Uso do fosfogesso como fonte de sulfato para bactérias redutoras de sulfato em um reator contínuo de leito fluidizado / Phosphogypsum as sulfate source for sulphate-reducing bacteria in a continuous fluidized-bed reactor

RESUMO O fosfogesso (FG) é um dos principais subprodutos da produção de ácido fosfórico para fertilizantes. Esse sólido é constituído principalmente de sulfato de cálcio di-hidratado, podendo conter também metais tóxicos e acidez residual (pH 2-3). A disposição em pilhas próximas às usinas é o principal método de disposição, entretanto isso não soluciona os problemas ambientais, uma vez que pode haver lixiviação das pilhas de resíduo pela água da chuva, contaminando o solo e os corpos d'água. Portanto, a disposição do FG é um desafio para a indústria de fertilizantes. O FG pode ser utilizado como fonte de sulfato para a produção de sulfeto em reatores anaeróbios, utilizando bactérias redutoras de sulfato (BRS). O sulfeto gerado pode ser utilizado posteriormente para a produção de enxofre elementar ou usado na precipitação de metais de transição. No presente trabalho, avaliou-se a viabilidade do uso do FG como fonte de sulfato para as BRS em um reator contínuo de leito fluidizado alimentado com glicerol p.a. como substrato, e estudou-se a influência da variável tempo de detenção hidráulica (TDH) real no processo de biorredução do sulfato. Este último foi determinado em 15 ± 2,6 e 9,7 ± 1,2 h, respectivamente, para os valores teóricos de 10 e 8 horas, a partir do uso de cloreto de lítio como traçador. Para a razão DQO/SO4 2- igual a 1,9, obteve-se remoção de sulfato de 73 ± 11 e 75 ± 12%, respectivamente, para os TDHs 15 ± 2,6 e 9,7 ± 1,2 h. As taxas de remoção específicas de sulfato foram de 0,106 ± 0,04 e 0,179 ± 0,07 gSO4 2-/gSSV.d, respectivamente, para os TDHs 15 ± 2,6 e 9,7 ± 1,2 h.

ABSTRACT Phosphogypsum (PG) is one of the major byproducts of phosphoric acid production for fertilizers. It consists mainly of calcium sulfate dihydrate and may also contain toxic metals and residual acidity (pH 2-3). Generally, this waste is disposed in stacks near plants; however, this does not solve the environmental problems as there may be leaching of the waste piles by rainwater, contaminating the soil and water bodies. Therefore, PG disposal is a challenge for the fertilizer industry. This waste can be used as a sulfate source for sulfide production in anaerobic reactors using sulfate-reducing bacteria (SRB). The sulfide generated can be used later for the production of elemental sulfur or used in the precipitation of transition metals. This work evaluated the feasibility of using PG as a sulfate source for SRB in a continuous fluidized-bed reactor fed with glycerol p.a. as carbon source, and the hydraulic retention time (HRT) effect in the sulphate bioreduction process. The latter was determined at 15 ± 2.6 and 9.7 ± 1.2 h, respectively, for the theoretical values of 10 and 8 hours, from the use of lithium chloride as tracer. Sulfate removal at DQO/SO4 2- ratio of 1.9 was 73 ± 11 and 75 ± 12%, respectively, for HRT of 15 ± 2.6 and 9.7 ± 1.2 h. Specific sulfate removal rates were 0.106 ± 0.04 and 0.179 ± 0.07 gSO4 2-/gSSV.d, respectively, for HRT 15 ± 2.6 and 9.7 ± 1.2 h.

