U.S. patent application number 14/351830 was filed with the patent office on 2015-06-11 for method and composition for detackifying organic contaminants in the process of pulping and papermaking.
This patent application is currently assigned to ECOLAB USA INC.. The applicant listed for this patent is ECOLAB USA INC.. Invention is credited to Zhi Chen, Quan Dong, Jian K. Shen, Qing Qing Yuan.
Application Number | 20150159328 14/351830 |
Document ID | / |
Family ID | 49624248 |
Filed Date | 2015-06-11 |
United States Patent
Application |
20150159328 |
Kind Code |
A1 |
Yuan; Qing Qing ; et
al. |
June 11, 2015 |
METHOD AND COMPOSITION FOR DETACKIFYING ORGANIC CONTAMINANTS IN THE
PROCESS OF PULPING AND PAPERMAKING
Abstract
The present invention discloses a method for detackifying
organic contaminants in the process of pulping and papermaking and
a composition used for the same. Specifically, the invention
discloses that the water circulation system of pulping and
papermaking process can be provided with non-ionic cellulose ether
and cationic coagulant in lower amount, through which, the de
position of organic contaminants can be inhibited under the
synergistic action of pre-coagulation and detackification.
Inventors: |
Yuan; Qing Qing; (Shanghai,
CN) ; Shen; Jian K.; (Shanghai, CN) ; Dong;
Quan; (Shanghai, CN) ; Chen; Zhi; (Shanghai,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ECOLAB USA INC. |
St. Paul |
MN |
US |
|
|
Assignee: |
ECOLAB USA INC.
St. Paul
MN
|
Family ID: |
49624248 |
Appl. No.: |
14/351830 |
Filed: |
May 9, 2013 |
PCT Filed: |
May 9, 2013 |
PCT NO: |
PCT/US2013/040388 |
371 Date: |
April 14, 2014 |
Current U.S.
Class: |
162/74 ;
162/72 |
Current CPC
Class: |
D21H 17/00 20130101;
D21H 17/26 20130101; D21C 9/08 20130101; D21H 17/25 20130101; D21H
21/02 20130101; D21H 17/41 20130101; D21H 17/74 20130101; D21H
17/29 20130101; D21H 17/45 20130101; D21H 17/56 20130101; D21H
17/66 20130101 |
International
Class: |
D21H 17/00 20060101
D21H017/00; D21H 17/29 20060101 D21H017/29; D21H 17/56 20060101
D21H017/56; D21H 17/26 20060101 D21H017/26 |
Foreign Application Data
Date |
Code |
Application Number |
May 21, 2012 |
CN |
201210159396.5 |
Claims
1. A method for detackifying organic contaminants in the process of
pulping and papermaking comprising adding an effective dose of
non-ionic cellulose ether and cationic coagulant into a papermaking
pulp.
2. The method according to claim 1, characterized in that the
non-ionic cellulose ether is selected from the group consisting of
hydroxyethyl methyl cellulose, hydroxyethyl cellulose,
hydroxypropyl methyl cellulose, hydroxypropyl cellulose,
hydroxybutyl methyl cellulose, hydroxybutyl cellulose and their
combination.
3. The method according to claim 1, characterized in that molecular
weight of the non-ionic cellulose ether is in the range from 10,000
to 1,000,000, and molar degree of substitution of the non-ionic
cellulose ether is in the range from 0.01 to 3.0.
4. The method according to claim 1, wherein the molecular weight of
the non-ionic cellulose ether is in the range from 50,000 to
500,000, and molar degree of substitution of the non-ionic
cellulose ether is in the range from 0.5 to 2.8.
5. The method according to claim 1, wherein the molecular weight of
the non-ionic cellulose ether is in the range from 80,000 to
250,000, and molar degree of substitution of the non-ionic
cellulose ether is in the range from 1.5 to 2.5.
6. The method according to claim 1, wherein the cationic coagulant
is an inorganic coagulant chosen from aluminum sulfate, aluminum
chloride, ferric sulfate, ferric chloride, polyaluminum sulfate,
polyaluminum chloride, aluminum chlorohydrate, polyaluminum sulfate
chloride, polyaluminum silicate chloride, polyferric chloride,
polyferric sulfate, polyferric sulfate chloride, polyferric
silicate chloride, and their combination.
7. The method according to claim 1, wherein the cationic coagulant
is an organic cationic coagulant chosen from linear or crosslinked
copolymer of epihalohydrin and aliphatic amine, poly (diallyl
dimethyl ammonium chloride), copolymer and terpolymer containing
cationic monomer of tertiary amino carboxylate, diallyl dimethyl
ammonium chloride or vinylamine, melamine-formaldehyde resin,
cationic starch, chitosan, cationic guar gum, and their
combination.
