RESUMO
BACKGROUND: Although dendritic cell (DC)-based cancer vaccines represent a promising treatment strategy, its exploration in the clinic is hampered due to the need for Good Manufacturing Practice (GMP) facilities and associated trained staff for the generation of large numbers of DCs. The Quantum bioreactor system offered by Terumo BCT represents a hollow-fiber platform integrating GMP-compliant manufacturing steps in a closed system for automated cultivation of cellular products. In the respective established protocols, the hollow fibers are coated with fibronectin and trypsin is used to harvest the final cell product, which in the case of DCs allows processing of only one tenth of an apheresis product. MATERIALS AND RESULTS: We successfully developed a new protocol that circumvents the need for fibronectin coating and trypsin digestion, and makes the Quantum bioreactor system now suitable for generating large numbers of mature human monocyte-derived DCs (Mo-DCs) by processing a complete apheresis product at once. To achieve that, it needed a step-by-step optimization of DC-differentiation, e.g., the varying of media exchange rates and cytokine concentration until the total yield (% of input CD14+ monocytes), as well as the phenotype and functionality of mature Mo-DCs, became equivalent to those generated by our established standard production of Mo-DCs in cell culture bags. CONCLUSIONS: By using this new protocol for the Food and Drug Administration-approved Quantum system, it is now possible for the first time to process one complete apheresis to automatically generate large numbers of human Mo-DCs, making it much more feasible to exploit the potential of individualized DC-based immunotherapy.
Assuntos
Reatores Biológicos , Remoção de Componentes Sanguíneos , Vacinas Anticâncer , Técnicas de Cultura de Células , Células Dendríticas/citologia , Células Dendríticas/fisiologia , Monócitos/fisiologia , Automação Laboratorial/normas , Reatores Biológicos/normas , Remoção de Componentes Sanguíneos/instrumentação , Remoção de Componentes Sanguíneos/métodos , Remoção de Componentes Sanguíneos/normas , Vacinas Anticâncer/normas , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Indústria Farmacêutica/instrumentação , Indústria Farmacêutica/normas , Fidelidade a Diretrizes , Humanos , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/normas , Leucaférese/instrumentação , Leucaférese/métodos , Leucaférese/normas , Manufaturas/normas , Monócitos/citologiaRESUMO
Over the last several years, continuous manufacturing of pharmaceuticals has evolved from bulk APIs and solid oral dosages into the more complex realm of biologics. The development of continuous downstream processing techniques has allowed biologics manufacturing to realize the benefits (e.g., improved economics, more consistent quality) that come with continuous processing. If relevant processing techniques and principles are selected, the opportunity arises to develop continuous manufacturing designs for additional pharmaceutical products including liposomal drug formulations. Liposome manufacturing has some inherent aspects that make it favorable for a continuous process. Other aspects such as formulation refinement, materials of construction, and aseptic processing need development, but present an achievable challenge. This paper reviews the current state of continuous manufacturing technology applicable to liposomal drug product manufacturing and an assessment of the challenges and potential of this application.
Assuntos
Produtos Biológicos/isolamento & purificação , Reatores Biológicos , Indústria Farmacêutica/tendências , Lipossomos/isolamento & purificação , Tecnologia Farmacêutica/tendências , Produtos Biológicos/economia , Reatores Biológicos/economia , Reatores Biológicos/normas , Custos e Análise de Custo , Indústria Farmacêutica/economia , Indústria Farmacêutica/normas , Lipossomos/economia , Controle de Qualidade , Tecnologia Farmacêutica/economia , Tecnologia Farmacêutica/normas , Fluxo de TrabalhoRESUMO
Due to the growing interest in integrated continuous processing in the biopharmaceutical industry, productivity comparison of batch-based and continuous processes is considered a challenge. Integrated continuous manufacturing of biopharmaceuticals requires scientists and engineers to collaborate effectively. Differing definitions, for example, of volumetric productivity, may cause confusion in this interdisciplinary field. Therefore, the aim of this communication is to reiterate the standard definitions and their underlying assumptions. Applying them to an exemplary model scenario allows to demonstrate the differences and to develop recommendations for the comparison of productivity of different upstream processes.
Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Técnicas de Cultura Celular por Lotes/normas , Biofarmácia/normas , Reatores Biológicos/normas , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Técnicas de Cultura Celular por Lotes/economia , Biofarmácia/economia , Reatores Biológicos/economia , Células CHO , Contagem de Células , Cricetulus , Meios de Cultura , Modelos TeóricosRESUMO
BACKGROUND: Expanding quantities of mesenchymal stem cells (MSCs) sufficient to treat large numbers of patients in cellular therapy and regenerative medicine clinical trials is an ongoing challenge for cell manufacturing facilities. STUDY DESIGN AND METHODS: We evaluated options for scaling up large quantities of bone marrow-derived MSCs (BM-MSCs) using methods that can be performed in compliance with Good Manufacturing Practices (GMP). We expanded BM-MSCs from fresh marrow aspirate in αMEM supplemented with 5% human platelet lysate using both an automated cell expansion system (Quantum, Terumo BCT) and a manual flask-based method using multilayer flasks. We compared MSCs expanded using both methods and assessed their differentiation to adipogenic and osteogenic tissue, capacity to suppress T-cell proliferation, cytokines, and growth factor secretion profile and cost-effectiveness of manufacturing enough BM-MSCs to administer a single dose of 100 × 106 cells per subject in a clinical trial of 100 subjects. RESULTS: We have established that large quantities of clinical-grade BM-MSCs manufactured with an automated hollow-fiber bioreactor were phenotypically (CD73, CD90, CD105) and functionally (adipogenic and osteogenic differentiation and cytokine and growth factor secretion) similar to manually expanded BM-MSCs. In addition, MSC manufacturing costs significantly less and required less time and effort when using the Quantum automated cell expansion system over the manual multilayer flasks method. CONCLUSION: MSCs manufactured by an automated bioreactor are physically and functionally equivalent to the MSCs manufactured by the manual flask method and have met the standards required for clinical application.
Assuntos
Reatores Biológicos/normas , Técnicas de Cultura de Células/métodos , Instalações Industriais e de Manufatura/normas , Células-Tronco Mesenquimais/citologia , Automação , Reatores Biológicos/economia , Células da Medula Óssea/citologia , Técnicas de Cultura de Células/normas , Proliferação de Células , Análise Custo-Benefício , HumanosRESUMO
This study developed an innovative A-B process for enhanced nutrients removal in municipal wastewater reclamation, in which a micro-aerated moving bed biofilm reactor served as A-stage and a step-feed sequencing batch reactor (SBR) as B-stage. In the A-stage, 55% of COD and 15% of ammonia nitrogen was removed, while more than 88% of the total nitrogen was removed via nitritation and denitritation, together with 93% of phosphorous removal at the B-stage where ammonia oxidizing bacteria activity was significantly higher than nitrite oxidizing bacteria activity. Meanwhile substantial phenotype of polyphosphate accumulating organisms (PAOs) was also observed in the B-stage SBR. Fluorescence in situ hybridization revealed that Accumulibacter was the dominant PAOs with undetectable Competibacter. Compared to the conventional activated sludge process, the proposed A-B process could offer a more cost-effective alternative for enhanced biological nutrients removal from municipal wastewater with less energy consumption.