Research Progress of Granulation Technology for Taste Masking of Pharmaceutical Preparation / 中国实验方剂学杂志

In commonly used oral solid preparations, poor mouthfeel results in poor patient compliance with the drug, which in turn reduces the market competitiveness of the drug. The problem of taste masking of pharmaceutical preparations has always been one of the important problems faced by pharmaceutics. With the increasing demand for the taste of drugs, the methods of masking bad taste of drugs have gradually increased in recent years. By summarizing the relevant literature covering the bad taste of drugs, the commonly used taste masking techniques include the addition of taste masking agents, inclusion techniques, microsphere/microcapsule technology, solid dispersion technology, ion exchange technology and the like. However, in addition to the above taste masking techniques, in the manufacturing process of the solid preparation, the granulation technique also can achieve the shielding of the bad taste of the medicine, and the granulation technique is simple, and can well achieve the effect of masking the bad taste of the medicine. This paper systematically introduces the research progress of granulation technology in drug taste masking, in order to provide reference for the selection of drug taste masking technology. With the increasing demand for drug taste, drug masking technology has been paid more and more attention by the majority of preparation workers, however, there are still some problems, such as imperfect taste evaluation system and low specificity of methods. This series of problems need to be further studied and solved by relevant pharmaceutical researchers.

Application of FMEA and Bayesian Network in Risk Assessment of Fluidized Bed Granulation of Traditional Chinese Medicine / 中国实验方剂学杂志

Objective:To carry out the risk assessment on the factors in the process of granulation fluidized bed of traditional Chinese medicine(TCM) by using failure model and effect analysis(FMEA) and Bayesian network(BN), in order to effectively control risk factors and improve product quality. Method:The risk analysis of the fluidized bed granulation process was carried out by FMEA and the selected medium risk and high risk factors were taken as the main control points, the corresponding BN was established. The sensitivity analysis was used to screen out the main risk factors affecting particle fluidity, particle size uniformity, solubility and product cleanliness, the occurrence probability of each risk factor was determined by the evidence of unqualified particle quality, finally, taking fluidized bed granulation process of Sanye tablets as an example, the FMEA and BN were combined into the risk assessment process to verify the effectiveness and reliability of the method. Result:Based on the middle and high risk points of fluidized bed process, particle size of raw materials, moisture content and hygroscopicity of raw materials, dosage, concentration and addition amount of binder, cleaning degree and integrity of collection bag, and nozzle position, which were selected by FMEA, a fluidized bed granulation risk network with causality was constructed. Among them, hygroscopicity of raw materials, concentration and addition amount of binder, inlet temperature and atomization pressure were high probability risk factors, and the probability of occurrence were 55%, 63%, 59%and 58%, respectively. According to the Bayesian risk relationship network which controlled Sanye tablets fluidized bed granulation analysis results showed that the P values of inlet temperature, atomization pressure and concentration of binder were 0.003 4, 0.032 6 and 0.041 8, respectively in the regression model of influencing factors and particle size uniformity, indicating that there was a significant correlation between the three factors and the particle quality, which was basically consistent with the conclusion obtained by FMEA-BN method. Conclusion:The combination of FMEA and BN for visualized risk assessment of fluidized bed granulation helps to effectively control the risk factors in the granulation process, reduce product quality risks and provide strong support for the improvement of granulation process of TCM.

Study on on-line near-infrared spectroscopic for moisture monitoring in a fluidized bed drying process of Guzhi Fuling Capsules / 中草药

Objective: To establish a real-time moisture monitoring model for the fluidized bed drying process of Guizhi Fuling Capsules (GFC) by using online near-infrared spectroscopy (NIRS). Methods: A total of 176 samples from 16 production batches were collected by NIRS diffuse reflection probe for modeling. The moving window average smoothing method was used for spectral preprocessing. The characteristic variables were 4 759.45—5 338.00 cm−1, 5 503.84—6 101.67 cm−1, and 8 512.25—8 809.24 cm−1, which were screened by the interval partial least squares method (siPLS) combined with the moving window partial least squares (mwPLS). The partial variable least squares (PLS) method was used to build a multivariate correction model for moisture. Results: The root mean square error of cross-validation (RMSECV) of predicted moisture was 0.243%, the ratio of predicton to deviation (RPD) was 13.384, and the relative standard error of prediction (RSEP ) was 0.270%. The reliability of the online monitoring method was continuously verified by eight production batches. The relative error of 40 samples was less than 4.7%, indicating that the PLS quantitative model prediction performance was robust and accurate. The real-time monitoring trend chart of the moisture in the drying process can accurately determine the drying end point, and the moisture content of the end sample was within the control limit. Conclusion: The quantitative model established by online NIRS combined with PLS can be applied to the on-line monitoring of moisture content in the fluidized bed drying process of production scale GFC and the prediction performance was robust and accurate.

