931 resultados para mikro CHP
Resumo:
De-inking sludge is a waste product generated from secondary fibre paper mills who manufacture recycled paper into new paper sheets; it refers directly to the solid residues which evolve during the de-inking stage of the paper pulping process. The current practice for the disposal of this waste is either by land-spreading, land-filling or incineration which are unsustainable. This work has explored the intermediate pyrolysis of pre-conditioned de-inking sludge pellets in a recently patented 20 kg/h intermediate pyrolysis reactor (The Pyroformer). The reactor is essentially two co-axial screws which are configured in such a way as to circulate solids within the reactor and thus facilitate in the cracking of tars. The potential application of using the volatile organic vapours and permanent gases evolved would be to generate both combined heat and power (CHP) located at paper making sites. The results show that de-inking sludge could be successfully pyrolysed and the organic vapours produced were composed of a mixture of aromatic hydrocarbons, phenolic compounds and some fatty acid methyl esters as detected by liquid GC-MS. The calorific value of the oil after condensing was between 36 and 37 MJ/kg and the liquid fuel properties were also determined, permanent gases were detected by a GC-TCD and were composed of approximately 24% CO, 6% CH and 70% CO (v/v%). The solid residue from pyrolysis also contained a small residual calorific value, and was largely composed of mainly calcium based inert metal oxides. The application of applying intermediate pyrolysis to de-inking sludge for both CHP production and waste reduction is in principle a feasible technology which could be applied at secondary fibre paper mills. © 2013 Elsevier B.V. All rights reserved.
Resumo:
Brewers spent grain (BSG) is a widely available feedstock representing approximately 85% of the total by-products generated in the brewing industry. This is currently either disposed of to landfill or used as cattle feed due to its high protein content. BSG has received little or no attention as a potential energy resource, but increasing disposal costs and environmental constraints are now prompting the consideration of this. One possibility for the utilisation of BSG for energy is via intermediate pyrolysis to produce gases, vapours and chars. Intermediate pyrolysis is characterised by indirect heating in the absence of oxygen for short solids residence times of a few minutes, at temperatures of 350-450 °C. In the present work BSG has been characterised by chemical, proximate, ultimate and thermo-gravimetric analysis. Intermediate pyrolysis of BSG at 450 °C was carried out using a twin coaxial screw reactor known as Pyroformer to give yields of char 29%, 51% of bio-oil and 19% of permanent gases. The bio-oil liquid was found to separate in to an aqueous phase and organic phase. The organic phase contained viscous compounds that could age over time leading to solid tars that can present problems in CHP application. The quality of the pyrolysis vapour products before quenching can be upgraded to achieve much improved suitability as a fuel by downstream catalytic reforming. A Bench Scale batch pyrolysis reactor has then been used to pyrolyse small samples of BSG under a range of conditions of heating rate and temperature simulating the Pyroformer. A small catalytic reformer has been added downstream of the reactor in which the pyrolysis vapours can be further cracked and reformed. A commercial reforming nickel catalyst was used at 500, 750 and 850 °C at a space velocity about 10,000 L/h with and without the addition of steam. Results are presented for the properties of BSG, and the products of the pyrolysis process both with and without catalytic post-processing. Results indicate that catalytic reforming produced a significant increase in permanent gases mainly (H2 and CO) with H2 content exceeding 50 vol% at higher reforming temperatures. Bio-oil yield decreased significantly as reforming temperature increased with char remaining the same as pyrolysis condition remained unchanged. The process shows an increase in heating value for the product gas ranging between 10.8-25.2 MJ/m as reforming temperature increased. © 2012 Elsevier B.V. All rights reserved.