Assuntos
Reatores Biológicos/normas , Águas Residuárias/microbiologia , Purificação da Água/métodos , Amônia/metabolismo , Betaproteobacteria/metabolismo , Reatores Biológicos/microbiologia , Desnitrificação , Nitrificação , Nitritos/metabolismo , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Polifosfatos/metabolismo , Purificação da Água/economiaRESUMO
Monoclonal antibodies currently dominate the biopharmaceutical market with growing sales having reached 80 billion USD in 2016. As most top-selling mAbs are approaching the end of their patent life, biopharmaceutical companies compete fiercely in the biosimilars market. These two factors present a strong motivation for alternative process strategies and process optimization. In this work a novel purification strategy for monoclonal antibodies comprising phenylboronic acid multimodal chromatography for capture followed by polishing by ion-exchange monolithic chromatography and packed bed hydrophobic interaction chromatography is presented and compared to the traditional protein-A-based process. Although the capital investment is similar for both processes, the operation cost is 20% lower for the novel strategy. This study shows that the new process is worthwhile investing in and could present a viable alternative to the platform process used by most industrial players.
Assuntos
Anticorpos Monoclonais , Reatores Biológicos , Cromatografia Líquida , Animais , Anticorpos Monoclonais/economia , Anticorpos Monoclonais/isolamento & purificação , Reatores Biológicos/economia , Reatores Biológicos/normas , Ácidos Borônicos/química , Células CHO , Cromatografia Líquida/economia , Cromatografia Líquida/normas , Cricetinae , Cricetulus , Interações Hidrofóbicas e HidrofílicasRESUMO
In order to operate profitably under different product demand scenarios, biopharmaceutical companies must design their facilities with mass output flexibility in mind. Traditional biologics manufacturing technologies pose operational challenges in this regard due to their high costs and slow equipment turnaround times, restricting the types of products and mass quantities that can be processed. Modern plant design, however, has facilitated the development of lean and efficient bioprocessing facilities through footprint reduction and adoption of disposable and continuous manufacturing technologies. These development efforts have proven to be crucial in seeking to drastically reduce the high costs typically associated with the manufacturing of recombinant proteins. In this work, mathematical modeling is used to optimize annual production schedules for a single-product commercial facility operating with a continuous upstream and discrete batch downstream platform. Utilizing cell culture duration and volumetric productivity as process variables in the model, and annual plant throughput as the optimization objective, 3-D surface plots are created to understand the effect of process and facility design on expected mass output. The model shows that once a plant has been fully debottlenecked it is capable of processing well over a metric ton of product per year. Moreover, the analysis helped to uncover a major limiting constraint on plant performance, the stability of the neutralized viral inactivated pool, which may indicate that this should be a focus of attention during future process development efforts.LAY ABSTRACT: Biopharmaceutical process modeling can be used to design and optimize manufacturing facilities and help companies achieve a predetermined set of goals. One way to perform optimization is by making the most efficient use of process equipment in order to minimize the expenditure of capital, labor and plant resources. To that end, this paper introduces a novel mathematical algorithm used to determine the most optimal equipment scheduling configuration that maximizes the mass output for a facility producing a single product. The paper also illustrates how different scheduling arrangements can have a profound impact on the availability of plant resources, and identifies limiting constraints on the plant design. In addition, simulation data is presented using visualization techniques that aid in the interpretation of the scientific concepts discussed.
Assuntos
Produtos Biológicos/química , Biofarmácia/normas , Indústria Farmacêutica/normas , Arquitetura de Instituições de Saúde , Preparações Farmacêuticas/química , Controle de Qualidade , Tecnologia Farmacêutica/normas , Fluxo de Trabalho , Técnicas de Cultura Celular por Lotes/normas , Biofarmácia/instrumentação , Biofarmácia/métodos , Reatores Biológicos/normas , Cromatografia/normas , Composição de Medicamentos , Indústria Farmacêutica/instrumentação , Indústria Farmacêutica/métodos , Filtração/normas , Modelos Teóricos , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/métodos , Fatores de TempoRESUMO
The performance of a submerged membrane bioreactor (MBR) with and without a novel microbial consortium (NMBR vs. CMBR) was compared to provide deeper insights into the effects of changes in water quality and dissolved organic matter (DOM) characteristics by a novel microbial consortium on the fouling characteristics of MBR processes. Despite similar operating conditions and identical DOM properties in the feed waters, NMBR exhibited a lower propensity to release polysaccharide-like compounds with low molecular weight by bacterial activities compared to CMBR. These compounds have a great fouling potential for MBR processes. Therefore, an increase in the transmembrane pressure (TMP) of NMBR (normalized TMP (TMP/TMP0): 1.14) was much slower and less significant than that observed in CMBR (TMP/TMP0: 2.61). These observations imply that the novel microbial consortium can efficiently mitigate membrane fouling by hydrophilic DOM in MBR processes.
