833 resultados para CHP
Resumo:
Työn tavoitteena on pienitehoisen CHP-laitoksen verkkoonliitynnän suunnittelu. Laitos polttaa Einco Oy:n CFB-kuivurissa (Circulating fluidized-bed) termisesti kuivattua lietettä hönkäkaasujen kanssa Einco Oy:n CTC-reaktorissa (Constant temperature combustion). CFB-kuivuri ja CTC-reaktori on kytketty höyryvoimalaitosprosessiin, jonka turbogeneraattorista saadaan sähköenergiaa. Työssä on tutkittu nykypäivän hajautetun tuotannon pienvoimalaitoksen verkkoonliitynnän suojausvaatimuksia, sähkönlaatuvaatimuksia, suosituksia ja mahdollisen verkonhaltijan ohjeita sekä generaattorilaitteistojen ominaisuuksia. Generaattorilaitteistot ovat vierasmagnetoitu tahtigeneraattori tai itsemagnetoitu tahtigeneraattori, kestomagneettitahtigeneraattori tai verkkomagnetoitu epätahtigeneraattori. Lisäksi on tarkasteltu ja vertailtu generaattorilaitteistojen verkkoonliitynnässä tarvittavien eri automaatiolaitteiden ominaisuuksia. Verkkoonliitynnät on suunniteltu 400 kW generaattorilaitteistovaihtoehdoille kahdella tavalla: suoraan verkkoon kytkettynä ja taajuusmuuttajalla verkkoon kytkettynä. Työn päätuloksia ovat suunnitellut sähköliittymät sekä suojaus- ja ohjauspiirit, ensiö- ja toisiosuojaukset, toteutustason piirustukset ja automaation toimintaselostus. Lisäksi suunnitelluille automaatiokokoonpanoille on laskettu hankintakustannukset. Taajuusmuuttajan avulla verkkoon kytketty suoravetoturbogeneraattori on todettu teknisesti ja taloudellisesti toimivaksi.
Resumo:
Maapallon ilmasto lämpenee koko ajan kasvihuonekaasujen määrän lisääntyessä ilmakehässä. Merkittävin ihmisten aiheuttama päästöjen lähde on fossiilisten polttoaineiden käyttö energiantuotannossa ja liikenteessä, jonka vuoksi on tärkeää lisätä uusiutuvien energialähteiden käyttöä. Tämän diplomityön tavoitteena oli selvittää esimerkkialueena olevan maaseutuyhteiskunnan mahdollisuutta olla energiaomavarainen ja materiaalikierroiltaan suljettu, jos alueen tarvitsema sähkö ja lämpö tuotettaisiin paikallisilla biomassavaroilla kahdella rinnakkaisella pienen mittakaavan CHP-laitoksella. Tarkastellut laitokset olivat anaerobisen mädätyksen ja polttokennojen yhdistelmä sekä termisen käsittelyn ja ORC-prosessin yhdistelmä. Työssä tehdyt laskelmat osoittivat, että esimerkkialue saisi tuotettua omilla biomassavaroillaan tarvitsemastaan sähköstä 75 % ja lämmöstä 90 % esimerkkilaitosten avulla. Laskelmissa ei kuitenkaan huomioitu kesä- ja talvikuukausien välistä eroa lämmön kulutuksessa, jonka vuoksi molemmat laitokset eivät voisi toimia koko ajan täydellä teholla. Lisäksi tuotetun lämmön hyötykäyttöä rajoittaa riittävän laajan kaukolämpöverkon puuttuminen esimerkkialueelta. Nykyisen kaukolämpöverkon avulla saataisiin hyödynnettyä vain kolmasosa ORC-prosessilla tuotetusta lämpöenergiasta. Laskelmat osoittivat myös, että alueen kasvihuonekaasupäästöt pienenisivät 21 % eli noin 6 000 hiilidioksidiekvivalenttitonnia vuodessa, jos suurin osa energiasta tuotettaisiin omista biomassavaroista CHP-laitosten avulla ja mädätyksen seurauksena syntyvä reaktorijäännös korvaisi kemiallisten lannoitteiden käytön.