Moisture sorption and diffusion determination of Chinese herbal granules: Moisture-resistant effects of fluidized bed granulation with dextrin / 中草药·英文版

Objective: To investigate the effects of fluidized bed granulation with dextrin on moisture sorption and diffusion of Zexie Decoction granules. Methods: The particle characterization was studied by the particle size, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR). The moisture sorption isotherm, equilibrium moisture content (EMC), and moisture diffusion coefficients were determined by using the saturated salt solution method. Results: The particle size increased from 6.04 µm (powder) to 1201.47 µm (granule). The glass transition temperature of dextrin, Zexie Decoction powder, and granule was 107.13 °C, 94.82 °C, and 126.25 °C. As the increase of temperature, the initial rate of moisture sorption become higher. Furthermore, the initial rate of moisture sorption of Zexie Decoction granules was lower than those of powders and dextrin. The EMC and moisture diffusion coefficients were reduced significantly after granulation (P < 0.01). Critical relative humidity and diffusion activation energy of granules were higher than powders. Conclusion: Results suggested that fluidized bed granulation with dextrin could reduce the hygroscopicity of the Zexie Decoction extract powders and inhibited moisture diffusion, which is mainly related to the microstructure reorganization by fluidized bed granulation and anti-plasticizing effects of dextrin.

Two phases fermentative process for hydrogen and methane production from cassava wastewater / Processo fermentativo em duas fases para a produção de hidrogênio e metano a partir da manipueira

Introduction: Hydrogen and methane production was investigated in two phases of fermentative process. Objective: At the acidogenic phase, an anaerobic fluidized bed reactor was fed with cassava wastewater producing hydrogen. Methods: Expanded clay was used as a support material for biomass immobilization. The reactor was operated with HRT ranging from 8-1 h. Results: The best hydrogen yield production was 1.91 mol H2/mol glucose at HRT of 2 h. At the methanogenic phase, the acidogenic process effluent fed a fixed-bed reactor producing methane. Conclusion: Sururu (Mytella falcata) shells was used as support acted as pH neutralizer in the fixed-bed reactor, yielding best (0.430±0.150 Lmethane/gCOD) with 12h HRT phase. (AU)

Introdução: A produção de hidrogênio e metano foi avaliada em um processo fermentativo de duas fases. Objetivo: Na fase acidogênica, um reator anaeróbio de leito fluidificado foi alimentado com manipueira para a produção de hidrogênio. Métodos: Argila expandida foi utilizada com material suporte para a adesão microbiana. O reator foi operado com TDH, variando entre 8-1h. Resultados: O melhor rendimento de produção de hidrogênio foi 1.91 mol, H2/mol glicose em TDH de 2 h. Na fase metanogênica, o efluente do processo acidogênico alimentou um reator de leito fixo para a produção de metano. Conclusão: Conchas de Sururo (Mytella falcata) foram utilizadas como suporte, atuando como neutralizador do pH no reator de leito fixo, melhor rendimento (0.430±0.150 Lmethane/gDQO) na fase com TDH de 12h. (AU)

Preparation of colon-targeted pellets of Prunellae Spica effective components and the in vitro drug-release behaviors / 中成药

AIM To prepare colon-targeted pellets of Prunellae Spica effective components and to evaluate the in vitro drug-release behaviors.METHODS Fluidized bed coating method was adopted in the preparation of pellets.With in vitro accumulative release rate as an evaluation index,hydroxypropyl methyl cellulose (HMPC),polyacrylic resin (Eudragit S100) and triethyl citrate (TEC) amounts as influencing factors,orthogonal test was applied to optimizing the formulation.The in vitro drug-release behaviors were evaluated with rosmarinic acid content as an index.RESULTS The optimal formulation was determined to be 5％ for HPMC amount,70％ for Eudragit S100 amount,and 20％ for TEC amount.The obtained pellets attained an accumulative release rate of more than 90％ in pH 7.6 PBS (transportation for 2 h),while no drug dissolution was found in pH 1.0 HCl (transportation for 2 h) or pH 6.8 PBS (transportation for 3 h).CONCLUSION Colon-targeted pellets of Prunellae Spica effective components can achieve in vitro colon-targeted effect.

