Co-combustion of animal carcasses and slaughterhouse waste products (animal waste), which are classed as high-risk infectious waste, has been considered as a “fuel opportunity” for waste-to-energy boilers. In this study, the impact of co-combustion of animal waste with municipal solid waste (MSW) on operational issues such as bed agglomeration, deposit formation and emission was investigated, employing experimental and theoretical methods. In the experimental section, a series of full-scale tests in a bubbling fluidised-bed boiler were carried out, to determine the effects of animal waste co-combustion on the issues addressed. Two combustion scenarios were considered, identified as the reference (Ref) case and the animal waste (AW) case. In the Ref case, a solid-waste fuel mix, consisting of sorted and pretreated industry and household waste was combusted. In the AW case, 20 wt% AW was added to the reference fuel mix. The collected samples, which included super-heater deposits, fuel mixes and bed and fly ashes, were analysed, using chemical fractionation, SEM-EDX and XRD. In addition, the flue gases´ emission rate were continuously analysed, using FTIR spectrometry. The results showed positive effects from co-combustion of AW, indicating decreased deposit formation and lower risk of bed agglomeration, as well as reduced emissions of NOx and SO2. Moreover, it was found that the concentrations of P, Ca, S and Cl were enriched in the bed materials. In the theoretical section, thermodynamic calculations, with respect to experimental data, were performed to provide greater understanding of the ash transformation behaviour and the related melting temperature. The calculations mainly focused on bed agglomeration, where addition of AW to the MSW considerably reduced the risk of agglomeration. The results of equilibrium products and phase diagram information for the bed ashes suggested melt-induced agglomeration as a possible cause of the formation of sticky layers on the bed particle in the Ref case. Moreover, it was concluded that higher amounts of calcium phosphate and sulfates increased the first melting temperature of the bed ashes in the AW case. / <p><strong>Sponsorship</strong>:</p><p>Waste Refinery and Sparbanksstiftelsen Sjuhärad</p>

No description available.

Lime is a material with a wide range of applications including land improvement, water treatment as well as the paper-, steel-, and cement industry. Annual worldwide production was estimated at 350 Mt/year for 2016 and 2017 and the production is responsible for a large contribution of the greenhouse gas CO2 to the atmosphere, contributing to global warming. Since there is a need for high temperatures in the production process it is common that fossil fuels are used due to their high energy density and favourable combustion characteristics. Therefore a net emission of CO2 comes from the fuel, but a large amount is also released from the calcination of the raw material, limestone, approximately 1 ton of CO2 is released for every ton of quicklime (CaO) produced. Efforts are being made toward reducing emissions from both the fuel and the limestone. Nordkalk AB, for whom this work has been performed, are aiming to partly replace their use of fossil fuel in their lime kiln in Köping with renewable biomass alternatives. The purpose of this study was to establish a mass balance over the lime kiln in Köping for different limestone and fuel mixes and study the effects they had on mass balance for sulphur, potassium, and chlorine. Five different periods were studied where four of them had fuel mixes consisting of fossil fuels (coal and oil) and in the fifth period olive pomace, a renewable fuel, was added to the fuel mix at 11 % of the net calorific input. It was found that no significant change in product quality occurred and no increase in sulphur and chlorine emissions through the flue gas was detected with this fuel addition. However there were indications from throughput calculations that buildup of corrosive deposits, such as KCl, could be occurring with the addition of olive pomace due to comparatively large input of potassium and chlorine. The increased sulphur input form olive pomace appeared to accumulate in the lime kiln dust mass flow while flue gas emissions remained unchanged. This method of establishing a mass balance is considered to be a good way to understand how different inputs affect the elemental balances over a lime kiln. However the quality of the mass balance is highly dependent on how representative the composition of the mass flows are and how they are acquired.

No description available.