Resumo:
This thesis is a preliminary study targeting South-Eastern Finland. The objective was to find out the financial and functional readiness and willingness of the small and medium-sized enterprises of the region to manufacture and sell distributed bioenergy solutions collaboratively as a business network. In this case these solutions mean small-scale (0.5 - 3 MW) woodchips-operated combined heat and power (CHP) plants. South-Eastern Finland has suffered from a decline in the recent years, mostly due to the problems of the traditionally strong industrial know-how area of the region, the paper industry. Local small and medium-sized companies will have to find new ways to survive the toughening competition. A group of 40 companies from suitable industries were selected and financial and comparative analysis was performed on them. Additionally 19 managing directors of the companies were selected for an interview to find out their views on networking, its requirements, advantages and the general interest in it. The studied companies were found to be generally in fairly good financial condition and in that sense, fit for networking activities. The interviews revealed that the companies were capable of producing all the needed elements for the plants in question, and the managers appeared to be very interested in and have a positive attitude towards such business networks. Thus it can be said that the small and medium-sized companies of the region are capable of and interested in manufacturing small bio-CHP plants as a production network.
Resumo:
Fossiiliset polttoainevarannot ovat ehtymässä. Nykyisen talouskasvumme perustuessa fossiilisten polttoaineiden kestämättömään käyttöön, on energiantuotantorakenteen muututtava. Euroopan Unioni on asettanut tavoitteet uusiutuvan energian osuuden lisäämiseksi. Näistä syistä johtuen kiinnostus uusiutuvaa energiaa ja hajautettua energiantuotantoa kohtaan on kasvanut viime aikoina. Tämän globaalin ilmiön rinnalla yhteiskuntarakenteen muutos Suomessa on johtanut tilanteeseen, jossa taloudellinen aktiviteetti kasvukeskusten ulkopuolella on hiipumassa. Loogisena ratkaisumallina on syntynyt hankkeita kuten Keski-Karjalan Kehitysyhtiö Oy:n Puhos 2013 - ympäristöalasta uutta liiketoimintaa - hanke. Tämä työ on Puhos 2013 - hankkeeseen tilattu tutkimus, jonka tavoitteena on puuta ja biokaasua polttoaineenaan käyttävän mikroturbiinitekniikkaan pohjautuvan pienen kokoluokan CHP tuotannon kannattavuuden selvittäminen kunnallisen lämpölaitoksen yhteydessä. Tutkimuksessa selvitettiin aluksi pienen kokoluokan CHP tuotannon kannattavuuteen vaikuttavat tekijät, jonka jälkeen opittua tietoa sovellettiin Kiteen Lämmön Arppentien lämpölaitoksen tapaukseen. Kiteen Lämmön taloudellisen kannattavuuden ohella tutkimuksessa huomioitiin uusien liiketoiminta mahdollisuuksien syntyminen alueelle. Käytetyt tutkimusmenetelmät olivat kvalitatiivinen analyysi ja perinteinen investoinnin kannattavuuslaskenta. Tutkimuksen tuloksena muodostettiin strategia, joka maksimoi molemmat edellä mainitut kannattavuuden näkökulmat. Kehitetyn strategian Kiteen Lämmön tulosta maksimoiva osuus muodostuu oman käyttösähkön tuottamisen aloittamisesta Arppentien lämpölaitoksella 30 kWe mikroturbiinilla käyttäen polttoaineena Bio10 Oy:n toimittamaa biokaasua. Uusien liiketoiminta mahdollisuuksien synty alueelle mahdollistetaan puolestaan kehittämällä puun kaasutukseen perustuva modulaarinen CHP laitos yhteistyössä Mekrijärven tutkimusaseman ja suomalaisten laitevalmistajien kanssa.
Resumo:
All over the world power systems become bigger and bigger every day. New equipment is installed, new feeders are constructed, new power units are installed. Some old elements of the network, however, are not changed in time. As a result, “bottlenecks” for capacity transmission can occur. By locked power problem the situation when a power plant has installed capacity exceeding the power it can actually deliver is usually meant. Regime, scheme or even technical restrictions-related issues usually cause this kind of problem. It is really important, since from the regime point of view it is typical decision to have a mobile capacity reserve, in case of malfunctions. And, what can be even more significant, power plant owner (JSC Fortum in our case) losses his money because of selling less electrical energy. The goal of master`s thesis is to analyze the current state of Chelyabinsk power system and the CHP-3 (Combined Heat and Power plant) in particular in relation with it`s ability to deliver the whole capacity of the CHP in it`s existing state and also taking into consideration the prospect of power unit 3 installation by the fourth quarter of 2010. The thesis contains some general information about the UPS of Russia, CPS of Ural, power system of Chelyabinsk and the Chelyabinsk region itself. Then the CHP-3 is described from technical point of view with it`s equipment observation. Regimes for the nowadays power system and for the system after the power unit 3 installation are reviewed. The problems occurring are described and, finally, a solution is offered.