Assuntos
Reatores Biológicos/microbiologia , Reatores Biológicos/normas , Membranas Artificiais , Consórcios Microbianos , Cromatografia em Gel , Interações Hidrofóbicas e Hidrofílicas , Peso Molecular , Compostos Orgânicos/análise , Polímeros , Poliestirenos , Polivinil , Pressão , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias/microbiologia , Qualidade da ÁguaRESUMO
A two-stage food waste digestion system involved a first stage hydrolysis reactor followed by a second stage methanogenic reactor. Organic loading rates (OLR) were increased from 6 to 15 g VS L(-1) d(-1) in the hydrolysis reactor and from 2 to 5 g VS L(-1) d(-1) in the methanogenic reactor. The retention time was fixed at 4 days (hydrolysis reactor) and 12 days (methane reactor). A single-stage digester was subjected to similar loading rates as the methanogenic reactor at 16 days retention. Increased OLR resulted in higher quantities of liquid fermentation products from the first stage hydrolysis reactor. Solubilisation of chemical oxygen demand peaked at 47% at the maximum loading. However, enhanced hydrolysis yields had no significant impact on the specific methane yields. The two-stage system increased methane yields up to 23% and enriched methane content by an average of 14% to levels of 71%.
Assuntos
Digestão , Alimentos , Resíduos , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/normas , Fermentação , Hidrólise , Metano/análise , Metano/metabolismoRESUMO
In the continued absence of an effective anti-HIV vaccine, approximately 2 million new HIV infections occur every year, with over 95% of these in developing countries. Calls have been made for the development of anti-HIV drugs that can be formulated for topical use to prevent HIV transmission during sexual intercourse. Because these drugs are principally destined for use in low-resource regions, achieving production costs that are as low as possible is an absolute requirement. 5P12-RANTES, an analog of the human chemokine protein RANTES/CCL5, is a highly potent HIV entry inhibitor which acts by achieving potent blockade of the principal HIV coreceptor, CCR5. Here we describe the development and optimization of a scalable low-cost production process for 5P12-RANTES based on expression in Pichia pastoris. At pilot (150 L) scale, this cGMP compliant process yielded 30 g of clinical grade 5P12-RANTES. As well as providing sufficient material for the first stage of clinical development, this process represents an important step towards achieving production of 5P12-RANTES at a cost and scale appropriate to meet needs for topical HIV prevention worldwide.
Assuntos
Fármacos Anti-HIV/metabolismo , Quimiocinas CC/biossíntese , Infecções por HIV/tratamento farmacológico , HIV/efeitos dos fármacos , Pichia , Fármacos Anti-HIV/isolamento & purificação , Fármacos Anti-HIV/farmacologia , Reatores Biológicos/economia , Reatores Biológicos/normas , Quimiocinas CC/isolamento & purificação , Quimiocinas CC/farmacologia , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Fermentação , Humanos , Concentração Inibidora 50 , Projetos Piloto , Internalização do Vírus/efeitos dos fármacosRESUMO
This study evaluated the performance of a full-scale upgrade of an existing wastewater treatment plant (WWTP) with the intermittent cyclic extended aeration system (ICEAS), located in Qingdao, China. The ICEAS system was not able to meet effluent standards; therefore, a series of modifications and control strategies were applied as follows: (1) floating plastic carriers were added to the tank to aid biofilm formation; (2) operation parameters such as mixing and aeration time, feeding rate, and settling time were adjusted and controlled with a real-time control system; (3) a sludge return system and submersible water impellers were added; (4) the aeration system was also improved to circulate carriers and prevent clogging. The modified ICEAS system exhibited efficient organic and nutrient removal, with high removal efficiencies of chemical oxygen demand (89.57 ± 4.10%), NH4(+)-N (95.46 ± 3.80%), and total phosphorus (91.90 ± 4.36%). Moreover, an annual power reduction of 1.04 × 10(7) kW·h was realized as a result of these modifications.
