CO2 Recovery Technology
There are wide sources of CO2. Mainly sources: CO2 gas field, oil
refinery plant hydrogen generation process in oil refinery plant,
chemical fertilizer plant; mine ore decomposition; mine gas in the
mine well, fermentation process etc.
According to different CO2 sources and different customer
requirements, the recovery methods are also different. It can be
generalized in five methods:
Solvent absorption method; pressure differential absorption method;
organic membrane separation, absorption distillation method; and
catalysis burning method.
Section A. CO2 Recovery Process
Based on CO2 gas concentration, Jiangsu Kaimao Chemical Technology
Co., Ltd. has two recovery technology: Solvent absorption method
(Chemical absorption method) and absorption distillation method.
1.Chemical absorption method
Chemical absorption method is mainly applied in about 25％CO2
concentration flue gas. Use chemical solvents to absorb CO2 in the
flue gas at low temperature; when the solution is heated, CO2 will
be stripped from the chemical solvents and high concentration CO2
is received, while the solvents can be circulated for re-use.
Chemical absorption method features:
1)The CO2 chemical absorption solvents developed by Jiangsu Kaimao
(patent applied) has higher absorption rate than common absorption
solvents with quick stripping under low stripping temperature,
therefore, reduce absorption solvents consumption, decrease energy
consumption with high stability, no degrading and save operation
costs. Our new type solvent facility investment is 1/3 lower than
MEA solvent facility.
2)Set effluent gas pretreatment system, sulfides, dust, water and
impurities will be removed in scrubber at one time. The newly
developed SO2 absorption solution ( Patent applied) by Kaimao Co.
can only absorb SO2 gas, not CO2, thus, the CO2 recovery yield will
be increase greatly.
3)CO2 collecting process uses heat exchanger, CO2 cooler several
stages heat exchanging facilities to achieve comprehensive use of
heat. The system has low energy consumption.
4)Use effluent gas scrubbing, gas/liquid separation etc. system to
sufficiently recover the special absorption solution in the
effluent gas and maintain water balance for the whole collecting
system with low consumption of absorption solution and water.
2.Absorption distillation method
The CO2 recovery and refining technology developed by Kaimao Co. by
using absorption distillation method is applied for recovering high
concentration (CO2 more than 90％) CO2 gas to meet Chinese food
grade and industrial grade standard.
Technical features of absorption distillation method
1)Different recipes and performance of absorption solution is
applied for removing sulfides, nitrogen, oxygen compounds, grease,
and oxygen contained organic chemicals, hydrocarbons, benzene
series chemicals, nitrogen, phosphoric cyanides and water, based on
different impurities in the high concentration carbon dioxide, so
that to meet Chinese food grade standard requirement.
2)Use scientific method to select several different function
absorption agents filling on the absorption or drying bed to absorb
different compositions, as a result, to achieve simple flow process
and operation costs reduction.
3)Directly use the light fraction gas discharged from the top of
distillation tower and flashing distillation tank as the
regeneration gas for the absorption and drying bed. In this way, no
need to use high temperature steam or high purity nitrogen gas,
greatly reduce operation costs.
4)Based on the light fraction compositions properties, which
contains hydrogen, oxygen, nitrogen, argon and methane gas, select
advanced and complicated SH-BWR non-ideal materials system module
to calculate and obtain accurate distillation tower design
parameters, also use heat pump distillation technology to assure
all the light fraction compositions to be removed to ppm grade.
5)Through scientific comparison and optimized design, the process
uses low and middle pressure CO2 liquefaction purification
technology, which can simplify process, save investment, reduce
costs and still produce high purity CO2 product.
6)The whole process uses absorption and distillation combination
method to achieve simple process, easy operation. and can produce
industrial grade product. Food grade product is also able to be
produced through proper innovation. It has flexible process and
strong market adaptability.
7)High automation, main specification index are automatically
monitored and adjusted, no need operator work on the site.
Section B. CO2 Applications
CO2 has wide sources, also has wide applications. Mainly as
1.Machinery Industry: CO2 gas protection welding is the key