该技术系统是由英荷壳牌集团的成员之一，CRI（Catalyst Regeneration
International）国际公司下属的全资子公司CRI催化剂公司开发的。CRI的总部设在美国休斯顿。1998年营业额5亿美元，主要从事炼油、石油化工和化工催化剂生产、销售和技术服务业务。
CRI催化剂公司（CRI Catalyst
Company）主要从事环氧乙烷催化剂、脱NOx催化剂、脱VOx催化剂的生产与销售，同时还进行技术转让。在比利时根特和美国马丁内兹有两家生产厂。
CRI处理烟气的催化剂系统主要有三种：
壳牌低温氮氧化物去除系统(SDS)
CRI为各种静止火源和化工过程所产生的氮氧化物(NOx)提供壳牌低温氮氧化物去除系统(Shell DeNOx System,
SDS)。CRI特别研发的脱硝技术具备高效率、低工作温度的有利条件，特别在改建低温设备的情况下突出低成本的优势。
NOx Reduction CRI Selective Catalytic (SCR) NOx Reduction
Technology
Since its
commercial introduction in the 1970's,Selective Catalytic Reduction
(SCR) of nitrogen oxides (NOx) has gained wide acceptance worldwide
as the most effective and technologically proven method for
high-percentage NOx removal from flue gases.
CRI's
technology, known as the Shell DeNOx System (SDS), operates on the
SCR principal. It uses ammonia (NH 3) as the reductant and a
catalyst to promote the reaction of NH 3 with NOx, forming nitrogen
and water.
An efficient
retrofit
The CRI SCR
catalyst can operate at lower temperatures and with lower pressure
drop than conventional SCR catalysts. Consequently, the CRI SCR
system can be installed immediately before or in the stack, thereby
avoiding any modifications to combustion or heat-recovery equipment
or negative effects on other upstream plant operations. This makes
the CRI technology very cost-effective for retrofit SCR
applications.
Typical
Application Conditions and Performance of the CRI Low-Temperature
SCR Technology:
Operating Temperature
Typical Application
325-450° F /160-230° C
Range
300-700° F/ 150-375° C
Pressure Drop
Typical Application
2-3 in. H2O/ 5-7.5 mbar
Range As low
as 1 in. H2O/2.5 mbar
Performance
NOx Conversion
>90%
NH3Slip 5-10
ppm or lower
Unique
catalyst and module technology
The CRI
technology differs from conventionalSCR systems in two important
aspects: the catalyst and the catalyst reactor module. The catalyst
is in the form of pellets and can be produced in a range of sizes
and shapes to meet specific performance requirements. Due to the
high activity of the catalyst, high NOx removal efficiencies with
simultaneous control of NH3 slip can be obtained at relatively low
temperatures.
The catalyst
reactor module is based on the Lateral Flow Reactor (LFR)
principal. The LFR is a packed-bed type reactor which offers the
advantage of low pressure drop even at high space velocities.
Furthermore, the LFR design makes possible the most efficient
utilization of the SCR catalyst, which minimizes the amount of
catalyst required and facilitates fast loading and unloading of
catalyst from the reactor.
Development
of the LFR technology has resulted in a modular construction
system, providing a high degree of flexibility in the design of SCR
systems for specific applications, particularly retrofit.
A broad
range of applications
The CRI SCR
technology has been successfully applied to combustion and chemical
process operations including gas turbines, refinery heaters,
boilers, ethylene cracker furnaces, nitric acid plants and waste
incineration facilities.
Resulting
from the high catalyst activity and flexibility of the LFR module
design, the optimal and most cost-effective combination of NOx
removal, NH 3 slip, temperature, pressure drop and available plot
or duct space can be developed for virtually any
application.
去除氮氧化物系统（SDS）——世界上{zh0}的低温脱硝技术和系统
SCR催化剂，采用独特的侧流方式，具有效率高、压降小（<10~20mbar）、工作温度低（130~380℃）实际的造价和使用的成本低；氮氧化物的排除量<10~50PPMV，可去除60~98%氮氧化物；可按要求设计，广泛地应用于硝酸厂、已内酰胺厂、燃气轮机、燃煤燃气锅炉、垃圾焚烧炉、炼油厂加热炉、乙烯裂解炉等。
壳牌二恶英去除系统
(SDDS)
CRI为城市固废及危险废液焚烧处理设备产生的二恶英提供壳牌二恶英去除系统 (Shell Dioxin Destruction
System, SDDS)。SDDS实现成本低，效率高的成功方案，能让客户达到最严格的二恶英排放标准。
CRI Catalytic Dioxin Destruction Technology
Dioxins
Dioxins
comprise a family of over 200 chemical compounds known as
persistent organic pollutants, harmful by-products of industrial
processes and waste incineration. Major sources of dioxin emissions
include municipal solid, industrial liquid and medical waste
incineration, as well as some chemical and metal sintering
operations.
