficient for large-scale screenings. Droplet microfluidics coupled to mass spectrometry (MS) represents an attractive approach due to its low volume requirements, high-throughput capabilities, label-free nature, and ability to handle complex mixtures. In this work, we coupled a modified protein cleanup protocol with a droplet-MS workflow for mAb titer screening to guide clone selection. With this droplet approach we achieved a throughput of 0.04 samples/s with an LoD of 0.15 mg/mL and an LoQ of 0.45 mg/mL. To test its performance in a real-world setting, this workflow was applied to a 35-clone screen, where the top 20% producing clones were identified. In addition, we coupled our sample cleanup protocol to a high-resolution MS and compared the glycan profiles of the high titer clones. This work demonstrates that droplet-MS provides a rapid way of clone screening and cell culture optimization based on titer and molecular structure of the expressed proteins. Future work is aimed at increasing the throughput and automation of this droplet-MS technique.

From strain engineering to process development: monoclonal antibody production with an unnatural amino acid in Pichia pastoris

BackgroundExpansion of the genetic code is a frequently employed approach for the modification of recombinant protein properties. It involves reassignment of a codon to another, e.g., unnatural, amino acid and requires the action of a pair of orthogonal tRNA and aminoacyl tRNA synthetase modified to recognize only the desired amino acid. This approach was applied for the production of trastuzumab IgG carrying p-azido-l-phenylalanine (pAzF) in the industrial yeast Pichia pastoris. Combining the knowledge of protein folding and secretion with bioreactor cultivations, the aim of the work was to make the production of monoclonal antibodies with an expanded genetic code cost-effective on a laboratory scale.ResultsCo-translational transport of proteins into the endoplasmic reticulum through secretion signal prepeptide change and overexpression of lumenal chaperones Kar2p and Lhs1p improved the production of trastuzumab IgG and its Fab fragment with incorporated pAzF. In the case of Fab, a knockout of vacuolar targeting for protein degradation further increased protein yield. Fed-batch bioreactor cultivations of engineered P. pastoris strains increased IgG and IgGpAzF productivity by around 50- and 20-fold compared to screenings, yielding up to 238 mg L−1 and 15 mg L−1 of fully assembled tetrameric protein, respectively. Successful site-specific incorporation of pAzF was confirmed by mass spectrometry.ConclusionsPichia pastoris was successfully employed for cost-effective laboratory-scale production of a monoclonal antibody with an unnatural amino acid. Applying the results of this work in glycoengineered strains, and taking further steps in process development opens great possibilities for utilizing P. pastoris in the development of antibodies for subsequent conjugations with, e.g., bioactive payloads.

Implementation of Perforated Concentric Ring Walls Considerably Improves Gas-Liquid Mass Transfer of Shaken Bioreactors.

Since their first use in the 1930s, shake flasks have been a widely used bioreactor type for screening and process development due to a number of advantages. However, the limited gas-liquid mass transfer capacities—resulting from practical operation limits regarding shaking frequency and filling volumes—are a major drawback. The common way to increase the gas-liquid mass transfer in shake flasks with the implementation of baffles is generally not recommended as it comes along with several severe disadvantages. Thus, a new design principle for shaken bioreactors that aims for improving the gas-liquid mass transfer without losing the positive characteristics of unbaffled shake flasks is introduced. The flasks consist of cylindrical glass vessels with implemented perforated concentric ring walls. The ring walls improve the gas-liquid mass transfer via the formation of additional liquid films on both of its sides, whereas the perforations allow for mixing between the compartments. Sulfite oxidation experiments revealed over 200% higher maximum oxygen transfer capacities (OTRmax) compared to conventional shake flasks. In batch cultivations of Escherichia coli BL21 in mineral media, unlimited growth until glucose depletion and oxygen transfer rates (OTR) of up to 138 mmol/L/h instead of an oxygen limitation at 57 mmol/L/h as in normal shake flasks under comparable conditions could be achieved. Even overflow metabolism could be prevented due to sufficient oxygen supply without the use of unconventional shaking conditions or oxygen enrichment. Therefore, we believe that the new perforated ring flask principle has a high potential to considerably improve biotechnological screening and process development steps.

