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Variations in sulphur and nitrogen foliar concentration of deciduous and conifers vegetation in Slovakia
1997
Maňkovská, Blanka
The foliage contents of Sₜₒₜₐₗ and Nₜₒₜₐₗ were determined in 405 Permanent monitoring plots in four National Parks and sixteen Landscape Protection Areas and were compared with 1483 Permanent monitoring plots on Slovakia. The foliage content of S ranged from 0.72 to 6.77 g kg⁻¹ in hardwoods and from 0.98 to 4.3 g kg⁻¹ in softwoods. A critical increase was determined in one National Park and in four Landscape Protection Areas. The foliage content of N ranged from 9.7 to 48.7 g kg⁻¹ in softwoods, and from 7.8 to 51.4 g kg⁻¹ in hardwoods. An insufficient level of N was determined in one Landscape Protection Area and a critical increase in four Landscape Protection Areas. The sulphur to nitrogen ratio ranged from 0.08 to 0.176 in softwoods, and from 0.078 to 0.253 in hardwoods. The foliage surface on hitherto explored four National Parks and sixteen Landscape Protection Areas in network 4×4 km was covered by all categories of rigid fallout particles. Fly-ash from coal combustion were observed each of National Parks and Landscape Protection Areas by scanning electron microscopy. Mycelia and spore, mineral matters, sand and soil particles were present on all National Parks and Landscape Protection Areas. Particles derived from aluminium production were observed at three Landscape Protection Areas. Particles derived from cement production and from lime works were observed at two National Parks and six Landscape Protection Areas. Particles derived from ferrous metals industry were observed at each of National Parks and Landscape Protection Areas and particles typical for other technologies were present in three of National Parks and twelve Landscape Protection Areas.
Afficher plus [+] Moins [-]Zero test emissions of sulphur dioxide from large coal under staged fluidized bed combustion
1997
Khan, W. Z. | Gibbs, B. M.
This paper reports the emissions of SO₂ from large coal under staged combustion without any additive. A stainless steel combustor, 2 m high and 0.3×0.3 m in cross section was used. Fluidizing air was supplied through a multihole distributor. An adjustable secondary air injector was used along the vertical axis of the combustor to introduce secondary air in the freeboard. From 0–40% of total air was injected in the freeboard above the bed. The experiments were carried out at fluidizing velocities of 1–2 m s⁻¹, bed temperatures of 1103–1153°K, 20–40% excess air, and bed particle sizes of 665μm. Bed temperature and level of air staging had the most significant effect on SO₂ emissions.
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