Resumo:
This letter has tested the canopy height profile (CHP) methodology as a way of effective leaf area index (LAIe) and vertical vegetation profile retrieval at a single-tree level. Waveform and discrete airborne LiDAR data from six swaths, as well as from the combined data of six swaths, were used to extract the LAIe of a single live Callitris glaucophylla tree. LAIe was extracted from raw waveform as an intermediate step in the CHP methodology, with two different vegetation-ground reflectance ratios. Discrete point LAIe estimates were derived from the gap probability using the following: 1) single ground returns and 2) all ground returns. LiDAR LAIe retrievals were subsequently compared to hemispherical photography estimates, yielding mean values within ±7% of the latter, depending on the method used. The CHP of a single dead Callitris glaucophylla tree, representing the distribution of vegetation material, was verified with a field profile manually reconstructed from convergent photographs taken with a fixed-focal-length camera. A binwise comparison of the two profiles showed very high correlation between the data reaching R2 of 0.86 for the CHP from combined swaths. Using a study-area-adjusted reflectance ratio improved the correlation between the profiles, but only marginally in comparison to using an arbitrary ratio of 0.5 for the laser wavelength of 1550 nm.
Resumo:
This paper presents an open-source canopy height profile (CHP) toolkit designed for processing small-footprint full-waveform LiDAR data to obtain the estimates of effective leaf area index (LAIe) and CHPs. The use of the toolkit is presented with a case study of LAIe estimation in discontinuous-canopy fruit plantations. The experiments are carried out in two study areas, namely, orange and almond plantations, with different percentages of canopy cover (48% and 40%, respectively). For comparison, two commonly used discrete-point LAIe estimation methods are also tested. The LiDAR LAIe values are first computed for each of the sites and each method as a whole, providing “apparent” site-level LAIe, which disregards the discontinuity of the plantations’ canopies. Since the toolkit allows for the calculation of the study area LAIe at different spatial scales, between-tree-level clumpingcan be easily accounted for and is then used to illustrate the impact of the discontinuity of canopy cover on LAIe retrieval. The LiDAR LAIe estimates are therefore computed at smaller scales as a mean of LAIe in various grid-cell sizes, providing estimates of “actual” site-level LAIe. Subsequently, the LiDAR LAIe results are compared with theoretical models of “apparent” LAIe versus “actual” LAIe, based on known percent canopy cover in each site. The comparison of those models to LiDAR LAIe derived from the smallest grid-cell sizes against the estimates of LAIe for the whole site has shown that the LAIe estimates obtained from the CHP toolkit provided values that are closest to those of theoretical models.
Resumo:
Xylella fastidiosa is an important phytopathogenic bacterium that causes many serious plant diseases, including Pierce`s disease of grapevines. Disease manifestation by X. fastidiosa is associated with the expression of several factors, including the type IV pili that are required for twitching motility. We provide evidence that an operon, named Pil-Chp, with genes homologous to those found in chemotaxis systems, regulates twitching motility. Transposon insertion into the pilL gene of the operon resulted in loss of twitching motility (pilL is homologous to cheA genes encoding kinases). The X. fastidiosa mutant maintained the type IV pili, indicating that the disrupted pilL or downstream operon genes are involved in pili function, and not biogenesis. The mutated X. fastidiosa produced less biofilm than wild-type cells, indicating that the operon contributes to biofilm formation. Finally, in planta the mutant produced delayed and less severe disease, indicating that the Pil-Chp operon contributes to the virulence of X. fastidiosa, presumably through its role in twitching motility.
Resumo:
This paper evaluates and quantifies the environmental impact resulting from the combination of biodiesel fuel (pure or blended with diesel), and diesel combustion in thermoelectric power plants that utilize combined cycle technology (CC). In regions without natural gas, the option was to utilize diesel fuel; the consequence would be a greater emission of pollutants. Biodiesel is a renewable fuel which has been considerably interesting in Brazil power matrix in recent years. The concept of ecological efficiency, largely evaluates the environmental impact caused by CO(2), SO(2), NO(x) and particle matter (PM) emissions. The pollution resulting from biodiesel and diesel combustion is analyzed, separately considering CO(2), SO(2), NO(x) and particulate matter gas emissions, and comparing them international standards currently used regarding air quality. It can be concluded that it is possible to calculate the qualitative environmental factor, and the ecological effect, from a thermoelectric power plant utilizing central heat power (CHP) of combined cycle. The ecological efficiency for pure biodiesel fuel (B100) is 98.16%; for biodiesel blended with conventional diesel fuel, B20 (20% biodiesel and 80% diesel) is 93.19%. Finally, ecological efficiency for conventional diesel is 92.18%, as long as a thermal efficiency of 55% for thermoelectric power plants occurs. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.
