FBC: Laboratory Scale Research to Small Scale Practical Operation

2005 ◽  
Author(s):  
E. M. Bulewicz ◽  
S. Kandefer ◽  
M. Pilawska ◽  
W. Z˙ukowski ◽  
J. Baron
Keyword(s):  
Coal Combustion ◽  
Laboratory Scale ◽  
Small Scale ◽  
Laboratory System ◽  
Fluidised Bed ◽  
Physicochemical Processes ◽  
Bubbling Bed ◽  
Practical Operation ◽  
Visual Phenomena ◽  
Combustible Gases

Working with a small, bubbling laboratory scale fluidised bed combustor for many years, helped to gain some insights into the fundamental physicochemical processes taking place in fluidised bed combustors in general, irrespective of size. For example, it has been demonstrated that during coal combustion as a rule the gases leaving the bed cannot be assumed to be at full thermal equilibrium and that when gases are burned the associated acoustic and visual phenomena can be explained in terms of bubbles of the combustible gases exploding within the bed. Much of the experience gained in running the laboratory system has been used in small scale practice, in designing and controlling small, but successful fluidised bed combustors up to about 3 MW. Several 1MW units have now been in operation for over 10 years. It has also been demonstrated that small bubbling bed combustors can be used for disposing of certain biomass and other wastes.

scholarly journals Investigations on disposal of low-calorific landfill gases by a small scale fluidised bubbling bed combustion plant

2013 ◽  
Vol 9 (1) ◽  
pp. 42-50
Keyword(s):  
Gas Flow ◽  
Landfill Gas ◽  
Pollutant Emission ◽  
Small Scale ◽  
Fluidised Bed ◽  
Load Range ◽  
Combustion Gas ◽  
Operation Conditions ◽  
Bubbling Bed ◽  
Landfill Gases

Poor landfill gases cannot be used to drive gas engines or be burnt in gas flares. This follows why the combustion flame front velocity for poor gases becomes very low. From this moment the non-flammable poor landfill gases are polluting the environment. An energetical utilisation of very poor landfill gases is of ecological interest and is also an important contribution for climate protection. A feasible solution must be found. In our University lab we are using a Fluidised Bubbling Bed Combustion (SFBC) plant with 200 kW completed by heat exchangers for pre-heating the combustion air as well the combustion gas. In the past this SFBC-principle had successfully been applied to a thermal utilization of very different wastes. Using this principle we are able to recover the energy content of very poor landfill gases down to a concentration below the lower explosion limit. The fluidised red hot inertia bed material at a temperature of 850°C is an excellent ignition source to run the process at constant parameters within legal limits. Therefore we have very low pollutant emission levels. Using a developed mathematical SFBC-model we theoretically investigated the lowest possibly methane concentration limits under given pre-conditions as well as fluidised bed temperature level, fluidisation air and fuel gas temperatures, necessary oxygen concentration level. Following to these model investigations we realized their experi-mental verification in our 200 kW lab SFBC testing plant in a wide-spread plant load range. These lab tests had very successful results. The possible SFBC operation conditions have been estimated. Based on these results we engineered by the help of industrial partners a real SFBC plant installed on a closed landfill in Mecklenburg – Western Pomerania, 65 km far from our University lab. Using these plant we dispose there real very poor landfill gas. The landfill gas is poor enough to avoid a further operation of a common gas flare. The automatically operated SFBC process is running at 850 °C without any technical interruptions since one year. At the moment the maintenance rate is 3 weeks. The plant is supervised by data remote control. The contribution will compare the lab test results with the results of the real existing plant. If the poor landfill gas flow is strong enough the SFBC produces enough energy e.g. to drive a steam cycle or a gas turbine externally fired by the SFBC that generates electrical power. In this case the necessary power equipment has to be added to the SFBC plant.

scholarly journals First results of pipe pile static load test in small laboratory scale

2018 ◽  
Vol 251 ◽  
pp. 04038 ◽  
Author(s):  
Michal Baca ◽  
Jaroslaw Rybak
Keyword(s):  
Static Load ◽  
Axial Loading ◽  
Laboratory Scale ◽  
Load Test ◽  
Scale Model ◽  
Small Scale ◽  
Small Laboratory ◽  
Static Load Test ◽  
First Results ◽  
Load Tests

Presented laboratory testing program of tubular steel piles is a part of a bigger research program which contained static load tests in full scale and numerical simulations of conducted research. The main goal of the research is to compare static load tests with different working conditions of a shaft. The presented small scale model tests are the last part of the research. The paper contains the testing methodology description and first results of model pile axial loading. The static load tests in a small laboratory scale were conducted in a container filled with uniformly compacted medium sand (MSa). The first results of the investigation are presented in this paper, with the comparison of two pile capacities obtained for different roughness of the pile shaft (skin friction). The results are presented as load-displacement curves obtained by means of the Brinch-Hansen 80% method.