Development of a General PAT Strategy for Online Monitoring of Complex Mixtures—On the Example of Natural Product Extracts from Bearberry Leaf (Arctostaphylos uva-ursi)

For the first time, a universally applicable and methodical approach from characterization to a PAT concept for complex mixtures is conducted—exemplified on natural products extraction processes. Bearberry leaf (Arctostaphylos uva-ursi) extract is chosen as an example of a typical complex mixture of natural plant origin and generalizable in its composition. Within the quality by design (QbD) based process development the development and implementation of a concept for process analytical technology (PAT), a key enabling technology, is the next necessary step in risk and quality-based process development and operation. To obtain and provide an overview of the broad field of PAT, the development process is shown on the example of a complex multi-component plant extract. This study researches the potential of different process analytical technologies for online monitoring of different component groups and classifies their possible applications within the framework of a QbD-based process. Offline and online analytics are established on the basis of two extraction runs. Based on this data set, PLS models are created for the spectral data, and correlations are conducted for univariate data. In a third run, the prediction potential is researched. Conclusively, the results of this study are arranged in the concept of a holistic quality and risk-based process design and operation concept.

Intensified production of zeolite A: Life cycle assessment of a continuous flow pilot plant and comparison with a conventional batch plant

AbstractThis study investigates on the environmental impact of an intensified technology for the manufacturing of Zeolite A, one of the largest zeolites employed worldwide by volume and value. The technology under consideration is an oscillatory continuous‐flow synthesis, developed industrially by Arkema, and currently at pilot‐scale. Life cycle assessment (LCA) is used in this work to measure the sustainability of this emerging technology in an anticipatory fashion, before its full deployment, with the aim of driving the process development toward the minimization of the environmental footprint. The assessment explores the full life‐cycle of the production system and comprises comparative analysis, scenario analysis, and a hotspot analysis. Finally, the continuous‐flow technology is benchmarked against the environmental impact of a conventional batch production of zeolite A, based on a full‐scale commercial plant. The results evidence that significant benefits would stem from shifting from batch to continuous‐flow production. The comparative analysis reveals that the extent of the latter advantages depends on the impact category under consideration and directs the next steps of CF system's process development toward pivotal aspects such as the recirculation system to further reduce the system's environmental impacts. Regardless of the chosen production technology, a large share of the total environmental impact hinges on the production of NaOH, a building block of the synthesis, and hence is hardly mitigatable. On the whole, the findings of this work emphasize the need of prioritizing LCA during the development phase of emerging technologies and underline its efficacy to prevent waste of resources and capitals.

A rapid, simple and sensitive microfluidic chip electrophoresis mass spectrometry method for monitoring amino acids in cell culture media

The development and optimization of cell culture media for biotech applications is a fundamental step of process development. The composition of cell culture media requires an ideal blend of amino acids, vitamins, nucleosides, lipids, carbohydrates, trace elements and other components. The ability to monitor these constituents is required to ensure that cells receive sufficient nutrients to facilitate growth, viability and productivity. Analysis of cell culture media is challenging due to the range and diversity of compounds contained in this matrix and normally requires time consuming methods. A rapid, simple and sensitive microfluidic chip CE-MS method is described to monitor amino acids in chemically defined cell culture media from a Chinese hamster ovary cell line cultured over a period of 10 days. The described platform enabled the separation of 16 amino acids in less than 2 minutes and without the requirement for extensive sample preparation. The analytical parameters evaluated were precision, linearity, limit of detection and limit of quantification. The majority of essential amino acids were present in cell culture growth in high concentrations compared to non-essential amino acids. Over the course of the 10 days cell culture the concentration of certain amino acids declined by up to 100%. Microfluidic chip based CE-MS methods can be used effectively to obtain the consumption rates of amino acids in cell culture media during cell growth and to perform at-line monitoring and screening of cell culture status.