8. The method according to claim 1, wherein the proportion by
weight of non-ionic cellulose ether to cationic coagulant in the
composition is 1:0.1-1:100.
9. The method according to claim 8, wherein the proportion by
weight of non-ionic cellulose ether to cationic coagulant in the
composition is 1:0.5-1:20.
10. The method according to claim 9, wherein the proportion by
weight of non-ionic cellulose ether to cationic coagulant in the
composition is 1:1-1:10.
11. The method according to claim 1, wherein the pulp comprises
recycled pulp, coated broke, deinked pulp, mechanical pulp,
high-yield pulp, or the combination thereof.
12. The method according to claim 1, wherein the organic
contaminants are pitch and/or stickies produced in the process of
pulping and papermaking.
13. A composition used for detackifying organic contaminants in the
process of pulping or papermaking comprising non-ionic cellulose
ether and cationic coagulant.
14. The composition according to claim 13, wherein the non-ionic
cellulose ether is chosen from hydroxyethyl methyl cellulose,
hydroxyethyl cellulose, hydroxypropyl methyl cellulose,
hydroxypropyl cellulose, hydroxybutyl methyl cellulose,
hydroxybutyl cellulose and their combination.
15. The composition according to claim 13 wherein the molecular
weight of the non-ionic cellulose ether is in the range from 10,000
to 1,000,000, and molar degree of substitution of the non-ionic
cellulose ether is in the range from 0.01 to 3.0.
16. The composition according to claim 13, wherein the cationic
coagulant is an inorganic coagulant chosen from aluminum sulfate,
aluminum chloride, ferric sulfate, ferric chloride, polyaluminum
sulfate, polyaluminum chloride, aluminum chlorohydrate,
polyaluminum sulfate chloride, polyaluminum silicate chloride,
polyferric chloride, polyferric sulfate, polyferric sulfate
chloride, polyferric silicate chloride, and their combination.
17. The composition according to claim 13, wherein the cationic
coagulant is an organic cationic coagulant chosen from linear or
crosslinked copolymer of epihalohydrin and aliphatic amine, poly
(diallyl dimethyl ammonium chloride), copolymer and terpolymer
containing cationic monomer of tertiary amino carboxylate, diallyl
dimethyl ammonium chloride or vinylamine, melamine-formaldehyde
resin, cationic starch, chitosan, cationic guar gum, and their
combination.
18. The composition according to claim 13, wherein the proportion
by weight of non-ionic cellulose ether to cationic coagulant in the
composition is 1:0.1-1:100.
19. The composition according to claim 18, wherein the proportion
by weight of non-ionic cellulose ether to cationic coagulant in the
composition is 1:0.5-1:20.
20. The composition according to claim 19, wherein the proportion
by weight of non-ionic cellulose ether to cationic coagulant in the
composition is 1:1-1:10.
Description
TECHNICAL FIELD
[0001] The present invention relates to the pulping and papermaking
industry, and especially, to a chemical processing method for
detackifying organic contaminants in the process of pulping and
papermaking and a composition used for the same.
BACKGROUND
[0002] The term organic contaminants in papermaking process refers
to the interfering substances that have permanent or temporary
physical tackiness and may influence runnability of paper machines
and harm the quality of the paper or board product. The organic
contaminants can be divided into two types depending on their
sources, that is, pitch and stickies. Pitch refers to hydrophobic
colloidal particles, including those released from woods, such as
resin acids, fatty acids, triglycerides and unsaponifiable like
sterol esters and waxes, and those introduced into the pulping
process such as defoamers, rosin size, coatings, some components of
alkaline sizing agents, etc. The stickies refer to adhesive
materials derived from recycled fibers. The mixtures generally
comprise pressure-sensitive adhesives, hot-melt adhesives, latex
binders from coatings, ink adhesives, wet-strength resins, paraffin
waxes, and other polymers.
[0003] When conditions of the paper machine system (for example,
pH, temperature, water hardness, or shearing force of the system)
suddenly change, the two types of tacky organic contaminants are
apt to aggregate and deposit in the fabrics, felts, rolls, machine
wires, belts, presses, and dryer surfaces of the paper machine
system. As a result, the frequency of wash-ups, boil-outs, and
paper breaks on the machine increase. Moreover, when formed
deposits appear on final products in the form of paper defects such
as pinholes, spots, specks, and others, paper quality will
definitely be degraded and operational problems relating to the
subsequent coating or printing processes will also occur.
[0004] Currently, with the rising use of recycled paper and
high-yield mechanical pulp as raw materials, the increasing reuse
of paper machine white water, and the increasing content of
contaminants in recycled fiber, problems caused by pitch and
stickies are increasing.
[0005] In the pulping and papermaking industry, chemical processing
methods are generally used to inhibit or control the deposition of
organic contaminants, thus solving the aforementioned problems.
