7 research outputs found
Theoretical, Manufacturing and Clinical Application Aspects of a Prostate Brachytherapy I-125 Source in Brazil
Developing an electrical power system of a mobile electron beam accelerator to treat wastewater and industrial effluents / Desenvolvimento de um sistema de energia elétrica de um acelerador móvel de feixe de elétrons para tratar águas residuais e efluentes industriais
The treatment of wastewater and industrial effluents by electron beam irradiation is a promising technique, however, not very widespread in Brazilian territory. The design and construction of a mobile unit by the Nuclear and Energy Research Institute, containing an electron beam accelerator of 700 keV and 20 kW is innovative to demonstrate the effects and positive results of this technology. The aim is to transfer the mobile unit to several companies with interest in liquid waste treatment, connect to the industry electrical system and start the ionization treatment process through electron beam. The mobile unit connection to the local electrical system may be a challenge due to the great diversity of voltages and distances involved, as well as the large injections of harmonic content generated by the electron beam accelerator that can affect sensitive loads in the industrial system. In this work, an analysis of the electrical power system of the mobile unit was made, regarding the interruption capacity, selectivity protection and adequate short circuit levels, in order to assure a greater reliability in the operation. At the end, the control panel of the mobile unit, simulations and measurements were carried out at the 1.5 MeV and 37.5 kW electron beam accelerator, installed in the Radiation Technology Center, demonstrating the necessity of applying a filter to reduce the measured harmonic distortion. The analysis of the mobile unit electrical power system was made, in order to assure a greater reliability in the operation.
Automated system development for operating control for a Cockcroft-Walton industrial electron beam accelerator
Os aceleradores de feixes de elétrons são utiizados em muitas aplicações, tais como pesquisa em física básica, química, medicina, biologia molecular, microeletrônica, agricultura e indústria, dentre outras. Na maioria dos aceleradores, por meio de aquecimento do filamento de tungstênio e da alta tensão via gerador Cockcroft-Walton, os elétrons passam por um campo elétrico na câmara em vácuo e são acelerados de acordo com a alta tensão aplicada, transferindo energia aos elétrons. Para fins industriais, um dos equipamentos mais utilizados é o Acelerador Industrial de Elétrons Dynamitron®. No IPEN-CNEN/ SP, instalou-se um acelerador de feixe de elétrons Dynamitron®, fabricado pela RDI Radiation Dynamics Inc., modelo DC1500/25/4, em 1978. A tecnologia analógica aplicada nesse acelerador industrial de elétrons data de 1960 e 1970. Assim, além da tecnologia de controle operacional obsoleta, não há mais peças e componentes sobressalentes originais, fornecidos pelo fabricante (RDI) ao equipamento. O objetivo deste trabalho foi desenvolvido um sistema automatizado para controle operacional do acelerador industrial de elétrons Cockcroft-Walton de 37,5 kW (1,5 MeV e 25 mA) no Instituto.Electron beam accelerators are used in many applications, such as basic research in physics, chemistry, medicine, molecular biology, microelectronics, agriculture and industry, among others. In most accelerators, by means of heating a tungsten filament and high-voltage from a CockcroftWalton generators, the electrons go through an electrical field in the vacuum chamber and are accelerated according to the high-voltage applied to transferring energy to the electrons. For industrial purposes, one of the most used of equipment is the Dynamitron® Industrial Electron Beam Accelerator. In IPEN-CNEN/SP, this Dynamitron® Accelerator, manufactured by RDI - Radiation Dynamics Inc, model DC1500/25/4, was installed, in 1978. The analogical technology applied in this industrial accelerator dates from 1960 and 1970. Therefore, besides the obsolete operational control technology, there are not spare parts or components supplied by the manufacturer (RDI).The goal of this work was to develop an automated system for the operational control of the Cockroft-Walton industrial electrons accelerator of 37.5 kW (1.5 MeV and 25 mA), at IPEN-CNEN/SP
Development of an automation system for iodine-125 brachytherapy seed production by (Nd:YAG) laser welding
O objetivo deste trabalho é desenvolver um sistema de automação para a produção das sementes de iodo-125 por soldagem a laser (Nd:YAG). As sementes de iodo- 125 são utilizadas com sucesso no tratamento de câncer por braquiterapia, via baixa taxa de dose. Esta pequena semente é constituída por uma cápsula de titânio soldada, com 0,8mm de diâmetro e 4,5mm de comprimento, contendo iodo-125 adsorvido em fio de prata, no interior da mesma. As sementes de iodo-125 são implantadas na próstata humana para irradiar o tumor e tratar o câncer. Hoje, o Centro de Tecnologia das Radiações - CTR, do IPEN-CNEN/SP importa e distribui 36.000 sementes de iodo-125 por ano, para as clínicas e hospitais no País. No entanto, o potencial do mercado brasileiro é de 8.000 sementes de iodo-125 por mês. Assim, a produção local destas fontes radioativas de iodo- 125 tornou-se uma prioridade para o Instituto, visando reduzir o preço e aumentar o fornecimento à população. Por outro lado, a automação industrial desempenha papel importante na fabricação das sementes de iodo-125, com aumento da produtividade e padrão elevado de qualidade, além de facilitar a implementação e o funcionamento de processos com Boas Práticas de Fabricação (BPF). A tecnologia consiste em associar peças mecânicas e componentes eletro-eletrônicos, para controle de máquinas e processos. A tecnologia de automação para produção das sementes de iodo-125 desenvolvida neste trabalho emprega Controlador Lógico Programável (CLP), motores de passos, drivers, máquina de soldagem a laser (Nd:YAG), sensores fotoelétricos e interfaces de comunicação.The aim of this work is to develop an automation