Influencing Factors in Fluidized Bed Granulation Process of Metformin Hydrochloride / 中国药师

Objective:To study the effects of process parameters of fluidized bed granulation on the physical properties of metform-in hydrochloride granule. Methods:The physical properties of metformin hydrochloride were used as the evaluation indices. Single fac-tor experiment was conducted to investigate the influences of equipment factors ( including the nozzle height and the nozzle orifice) and the process parameters ( including binder dosage, inlet air temperature, inlet air flow rate, spray rate and atomization pressure) on the physical prperties. Results: The influences of equipment factors on the physical properties of the granule were not significant. The binder dosage, inlet air temperature, inlet air flow rate, spray rate and atomization pressure showed significant influences on the physi-cal properties of metformin hydrochloride granule. Conclusion:The parameters of fluidized bed granulation process ( binder dosage, in-let air temperature, inlet air flow rate, spray rate and atomization pressure) have significant effects on the physical properties of met-formin hydrochloride granule, which should be controlled according to the requirements of granule properties.

Effect of fluidized bed technology on micromeritics properties of Leonurus Herba extract / 中国中药杂志

Based on different binders, the Leonurus Herba extract powders were fluidized and modified. The physical properties such as hygroscopicity, flowability, filling property and compression property were studied by various micromeritics methods before and after modification. The results showed that the physical properties of Leonurus Herba extract were close to those of microcrystalline cellulose, and its comprehensive flow index was between 61-75. Fluidization process can improve hygroscopicity, so the moisture absorption indexes of the samples were significantly lower than those of the original Leonurus Herba extract samples. With the plastic constant, compression ratio and yield stress, Heckel equation and Kawakita equation as the the investigation indicators, results showed that fluidization process based on binder water was superior to other methods in increasing the compressibility of the extracts. In low and medium pressure, the fluidized and modified extract can form the tablets with a certain strength. Fluidized transformation had a greater influence on the properties of original Leonurus Herba extracts, which was instructive to guide significance for the surface modification of pharmaceutical powders and provide the basis for the development of extract tablet.

Preparation of Mifepristone Gastric Retention Sustained-Release Pellet System Tablets and Their Release Characteristics in Vitro / 中国药学杂志

OBJECTIVE: To prepare mifepristone gastric retentive multi-unit pellet system (MUPs), and study its release behaviors in vitro. METHODS: A sustained release layer and mucous adhesive layer were coated onto extrusion spherized mifepristone pellets. The gastric retentive sustained release pellets were mixed with granules which were wet granulated from micronized mifepristone and compressed into MUPs tablets. Investigation and evaluation of the in vitro release of mifepristone MUPs tablets were carried out from different aspects. RESULTS: The turning point of pH value for the solubility of mifepristone was 3.0.Micronized mifepristone showed higher dissolving rate and apparent solubility. The gastric retentive mifepristone MUPs tablets had faster release than marketed mifepristone tablets. The in vitro adhesive experiment with pig stomach showed that mucous adhesive mifepristone pellets could be entrapped into the gastric mucous and retained for a long time. The accelerated stability study showed that mifepristone MUPs tablets were as stable as marketed mifepristone tablets. CONCLUSION: Novel mifepristone gastric retentive MUPs tablets are successfully prepared. The release characteristics in vitro indicate that the product may have higher bioavailability than marketed mifepristone tablets with significantly lower variability.