Automation and miniaturization: enabling tools for fast, high‐throughput process development in integrated continuous biomanufacturing

AbstractProcess development in the biotech industry leads to investments around hundred of millions of dollars. It is important to mitigate costs without neglecting the quality of process development. Biopharmaceutical process development is important for companies to develop new processes and be first to market, improve a pre‐established process, or start manufacturing a product available by patent expiry (biosimilars). Laboratory automation enables methodical and standardized process development. Miniaturization and parallelization empower laboratories to screen several experimental conditions and define operating windows for purification processes, improving process robustness. Together, they allow for fast and accurate process development in a fraction of the time and cost of nonminiaturized/nonparallel process development approaches. The most widely used High‐Throughput Screening technique is a liquid‐handling station and microfluidics is taking its first steps in process development. Both are attractive scale‐down tools for the characterization of bioprocesses and allow thousands of experiments to be performed per day. High‐Throughput Process Development (HTPD) has helped to achieve major breakthroughs in process optimization, both for upstream and downstream processing. Continuous processing is the next step in process development which leads to cost reduction, higher productivity and better quality control; the integration of upstream and downstream processes is seen as a major challenge. In this review, we will focus on the state‐of‐the‐art of miniaturized techniques for process development in the biotechnology industry, and how automation and miniaturization drive process development. A comparison between liquid‐handling stations and microfluidics is made and an indication is given of which tools are still lacking for HTPD in the context of Integrated Continuous Biomanufacturing. © 2021 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).

Multi-attribute method based characterization of antibody drug conjugates (ADC) at the intact and subunit levels

Antibody–drug conjugates (ADCs) represent an important class of new biopharmaceutical modalities. ADCs are highly complex and heterogeneous molecules, potentially containing numerous product-related structures, that can contribute to the quality, efficacy and safety of the product. To keep up with product life cycle related changes, wide-range and targeted characterization of product quality attributes (PQA) are of high demand. Multi-attribute methods (MAM) can screen numerous PQAs in a parallel fashion including product properties as well as product and process-related impurities. MAM is usually based on a bottom-up approach relying on the enzymatic digestion of the protein into peptides prior to mass spectrometry (MS). However, this processing workflow can result in considerable information loss, such as the drug distribution profile of an antibody-drug conjugate. Therefore, complementary MAM approaches, based on subunit and intact mass analyses, are necessary approaches offering the advantage of product identity confirmation, quantification of the different conjugated species and monitoring the drug-to-antibody ratio at the same time. In this work we introduce a high throughput MS based attribute tracking method for ADC characterization at the intact and subunit levels by simultaneously monitoring multiple PQAs. The workflow includes sample preparation and MS instrument suitability testing for heterogeneous lysine-linked ADCs, software solutions for routine PQAs tracking, method repeatability and an easy data review fitting perfectly into high throughput analyses. As methionine oxidation is one of the modifications that should be closely monitored at any step of process development, an important application to oxidative stress evaluation using forced degradation demonstrated the applicability of the workflow.

Batch Culture Formulation of Live Biotherapeutic Products.

Live biotherapeutic products (LBPs) are an emerging therapeutic modality that are clinically investigated for treating pathogenic infections and inflammatory diseases. A major class of LBPs are feces derived microbial consortiums which require numerous process development steps (e.g. separation, purification, blending) to facilitate LBP formulation into oral dosage forms. A subset of these LBPs circumvent the need for continuous fecal processing by batch culture for individual strains of microbes that are rationally defined and combined in the final LBP formulation. Separately, delivery formulations (e.g. polymer encapsulation) are being developed for LBPs to improve storage and intestinal engraftment; however, formulation requires additional manufacturing processes distinct from fecal processing or batch culture. Here, a streamlined approach termed batch culture formulation (BCF) is developed to combine the individual batch culture and formulation processes into a single-step process. Based on a previously described polymeric film formulation that encapsulates LBPs, BCF is shown to reduce the number of required processes to formulate LBP-films without altering LBP phenotype, function, or storage profiles compared to the standard LBP-film formulation approach. Additionally, it is demonstrated that BCF facilitates scaled-fabrication from the milligram to gram scale with predictable loading, highlighting the potential that BCF has for clinical translation.