system for iodine-125 radioactive seed production by (Nd:YAG) laser welding, which has been used successfully in Low Dose Rate (LDR) brachytherapy treatment. This small seed consists of a welded titanium capsule, with 0.8mm in diameter and 4.5mm in length, containing iodine-125 adsorbed onto a silver rod. The iodine-125 seeds are implanted into the human prostate to irradiate the tumor for cancer treatment. Nowadays, the Radiation Technology Center, at IPEN-CNEN/SP imports and distributes 36,000 iodine-125 seeds per year, for the clinics and hospitals in the country. However, the Brazilian market potential is now over 8,000 iodine-125 seeds per month. The local production of these iodine-125 radioactive sources becomes a priority for the Institute, in order to reduce the price and the problems of prostate cancer management. It will permit to spread their use to a largest number of patients in Brazil. On the other hand, the industrial automation plays an important role for iodine-125 seeds in order to increase the productivity, with high quality and assurance, avoiding human factors, implementing and operating with Good Manufacturing Practices (GMP). The technology consists of appliance electronic and electro-mechanical parts and components to control machines and processes. The automation system technology for iodine-125 seed production developed in this work was mainly assembled employing Programmable Logic Controller (PLC), stepper motors, drivers, (Nd:YAG) laser welding machine, photoelectric sensors and supervisory
Automated system development for operating control for a Cockcroft-Walton industrial electron beam accelerator
Os aceleradores de feixes de elétrons são utiizados em muitas aplicações, tais como pesquisa em física básica, química, medicina, biologia molecular, microeletrônica, agricultura e indústria, dentre outras. Na maioria dos aceleradores, por meio de aquecimento do filamento de tungstênio e da alta tensão via gerador Cockcroft-Walton, os elétrons passam por um campo elétrico na câmara em vácuo e são acelerados de acordo com a alta tensão aplicada, transferindo energia aos elétrons. Para fins industriais, um dos equipamentos mais utilizados é o Acelerador Industrial de Elétrons Dynamitron®. No IPEN-CNEN/ SP, instalou-se um acelerador de feixe de elétrons Dynamitron®, fabricado pela RDI Radiation Dynamics Inc., modelo DC1500/25/4, em 1978. A tecnologia analógica aplicada nesse acelerador industrial de elétrons data de 1960 e 1970. Assim, além da tecnologia de controle operacional obsoleta, não há mais peças e componentes sobressalentes originais, fornecidos pelo fabricante (RDI) ao equipamento. O objetivo deste trabalho foi desenvolvido um sistema automatizado para controle operacional do acelerador industrial de elétrons Cockcroft-Walton de 37,5 kW (1,5 MeV e 25 mA) no Instituto.Electron beam accelerators are used in many applications, such as basic research in physics, chemistry, medicine, molecular biology, microelectronics, agriculture and industry, among others. In most accelerators, by means of heating a tungsten filament and high-voltage from a CockcroftWalton generators, the electrons go through an electrical field in the vacuum chamber and are accelerated according to the high-voltage applied to transferring energy to the electrons. For industrial purposes, one of the most used of equipment is the Dynamitron® Industrial Electron Beam Accelerator. In IPEN-CNEN/SP, this Dynamitron® Accelerator, manufactured by RDI - Radiation Dynamics Inc, model DC1500/25/4, was installed, in 1978. The analogical technology applied in this industrial accelerator dates from 1960 and 1970. Therefore, besides the obsolete operational control technology, there are not spare parts or components supplied by the manufacturer (RDI).The goal of this work was to develop an automated system for the operational control of the Cockroft-Walton industrial electrons accelerator of 37.5 kW (1.5 MeV and 25 mA), at IPEN-CNEN/SP
A study about the measurement method of the homogeneity of radioactivity along an iridium-192 wire used in brachytherapy
The Nuclear and Energy Research Institute has produced, since 1998, iridium-192 wires used in low dose rate brachytherapy. In the paper the authors studied the influence of wire profile on the homogeneity distribution of radioactivity of iridium-192 along the wire. The authors propose the improvements in the quality control procedure that will provide more accurate measurement data and suggest changes in control devices
Integration of Corn and Cane for Ethanol Production: Effects of Lactobacilli Contamination on Fermentative Parameters and Use of Ionizing Radiation Treatment for Disinfection
Recently, in Brazil, corn ethanol industries are being installed and the integration with sugar/energy-cane has been proposed, using bagasse for cogeneration and the juice to dilute the corn. However, this integration may have some limitations, such as the quality of the cane juice and potential contamination by microorganisms brought with the cane from the field. In this article, we first tested the effects of mixing energy cane juice with corn on fermentative parameters. We also assessed the effects of Lactobacilli. contamination on organic acids produced during the fermentation and fermentation parameters and proposed the use of ionizing radiation to replace antibiotics as a disinfection control method. Our results showed that mixing energy cane juice with corn does not have any negative effect on fermentation parameters, including ethanol production. The contamination with Lactobacilli. considerably increased the production of acetic, lactic, and succinic acid, reducing the pH and ethanol content from 89.2 g L−1 in the sterilized treatment to 72.9 g L−1 in the contaminated treatment. Therefore, for the integration between corn and cane to be applied on an industrial scale, it is essential to have effective disinfection before fermentation. Ionizing radiation (20 kGy) virtually disinfected the wort, showing itself to be a promising technology; however, an economic viability study for adopting it in the industry should be carried out