Resumo:
Secondary fibre paper mills are significant users of both heat and electricity which is mainly derived from the combustion of fossil fuels. The cost of producing this energy is increasing year upon year. These mills are also significant producers of fibrous sludge and reject waste material which can contain high amounts of useful energy. Currently the majority of these waste fractions are disposed of by landfill, land-spread or incineration using natural gas. These disposal methods not only present environmental problems but are also very costly. The focus of this work was to utilise the waste fractions produced at secondary fibre paper mills for the on-site production of combined heat and power (CHP) using advanced thermal conversion methods (gasification and pyrolysis), well suited to relatively small scales of throughput. The heat and power can either be used on-site or exported. The first stage of the work was the development of methods to condition selected paper industry wastes to enable thermal conversion. This stage required detailed characterisation of the waste streams in terms of proximate and ultimate analysis and heat content. Suitable methods to dry and condition the wastes in preparation for thermal conversion were also explored. Through trials at pilot scale with both fixed bed downdraft gasification and intermediate pyrolysis systems, the energy recovered from selected wastes and waste blends in the form of product gas and pyrolysis products was quantified. The optimal process routes were selected based on the experimental results, and implementation studies were carried out at the selected candidate mills. The studies consider the pre-processing of the wastes, thermal conversion, and full integration of the energy products. The final stage of work was an economic analysis to quantify economic gain, return on investment and environmental benefits from the proposed processes.
Resumo:
The two main wastes generated from secondary fibre paper mills are rejects (composed mainly of plastics and fibres) and de-inking sludge, both of which are evolved from the pulping process during paper manufacture. The current practice for the disposal of these wastes is either by land-spreading or land-filling. This work explores the gasification of blends of pre-conditioned rejects and de-inking sludge pellets with mixed wood chips in an Imbert type fixed bed downdraft gasifier with a maximum feeding capacity of 10kg/h. The producer gases evolved would generate combined heat and power (CHP) in an internal combustion engine. The results show that as much as 80wt.% of a brown paper mill's rejects (consisting of 20wt.% mixed plastics and 80wt.% paper fibres) could be successfully gasified in a blend with 20wt.% mixed wood chips. The producer gas composition was 16.24% H, 23.34% CO, 12.71% CO 5.21% CH and 42.49% N (v/v%) with a higher heating value of 7.3MJ/Nm. After the removal of tar and water condensate the producer gas was of sufficient calorific value and flow rate to power a 10kWe gas engine. Some blends using rejects from other mill types were not successful, and the limiting factor was usually the agglomeration of plastics present within the fuel.
Resumo:
The use of the pyrolysis process to obtain valuable products from biomass is amongst the technologies being investigated as a source for renewable energy. The pyrolysis process yields products such as biochar, bio-oil and non condensable gases. The main objective of this project is to increase energy recovery from sewage sludge by utilising the intermediate pyrolysis process. The intermediate pyrolysis has a residence time ranging from 5 to 10 minutes. The main product yields from sewage sludge pyrolysis are 50 wt% biochar, 40 wt% bio-oil and 10 wt% non condensable gases. The project was carried out on a pilot plant scale reactor with a load capacity of 20 kg/h. This enabled a high yield of biochar and bio-oil. The characterisation of the products indicated that the organic phase of the bio-oil had good fuel properties such as having high energy content of 39 MJ/kg, low acid number of 21.5, high flash point of 150 and viscosity of 35 cSt. An increase in pyrolysis experiments enabled large quantities of pyrolysis oil production. Co-pyrolysis of sewage sludge was carried out on laboratory scale with mixed wood, rapeseed and straw. It found that there was an increase in bio-oil quantity with rapeseed while co-pyrolysis with wood helped to mask the smell of the sludge pyrolysis oil. Engine test were successfully carried out in an old Lister engine with pyrolysis oil fractions of 30% and 50% blended with biodiesel. This indicates that these pyrolysis oil fractions can be used in similar engine types without any problems however long term effects in ordinary engines are unknown. An economic evaluation was carried out about the implementation of the intermediate pyrolysis process for electricity production in a CHP using the pyrolysis oil. The prices of electricity per kWh were found to be very high.
Resumo:
Biomass is projected to account for approximately half of the new energy production required to achieve the 2020 primary energy target in the UK. Combined heat and power (CHP) bioenergy systems are not only a highly efficient method of energy conversion, at smaller-scales a significant proportion of the heat produced can be effectively utilised for hot water, space heating or industrial heating purposes. However, there are many barriers to project development and this has greatly inhibited deployment in the UK. Project viability is highly subjective to changes in policy, regulation, the finance market and the low cost incumbent; a high carbon centralised energy system. Unidentified or unmitigated barriers occurring during the project lifecycle may not only negatively impact on the project but could ultimately lead to project failure. The research develops a decision support system (DSS) for small-scale (500 kWe to 10 MWe) biomass combustion CHP project development and risk management in the early stages of a potential project’s lifecycle. By supporting developers in the early stages of project development with financial, scheduling and risk management analysis, the research aims to reduce the barriers identified and streamline decision-making. A fuzzy methodology is also applied throughout the developed DSS to support developers in handling the uncertain or approximate information often held at the early stages of the project lifecycle. The DSS is applied to a case study of a recently failed (2011) small-scale biomass CHP project to demonstrate its applicability and benefits. The application highlights that the proposed development within the case study was not viable. Moreover, further analysis of the possible barriers with the DSS confirmed that some possible modifications to be project could have improved this, such as a possible change of feedstock to a waste or residue, addressing the unnecessary land lease cost or by increasing heat utilisation onsite. This analysis is further supported by a practitioner evaluation survey that confirms the research contribution and objectives are achieved.