Eficiência na remoção de NAT, DBO e DQO utilizando reator aeróbio de leito fluidizado com circulação em tubos concêntricos associado ao decantador de coluna em uma produção intensiva de tilápia / Removal efficiency of TAN, BOD and COD by using aerobic fluidized bed reactor with circulation in concentric tubes associated to a column settler in intensive production of tilapia

RESUMO O desenvolvimento da aquicultura intensiva é acompanhado de um crescente impacto ambiental produzido pelos efluentes gerados. Os sistemas de recirculação para aquicultura (SRA) são uma alternativa compacta e trabalham com elevadas densidades de estocagem e menores volumes de água. Foi utilizado um decantador de coluna (DC) associado ao reator aeróbio de leito fluidizado com circulação em tubos concêntricos (BAS-CT) com tempo de retenção hidráulica (TRH) de 0,55 e 0,20 h respectivamente, num SRA com tilápias de 0,32 kg de peso médio e densidade de estocagem de 33,1 kg.m-3 em relação à remoção do nitrogênio amoniacal total (NAT), demanda bioquímica de oxigênio (DBO) e demanda química de oxigênio (DQO). As eficiências na remoção de NAT, DBO e DQO foram 35,2, 48,0 e 64,9%, respectivamente. No uso de DC com o BAS-CT, obteve-se bom desempenho, com baixos TRH no tratamento do efluente.

ABSTRACT The development of intensive aquaculture is accompanied by an increasing environmental impact produced by the wastewater generated. The recirculating aquaculture systems (RAS) are a compact alternative and manage high stocking densities and lower volumes of water. It was used a column settler (CS) associated with aerobic fluidized bed reactor (BAS-CT) with hydraulic retention time (HRT) of 0.55 and 0.20 h respectively, in RAS with tilapias with average weight of 0.32 kg and storage density of 33.1 kg.m-3 regarding the removal of total ammonia nitrogen (TAN), biochemical oxygen demand (BOD) and chemical oxygen demand (COD). The removal efficiencies of TAN, BOD and COD were 35.2, 48.0 and 64.9%, respectively. The use of CS with the BAS-CT showed a good performance with low HRT in the treatment of this effluent.

Use of a Process Mass Spectrometer to Measure Rapid Change of Gas Concentration / 分析化学

Experiments were conducted to investigate the suitability of the multistage in-situ reaction analyzer based on a micro fluidized bed ( MFB-MIRA) for measuring the rapid change of the gas concentration during gas-solid reactions. The results showed that the control performance of capillary temperature had a great impact on the stability of on-line measurement. Based on the observed regular patterns, the capillary temperature control system was equipped with a precision temperature controller. The control precision of capillary temperature reached ± 0 . 2℃, which guaranteed the high stabilities of the sampling flow rate and the chamber vacuum. The measured results of the modified gas monitoring system showed the periodic fluctuations of the on-line measurement were eliminated. The stability of measurement was significantly improved. The fluctuating range and relative standard deviation of the measured response to O2 in air changed from 1. 9% and 0. 5% to 1. 4% and 0. 2%, respectively. A pressure regulating device was also developed to control the absolute pressure at the gas sampling point. The control precision reached ± 0. 02 kPa. The measured results showed that the response of the process mass spectrometer was positively correlated with the absolute pressure at the sampling point, indicating the necessity of the pressure regulating device. The accuracy and repeatability of process mass spectrometer were improved. This study has enhanced the suitability of MFB-MIRA for studying rapid gas-solid reactions and broadened the scope of reliable applications of MFB-MIRA and process mass spectrometer.

Precipitação química de estruvita: Recuperação de nutrientes em reator cônico de leito fluidizado utilizando magnésia industrial de baixo custo / Chemical precipitation of struvite: Nutrients recovery in conic fluidized bed reactor using a low-cost industrial magnesia compound

O processo físico-químico da precipitação de estruvita é uma técnica que apresenta elevado potencial na remoção de nutrientes, a partir de diferentes tipologias de efluentes. O presente estudo teve por objetivo a avaliação de um composto industrial com elevado teor de magnésia e baixo custo como fonte reagente alternativa de magnésio e alcalinidade necessários ao processo de precipitação, tornando-o economicamente viável com a redução de gastos despendidos com químicos. Suspensões de Mg(OH)2 foram obtidas e tiveram desempenho avaliado em função da remoção de nutrientes, a partir de um efluente sintético rico em N-NH4+ e P-PO43-, e qualidade dos cristais gerados, com a identificação do mineral de interesse - estruvita. O experimento foi realizado em escala laboratorial utilizando reator cônico de leito fluidizado operado em semi-contínuo. O adequado controle operacional do pH (8,0-8,5) pela adição automatizada da suspensão de Mg(OH)2 possibilitou uma considerável remoção de P-PO43-, que atingiu valor médio igual a 93,5%. Os sólidos recuperados no processo apresentaram pureza de, aproximadamente, 84% de estruvita.