Life cycle assessment and cost evaluation of emerging technologies at early stages: The case of continuous flow synthesis of Rufinamide

AbstractIn the pharma and fine chemical industries, the development of continuous flow technologies is a process intensification step of primary importance towards the manufacturing of high‐quality products, while reducing the environmental impact and cost of production. The sustainability and profitability of a process can be measured through life cycle Assessment and cost evaluation. However, when applied to emerging technologies, these need to be performed at different stages of the process development in order to limit the uncertainties arising from the scale‐up, and hence providing high‐fidelity projections of environmental impacts and costs at larger scales. The output of the assessment can in fact vary significantly depending on the maturity of the technology and this translates into having different results at commercial scale compared to early estimations. Therefore, in this article, we perform an assessment at two different scales of production, lab and mini‐pilot scale, with the aim of quantifying the uncertainties of the assessment related to the scale‐up, identifying the hotspots of the system, and hence providing guidelines for the further steps of process development. The subject of the assessment is the continuous flow synthesis of Rufinamide. It is the first time that this synthesis is evaluated at pilot‐scale. The results show that low yields in the cycloaddition drastically affect the waste management and the production of precursors, and hence increases environmental impacts and cost of production. This calls for the need of prioritizing the optimization of this synthesis step in order to deploy a green and economically competitive production technology.

On-line glucose monitoring by near infrared spectroscopy during the scale up steps of mammalian cell cultivation process development

NIR spectroscopy is a non-destructive tool for in-situ, on-line bioprocess monitoring. One of its most frequent applications is the determination of metabolites during cultivation, especially glucose. Previous studies have usually investigated the applicability of Near Infrared (NIR) spectroscopy at one bioreactor scale but the effect of scale up was not explored. In this study, the complete scale up from shake flask (1 L) through 20 L, 100 L and 1000 L up to 5000 L bioreactor volume level was monitored with on-line NIR spectroscopy. The differences between runs and scales were examined using principal component analysis. The bioreactor runs were relatively similar regardless of scales but the shake flasks differed strongly from bioreactor runs. The glucose concentration throughout five 5000 L scale bioreactor runs were predicted by partial least squares regression models that were based on pre-processed spectra of bioreactor runs and combinations of them. The model that produced the lowest error of prediction (4.18 mM on a 29 mM concentration range) for all five runs in the prediction set was based on the combination of 20 L and 100 L data. This result demonstrated the capabilities and the limitations of an NIR system for glucose monitoring in mammalian cell cultivations.

Combined Effects of Carbon and Nitrogen Source to Optimize Growth of Proteobacterial Methanotrophs

Methane, a potent greenhouse gas, and methanol, commonly called wood alcohol, are common by-products of modern industrial processes. They can, however, be consumed as a feedstock by bacteria known as methanotrophs, which can serve as useful vectors for biotransformation and bioproduction. Successful implementation in industrial settings relies upon efficient growth and bioconversion, and the optimization of culturing conditions for these bacteria remains an ongoing effort, complicated by the wide variety of characteristics present in the methanotroph culture collection. Here, we demonstrate the variable growth outcomes of five diverse methanotrophic strains – Methylocystis sp. Rockwell, Methylocystis sp. WRRC1, Methylosinus trichosporium OB3b, Methylomicrobium album BG8, and Methylomonas denitrificans FJG1 – grown on either methane or methanol, at three different concentrations, with either ammonium or nitrate provided as nitrogen source. Maximum optical density (OD), growth rate, and biomass yield were assessed for each condition. Further metabolite and fatty acid methyl ester (FAME) analyses were completed for Methylocystis sp. Rockwell and M. album BG8. The results indicate differential response to these growth conditions, with a general preference for ammonium-based growth over nitrate, except for M. denitrificans FJG1. Methane is also preferred by most strains, with methanol resulting in unreliable or inhibited growth in all but M. album BG8. Metabolite analysis points to monitoring of excreted formic acid as a potential indicator of adverse growth conditions, while the magnitude of FAME variation between conditions may point to strains with broader substrate tolerance. These findings suggest that methanotroph strains must be carefully evaluated before use in industry, both to identify optimal conditions and to ensure the strain selected is appropriate for the process of interest. Much work remains in addressing the optimization of growth strategies for these promising microorganisms since disregarding these important steps in process development could ultimately lead to inefficient or failed bioprocesses.