Dioxins are
potent carcinogens; their adverse effects also include
neurological,
developmental, reproductive and immunotoxic
effects.
The Shell Catalytic Dioxin Destruction System (SDDS) from CRI is a
proven low-temperature technology for flue gas dioxin emission
destruction, with excellent cost/performance benefits compared to
other dioxin emission control technologies.
The Shell
Dioxin Destruction System
Single-step
simplicity
Unlike
technologies based on carbon adsorption, the CRI catalytic system
destroys dioxin compounds in a single process step, with no
subsequent processing needed. In addition, the CRI process does not
require the addition of any reactant beyond the oxygen already in
the flue gas. The CRI system uses a specially developed catalyst to
convert dioxins to a mixture of harmless
gases.
Low emissions at low temperatures
The CRI
dioxin destruction catalyst enables dioxins to be reduced to
extremely low levels at low flue gas temperatures, even as low as
320° F (160° C).
Unique
reactor design
The CRI
dioxin destruction catalyst is contained in engineered stainless
steel modules called lateral flow reactors, which expose the
greatest amount of catalyst surface to the flue gas which gives the
highest performance with lowest pressure drop.
High
destruction efficiency
The
combination of high catalyst activity with the lateral flow reactor
allows the Shell Dioxin Destruction System to easily achieve high
dioxin destruction efficiency. From the highest inlet
concentrations, the system can achieve over 99.9% destruction of
dioxins and furans, down to the lowest worldwide regulated emission
limit of 0.1 ng TEQ NM3.
Flexible
applications
The CRI
catalytic dioxin destruction technology has been successfully
applied to both liquid waste incinerators after the wet acid gas
scrubber, and to solid waste incinerators after the acid gas and
particulate removal systems. The low-operating temperature and the
ability to design for low pressure drop allow the Shell Dioxin
Destruction System to be positioned at the tail end of most
existing processes, just prior to the stack.
The Shell
Dioxin Destruction System Process Flow Chart
Solid Waste
Incineration
Application
Hazardous
Liquid Waste Incineration Application
Easy retrofit
The compact,
lightweight nature of the system allows easy retrofit onto existing
facilities where space is limited. Installation at the end of the
process results in significant savings in installation and
operating costs, with minimal downtime for
installation.
先进环保工艺：
壳牌去除二恶英系统（SDDS）选择性催化技术可以在低温下（100ºC）去除高达99.99%的二恶英，可达到0.01Ng/Nm³的世界{zg}标准。它的结构与SDS相同，采用独特的侧流式，即气体要透过侧面的催化剂层流出去；壳牌的催化剂的活性是其他催化剂的活性的2-5倍，并且是多孔的，这样就增大了接触面积。目前有30多套系统在世界各地的医疗垃圾、工业民用垃圾的焚烧炉、焦化厂等。
安装位置：
壳牌SDDS系统，可以安装在尾气的前后，无论在什么位置，SDDS系统均能保持极小的压力降，对生产的影响极小。
主要优点：
1、适宜温度从130-380ºC，常用的温度160-210ºC；
2、二恶英排出可以小于每立方米0.01纳克,和去除{zg}达99.99%的二恶英；
3、不需要任何的反应剂和添加剂；
4、 结构紧凑,体积小；安装简便,快到停产几天就可安装完成；
5、催化剂活性高，一次性投入,可用5-8年；
6、可同时去除垃圾焚化中产生的氮氧化物。
大致反应方程式： C12HnCl8-nO2+(9+0.5n)O2
=(n-4)H2O+12CO2+(8-n)HCl
CRI氧化亚氮减排系统
CRI能为硝酸、己内酰胺、己二酸及其它行业提供高效的氧化亚氮减排系统，进而通过减排量换取碳信用额和财务收入，争取经济、环保两益双收。
N2O Decomposition
N2O
Nitrous
Oxide (N2O) is formed and emitted into the atmosphere in
significant concentrations from several industrial chemical
processes, in particular the production of nitric acid, caprolactum
and adipic acid. N2O is a strong greenhouse gas (GHG) and has a
global warming potential of 310 times higher than CO2. In the Clean
Development Mechanism (CDM) countries under the Kyoto Protocol, N2O
is included as a GHG and N2O reduction projects can be used to
generate tradable carbon credits and financial revenues.