Assuntos
Biofilmes , Esgotos/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/normas , China , Fósforo/análise , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/instrumentaçãoRESUMO
New York City Environmental Protection in conjunction with City College of New York assessed the application of the anammox process in the reject water treatment using a moving bed biofilm reactor (MBBR) located at the 26th Ward wastewater treatment plant, in Brooklyn, NY. The single-stage nitritation/anammox MBBR was seeded with activated sludge and consequently was enriched with its own 'homegrown' anammox bacteria (AMX). Objectives of this study included collection of additional process kinetic and operating data and assessment of the effect of nitrogen loading rates on process performance. The initial target total inorganic nitrogen removal of 70% was limited by the low alkalinity concentration available in the influent reject water. Higher removals were achieved after supplementing the alkalinity by adding sodium hydroxide. Throughout startup and process optimization, quantitative real-time polymerase chain reaction (qPCR) analyses were used for monitoring the relevant species enriched in the biofilm and in the suspension. Maximum nitrogen removal rate was achieved by stimulating the growth of a thick biofilm on the carriers, and controlling the concentration of dissolved oxygen in the bulk flow and the nitrogen loading rates per surface area; all three appear to have contributed in suppressing nitrite-oxidizing bacteria activity while enriching AMX density within the biofilm.
Assuntos
Compostos de Amônio/metabolismo , Fenômenos Fisiológicos Bacterianos , Biofilmes , Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Poluentes Químicos da Água/metabolismo , Anaerobiose , Bactérias/genética , Proteínas de Bactérias/genética , Biodiversidade , Reatores Biológicos/microbiologia , Reatores Biológicos/normas , Cinética , Cidade de Nova Iorque , Nitrogênio/metabolismo , Oxirredução , Projetos Piloto , Reação em Cadeia da Polimerase em Tempo Real , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/economiaRESUMO
The preliminary design and economic assessment of small wastewater treatment plants (less than 2000 population equivalent) are issues of particular interest since wastewaters from most of these agglomerations are not covered yet. This work aims to assess nine different technologies set-up for the secondary treatment in such type of facilities embracing both economic and environmental parameters. The main novelty of this work is the combination of an innovative environmental decision support system (EDSS) with a pioneer approach based on the inclusion of the environmental benefits derived from wastewater treatment. The integration of methodologies based on cost-benefit analysis tools with the vast amount of knowledge from treatment technologies contained in the EDSS was applied in nine scenarios comprising different wastewater characteristics and reuse options. Hence, a useful economic feasibility indicator is obtained for each technology including internal and external costs and, for the first time, benefits associated with the environmental damage avoided. This new methodology proved to be crucial for supporting the decision process, contributing to improve the sustainability of new treatment facilities and allows the selection of the most feasible technologies of a wide set of possibilities.
