The mode of cycle economy utilization in stalk
──the technique system of clean pulp
production by the co-production of pulp and
organic fertilizer
Zhang Xiaoyong
Institute of Process Engineering
Chinese Academy of Sciences
Outlines
1.
Situation and problems in the fields of fertilizer and
paper-making in China
2. Academic idea to solve the problems
3. Strategy
4. Key techniques
5. Total aim
6. Practice
1.Situation and problems in the fields of fertilizer
and paper-making in China
The situation of fertilizer
‰ Chinese production and consumption of Chemical
fertilizer occupy the first place in the world the total
amount of which are about 50 million tons
‰ Chemical fertilizer is dominate and organic fertilizer
is very few.
Chemical fertilizer is 90%, Organic fertilizer is only
10%
‰ The production scale of organic fertilizer is very
small
The problems of the fertilizer
‰ Utilization rate of fertilizer is low
N≦35%
P ≦ 25% K ≦ 40%
‰ Environmental pollution is serious, The soil is
changed to be harden。
‰ The quality of agriculture product has been reduced,
in addition,the plant diseases and insect pests have
been increased
The situation of paper-making
‰ Chinese consumption of paper products occupy the
second place in the world, the total amount of which
are about 40 million tons
but one person consumption is very low
‰ (55kg/one person in the world,30kg/one person in
China)
‰ The primary material used to make paper is
stalk(80%)
China lack foresty
Problems of paper-making
‰ Black liquor of pulp cause the river to be pollution
badly.
Pulp-making is one of the most serious pollution
industry in China
‰ The development of pulp making industry is greatly
reduced.
A large part of pulp depend on import which is
2000tons/year.
2. Academic idea to solve the problems
‰ Utilization of waste as resource
‰ Combination of multi-subjects knowledge
‰ System integration and process optimization
‰ Set up the mode of cycle economy
3. Strategy
We make up organic fertilizer by pulp black
liquor, it is can eliminate the pollution
thoroughly and also provide a great deal
organic fertilizer, change the structure of
fertilizer effectively, it is possible to set
up a new industry with the good combination
between pulp making and fertilizer making。
Treatment Technique of black liquor in
abroad –alkali recovery
Black liquor
cooking
evaporation
Alkali solution
condense solution
combustion
basification
ash
calcareousness
alkali recovery technique is suitable to be used to treat black liquor
from wood pulp, but it is unsuitable to be used in treatment of black
liquor from stalk pulp, because the wood pulp in abroad is dominate but
in China the stalk pulp making is dominate. Due to higher content of
silicon in the black liquor of stalk leading to lower efficiency of alkali
recovery.
alkali recovery technique is not suitable to the black liquor of stalk
pulp
Normal flow of stalk pulp making in China
effluent
pollutant
Na-alkali
cooking
Black liquor
Middle waste water
Aerate
treatment
stalk
Clean water
Paper making
pulp
wash
blanch
White pulp
The effluent of black liquor leading to serious
environment pollution
Paper
The black liquor of pulp is the best
material for making fertilizer
‰ The Content of organic material in the black liquor is high
‰ The active groups in the nature material is abundant which make fertilizer
have good slow-release characteristics.
‰ The size of organic molecules is smaller and it is unnecessary to be
fermented, which avoid to decompose in a long time as normal organic
fertilizer making.
‰ The amount of this organic material is enormous and it has been
concentrated in the plant,it is beneficial to produce organic fertilizer in a
large scale
The composition of the stalk black liquor
lignin 20%
Organic
65%
humic acid 33％
Organic nutriment
organic acid 12%
Soluble
material
Na-alkali 30％
Inorganic
35%
Hurtful to plant
SiO2 1％
Inorganic nutriment
salt 4％
Inorganic nutriment
4. Key techniques
‰ The novel cooking technique based on preparation of fertilizer
using black liquor
‰ Technique of fertilizer production with black liquor
‰ Lower cost production of cooking agent
‰ High efficient evaporation technique of black liquor
KCl
stalk
Waste
technique
product
hydrolyze
KOH
material
K-alkali
pulp
making
Waste water
Acid bacteria
Leftover
material
Flue gas
Black
liquor
De-S,N
lignin
Liquid
preparation
P-production
P-fertilizer
fertilizer
K-material
Biochemical
treatment
phosphorite
solidify
Acid method
K-solution
HCl
N-fertilizer
microbe
Slow-release
preapration
Active
mud
paper
Liquid
fertilizer
Lignin
fertilizer
Kfertilizer
Technique flow
Organic
fertilizer
Biological
fertilizer
5. Objective
to solve the problems of paper and fertilizer at the
same time, set up a clean production of associative
industry, utilize the stalk resource in high efficiency
6. Practice
we have set up a Pilot of clean and high value
utilization of cotton stalk at Xingjiang province in
this mode.
It has 10tons/day capacity of production
Status and characteristics in Xinjiang cotton area
‡Xinjiang is the biggest cotton plant area in
China, the cotton output is 33%.so the
cotton stalk is enormous(4 million tons/year)
‡ Xinjiang is also the biggest drip irrigation
area in the world,there is 8 million ha. so
the need of liquid fertilizer is
enormous( because the fertilizer follow the
water irrigation)
The cotton area of Xinjiang province has special
excellent condition
‰ Cotton stalk is abundant and the need of liquid fertilizer is
enormous
‰ The production cost of liquid fertilizer by the black liquor is
very low
‰ The black liquor can be consumed in time
‰ The clean production with cotton stalk can be realized
easily
The mode of cycle economic utilization in cotton stalk
cotton
Solid
fertilizer
K-puple
making
paper
Fertilizer
making
Cotton plant
stalk
product
Black liquor
Liquid
fertilizer
waste
system of drip
irrigation
Base fertilizer
superaddition fertilizer
Significance-setting up an new ecological
industry
If 50% of the cotton stalk is utilized in the
mode, it will bring 10 billions RMB GDP and 2
billions profit
An ecological industry
Achievement
‰ We have completed all the laboratory research
‰ We have acquired successful in the middle scale
production and set up a pilot.
‰ Quality of pulp and fertilizer reach the national
standard.
‰ We completed the field trial of the fertilizer, the
effect is satisfactory.
Thanks for your attention！