Application of a fed‐batch microtiter plate to overcome hurdles in the early steps of process development

Application of a fed‐batch microtiter plate to overcome hurdles in the early steps of process development

A sensitive and robust HPLC method to quantify recombinant antibody fragments in E. coli crude cell lysate

Antibody fragments (Fabs) represent a highly interesting class of biopharmaceuticals with a broad range of medical applications. They bind antigens comparable to full length monoclonal antibodies, but are smaller in size allowing increased tissue penetration, and lack the glycosylated Fc domain, which is why they can be produced in the prokaryotic expression host E. coli. Due to the presence of disulfide bonds Fabs are usually produced in the oxidative environment of the E. coli periplasm. Even though recombinant production in E. coli is cheaper and easier to realize than in mammalian cells, this intracellular production of the Fab in E. coli entails difficulties in subsequent product analytics. Whereas Fabs are produced extracellularly by mammalian cells and thus can be analyzed in the environment of a defined medium, recombinantly produced Fabs in E. coli have to be analyzed in crude cell lysate containing a lot of host cell proteins, host cell DNA and lipids. Thus, robust and sensitive HPLC analytics for Fab quantification is still scarce today and recombinant Fabs from E. coli are conventionally quantified by expensive and cumbersome immunoassays. In this study we developed a sensitive and robust affinity-based HPLC method for the quantification of recombinant Fabs in E. coli crude cell lysates with a limit of quantification down to 46 μg/mL and high reproducibility. This method will definitely be of key importance for strain generation as well as for early steps in upstream process development for recombinant E. coli producing Fabs.

Dry syngas purification process for coal gas produced in oxy-fuel type integrated gasification combined cycle power generation with carbon dioxide capturing feature

Electricity production from coal fuel with minimizing efficiency penalty for the carbon dioxide abatement will bring us sustainable and compatible energy utilization. One of the promising options is oxy-fuel type Integrated Gasification Combined Cycle (oxy-fuel IGCC) power generation that is estimated to achieve thermal efficiency of 44% at lower heating value (LHV) base and provide compressed carbon dioxide (CO2) with concentration of 93 vol%. The proper operation of the plant is established by introducing dry syngas cleaning processes to control halide and sulfur compounds satisfying tolerate contaminants level of gas turbine. To realize the dry process, the bench scale test facility was planned to demonstrate the first-ever halide and sulfur removal with fixed bed reactor using actual syngas from O2–CO2 blown gasifier for the oxy-fuel IGCC power generation. Design parameter for the test facility was required for the candidate sorbents for halide removal and sulfur removal. Breakthrough test was performed on two kinds of halide sorbents at accelerated condition and on honeycomb desulfurization sorbent at varied space velocity condition. The results for the both sorbents for halide and sulfur exhibited sufficient removal within the satisfactory short depth of sorbent bed, as well as superior bed conversion of the impurity removal reaction. These performance evaluation of the candidate sorbents of halide and sulfur removal provided rational and affordable design parameters for the bench scale test facility to demonstrate the dry syngas cleaning process for oxy-fuel IGCC system as the scaled up step of process development.

83 - Manufacturing solutions for autologous cell therapies

The long-term view of regenerative medicine therapies predicts an increased need for expansion solutions that are robust and are compatible with limited downstream processing steps. As more cell therapeutics progress through clinical testing, current in vitro culture methods lack efficiency and reproducibility. Moreover, single-use devices and high quality animal origin-free reagents support the future implementation of manufacturing solutions that will be required following clinical success. Here, we describe the implementation of single use bioreactors and high quality media for expansion of cell therapies. We focus on an example of autologous T cells. The presentation will review solutions addressing animal origin-free expansion of cells within the context of different upstream process development steps with good cell yield, high viability and maintenance of identity. Start to finish solutions for manufacturing, including high quality reagents, are key enabling technologies for success in commercializing cell therapies.

Cultivation-based strategies to find efficient marine biocatalysts.

