Design of a thermochemical heat storage system for tap water heating in the built environment

Replacing the use of fossil fuel by solar energy, as one of the most promising sustainable energy sources, is of high interest, because of climate change and depletion of fossil resources. However, to reach high solar fractions and to overcome the mismatch between supply and demand of solar heat, storage of solar energy is necessary. A reliable method for long term heat storage is to use thermochemical materials, TCMs. The heat storage process is based on a reversible adsorption-desorption reaction of water vapor on the TCM, which is exothermic in one direction and endothermic in the reverse direction. In this research, Zeolite 13X is used as TCM. The system is an open sorption heat storage system for providing hot tap water. In the experimental test setup, the humid air is provided in a bubble column by blowing air from bottom of the column. The exothermic hydration process starts with humid air entering into a packed bed reactor filled with zeolite 13X. The reactor is a vertical cylindrical tank which is made of steel; it has a layer of Teflon inside and has a layer of insulation outside. The temperature profile in the reactor is measured as a function of time both along the flow direction and perpendicular to the flow by thermocouples. In addition, input and output temperatures and humidity are measured. In the resulting adsorption reaction between water vapor and TCM, energy is released. This released energy heats up the air flow which passes through the reactor and the hot output air flow is used to heat up the water in a water tank. The water tank is also a vertical cylindrical tank which is made of steel and has a layer of insulation outside. The hot output air from the reactor passes through a coiled tubing inside the water tank to heat up water. The temperature of the water in the tank is measured at two different heights. A problem in open solid sorption systems using air as heat transport medium is the limited temperature step which can be achieved in the sorption bed. In the present study this problem is solved using a heat recovery system enabling higher output air temperatures. The residual heat in the exhaust air is used to preheat the reactor inflow, in an air-to-air heat exchanger. In the endothermic dehydration process, the hydrated zeolite is dried with hot air. In this study, a lab-scale prototype TCM based heat storage system is designed and optimized, which, by making use of a heat recovery loop, is able to provide hot tap water. Results of the experimental investigation on charge-discharge cycles will be presented.<br/

Toelichting: influenza 1994/1995: een carnavalsstorm in een glas bier.

Tot eind februari leek het influenzaseizoen 1994/1995 uitzonderlijk rustig te verlopen. De peilstations van NIVEL (Nederlands Instituut voor onderzoek van de gezondheidszorg) meldden week na week dat er niets viel te melden. Het Nationaal Influenza Centrum in Bilthoven en Rotterdam noteerden sporadische virusisolanten, overwegend van type B. Rond carnaval echter leek dit beeld te veranderen. In drie achtereenvolgende weken verdubbelden telkens in de regio Zuid (Zeeland, Noord-Brabant en Limburg) het aantal bij NIVEL gerapporteerde influenza-achtige ziektegevallen (IAZ) van 5 op de 10.000 inwoners in week 7 tot 43 in week 10. (aut. ref.

Influenza A/H3N2 epidemie in Nederland.

In een grafiek wordt het verloop getoond van een influenza-epidemie aan de hand van de registratie van influenza-achtige ziektebeelden (IAZ) die door het NIVEL gecoördineerd wordt. (aut. ref.

A pandemic warning?

Lette

Infection of children with avian-human reassortant influenza virus from pigs in Europe

Pigs have been proposed to act as the intermediate hosts in the generation of pandemic human influenza strains by reassortment of genes from avian and human influenza virus strains. The circulation of avian-like H1N1 influenza viruses in European pigs since 1979 and the detection of human-avian reassortants in pigs raises the question of whether these viruses actually have the potential to transmit and cause disease in humans. We now report the serologic and genetic characterization of two human influenza A viruses (A/Netherlands/5/93 [H3N2] and A/Netherlands/35/93 [H3N2]) that caused influenza in children in The Netherlands in 1993. The results show that these viruses are human-avian reassortants that were generated and currently still are circulating in European swine. This shows the pivotal role that pigs can play in the generation and transmission of avian influenza virus genes to humans and their potential to generate a new human pandemic strain

Antigenic and genetic characterization of swine influenza A (H1N1) viruses isolated from pneumonia patients in The Netherlands.

It is generally believed that pigs can serve as an intermediate host for the transmission of avian influenza viruses to humans or as mixing vessels for the generation of avian-

Antigenic drift in swine influenza H3 haemagglutinins with implications for vaccination policy

In order to explore the occurrence of antigenic drift in swine influenza A(H3N2) virus, we examined virus strains from outbreaks of respiratory disease among finishing pigs in the Netherlands in 1996 and 1997 and from earlier outbreaks. In contrast to swine H3N2 strains from the 1980s, the recent isolates did not show significant cross-reactivity with human influenza A(H3N2) viruses from 1972-1975 in haemagglutination inhibition tests. These new strains form a separate branch in the phylogenetic tree of the HA1 parts of HA. We conclude that recently there has been considerable antigenic drift within the swine H3N2 viruses in the Netherlands and Belgium and recommend replacement of the A/Port Chalmers/1/73 (H3N2) strain in the current vaccine by a more recent swine H3N2 isolate

Antigenic drift in swine influenza H3 haemagglutinins with implications for vaccination policy

In order to explore the occurrence of antigenic drift in swine influenza A(H3N2) virus, we examined virus strains from outbreaks of respiratory disease among finishing pigs in the Netherlands in 1996 and 1997 and from earlier outbreaks. In contrast to swine H3N2 strains from the 1980s, the recent isolates did not show significant cross-reactivity with human influenza A(H3N2) viruses from 1972-1975 in haemagglutination inhibition tests. These new strains form a separate branch in the phylogenetic tree of the HA1 parts of HA. We conclude that recently there has been considerable antigenic drift within the swine H3N2 viruses in the Netherlands and Belgium and recommend replacement of the A/Port Chalmers/1/73 (H3N2) strain in the current vaccine by a more recent swine H3N2 isolate