The physico-chemical process of struvite precipitation is a technique that demonstrates a high potential in nutrients recovery from different kinds of wastewaters. This study aimed to evaluate the use of a low cost industrial compound with high magnesia content as alternative reagent source of magnesium ions and alkalinity required for precipitation. It was a strategy to turn the process economically viable and reduce the chemical costs. Mg(OH)2slurries were obtained and evaluated regarding the nutrients recovery from a synthetic wastewater rich in NH4+-N and PO43--P and the quality of the generated crystals with the identification of the mineral of interest - the struvite. The experiment was performed in laboratory scale using a conic fluidized bed reactor in a semi-continuous operation. The proper pH control (8.0-8.5) by the automated addition of Mg(OH)2slurry allowed considerable PO43--P removal equal to 93.5%. The recovered solids from the process showed purity of approximately 84% of struvite.

Preparation and in vitro Dissolution of Pioglitazone Hydrochloride Sustained-release Pellet Capsules / 中国药师

Objective:To prepare pioglitazone hydrochloride ( PGH) sustained-release pellet capsules and study the in vitro disso-lution. Methods:The preparation was prepared with a bottom spray fluidized bed, and the formula and technology were optimized by orthogonal test. Results:The method was simple and easy to operate, the reproducibility of the formula and technology was good, and the pellets had obvious sustained-release property. Conclusion:The formula and technology are easy and controllable, and the stability of sustained release pellets is good.

Evaluation of fluidized granulation technology of Jianwei Xiaoshi Tablet by multicriteria synthesizing grading method / 中草药

Objective: To explore the feasibility of multicriteria synthesizing grading method using in the optimization of the fluidized granulation technology for Jianwei Xiaoshi Tablet (JXT), and to provide a reference for fluidized granulation technology to spread and apply in the pelletization of materials with strong stickiness. Methods: Using orthogonal design, the property parameters of granule and tablet were measured, and the best process parameters were optimized. Results: The optimal process parameters were as follows: The inlet air temperature was 55°C, the inlet pressure was 8 kPa, the spray pressure was 30 kPa, and the flow rate of the liquid was 1.0-2.5 mL/min. Conclusion: The multicriteria synthesizing grading method used in optimizing the fluidized granulation technology of JXT is stable and feasible, and provides theory evidence for improving the productivity and product quality.

Preparation and quality evaluation of ibuprofen sustained release pellet capsules based on solid dispersion technology / 中国药学杂志

OBJECTIVE: To prepare ibuprofen sustained release pellet capsules based on solid dispersion technology and evaluate the quality. METHODS: Ibuprofen matrix sustained release pellets were prepared by fluidized-bed spray drying process, using blank pill core as based pills, stearic acid as isolation layer, and PVP as carrier material. The factors influencing the pellet release were studied, including coating dispersion, preparation method, and assay method of release. RESULTS: The prepared ibuprofen sustained release pellets had ideal controlled release and characteristics, including particle size, spherical degree, drug loading, and content. CONCLUSION: A new preparation method of ibuprofen sustained release pellets with advantages of less adjuvants, no deed to micronize crude drug, simple process, and controllable quality is successfully developed. It can be used in industrialized manufacture.

Formulation and characterization of immediate-release itraconazole-loaded pellets prepared by fluidized bed spray coating / 中国药学杂志