Resumo:
This thesis presents a techno-economic investigation of the generation of electricity from marine macroalgae (seaweed) in the UK (Part 1), and the production of anhydrous ammonia from synthesis gas (syngas) generated from biomass gasification (Part 2). In Part 1, the study covers the costs from macroalgae production to the generation of electricity via a CHP system. Seven scenarios, which varied the scale and production technique, were investigated to determine the most suitable scale of operation for the UK. Anaerobic digestion was established as the most suitable technology for macroalgae conversion to CHP, based on a number of criteria. All performance and cost data have been taken from published literature. None of the scenarios assessed would be economically viable under present conditions, although the use of large-scale electricity generation has more potential than small-scale localised production. Part 2 covers the costs from the delivery of the wood chip feedstock to the production of ammonia. Four cases, which varied the gasification process used and the scale of production, were investigated to determine the most suitable scale of operation for the UK. Two gasification processes were considered, these were O2-enriched air entrained flow gasification and Fast Internal Circulating Fluidised Bed. All performance and cost data have been taken from published literature, unless otherwise stated. Large-scale (1,200 tpd) ammonia production using O2-enriched air entrained flow gasification was determined as the most suitable system, producing the lowest ammonia-selling price, which was competitive to fossil fuels. Large-scale (1,200 tpd) combined natural gas/biomass syngas ammonia production also generated ammonia at a price competitive to fossil fuels.
Resumo:
De-inking sludge is a waste product generated from secondary fibre paper mills who manufacture recycled paper into new paper sheets; it refers directly to the solid residues which evolve during the de-inking stage of the paper pulping process. The current practice for the disposal of this waste is either by land-spreading, land-filling or incineration which are unsustainable. This work has explored the intermediate pyrolysis of pre-conditioned de-inking sludge pellets in a recently patented 20 kg/h intermediate pyrolysis reactor (The Pyroformer). The reactor is essentially two co-axial screws which are configured in such a way as to circulate solids within the reactor and thus facilitate in the cracking of tars. The potential application of using the volatile organic vapours and permanent gases evolved would be to generate both combined heat and power (CHP) located at paper making sites. The results show that de-inking sludge could be successfully pyrolysed and the organic vapours produced were composed of a mixture of aromatic hydrocarbons, phenolic compounds and some fatty acid methyl esters as detected by liquid GC-MS. The calorific value of the oil after condensing was between 36 and 37 MJ/kg and the liquid fuel properties were also determined, permanent gases were detected by a GC-TCD and were composed of approximately 24% CO, 6% CH and 70% CO (v/v%). The solid residue from pyrolysis also contained a small residual calorific value, and was largely composed of mainly calcium based inert metal oxides. The application of applying intermediate pyrolysis to de-inking sludge for both CHP production and waste reduction is in principle a feasible technology which could be applied at secondary fibre paper mills. © 2013 Elsevier B.V. All rights reserved.
