The document discusses how refiners face a "sulphur paradox" as crude oils contain increasing sulphur but fuel specifications restrict sulphur emissions. It describes Shell's Sulphur Technology Platform which provides integrated technologies and customized solutions to help refiners process high-sulphur feeds and meet environmental regulations. These include hydroprocessing catalysts, sulphur recovery processes, and gas treating systems from Shell and partner companies. Case studies demonstrate how the solutions have helped refineries produce low-sulphur fuels and reduce emissions.

1. The reduced availability of light and sweet crudes, and the
consequential increase in the cost of such feedstocks, makes it
more and more attractive for refiners to take in heavier and
sourer feeds.
However, there are consequences. Refiners that use higher-
sulphur crudes can find it extremely challenging to respond to
trends such as:
n increasingly stringent fuel specifications
n diminishing fuel oil market
n tightening emissions regulations
This sulphur paradox, namely that more sulphur is coming
into the refinery (as the availability of sweet crudes
diminishes) but less must leave the refinery within the
finished products or as harmful emissions. There is never a
silver bullet solution: a flexible and tailored approach is
necessary to account for individual circumstances such as
n seasonal product demand shifts;
n changes in crude slate;
n the availability of capital;
n local market conditions; and
n individual unit design differences.
Intelligently applied, leading-edge technology, and a
robust sulphur management strategy is imperative.
About the technology
Shell Global Solutions provides a comprehensive solution
to help refiners to meet their specific short- and long-term
business goals. Initial consultancy and extended services
throughout the project life cycle may include:
n market studies, such as scenario planning and
masterplanning to help take a view of the future market
and to enable more robust decision making regarding
location, feedstock, logistics, process configuration and
hardware requirements;
n front-end development to optimise process design and
technology selection;
n implementation support, such as project management
support and contractor management to ensure budgets
and schedules are met; and
n start-up and commissioning services to reduce the time
to reach optimal operations, and organisational
effectiveness reviews.
AT A GLANCE
Customer driver: Legislative constraints (permits/licence to
operate, fuel specifications); margin improvement (optimised
production, efficiency and availability); changing feedstock
slate (heavy/sour/high TAN/syn crudes)
Solution: A comprehensive portfolio of integrated, best-in-
class technologies customised to meet a refiner’s specific
business objectives
Value delivered: Enhanced yield of high-value
products; ability to process sourer crudes; optimised
environmental footprint.
Proof point: Over 100 years of experience as one of the
technology pioneers
Shell Sulphur Technology Platform
Consultancy and technologies to help take control of the sulphur paradox
Shell Global Solutions
Today’s feedstocks typically
contain increasing levels of
sulphur, but fuel specifications
are tightening – This is the
sulphur paradox.

2. Through our Sulphur Technology Platform strategy, we
can provide a portfolio of integrated, comprehensive
technology solutions to meet your specific needs. We
license a suite of technologies that can deal with sulphur
in various forms (Figure 1). These are:
n sulphur in crude;
n sulphur in all products, from liquefied petroleum gas
(LPG) to residue;
n hydrogen sulphide (H2
S);
n sulphur dioxide (SO2
);
n mercaptans; and
n solid sulphur.
Various characteristics set Shell Global Solutions apart
from other licensors in this area. The Shell Sulphur
Technology Platform is:
n comprehensive. We have a wide range of catalysts and
technologies.
n integrated. This enables the process configuration to be
optimised across the refinery.
n customised. Solutions can be tailored to meet a refiner’s
short- and long-term business goals.
The Shell Global Solutions licensing portfolio includes
technologies from key, carefully selected companies.
For instance, solutions may incorporate:
n Criterion Catalysts Technologies’ hydroprocessing
catalysts;
n Zeolyst International’s hydrocracking catalysts;
n Merichem Company’s liquid treating technologies;
n Cansolv Technologies Inc.’s SO2
scrubbing and carbon
dioxide (CO2
) removal technologies;
n Praxair, Inc.’s CONOx technology;
n CDTECH’s fluidised catalytic cracking (FCC) gasoline
selective hydrodesulphurisation technology; and
n Sandvik’s sulphur solidification and handling systems.
Criterion and Cansolv are wholly owned by Shell.