OBJECTIVE: To develop immediate-released itraconazole-loaded pellets prepared by fluidized bed spray coating. METHODS: With common hydrophilic excipients(HPMC E5, PVP K30, PEG6000, and Poloxamer 188) as the carrier material, solid dispersion solution(dichloromethane-ethanol, 1: 1, V/V) containing water-insoluble itraconazole was prepared, and then was sprayed on the surface of the sugar cores in fluidized bed to directly form immediate-reaease drug-loaded pellets containing itraconazole solid dispersion. Subsequently, its drug dissolution, crystal characterization, appearance, and residual solvent were evaluated. RESULTS: The obtained pellets are clean and beautiful appearance. And itraconazole in the drug-loaded layer exists in amorphous or molecular state, meets with the solid dispersion structure. It was interesting that, the pellets containing HPMC E5/itraconazole(1.5: 1, w/w) solid dispersion were of rapid drug dissolution(15 min up to 80%). To ensure that residual solvent within the limits, it was necessary that the obtained pellets were dried more than 6 h at 80°C in vacuum. CONCLUSION: It is feasible that immediate-release itraconazole-loaded pellets are prepared by fluidized bed spray coating technology, and its quality could be controlled. Copyright 2013 by the Chinese Pharmaceutical Association.

Functionality advancement of poorly soluble biovariable anti hypertensive Drug by sophisticated SD-FBP technology as per enhanced QbD.

Lacidipine (LCDP) is a dihydropyridine derivative categorized as an Anti-hypertensive Ca+2 channel blocker belonging to BCS class IV drug with low solubility and low permeability which presents a challenge to the formulation scientists. The development of a solid dispersion by solvent evaporation is a practically viable method to enhance dissolution of LCDP from oral dosage form. Solvent evaporation by Fluidized Bed Process (FBP) was the method of choice for SD as it improves wettability with simultaneous increase in porosity of granules resulting enhanced surface area producing higher dissolution rate and bioavailability of poorly water-soluble drug. Thus, the main object of the present invention is to provide stable pharmaceutical dosage form of LCDP with desired dissolution rate i.e. at least 80% drug release within 45 minutes, without use of disintegrant(s) and/or surfactant(s) or without micronization of the active ingredient per se. One more object of this invention is to provide a sophisticated robust process for the preparation of said pharmaceutical dosage form by Quality by Design (QbD) concept focusing on thorough understanding of the product and process by which it is developed and manufactured along with a knowledge of the risks involved in manufacturing by IRMA & FMEA study of the product with process and how best to mitigate those risks by developing design space with DoE & MVDA with outlined control strategy.

Ammonia removal in a water recirculating system for tilapia using an aerobic three-phase fluidized-bed reactor / Monitoramento de 24 horas do desempenho de reator aeróbio de leito fluidizado trifásico na remoção de amônio num sistema de recirculação para produção de tilápia / Remoción de amonio en un sistema de recirculación de agua para tilapia mediante un reactor aerobio de lecho fluidizado trifásico

The main objective of this study was to evaluate the ammonia removal efficiency in the wastewater treatment system of an intensive tilapia laboratory production system with water recirculation. The system comprised of a conventional sedimentation basin and an aerobic three-phase fluidized-bed reactor with circulation, operated at hydraulic detention times of 176.4 and 11.9 minutes respectively. Granular activated carbon was used as carrier with apparent density of 1.64 g/cm³ and effective size of 0.34 mm; the carrier concentration into the reactor was maintained constant at 80 g/L. Mean removal efficiency of total ammonia nitrogen was 41.2%. The evaluated system is an effective option for water reuse in aquaculture recirculating systems. In spite of ammonium nitrogen concentration variability which average value was 0.136 mg/L, the reactor influent maintained water quality characteristics in stable conditions, with average concentrations of ammonia nitrogen of 0.079 mg/L and dissolved oxygen concentration of 6.70 mg/L, recommended for fish culture and within the permitted values by the Brazilian legislation (CONAMA Resolution No. 357 of march 5 of 2005) for the disposal of final effluent in receiving water bodies.