Resumo:
This study investigates the use of Pyroformer intermediate pyrolysis system to produce alternative diesel engines fuels (pyrolysis oil) from various biomass and waste feedstocks and the application of these pyrolysis oils in a diesel engine generating system for Combined Heat and Power (CHP) production. The pyrolysis oils were produced in a pilot-scale (20 kg/h) intermediate pyrolysis system. Comprehensive characterisations, with a view to use as engine fuels, were carried out on the sewage sludge and de-inking sludge derived pyrolysis oils. They were both found to be able to provide sufficient heat for fuelling a diesel engine. The pyrolysis oils also presented poor combustibility and high carbon deposition, but these problems could be mitigated by means of blending the pyrolysis oils with biodiesel (derived from waste cooking oil). The blends of SSPO (sewage sludge pyrolysis oil) and biodiesel (30/70 and 50/50 in volumetric ratios) were tested in a 15 kWe Lister type stationary generating system for up to 10 hours. There was no apparent deterioration observed in engine operation. With 30% SSPO blended into biodiesel, the engine presents better overall performance (electric efficiency), fuel consumption, and overall exhaust emissions than with 50% SSPO blend. An overall system analysis was carried out on a proposed integrated Pyroformer-CHP system. Combined with real experimental results, this was used for evaluating the costs for producing heat and power and char from wood pellets and sewage sludge. It is concluded that the overall system efficiencies for both types of plant can be over 40%; however the integrated CHP system is not economically viable. This is due to extraordinary project capital investment required.
Resumo:
The brewing process is an energy intensive process that uses large quantities of heat and electricity. To produce this energy requires a high, mainly fossil fuel consumption and the cost of this is increasing each year due to rising fuel costs. One of the main by-products from the brewing process is Brewers Spent Grain (BSG), an organic residue with very high moisture content. It is widely available each year and is often given away as cattle feed or disposed of to landfill as waste. Currently these methods of disposal are also costly to the brewing process. The focus of this work was to investigate the energy potential of BSG via pyrolysis, gasification and catalytic steam reforming, in order to produce a tar-free useable fuel gas that can be combusted in a CHP plant to develop heat and electricity. The heat and electricity can either be used on site or exported. The first stage of this work was the drying and pre-treatment of BSG followed by characterisation to determine its basic composition and structure so it can be evaluated for its usefulness as a fuel. A thorough analysis of the characterisation results helps to better understand the thermal behaviour of BSG feedstock so it can be evaluated as a fuel when subjected to thermal conversion processes either by pyrolysis or gasification. The second stage was thermochemical conversion of the feedstock. Gasification of BSG was explored in a fixed bed downdraft gasifier unit. The study investigated whether BSG can be successfully converted by fixed bed downdraft gasification operation and whether it can produce a product gas that can potentially run an engine for heat and power. In addition the pyrolysis of BSG was explored using a novel “Pyroformer” intermediate pyrolysis reactor to investigate the behaviour of BSG under these processing conditions. The physicochemical properties and compositions of the pyrolysis fractions obtained (bio-oil, char and permanent gases) were investigated for their applicability in a combined heat power (CHP) application.
Resumo:
Today, focus is shifting to creation of bio-energy, biofuel and bioproducts from cellulosic biomass derived from various sources, including existing and new crops and their residues, trees and forest residues, and municipal or industrial wastes. At present, biomass co-firing in modern coal power plants with efficiencies up to 45% is the most cost-effective biomass use for power generation. Due to feedstock availability issues, dedicated biomass plants for combined heat and power (CHP), are typically of smaller size and lower electrical efficiency compared to coal plants. The financial model discussed in the chapter is suitable for all countries both in the West and in the developing world. From the economic analysis given in the chapter it can be concluded that intermediate pyrolysis technology proves to be very effective in terms of product qualities of the oil produced and also the return on investment is around 4 to 5 years.