BAE Systems Hägglunds AB har sedan 2001 tillhandahållit den midjestyrda bandvagnen BvS10. BvS10 är ett armerat och amfibiskt allterrängsfordon som är utformat för att ge operativt stöd både militärt och civilt där andra fordon inte kan. Kylsystemet i BvS10 har sitt luftintag på taket på fordonets främre del och sitt utblås bakåt ut över styrdonet som kopplar samman bak- och framvagn. I den här rapporten har det utvärderats om ändringar i geometrin av delar i kylsystemet och om den alternativa radialfläkt som identifierats ger ett gynnsammare luftflöde jämfört med den tillförda fläkteffekten. I Catia V5 ritades en förenklad grundmodell av kylsystemet i 3D och de fyra koncept som togs fram upp. De simulerades sedan i programmet FloEFD. Koncepten som togs fram visade inget gynnsammare luftflöde jämfört med den tillförda fläkteffekten. Beräkningar visar att den nya fläkten Airscrew 475MP4 IGV ger ett ökat luftflöde vid samma fläkteffekt. En optimering utfördes och visade en minskning av driveffekten för fläkten med 15,5 kW vid ett luftflöde på 6,15 kg/s. Ett byte till Airscrew 475MP4 IGV är därför rekommenderat. / BAE Systems Hägglunds AB have since 2001 provided the twin-bodied all-terrain vehicle BvS10. BvS10 is an armored and amphibious vehicle that is designed to provide total operational support where other vehicles cannot. The cooling system in BvS10 has its air intake on the roof on the front part of the vehicle and its exhaust backwards out over the connection which interconnects the rear- and front chassis. In this report, it has been evaluated whether if changes in the geometry of parts of the cooling system and if the alternative radial fan identified gives a more favorable air flow compared to the supplied fan power. Catia V5 was used to design a simplified model of the cooling system in 3D and the four concepts that were developed. Then they were simulated in FloEFD. The concepts that were developed did not show a more favorable airflow compared to the supplied fan effect. Calculations show that the new fan Airscrew 475MP4 IGV provided an increased air flow at the same fan power. An optimization was performed and showed a reduction in the drive power of the fan with 15,5 kW at an air flow of 6,15 kg/s. A change to Airscrew 475MP4 IGV is therefore recommended.

Den här rapporten undersöker effekten av en spränggenerator (Eng: shock pulse generator) som är installerad vid överhettarna på Umeå energis avfallseldade kraftvärmeanläggning Dåva 1, lokaliserad ca 9 km nordost om Umeå. Utredningen behandlar ämnet dels utifrån tekniska aspekter, vad gäller drifterfarenheter och prestanda samt ekonomiska aspekter, vad gäller återbetalningstiden och driftkostnader. Vidare diskuteras förbättringsförslag för spränggeneratorn samt en kombination med tillsats av ammoniumsulfat för att förebygga beläggningsbildning och korrosion på överhettarna. Med programmet (ABB 800xa Smart Client) har driftdata samlats in för att studera temperaturprofiler och trender över temperaturerna på överhettarna. Med dessa värden har sedan beräkningar utförts för att få fram ett värmegenomgångstal (UA-värde). UA-värdet beskriver dels hur bra värmeöverföringen är och ger en indikation på graden av beläggningsbildningen. Detta har undersökts från perioder före och efter spränggeneratorns installation. Genom intervjuer med drift- och underhållspersonal har underlag kring kostnader kopplat till spränggeneratorn tagits fram till att göra en ekonomisk kalkyl.   Resultaten visar på att spränggeneratorn haft ett positivt resultat med en ökning av medelvärdet för UA på 7%. Med en lägre tillväxt av beläggningar med spränggeneratorn finns det också möjligheter för att minska på drift- och underhållskostnader. En förbättring av spränggeneratorns funktion hade också kunnat uppnås genom att öka sprängningsfrekvensen vid perioder där igensättningar brukar uppstå. En metod i framtiden kan vara att kombinera UA-värdet med spränggeneratorn för en behovsstyrd sotning.   Återbetalningstiden för den installerade spränggeneratorn bedöms till 5.7 år med en besparing på 385 000 kr/år. Vad gäller eventuell installation av ännu en spränggenerator, så tyder denna utvärdering att det inte bedöms vara lika lönsamt som med enbart en spränggenerator. Det har även genomförts en mindre litteraturstudie som behandlar beläggningsbildning på överhettartuber och möjligheter att motverka detta med tillsats av ammoniumsulfat. Enligt tidigare studier bildar man avlagringar med högre halt av svavel än klor vilket får avlagringar att bli mindre korrosiva, porösare som därmed avlägsnas enklare. Detta kan vara intressant för Dåva 1 och kan vara ett förslag till vidare utredning. / The aim of this report was to evaluate a shock pulse generator installed at Dåva 1, the waste-fired combined heat and power (CHP) plant at Umeå Energi AB, located about 9 km northeast of Umeå. The study deals with the subject based on both technical aspects, in terms of operating experience and performance. Financial aspects, regarding repayment time and operating costs. With these results, an investment for a shock pulse generator has been discussed. Furthermore, proposals for improvements or combinations with ammonium sulphate should be discussed in order to prevent corrosion, in particular chlorine-induced corrosion. With the data logging program (ABB 800xa Smart Client), it was possible to study temperature trends and profiles at the superheaters. With these data, calculations have been performed to obtain a heat transfer coefficient (UA-value). The UA-value describes how the heat transfer changes over time and is therefore a measure of the degree of coating formation, and how the shock pulse generator influences this. Comparisons have been made for periods before and after the installation of the shock pulse generator. The study has included several interviews with the operation and maintenance staff concerning costs and experiences, to perform an economic calculation.   The results show that the shock pulse generator have had a positive effect with an increase in the UA mean value by 7%. With reduced growth of deposits with the shock pulse generator, there are possibilities to reduce operating and maintenance costs. An improvement in the efficiency of the shock pulse generator could also have been achieved by increasing the frequency of explosion during periods where coating formation occurs. A future method could be to combine the UA-value with the shock pulse generator to create an intelligent soot-blowing system.   The payback period for the installed shock pulse generator is estimated to be 5.7 years with a saving of SEK 385,000/year. For the assessment of an extra shock pulse generator, the evaluation indicate that it would probably not be as profitable as the present shock pulse generator. A minor literature study was also performed concerning deposit formation on superheater tubes and the effects of addition of ammonium sulphate. According to previous studies, deposits with a higher content of sulfur than chlorine are formed when using such additive, which causes deposits to become less corrosive and more porous, which makes them easier to be removed. This can be interesting for Dåva 1 and can be a suggestion for further investigation.