CDTECH and Zeolyst are Shell joint ventures.
Performance data
Continuous research and development has helped to
improve the relative volume activity of Criterion’s
market-leading desulphurisation catalysts by a factor
of five.
The SCOT process enhances sulphur recovery from
Claus plants to over 99.8%, thereby helping facilities to
meet even the most stringent environmental limits,
including World Bank standards.
Merichem liquid treating technologies offer key
advantages, including high-performance impurity
removal and smaller processing vessels, and require
reduced capital expenditures.
CANSOLV SO2
scrubbing technology can achieve SO2
emissions as low as 10 ppmv, depending on the design
parameters, and produces minimal effluent.
Business value
Shell Global Solutions supports customers through the
crucial front-end development phase – where decisions
are critical and have a strong influence on the overall
project value. We bring our experience and
Figure 1: The Shell Sulphur Technology Platform.

3. Technologies Technology developer Application
Hydroprocessing and
Catalysts
Shell Global Solutions,
Criterion, CRI, Zeolyst
Hydroprocessing applications, including:
n naphtha hydrotreating;
n kerosene hydrotreating;
n diesel hydrotreating and;
n hydrocracking.
In addition we offer catalysts for residue hydrotreating fixed and
ebullating bed, and selective catalytic reduction of nitrogen oxide
(NOx) from furnaces, heaters, boilers and turbines.
Gas/liquid treatment
and sulphur recovery
technologies
Shell Global Solutions The ADIP‡
process removes H2
S from refinery gases and the SCOT‡
process enhances sulphur recovery from Claus plants to over 99.8%,
thereby helping facilities to meet even the most stringent
environmental limits.
The sulphur degassing process is used to remove H2
S from the liquid
sulphur produced in Claus sulphur recovery units.
Liquid treating
technologies
Merichem THIOLEX™
: Caustic extraction of acid gas and mercaptan compounds
from liquid and gas hydrocarbon streams.
THIOLEX COS: Caustic/catalyst extraction of acid gas and carbonyl
sulphide (COS) compounds from liquid and gas hydrocarbon streams.
REGEN®
: Regeneration of rich caustic streams to improve caustic
utilisation.
REGEN ULS: Regeneration of mercaptide-rich caustic.
MERICAT™
and MERICAT C: A caustic/catalyst/air mixture removes
hydrogen sulphide and sweetens mercaptan compounds in gasoline,
naphtha, condensate and crude oil streams.
MERICAT J: A special solution mixed with air oxidises heavy
mercaptans in jet fuel and middle distillate streams without the need
for a fixed carbon bed.
MERICAT II: A caustic/catalyst/air mixture removes hydrogen sulphide
and sweetens mercaptan compounds in jet fuel, kerosene and gasoline
and naphtha streams.
NAPFINING™
and NAPFINING HiTAN: Caustic extraction of
naphthenic acid compounds from jet fuel, kerosene, diesel,
condensate and crude oil streams.
EXOMER™
: A proprietary treating reagent removes the recombinant
mercaptans that form in selectively hydrotreated FCC gasoline or heavier
molecular weight mercaptans from liquid hydrocarbon streams.
AQUAFINING™
: Water extraction of soluble organic and inorganic
impurities from liquid and gas hydrocarbon streams.
MERICON™
: On-site solutions for the processing of spent caustics
to reduce their biochemical oxygen demand and chemical oxygen
demand, control odour and adjust acidity.
CHLOREX™
: Alkaline water extraction of inorganic chloride
compounds from reformer gas and liquid product streams.
AMINEX™
and AMINEX COS: A special amine removes acid gas and
COS compounds from LPG-type and gas streams.
CANSOLV®
SO2
scrubbing
Cansolv For the control of emissions and to capture additional by-product
value from flue gas streams generated by FCC units, process heaters,
sulphur plants and spent acid regeneration units
CANSOLV®
CO2
removal Cansolv For the bulk removal of CO2
from post combustion flue gas streams.
When integrated with the CANSOLV SO2
scrubbing system, this
reduces parasitic energy consumption.
Praxair CONOx
Technology
Praxair An innovative solution for controlling carbon monoxide (CO) and
NOx emissions from FCC units
FCC gasoline selective
hydrodesulphurisation
technology
CDTECH Catalytic distillation technology that processes FCC gasoline streams
to produce a stream that is essentially free of mercaptans.