CRI N2O
Decomposition Technology
The CRI N2O
Abatement Technology (C-NAT) is a catalytic technology for the
decomposition of nitrous oxide (N2O) in chemical streams.
The CRI
technology is a direct N2O decomposition process that does not
require the addition of any reducing agent or other reactant. N2O
destruction of 90% or higher can be achieved over a range of
temperatures and pressures. No undesirable byproducts are
formed.
The catalyst does not form other oxides of nitrogen such as NO or
NO2.
Applications
for the CRI N2O abatement technology include the tail gas from
nitric acid, caprolactam and adipic acid plants. The CRI N2O
decomposition technology is highly effective under the range of
operating conditions and tail gas compositions typically found in
such plants.
Typical
Application and Performance of the CRI N2O Abatement
Technology
Operating
Temperature
Typical Application 475 - 525° C / 885 - 975°
F
Range 450 - 650° C / 840 - 1200° F
Pressure 1-12 bara
N2O Concentration 500-2000 ppm
N2O Destruction 70 – 95%
N2O
Abatement System
The CRI N2O
destruction catalyst is in the form of pellets.
The catalyst is contained in a reactor module which is based on the
Lateral Flow Reactor (LFR) principle. The LFR is
a packed-bed type reactor in which the catalyst pellets are
contained in thin layers between gas channels.
The flue gas is forced laterally through the catalyst layers which
makes possible the most efficient utilization of the catalyst and
which minimizes pressure drop even at high space velocities.
The catalyst
modules are housed in a reactor house, typically in a single layer,
which provides support to the modules as well as sealing around the
modules to insure all of the gas passes through the catalyst
bed. The reactor house can be atmospheric or the
catalyst modules can be incorporated inside of a pressure vessel
for high pressure applications. The reactor house
can be designed for vertical up or down flow or horizontal
flow.
The CRI N2O process does not require the addition of any reducing
agent or other reactant.
The CRI N2O
catalyst is stable in the presence of NOx (NO + NO2) and ammonia
(NH3) so that it can be located upstream or downstream of a
selective catalytic NOx reduction (SCR) system.
If the tail
gas temperature is lower than the optimum temperature range of the
CRI technology, flue gas reheat with associated heat recovery can
be installed upstream of the catalyst reactor to optimize process
economics.
N2O
Decomposition: Nitric Acid Plants
N2O
emissions from nitric acid plants can range from about 2 to 20 kg
(5 to 50 lbs) per ton of HNO3 or up to 3500 ppm concentration in
the tail gas, depending on the nitric acid process and plant
operating conditions. The CRI N2O catalyst technology is highly
effective in significantly reducingN2O emissions from nitric acid
plants. N2O destruction of 90+% can be achieved.
The CRI
technology is a tertiary N2O removal technology for installation in
the tail gas stream of the nitric acid process after the absorber,
so unlike secondary technologies, there is no effect on plant
operation or nitric acid production. The CRI N2O technology can be
installed in either the high pressure position upstream of the
expander or in the low pressure position downstream of the
expander. Both options benefit from the low pressure drop of the
CRI N2O abatement system.
High
Pressure
Option
Low
Pressure Option
N2O
Decomposition: Caprolactam Plants
Certain
processes for the manufacture of caprolactam can have high N2O
emissions. The CRI N2O abatement technology is
highly effective in reducing N2O emissions from caprolactam
plants.
The CRI N2O
decomposition catalyst is stable in the presence of the trace
quantities of sulfur oxide (SOx) sometimes present in caprolactam
process tail gas.
A detailed
technical description of the technology can be found under Nitric
Acid Applications.
去除氧化亚氮系统(SDNS) 先进环保工艺：
氧化亚氮（N2O）硝酸厂及其它相关行业产生的温室气体。壳牌的氧化亚氮减排系统（SDNS)是先进的环保工艺，能去除烟气内95%以上的氧化亚氮；是属三级减排技术，布置在尾气端；其工艺处理是放热反应，节省能源，不需要添加任何反应剂的或添加剂；并具有体积小安装方便。
安装位置：
硝酸厂安装SDNS系统，可选择在高压装置（位于膨胀器前），或低压装置（位于膨胀器后）。
无论在什么位置，SDNS系统均能保持极小的压力降，对生产的影响极小。
SDNS系统适用于新建或改建的硝酸厂，并可根据客户的要求设计个别的方案和定制系统。
系统工作条件：
典型温度：475～525℃
压力：1～12 bar