Volvo Trucks in Umeå use large amounts of compressed air and the air compressors at Volvo use large amounts of energy every year. The majority of the energy supplied to the compressors goes to heat losses cooled to the Ume River and groundwater. The purpose of this project was to develop a new heat recovery system where a larger part of the compressor heat is used and various suggestions for optimizations on the compressed air system. Lack of digital control systems on the compressed air system has led to various operating problems and difficulties in diagnosing them while making optimizations difficult. The absence of logged data led to lack of various critical compressor data that instead had to be estimated with different calculation methods. The report resulted in a number of measures that were proposed, such as an investment in a variable speed drive compressor with heat recovery to the district heating system, various operating optimizations and a reworking of the current heat recovery system. The heat recovery systems showed to have great saving potential with a short payback period. The heat recovery systems that were developed in the project was to recycle heat from a new air compressor to the return line on the district heating at a station inside the factory and a heat exchange on three current compressors towards a nearby district heating line. It was thus possible to show significant reductions in the amount of purchased district heating and energy costs without affecting other processes. An outdated compressed air system showed higher future costs due to increased service costs and a future need for renovations on compressors. This means that Volvo probably would have reduced costs by investing in a new air compressor.

No description available.

No description available.

This thesis investigates the performance of varied control systems in a office building in the southern parts of Sweden. The control system is designed according to standard EN15232 with three levels of building automation and control systems with a multi-zone approach. Highest standard, class A, is a demand control system with VAV controlled by temperature and CO2-levels in each zone. The lighting in class A is controlled by user demand and dimmers with regard to daylight to meet lighting regulations. The ventilation in the middle system, class B, is VAV controlled by temperature and demand in a zone. lighting is only on when a zone is used but no opportunity to dimmer. The reference object, class C, uses constant air volume CAV based on Swedish regulation and has lighting as in class B. The building envelope is varied between an existing model with 70Às building standard, according to todayÀs standard, and passive house standard in Sweden. All simulations is evaluated through energy performance and indoor climate in terms of temperature, PMV, PPD and CO2-levels. Simulations showed that the class A system has the highest possibility to decrease the energy use compared to the other systems. The reduction in total energy use differs from about 9-27% compared to class C and about 29-34% in electric energy use. Simulations also showed that class A and B are more advantageous to apply in a passive house rather than in the existing building if the total energy is evaluated. With regards to electric energy use, the difference between the building envelopes is too small to state that any difference exists. Neither one of the systems corresponds to ”good” indoor climate in the critical zones, all three is between the range ”good” and ”acceptable” according to standard SE-EN15251. Class A and B show an overall improvement of PMV and PPD compared to class C system. The class B system is closest to fulfill a ”good” indoor climate, especially in the passive house model. Evaluation with respect to CO2-levels class A and C showed acceptable levels.