Assuntos
Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Reatores Biológicos/normas , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Filtração/normas , Lagoas/química , Dióxido de Silício/química , Eliminação de Resíduos Líquidos/instrumentação , Purificação da Água/instrumentaçãoRESUMO
In the present study possibility of coupling stripper to remove ammonia to the UASB reactor treating poultry litter leachate was studied to enhance the overall performance of the reactor. UASB reactor with stripper as ammonia inhibition control mechanism exhibited better performance in terms of COD reduction (96%), methane yield (0.26m(3)CH(4)/kg COD reduced), organic loading rate (OLR) (18.5kg COD m(-3)day(-1)) and Hydraulic residence time (HRT) (12h) compared to the UASB reactor without stripper (COD reduction: 92%; methane yield: 0.21m(3)CH(4)/kg COD reduced; OLR: 13.6kg CODm(-3)day(-1); HRT: 16h). The improved performance was due to the reduction of total ammonia nitrogen (TAN) and free ammonia nitrogen (FAN) in the range of 75-95% and 80-95%, respectively by the use of stripper. G/L (air flow rate/poultry leachate flow rate) in the range of 60-70 and HRT in the range of 7-9min are found to be optimum parameters for the operation of the stripper.
Assuntos
Amônia/metabolismo , Reatores Biológicos/normas , Metano/metabolismo , Aves Domésticas/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biodegradação Ambiental , Reatores Biológicos/economia , Concentração de Íons de HidrogênioRESUMO
In engineered systems, biological nitrogen removal through partial nitrification to nitrite is of great interest. Accordingly, effect of operating parameters such as pH, DO and temperature on the accumulation of ammonia-oxidizers was investigated. pH of 8, DO of 0.3-0.5mg/l and temperature of 35 degrees C yielded a ratio of 0.9-1.5 of NO(2)N:NH(4)N in the effluent suitable as a feed for Anammox reactor. Microbial population shift during start-up was assessed using quinone profile, SEM and FISH. UQ-8 in the biomass, which is the predominant quinone in ammonia-oxidizers, increased from 24.8% on Day 1 to 61.2% on Day 136. Fluorescence in situ hybridization analysis in the reactor showed that ammonia-oxidizing bacteria gradually outcompeted other bacteria and was the dominant population. The morphology and inner structure of the granular sludge was observed using SEM and the photographs indicated that the aerobic granular sludge showed a shift towards spherical and small rod-shaped clusters.
Assuntos
Bactérias/metabolismo , Reatores Biológicos/normas , Nitrogênio/metabolismo , Quinonas/metabolismo , Esgotos/química , Amônia/metabolismo , Concentração de Íons de Hidrogênio , Hibridização in Situ Fluorescente , Microscopia Eletrônica de Varredura , Nitritos/metabolismo , Oxigênio/química , Esgotos/análise , Temperatura , Fatores de Tempo , Poluentes Químicos da ÁguaRESUMO
Several methods exist for increasing the scale of cell culture in the laboratory. While these methods provide significant increases in biomass, they are often prohibitively expensive for many laboratories. We have engineered a small-scale bioreactor with a novel means of introducing oxygen through the catalytic breakdown of hydrogen peroxide using a manganese oxide catalyst. We have also adapted and modified an existing assay for dissolved oxygen to be compatible with culture conditions. In this system we have been able to culture CHO cells at densities of up to 10(7) cells/mL without the use of automated feedback systems.
Assuntos
Reatores Biológicos/economia , Peróxido de Hidrogênio/química , Compostos de Manganês/química , Óxidos/química , Oxigênio/análise , Animais , Reatores Biológicos/normas , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Desenho de Equipamento/economia , Desenho de Equipamento/normas , Oxigênio/metabolismoRESUMO
It has been demonstrated that the combination of anaerobic-aerobic treatment is the best technological and economical solution for the treatment of high loaded wastewater. Where in the past aerobic treatment systems were still very acceptable due to the very good treatment efficiency, simplicity and robustness of the technology, this has, in most cases, been changed due to very stringent sludge disposal legislation. The anaerobic pretreatment takes care of approximately 80-90% of the overall treatment efficiency at high loading rates and low sludge production and low energy costs. The aerobic posttreatment takes care of the absolute high removal efficiency and nitrogen and phosphorus removal. Because of the low organic loading rate of the aerobic posttreatment also in this stage the sludge production is low. The combination of anaerobic-aerobic treatment results in a compact system capable of reaching high treatment efficiency at low sludge production and lower energy consumption. Waterleau Global Water Technology has developed LUCAS anaerobic-aerobic system that combines an Upflow Anaerobic Sludge Blanket (UASB) reactor with an aerobic, constant-level cyclic activated sludge system, which is very suitable for the treatment of high loaded wastewaters in general and brewery waste water in particular. It has been proven from several full scale upgrading projects that the UASB system is best suitable for implementation in the aerobic plants that have to be extended in capacity.
Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Bactérias Aeróbias/metabolismo , Bactérias Anaeróbias/metabolismo , Reatores Biológicos/normas , Eliminação de Resíduos Líquidos/economiaRESUMO
A very small-scale continuous flow reactor has been designed for use with enzymes in organic media, particularly for operational stability studies. It is constructed from fairly inexpensive components, and typically uses 5 mg of catalyst and flow rates of 1 to 5 mL/h, so only small quantities of feedstock need to be handled. The design allows control of the thermodynamic water activity of the feed, and works with temperatures up to at least 80 degrees C. The reactor has been operated with both nonpolar (octane) and polar (4-methyl-pentan-2-one) solvents, and with the more viscous solvent-free reactant mixture. It has been applied to studies of the operational stability of lipases from Chromobacterium viscosum (lyophilized powder or polypropylene-adsorbed) and Rhizomucor miehei (Lipozyme) in different experimental conditions. Transesterification of geraniol and ethylcaproate has been adopted as a model transformation.
Assuntos
Reatores Biológicos/normas , Enzimas Imobilizadas/química , Reologia/instrumentação , Água/química , Monoterpenos Acíclicos , Reatores Biológicos/economia , Chromobacterium , Estabilidade Enzimática , Desenho de Equipamento , Ésteres/síntese química , Lipase/química , Modelos Químicos , Rhizomucor , Solventes , Temperatura , Terpenos/química , TermodinâmicaRESUMO
Bioconversion of municipal solid waste-sludge blend by conventional high-rate and two-phase anaerobic digestion was studied. RDF (refused-derived fuel)-quality feed produced in a Madison, Wisconsin, USA, MRF (materials-recovery facility) was used. High-rate digestion experiments were conducted with bench-scale digesters under target operating conditions developed from an economic feasibility study. The effects of digestion temperature, RDF content of digester feed, HRT, loading rate, RDF particle size, and RDF pretreatment with cellulase or dilute solutions of NaOH or lime on digester performance were studied. A pilot-scale two-phase digestion plant was operated with 80:20 (weight ratio) RDF-sludge blends to show that this process exhibited a higher methane yield, and produced a higher methane-content digester gas than those obtained by single-stage, high-rate anaerobic digestion.
Assuntos
Bactérias Anaeróbias/metabolismo , Eliminação de Resíduos/métodos , Esgotos/microbiologia , Biodegradação Ambiental , Reatores Biológicos/economia , Reatores Biológicos/normas , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Metano/análise , Projetos Piloto , Eliminação de Resíduos/economia , Temperatura , WisconsinRESUMO
Different concepts of implementation of mechanical pretreatment for enhancing the biogas potential from fibers in manure feedstock were evaluated by sampling before and after macerators at different biogas plants and from a fiber separation unit. An increase of the biogas potential of up to 25% by pretreatment of the whole feed in the macerator before the reactor was observed. Implementation concepts with a treatment of the fibers alone after separation from the manure showed to be not efficient due to a low recovery of organic matter in the fibers by the separation unit. The low operational costs of a macerator make it attractive to use this pretreatment method for a more complete degradation of particulate organic matter. Investigation of the size distribution of the fibers showed that a change in biogas potential was not correlated to a smaller size of the fibers. Results from the macerators indicate that the biodegradability of the fibers is rather enhanced by shearing which is not necessarily reflected by a change in fiber size.