O objetivo deste trabalho foi monitorar o desempenho de remoção de nitrogênio amoniacal no tratamento das águas residuárias da produção intensiva de tilápia nilótica em sistema com recirculação de água. O sistema foi constituído por um sedimentador convencional e um reator aeróbio de leito fluidizado trifásico com circulação, operados com tempos de detenção hidráulica de 176.4 e 11.9 minutos respectivamente. O meio suporte utilizado no reator foi o carvão ativado granular com densidade aparente de 1.64 g/cm³ e tamanho efetivo de 0.34 mm; a concentração do meio suporte no reator foi mantida constante em 80 g/L. A eficiência média de remoção do nitrogênio amoniacal total foi de 41.2%. O sistema avaliado é uma alternativa efetiva para o reuso da água em sistemas de recirculação para aqüicultura. Embora a variabilidade das concentrações do nitrogênio amoniacal afluente cujo valor médio foi de 0.136 mg/L, o efluente do reator conservou as características de qualidade da água estáveis, com concentrações médias de nitrogênio amoniacal de 0.079 mg/L e do oxigênio dissolvido de 6.70 mg/L, recomendáveis para a criação dos peixes e nas faixas de valores permitidos pela legislação Brasileira (Resolução CONAMA No. 357 de março 5 de 2005) para lançamento de efluentes finais nos corpos de água receptores.

El objetivo de este trabajo fue monitorear el desempeño de remoción de nitrógeno amoniacal en el tratamiento de las aguas residuales de producción intensiva de tilapia nilótica en un sistema con recirculación de agua. El sistema estuvo constituido por un sedimentador convencional y un reactor aerobio de lecho fluidizado trifásico con circulación, operados con tiempos de retención hidráulica de 176.4 y 11.9 minutos, respectivamente. El medio soporte utilizado en el reactor fue carbón activado granular con densidad aparente de 1.64 g/cm³ y tamaño efectivo de 0.34 mm; la concentración del medio soporte en el reactor se mantuvo constante en 80 g/L. La eficiencia media de remoción del nitrógeno amoniacal total fue de 41.2%. El sistema evaluado es una alternativa efectiva para el reuso del agua en sistemas de recirculación para acuicultura. Pese a la variabilidad de las concentraciones de nitrógeno amoniacal afluente cuyo valor promedio fue de 0.136 mg/L, el efluente del reactor mantuvo las características de calidad del agua en condiciones estables, con concentraciones promedio de nitrógeno amoniacal de 0.079 mg/L y de oxígeno disuelto de 6.70 mg/L, recomendables para el cultivo de los peces y en los valores permitidos por la legislación Brasilera (Resolución CONAMA No. 357 de marzo 5 de 2005) para lanzamiento de efluentes finales en cuerpos de agua receptores.

Transferência de oxigênio em reatores de leito fluidizado com circulação em tubos concêntricos em meios bifásico e trifásico com variação da relação entre diâmetros / Oxygen transfer in two and three-phase internal-loop airlift reactor with riser diameter variation

A eficiência do reator de leito fluidizado com circulação em tubos concêntricos depende das condições hidrodinâmicas que influem na transferência de oxigênio ao biofilme. Este trabalho investigou a influência da relação entre diâmetros dos tubos e da concentração de meio suporte (areia), sobre o coeficiente global de transferência de oxigênio (K La). Os ensaios - em reatores de 2,6 m de altura, com diâmetro externo de 250 mm e internos de 100, 125, 150 e 200 mm - empregaram vazões de ar até 2.500 L.h-1 e concentrações de até 150 g.L-1 de areia. O K La aumentou ligeiramente com 30 g.L-1 e diminuiu para concentrações maiores, confirmando relatos da literatura em condições semelhantes. Um modelo para K La em meio bifásico foi ajustado para as diversas relações ensaiadas entre a área externa e a interna, postulando-se uma redução na razão entre a transferência na fase líquida e o diâmetro da bolha com o aumento da vazão de ar.

The efficiency of the concentric tubes internal-loop airlift reactor depends on the hydrodynamic conditions that affect oxygen transfer to the biofilm. This work studied the effects of the relation between diameters of the tubes and of the carrier (sand) concentration on the global oxygen transfer coefficient (K La). The tests - in 2,6 m high reactors with 250 mm external diameter and 100, 125, 150 and 200 mm internal diameters - were performed with air flow taxes up to 2,500 L.h-1 and sand concentrations up to 150 g.L-1. The K La increased slightly for 30 g.L-1 and decreased for higher concentrations, in accordance with related data for similar conditions. A model for K La in biphasic medium was fitted embracing all the external/internal area relationships tested, based on the reduction of the liquid phase transfer coefficient and the bubble diameter ratio with increasing air flow rates.