Marine bacteria have evolved to survive in the marine environment by using unique physiological, biochemical and metabolic features and the ability to produce enzymes and compounds which may have commercial value. The Azores archipelago presents several ecosystems with strong volcanic activity where bacteria thrive under e.g. high temperatures. In this study, samples collected in the island of São Miguel were screened for biocatalysts possessing e.g. lipase, esterase, amylase, and inulinase activities. After isolation of several hundred bacterial strains, high throughput screening methods allowed the fast identification of biocatalysts. The first cultivation tests were performed on 24-wells microtiter plates with online oxygen monitoring and bacteria able to grow within 24 h were selected for further process development. Bacteria able to produce the desired enzymes were selected for the first round of tests. Four Bacillus strains presented high inulinase activity. The next step in process development was the determination of key parameters for enzyme activity such as temperature, pH, salinity and substrate concentration. The highest inulinase activity, 2.2 gsugars /gprotein h, was attained when the supernatant of a culture of a Bacillus subtilis strain was used in a magnetically stirred bioreactor. This study demonstrates how bacterial strains from marine environments may be used successfully in biotechnological processes.

Quasi-continuous parallel online scattered light, fluorescence and dissolved oxygen tension measurement combined with monitoring of the oxygen transfer rate in each well of a shaken microtiter plate.

BackgroundMicrotiter plates (MTP) are often applied as culture vessels in high-throughput screening programs. If online measuring techniques are available, MTPs can also be applied in the first steps of process development. For such small-scale bioreactors dipping probes are usually too large; therefore, optical measurements are often used. For example, the BioLector technology allows for the online monitoring of scattered light and fluorescence in each well of a continuously orbitally shaken MTP. Although this system provides valuable data, these measurements are mainly of a semi-quantitative nature. Therefore, signal calibration is required to obtain absolute values. With the µRAMOS technology it became possible for the first time to quantify the oxygen transfer rate (OTR) separately in each well of an MTP. In this work, a device is presented that combines both techniques, to provide a hitherto unparalleled high amount of information from each single well.ResultsBecause both systems (BioLector and µRAMOS) are based on optical measurements, the measurements need to be synchronized to avoid interferences with the optical signals. The new experimental setup was applied for online monitoring in cultures of Escherichia coli and Hansenula polymorpha. It has been demonstrated that the well-to-well reproducibility is very high, and that the monitored signals provide reliable and valuable information about the process. With varying filling volumes, different maximum oxygen transfer capacities (OTRmax) were adjusted in oxygen-limited cultures. The different degrees of stress during the culture due to oxygen limitation affected microbial growth and also impacted reproducibility from culture to culture. Furthermore, it was demonstrated that this new device significantly simplifies the experimental efforts: instead of parallel cultures in a shake flask and MTP, just one single experiment in MTP needs to be conducted to measure the OTR, dissolved oxygen tension (DOT), scattered light and fluorescence.ConclusionsThe new device is a very suitable system for the online monitoring of cultures in continuously orbitally shaken MTPs. Due to the high number of parameters that can simultaneously be measured with this small-scale device, deeper insight into the investigated microbial system can be achieved. Furthermore, the experimental efforts to obtain OTR, DOT, scattered light and fluorescence signals during a culture are decreased. Ultimately, this new technology and the resulting high amount of collected data will eliminate the currently existing separation between screening and process development.Graphical abstractPicture of the combined μRAMOS and BioLector setup which allows for measurements of the oxygen transfer rate (OTR), dissolved oxygen tension (DOT), scattered light and fluorescence in each single well of an orbitally shaken microtiter plate. Electronic supplementary materialThe online version of this article (doi:10.1186/s12934-016-0608-2) contains supplementary material, which is available to authorized users.

Simulation of closed nuclear fuel cycle processes as a tool for the development and optimization of radiochemical technologies

Computer models are being developed to determine the optimum conditions of nuclear fuel cycle processes. These models allow evaluating the flowsheets and making changes in them and in designing documents already in the step of process development as the results of experimental studies are being accumulated. The computational models being developed allow the designing and implementation of technologies to be considerably accelerated and the quality of their development and the operation efficiency and safety to be improved.