Resumo:
In the framework of the micro-CHP (Combined Heat and Power) energy systems and the Distributed Generation (GD) concept, an Integrated Energy System (IES) able to meet the energy and thermal requirements of specific users, using different types of fuel to feed several micro-CHP energy sources, with the integration of electric generators of renewable energy sources (RES), electrical and thermal storage systems and the control system was conceived and built. A 5 kWel Polymer Electrolyte Membrane Fuel Cell (PEMFC) has been studied. Using experimental data obtained from various measurement campaign, the electrical and CHP PEMFC system performance have been determinate. The analysis of the effect of the water management of the anodic exhaust at variable FC loads has been carried out, and the purge process programming logic was optimized, leading also to the determination of the optimal flooding times by varying the AC FC power delivered by the cell. Furthermore, the degradation mechanisms of the PEMFC system, in particular due to the flooding of the anodic side, have been assessed using an algorithm that considers the FC like a black box, and it is able to determine the amount of not-reacted H2 and, therefore, the causes which produce that. Using experimental data that cover a two-year time span, the ageing suffered by the FC system has been tested and analyzed.
Resumo:
The use of biomass-derived liquids (in short: bioliquids) instead of solid biomass can help overcome some of the barriers hindering a wider use of biomass in smaller-scale CHP systems. Relevant bioliquids included biodiesel, vegetable oils as well straight and upgraded pyrolysis oil. In this joint EU-Russian research project Bioliquids-CHP prime movers (engines and turbines) will be developed and modified so that these can run efficiently on bioliquids. At the same time, bioliquids will be upgraded and blended in order to facilitate their use in prime movers. Preliminary results with regard to bioliquid selection, production, and characterisation; the selection and modification of a micro gas turbine; and the development of engines and components are discussed. The research also covers NOx emission reduction and control and an assessment of the benefits and economics of bioliquids-based CHP systems in EU and Russian markets.
Resumo:
This chapter discusses the current state of biomass-based combined heat and power (CHP) production in the UK. It presents an overview of the UK's energy policy and targets which are relevant to the deployment of biomass-based CHP and summarises the current state for renewable, biomass and CHP. A number of small-scale biomass-based CHP projects are described while providing some indicative capital costs for combustion, pyrolysis and gasification technologies. For comparison purposes, it presents an overview of the respective situation in Europe and particularly in Sweden, Finland and Denmark. There is also a brief comment about novel CHP technologies in Austria. Finally it draws some conclusions on the potential of small-scale biomass CHP in the UK. © 2011 Woodhead Publishing Limited All rights reserved.
Resumo:
The present work, where additional value-creating processes in existing combined heat and power (CHP) structures have been examined, is motivated by a political- and consumer-driven strive towards a bioeconomy and a stagnation for the existing business models in large parts of the CHP sector. The research is based on cases where the integration of flash pyrolysis for co-production of bio-oil, co-gasification for production of fuel gas and synthetic biofuels as well as leaching of extractable fuel components in existing CHP plants have been simulated. In particular, this work has focused on the CHP plants that utilize boilers of fluidized bed (FB) type, where the concept of coupling a separate FB reactor to the FB of the boiler forms an important basis for the analyses. In such dual fluidized bed (DFB) technology, heat is transferred from the boiler to the new rector that is operating with other fluidization media than air, thereby enabling other thermochemical processes than combustion to take place. The result of this work shows that broader operations at existing CHP plants have the potential to enable production of significant volumes of chemicals and/or fuels with high efficiency, while maintaining heat supply to external customers. Based on the insight that the technical preconditions for a broader operation are favourable, the motivation and ability among the incumbents in the Swedish CHP sector to participate in a transition of their operation towards a biorefinery was examined. The result of this assessment showed that the incumbents believe that a broader operation can create significant values for their own operations, the society and the environment, but that they lack both a strong motivation as well as important abilities to move into the new technological fields. If the concepts of broader production are widely implemented in the Swedish FB based CHP sector, this can substantially contribute in the transition towards a bioeconomy.