Resumo:
2004-ben Magyarország kilenc közép-kelet európai országgal együtt csatlakozott az Európai Unióhoz, amely számos változást idézett elő az agrárkereskedelem terén. A téma fontosságának ellenére az EU csatlakozás agrárkereskedelmi hatásainak vizsgálatával az új tagországokban eddig viszonylag kevés munka foglalkozott. A cikk célja ezért a téma hiányos szakirodalmának bővítése egy specializációs elemzés elkészítésével, amely a csatlakozás hazai mezőgazdasági alapanyagok és feldolgozott termékek kereskedelmére gyakorolt hatását vizsgálja. A cél elérése érdekében a cikk először ismerteti a kutatás empirikus hátterét, valamint az alkalmazott módszertant, nevezetesen a megnyilvánuló komparatív előnyök elméletén alapuló különböző módszereket. A második részben a számítások eredményeit elemezzük, amelynek elvégzéséhez a cikk az Eurostat adatbázisát használja HS6-os rendszerben az adatok forrásaként, 1999-2010 évekre. A munka harmadik része az adatok mögé tekint és agrárpolitikai következtetéseket és javaslatokat fogalmaz meg, kombinálva a mikro- és makro-szintű elemzést. A hazai agrárkereskedelem specializációjának vizsgálatát a megnyilvánuló komparatív előnyök módszerével elvégezve bebizonyosodott, hogy csak a mezőgazdasági alapanyagok egy része rendelkezett megnyilvánuló komparatív előnnyel 1999-2010 között, míg a mezőgazdasági feldolgozott termékek egyértelműen komparatív hátrányban voltak, noha a csatlakozás előbbiek gyengülését, míg utóbbiak erősödését hozta. Agrárpolitikai szempontból az eredmények relevanciája vitathatatlan, hiszen a bemutatott változások alapvetően a magyar mezőgazdaság és élelmiszeripar régóta meglévő belső problémáinak és a megváltozott piaci feltételeknek az együttes eredői. Ezek közül kiemelendő a megváltozott piaci körülményekhez történő hatékony alkalmazkodás képességének hiánya, a hazai mezőgazdaság rossz termelési struktúrája, az új piaci körülmények és a kedvezőtlen világpiaci folyamatok következményei és a hazai feldolgozóipar rendszerváltás óta meglévő problémái. A jövőben világosan kell látni, hogy a magyar mezőgazdaság, élelmiszeripar és az élelmiszer-kereskedelem nem fejlődhet egymás kárára, ehhez azonban hosszú távú, strukturális változásokra van szükség a magyar mezőgazdaságban és élelmiszeriparban is.
Resumo:
A szerző cikkében megpróbál rávilágítani annak fontosságára, hogy az Európai Unióból érkező fejlesztési támogatások hasznosulása és a támogatási rendszer hatékonysága között jelentős különbség van. Ha nem tudjuk hatékonyan és hatásosan felhasználni az Unióból érkező pénzügyi eszközöket, akkor a cél: a kohézió, a konvergencia az Európai Unió régi tagállamainak fejlettségi szintjéhez, jólétéhez még nehezebben és lassabban érhető el. Az uniós támogatások hatékonysága alapvetően a rendelkezésre álló pénz lekötésének, lehívásának arányából, illetve a lekötött, lehívott és esetleg visszafizetett összeg arányából állapítható meg (kvantitatív megközelítés). A támogatások felhasználásának hatékonyságánál bonyolultabb, jóval összetettebb megközelítést igényel a hatásosság fogalma. A felhasználás hatásosságát a projektszinten a támogatás hatására megtermelt hozzáadott értékkel, programszinten a GDP hozzáadott növekedéssel lehet kifejezni. A cikk alapvetően a ROP 1.2 "Turisztikai fogadóképesség javítása" pályázati kiírás nyertes projektjeinél végzett kutatás eredményein keresztül kívánja szemléltetni a projektszintű vagy mikro hatásosság fontosságára (kvalitatív megközelítés). _________ The author tries to highlight the importance the difference between the efficiency and effectiveness of using the EU-subsidies. If Hungary cannot use the financial means of the EU efficiently and effectively, than the goal: cohesion and convergence to the level of the old, developed countries of the EU will be much harder and slowly. The efficiency of the EU-subsidies can be measured by the ratio of the amount of money obliged and the amount of money spent, and by the amount of money withdrawn by the Commission, which is actually lost (quantitative approach). The effectiveness of EU-subsidies needs a much more complicated and complex approach, than the efficiency. The effectiveness of usage on project level can be measured by the "added value" of the project, on program level by the added GDP growth or employment. The article is analysing basically the results of a survey made among the winner project of the application ROP 1.2 (Regional Operational Program 1.2) Improving the capacity for tourism (project level or micro effectiveness – qualitative approach).