The Fracture and Aerosol Release of Impacted HLW Glasses and HLW Canisters

1988 ◽  
Vol 127 ◽  
Author(s):  
Hans G. Scheibel ◽  
V. Friehmelt ◽  
H. Froehlich
Keyword(s):  
Impact Velocity ◽  
Thermal Stresses ◽  
Full Scale ◽  
Laboratory Scale ◽  
Small Scale ◽  
Release Mechanism ◽  
Experimental Conditions ◽  
Drop Tests ◽  
Ground Plate ◽  
The Impact

ABSTRACTThe fracture and release mechanism of radioactive aerosols of HLW glass and HLW canisters are studied experimentally by laboratory scale and full scale drop tests. The experimental conditions model the conditions of accidental drops in a deep salt repository. The laboratory scale drop tests have a scaling factor of 1:10. Accelerated probes of simulated HLW glass impact on a ground plate and the size distributions of broken fines and released aerosols are measured by sieving and scanning electron microscopy (SEM) of aerosol samples.The impact velocity is determined as the dominating impact parameter. Further parameters tested, such as waste glass composition, cooling time (residual thermal stresses), probe temperature at impact, and ground characteristics, show no measurable influence. Source terms of released respirable aerosols are evaluated for two reference cases, borehole drop (impact velocity v = 80 m/s) and reloading hall drop (v = 14 m/s), the values being 0.1 % and to 2.10-4 % respectively of the glass probe mass. The full scale drop tests are performed with European Standard HLW canisters. The canisters keep their integrity in all tests up to drop heights of 14 m. On opening the canisters, the broken fines are analyzed by sieving. The results are in good agreement with the small scale tests and confirm their acceptability for use in a safety analysis.

Assessment of PAH emissions as a function of coal combustion variables in fluidised bed. 2. Air excess percentage

Fuel ◽  
1998 ◽  
Vol 77 (13) ◽  
pp. 1513-1516 ◽  
Author(s):  
Ana M. Mastral ◽  
Marisol Callén ◽  
Ramón Murillo ◽  
Tomás García
Keyword(s):  
Coal Combustion ◽  
Fluidised Bed

Model Research of Gas Emissions From Lignite and Biomass Co-Combustion in a Large Scale CFB Boiler

2014 ◽  
Vol 35 (2) ◽  
pp. 217-231 ◽  
Author(s):  
Jarosław Krzywański ◽  
Rafał Rajczyk ◽  
Wojciech Nowak
Keyword(s):  
Experimental Data ◽  
Coal Combustion ◽  
Large Scale ◽  
Forest Biomass ◽  
Fluidised Bed ◽  
Fuel Blend ◽  
Energy Fraction ◽  
Cfb Boiler ◽  
Fuel Blends ◽  
Combustion Modelling

Abstract The paper is focused on the idea of a combustion modelling of a large-scale circulating fluidised bed boiler (CFB) during coal and biomass co-combustion. Numerical computation results for three solid biomass fuels co-combustion with lignite are presented in the paper. The results of the calculation showed that in previously established kinetics equations for coal combustion, some reactions had to be modified as the combustion conditions changed with the fuel blend composition. Obtained CO2, CO, SO2 and NOx emissions are located in borders of ± 20% in the relationship to the experimental data. Experimental data was obtained for forest biomass, sunflower husk, willow and lignite cocombustion tests carried out on the atmospheric 261 MWe COMPACT CFB boiler operated in PGE Turow Power Station in Poland. The energy fraction of biomass in fuel blend was: 7%wt, 10%wt and 15%wt. The measured emissions of CO, SO2 and NOx (i.e. NO + NO2) were also shown in the paper. For all types of biomass added to the fuel blends the emission of the gaseous pollutants was lower than that for coal combustion.

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