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- 1. ACHIEVE 99% SULPHUR RECOVERY AS SULPHURIC ACID IN ITS
SIMPLEST CONFIGURATION. Dr. Rania Farouq Abdou Ahmed Sharif Amr
Elshaikh Mohamed Asaad Magdy Zaref Moataz Satour
- 2. Dr. Rania Farouq Abdou 1 TREATMENT OF N.G BY SULFOX ACHIEVE
99% SULPHUR RECOVERY AS SULPHURIC ACID IN ITS SIMPLEST
CONFIGURATION. Introduction SULFOX process is one of the methods of
treating Natural Gas, and its a DIRECT CONVERSION PROCESS. What is
sulfox process? Sulfox is a gas desulfurization process which
converts sulfur that is in raw gas to concentrated sulfuric acid.
Main features: 1. Catalytic oxidation of the sulfur compounds to
SO3 and formation of sulfuric acid 2. Various types of plants for a
wide range of raw gas concentrations 3. High efficiency of the
noble metal catalyst 4. Recovery of commercial grade sulfuric acid
5. No usage of chemicals, no emission of toxic substances. 1.
Operate the facility continuously and reliably 2. Economically
create products meeting the markets quality standards 3 .Sell the
products to the market
- 3. Dr. Rania Farouq Abdou 2 Operation-Technology MECS SULFOX :
A SULFOX sulphuric acid plant can achieve 99% sulphur recovery as
sulphuric acid in its simplest configuration. More complicated flow
schemes utilising activated carbon filters or a DynaWave tail gas
scrubber can achieve much higher sulphur recovery values and
ultra-low SO2 emissions. A SULFOX plant can be installed in lieu of
a Claus SRU and TGTU or as part of an integrated complex with a new
or existing Claus SRU and TGTU. When integrated in this way, a
SULFOX plant increases flexibility and reliability by
debottlenecking acid gas capacity, processing SWS gas to eliminate
ammonia concerns, providing additional Claus SRU tail gas clean up,
and handling all acid gas when the Claus SRU is down. process 1.
The feed gas, after being oxidised to SO2 and brought to the
correct temperature. 2. passes through a converter containing
vanadium and caesium-promoted catalyst and internal heat
exchangers. 3. The equilibrium reaction of SO2 to SO3 occurs across
multiple catalyst beds. 4. with heat exchangers removing the
reaction heat between each bed to increase the SO2-to-SO3
conversion level. 5. The final heat exchange step in the converter
lowers the process gas temperature to a level above the sulphuric
acid condensation point (acid dewpoint). 6. and the gaseous SO3
reacts with H2O vapour to form sulphuric acid vapour.
- 4. Dr. Rania Farouq Abdou 3 PROCESS CONDITIONS The feed gas
oxidation, and heating or cooling steps of a SULFOX plant depend on
the acid gas concentration and composition. For applications with
>5 vol% H2S or significant quantities of hydrocarbons or
ammonia, a SULFOX HK process thermally oxidises the feed gas at
high temperature. SULFOX HK process & SULFOX NK process The
HK-type plant provides the maximum feed gas flexibility at the
trade-off of a larger, more expensive and complicated plant due to
the combustion and steam systems. An NK-type plant offers a simple,
inexpensive, and reliable process but places limits on the
allowable feed gas composition.
- 5. Dr. Rania Farouq Abdou 4 A SULFOX HK process suits most acid
gas treatment facility applications. Table 4 highlights the
relative comparison for a lower concentration H2S acid gas feed,
which would require modifications to a typical Claus process to
reliably treat. The SULFOX process offers substantial capital and
operating cost benefits compared to a Claus SRU and TGTU
combination. Process Benefits 1. Process Benefits: Recovery and
recycle of SO2 to the Claus SRU 1) Provides attractive
debottlenecking and expansion opportunities in the Claus SRU for
existing facilities 2) Reduces capital expense and plot space
requirement for grassroots facilities 2. Solvent Benefits: Unique
absorption solvent a. Readily available and cost-effective b.
Environmentally friendly c. Virtually eliminates waste associated
with traditional scrubbers 3. Guaranteed ultra-low SO2 emissions
(less than or equal to 20 ppmv SO2) Summary Many options are
available for treating sour gases, so consideration must be given
to the type of by-product (sulphate effluent, sulphur or sulphuric
acid), local markets for these products, shipping costs, overall
sulphur recovery required and economics. The Claus SRU process is
clearly the predominant choice for treating acid gases, presumably
due to the well-established sulphur marketing and shipping
infrastructure, ease of handling and economics. However, converting
acid gases to sulphuric acid with technologies like the MECS SULFOX
process presents an interesting option when sulphuric acid
end-users are nearby or the acid gas characteristics make
processing in a Claus SRU unit unattractive.