sulfur recovery and tail gas hydrogenation
37 thousand t/year sulfur recovery unit:
The designed elasticity is 35~120%, start time is 8000h/year, sulfur recovery rate is more than 99.9%, sulfur production/year is 37 thousand, sulfur quality confirms to the national standard GB/T2449 premium product quality indexes (if the arsenic content in raw gas satisfies the requirements, the arsenic index in product must be ensured). SO2 concentration in final emission flue gas after treatment is less that 30mg/Nm3, less than the requirements of the latest.
sulfur recovery and tail gas hydrogenation
15 thousand t/year sulfur recovery unit:
The designed elasticity is 30~110%, start time is 8000h/year, sulfur recovery rate is more than 99.9%, sulfur production/year is 15 thousand, sulfur quality confirms to the national standard GB/T2449 premium product quality indexes (if the arsenic content in raw gas satisfies the requirements, the arsenic index in product must be ensured). SO2 concentration in final emission flue gas after treatment is less that 30mg/Nm3, less than the requirements of the latest.
quality indexes of catalysts and operating conditions
The picture is A988 TiO2-based sulfur recovery catalyst and A918 Claus sulfur recovery catalyst.
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Project |
Quality indexes |
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Type |
A918 |
A958 |
A988 |
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Chemical composition |
Al2O3 ≥92 |
Al2O3 |
TiO2 >85 |
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Appearance |
White sphere |
Red-brown sphere |
White strip |
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Specification, mm |
Φ4~6 |
Φ4~6 |
Φ4±0.5×5~20 |
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Specific surface area, m2/g |
≥300 |
≥260 |
≥100 |
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Bulk density, kg/L |
0.65~0.80 |
0.75~0.85 |
0.90~1.05 |
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Compressive strength, N/granule |
≥140 |
>130 (N/granule) |
≥100 |
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Pore volume, ml/g |
≥0.4 |
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Wear rate |
≤0.5 |
≤0.5 |
<1.0 |
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A999 |
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Project |
Unit |
Index |
|
MoO3 |
%(m/m) |
10~12 |
|
CoO |
%(m/m) |
1.8~2.5 |
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Appearance |
Blue-gray strip |
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Specification |
mm |
Φ3~5 |
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Specific surface area |
m2/g |
≥260 |
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Pore volume |
ml/g |
≥0.35 |
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Bulk density |
g/cm3 |
0.50~0.70 |
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Radial strength |
N/cm |
≥120 |
performance assessment indexes
The picture is A999 Co-Mo hydro-desulfurization catalyst.
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No. |
Name |
Performance requirements |
Note |
|
|
1 |
A958 A918 A988 |
At the mentioned condition: 1. space velocity is more than 800h-1 2. balanced conversion rate is more than 98%, total conversion rate of Claus sulfur production part is more than 95% 3. A988 during lifetime, hydrolysis rate is more than 95% |
1. resistance drop of catalyst bed should less than 2 Kpa, resistance at early-stage and end-stage use should remain 2. catalyst quality standards satisfies the requirements mentioned |
Lifetime ≥4years |
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2 |
A999 |
At the mentioned condition: 1. space velocity is more than 1200h-1 2. inlet gas flow of tail gas hydrogenation reactor should not detect sulfide that non-H2S, COS <20ppm (v) |
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loading and effect
Sulfur recovery catalyst is utilized for the high-temperature reaction of section 1 and the partial combustion process of catalytic conversion of section 2; tail gas hydrogenation catalyst is utilized for the hydrogenation reduction absorption process for sulfur recovery tail gas
37 thousand t/year sulfur recovery unit:
The loading height of one & two stage convertors is 800mm, the 2/3 lower part of one-stage convertor loads A988 and the 1/3 upper part loads A958; two-stage convertor loads A918; the height of hydrogenation reactor is 800mm, loads A999; supporting protection agent loads on the lower (φ10/φ16 each has half) and upper (φ16) part of catalyst, loading height are 100mm
Advising loading measure:
(1) one-stage convertor (R-101)
Upper part: φ16 inert ceramic ball 100mm
Middle part: A958 265mm (8.7m3)
A988 535mm (17.5m3)
Lower part: φ10 inert ceramic ball 50mm
Φ16 inert ceramic ball 50mm
(2) two-stage convertor (R-102)
Upper part: φ16 inert ceramic ball 100mm
Middle part: A918 800mm (24.8m3)
Lower part: φ10 inert ceramic ball 50mm
Φ16 inert ceramic ball 50mm
(3) hydrogenation reactor (R-201)
Upper part: φ16 inert ceramic ball 100mm
Middle part: A999 800mm (18.4m3)
Lower part: φ10 inert ceramic ball 50mm
φ16 inert ceramic ball 50mm
15 thousand t/year sulfur recovery unit:
The upper part of one-stage convertor loads 3.5m3 A958, the lower part loads 7.5m3 A918; two-stage convertor loads 11m3 A918; tail gas hydrogenation reactor loads 7m3 A999
1. A918 and A958 loading cautions
(1) loading at the dry condition, avoid loading at conditions that in rainy weather or environmental humidity is higher to protect the strength
(2) before loading, clear the inner of reactor and place the grate plate, place 5 meshes steel net, successively place 100mm, φ20mm ceramic ball and 50mm, φ10mm ceramic ball, then loading the catalyst. Require that the grate plate and net can be used for at least 3years
(3) during loading, take catalyst into bag and then hanging into reactor, fallen height should less than 500mm
(4) there should place wood board during loading, the loading staff should stand on it to operate, using metal tools to dig catalyst is prohibited. After loading to the predetermined height, it should use wood tools to pave nicely the catalyst surface and place a layer of 50mm, φ10mm ceramic ball to reduce the impact of the catalyst surface by gas flow
(5) the inlet should be sealed after loading, avoid water steam and process gas into reactor, clear with dry gas to remove the bed powder before start
2. A999 loading cautions
loading at the dry condition, avoid loading at conditions that in rainy weather or environmental humidity is higher to protect the strength
(1) before loading, clear the inner of reactor and place the grate plate, place 5 meshes steel net, successively place 100mm, φ20mm ceramic ball and 50mm, φ10mm ceramic ball, then loading the catalyst. Require that the grate plate and net can be used for at least 3years
(2) catalyst is put out from drum, if there has much powder, it should be used after sieving by more than 10 meshes sieve. When loading, take catalyst into bag and then hanging into reactor, fallen height should less than 500mm
(3) there should place wood board during loading, the loading staff should stand on it to operate, using metal tools to dig catalyst is prohibited. After loading to the predetermined height, it should use wood tools to pave nicely the catalyst surface and place a layer of 50mm, φ10mm ceramic ball to reduce the impact of the catalyst surface by gas flow
(4) the inlet should be sealed after loading, avoid water steam and process gas into reactor, clear with dry gas to remove the bed powder before start