Resumo:
Tanulmányunk a gazdasági versenyképességgel, kiemelten annak nemzetgazdasági szintű vetületével és a sport esetében történő értelmezésével foglakozik. A gazdasági versenyképesség esetén kiemelten kezeljük az IMD és a WEF versenyképességi rangsorait, a sport esetén pedig szétválasztjuk a hivatásos és a szabadidősportot. A hivatásos sport esetén bemutatjuk a sportszakmai versenyképességet indikáló és a sportszakmai versenyképességre hatással lévő gazdasági és társadalmi mutatókat egyaránt. Összehasonlítási csoportot képeztünk, amelyben Magyarország és a környező országok szerepelnek és a komparatív elemzés kiterjed a gazdasági és a sportszakmai versenyképességre, valamint a sportszakmai versenyképességre ható gazdasági és társadalmi tényezőkre egyaránt. A sportszakmai versenyképességet az olimpiai érmek számával és azok pontértékével mérjük, amit az olimpiák teljes történelmére és az elmúlt 20 év különböző szakaszaira egyaránt vizsgálunk, míg a gazdasági és társadalmi tényezőket csak a mondanivalónk szempontjából legrelevánsabb évekre, az új évezredre vizsgálunk. A hivatásos sporttal kapcsolatos versenyképességi kérdésekből azt a következtetést vontuk le, hogy Magyarország történelmi sportszakmai eredményességének fenntartását a jelen gazdasági és társadalmi tényezők nem igazolják, sőt az elmúlt időszak visszaesését támasztják alá és a Londoni olimpián való szereplésünkkel kapcsolatban inkább az összehasonlítási csoporton belüli további visszacsúszást, mintsem az eredmény javulását támogatják. A tanulmányban azt állítjuk, hogy egyéni, vállalati és makrogazdasági versenyképességet is javíthat a szabadidősport. Mikro szinten, majd makrogazdasági szinten elemeztük a szabadidősport hatásait, valamint próbáltunk választ keresni arra a kérdésre, hogy hogyan válhat az egyén, a vállalat és végső célként a gazdaság versenyképesebbé a fizikai aktivitás által. A kevesebb betegség és egészségügyi kiadás, vagy éppen a kedvezőbb várható élettartami mutatók mellett termelékenység-növekedés, a versenyképességi rangsorokban pedig előkelőbb helyezések érhetők el. ______ Our paper tackles the concept of competitiveness in the national level and interprets it also in the field of sport as well. In the economics field we focus on the competitiveness rankings of IMD and WEF and in the sport field we differentiate between professional and leisure sport. In the case of professional sport we introduce the measures of sport competitiveness and its influencing economic and social factors as well. We have made a peer group which contains Hungary and its neighboring countries and the comparative study tackles the sport competitiveness and the influencing economic and social factors as well. We measure sport competitiveness with the Olympic medal count and the medals point value, which is counted in the whole Olympic history, and different phases of the last 20 years. The economic and social factors are compared only in the new millennia as this is the most relevant time frame of this study. From the competitiveness analysis of professional sport we concluded that the maintenance of Hungary’s historical sport successes is not proved by nowadays economic and social factors, however they support the past years decline. These factors also indicate that in London (2012)we would rather slip one more position back in the peer group, than rise again from our ashes. In our opinion leisure sport could enhance the competitiveness of individuals, companies, and economy also. We analysed the effects of leisure sport on the microeconomic and macroeconomic level, and tried to find answer to that question how could be individuals, companies, and economy more competitive through leisure sport. Besides less illness and health care expenditures, longer life expectancy, productivity growth, countries could be well placed in competitiveness’ rankings.
Resumo:
Az innovatív, induló vállalkozások kiemelt jelentőségűek a gazdasági növekedés szempontjából, de jelentős finanszírozási nehézségekkel küzdenek. A kockázati tőkések tekinthetők a fiatal, magas kockázatú vállalatok finanszírozóinak, a kockázatitőkebefektetések kínálata azonban visszaesett a 2008-as gazdasági válság hatására. Magyarországon a kockázati tőkekínálat visszaesése és a mikro-, kis- és középvállalatok rendelkezésére álló, szűkös hitelforrások olyan helyzetet teremtettek, ahol az állami szerepvállalás kerülhetett előtérbe. Tanulmányunkban áttekintjük az induló, innovatív vállalkozások finanszírozási sajátosságait, valamint a kockázatitőke-befektetések főbb jellemzőit és aktuális európai trendjeit. Ezek után az állami beavatkozással foglalkozunk: mivel indokolható az állami szerepvállalás, és az állam milyen eszközökkel segítheti az innovációk megvalósítását? Végül ennek egy megvalósulását, a Magyarországon is elindult Jeremie-programot mutatjuk be, és az eddigi kihelyezések befektetési portfólióját elemezzük a hazai gyakorlat alapján.