Sulphur solidification and
handling systems
Sandvik Complete turnkey project solutions for sulphur pastillation and
handling plants are available
‡
ADIP and SCOT are Shell trademarks.
EXOMER, MERICAT, MERICAT II, MERICON, NAPFINING, REGEN ULS and THIOLEX
are service marks of Merichem.
REGEN is a trademark of Merichem Company.
CANSOLV is a trademark of Cansolv Technologies Inc.
Process description

4. techniques, such as scenario planning and
masterplanning, so that value is built in from the start.
We then work with customers to provide optimised
technical solutions that can help them to:
n reduce the sulphur levels of their products, from
gasoline and diesel through to LPG and jet, to meet
product specifications;
n remove H2
S, SO2
, and CO2
from their off-gases to meet
their environmental mandate;
n process opportunity crudes, which represent an
additional revenue opportunity; and
n reduce the production of residue and fuel oil.
Moreover, our support does not end with the delivery of
a set of recommendations. We also spearhead their
implementation and remain with customers until they see
the benefits.
HAvE yOu CONsidErEd HOw yOu CAN
n react as the marine fuels specifications tighten?
n increase the capacity of your sulphur recovery unit?
n maximise the use of high-sulphur residue fuels?
For more information, please visit our website at www.shell.com/globalsolutions
All statements regarding Merichem Company and Praxair, their affiliates and their products are based
solely on information provided by Merichem Company and Praxair. Inc. and have not been
independently verified by Shell Global Solutions.
Shell Global Solutions is a network of independent technology companies in the Shell Group. In this
material, the expressions “Shell” and “Shell Global Solutions” are sometimes used for convenience
where reference is made to these companies in general, or where no useful purpose is served by
identifying a particular company.
The information contained in this material is intended to be general in nature and must not be relied
on as specific advice in connection with any decisions you may make. Shell Global Solutions is not
liable for any action you may take as a result of you relying on such material or for any loss or
damage suffered by you as a result of you taking this action. Furthermore, these materials do not in
any way constitute an offer to provide specific services. Some services may not be available in certain
countries or political subdivisions thereof.
Copyright ©
2010 Shell Global Solutions International BV. All rights reserved. No part of this
publication may be reproduced or transmitted in any form or by any means, electronic or mechanical
including by photocopy, recording or information storage and retrieval system, without permission in
writing from Shell Global Solutions International BV.
GS33331110 En(A)
pRoof poINTs
CIS refiner revamps for ultra-low-sulphur
diesel (ULSD)
A CIS refiner was producing 350-ppm diesel but
needed to adapt in order to produce 50-ppm diesel
(Euro IV product specifications) in 2012. To achieve a
no-regret investment, the company was also looking
ahead to the requirement to meet Euro V in 2015.
The solution involved expanding the volume of
catalyst and replacing the catalyst with a more active
ULSD catalyst and a new dewaxing catalyst to
improve the diesel’s cold flow properties. The
application of Shell’s wash-water design helped to
combat fouling and corrosion issues. This involved
capital expenditure of about $10–15 million
(excluding the first catalyst fill) and could be worth
$8 million in annual margin to the refiner.
US refiner meets stricter SO2
regulations
Faced with stricter SO2
regulations, a refinery in
California, USA, needed to find an alternative
solution to treat the tail gas of its alkylation spent acid
regeneration plant, as the existing ammonium
sulphate process was troublesome and did not
integrate well with the refinery sulphur product chain.
A Cansolv SO2
scrubbing system was selected to
replace the existing ammonium sulphate system.
Since the unit’s start-up in 2002, performance has
exceeded the targeted design conditions. The refiner
has decoupled the operation of the acid plant from
its SO2
emissions by exploiting the technology’s
ability to treat a range of inlet SO2
concentrations.
The Cansolv SO2
scrubbing system has consistently
met SO2
emissions of 20 ppmv or less while treating
acid plant tail gas with SO2
content as high as
6,000 ppmv.
A comprehensive portfolio of
integrated technologies, derived
from and fine-tuned using real
business challenges, that can be
customised to meet your specific
business needs.