There are three chemical treatments that are commonly applied in
paper mills: detackification, dispersion, and fixation.
[0006] The chemical compositions of organic contaminants produced
in the process of pulping and papermaking may not be that similar,
but, they have the common physical properties of low melting
temperature/glass transition temperature and low surface energy
(high hydrophobicity). This means that they are apt to agglomerate
into larger particles when in water and adhere to interfaces of
metal, plastics and other synthetic materials in the papermaking
system to form deposits.
[0007] Inorganic passivators, including talc, bentonite, alum and
others, were previously used widely as detackifiers in pulping and
papermaking processes. Despite the advantage of low cost, they are
usually used in a large amount, and the huge variance of their
dispersity in water has limited their detackifying effectiveness in
practice.
[0008] Now, detackifiers that are commonly used include mainly
polymers of high hydrophilicity, for example, synthetic products of
polyvinyl alcohol-vinyl acetate (U.S. Pat. Nos. 4,871,424 and
4,886,575), polyethylene glycol and modified polyethylene glycol
(U.S. Patent Application No. 2008/0029231), polyethylene oxide and
modified polyethylene oxide (European patent application No.
1993/0568229), polyacrylate-styrene (U.S. Patent Application Nos.
2002/0148576 and 2003/0150578), etc. Detackifiers commonly used
also include natural products such as non-ionic cellulose ether
(U.S. Pat. Nos. 4,698,133 and 5,074,961), serum albumin and
globulin (U.S. Pat. No. 5,885,419).
[0009] For the detackifiers disclosed in the aforementioned
references to play the function of effectively inhibiting organic
deposits, they must be efficiently and selectively adsorbed to the
hydrophobic surface of particles in a physical or chemical manner,
and then these particles can be stably dispersed in water systems
due to their increased surface energy. However, sources of pulp
materials and application of chemical additives in paper mills vary
enormously. This means that deposits like pitch and stickies have
particular and complex categories and different consistencies as
well. Therefore, detackifiers containing a single component cannot
effectively solve the issues of deposition of organic
contaminants.
[0010] U.S. Pat. No. 5,540,814 discloses a method of using modified
cationic kaolin to remove stickies in wastepaper. This method can
effectively reduce the number of stickies and dirt in finished pulp
or paper products through sufficient surface cationization of an
anionic kaolin with epichlorohydrin dimethylamine polymer or poly
diallyl dimethyl ammonium halide. In addition, it can also
facilitate the removal of ink by centrifugal cleaners.
[0011] U.S. Pat. No. 6,977,027 discloses a process to control
stickies formation and remove anionic trashes from recycled old
corrugated container furnish, old newsprint furnish, deinking pulp
furnish, old magazine grade furnish, etc. by adding talc and
tertiary or quaternary amine through the means of blending. Through
this method, the forming of stickies can be effectively inhibited,
and the amount of anionic trashes in the recycled fibers can be
reduced.
[0012] U.S. Pat. Nos. 5,292,403 and 5,556,510 disclose a method of
using a composite detackifier comprising a charged polymer and an
oppositely charged surfactant to inhibit the deposition of organic
contaminants in a pulping and papermaking system. The former (U.S.
Pat. No. 5,292,403) applies carboxymethyl cellulose,
carboxymethylated starch or polyacrylic acid, etc. as the anionic
polymer, and for example, aliphatic amine or alkyl imidazoline,
etc. as the cationic surfactant; while the latter (U.S. Pat. No.
5,556,510) applies cationic starch as cationic polymer and, for
example, sodium soap of tall oil fatty acid as the anionic
surfactant. Both of these detackifiers are highly surface active
which may reduce the tackiness of pitch and stickies, thus
preventing the deposition of such contaminants on deposition prone
surfaces of the paper machine.
[0013] U.S. Pat. No. 5,723,021 discloses a method for inhibiting
deposition of contaminants in a pulping and papermaking system.
Specifically, the composite detackifier hereinto consists of three
components: a polyvinyl alcohol having 50-100% hydrolysis, a high
molecular weight gelatin protein, and a cationic polymer
represented by polyamine or polyethyleneimine. As revealed from the
results of examples, the above said tri-component detackifier has
such advantages as high efficiency, good adaptability and good
performance over a broad range of pH and water hardness.
Additionally, there is no obvious negative impact on wet end
retention and sizing.
[0014] U.S. Pat. No. 6,051,160 discloses a composition of
detackifier consisting of a derivatized cationic guar and a
styrene-maleic anhydride copolymer. This composition can be used as
a pitch control agent in the process of pulping and papermaking,
and it can also be used for the ionic balance of the papermaking
system to some extent.
[0015] U.S. Pat. No. 6,461,477 discloses a method for inhibiting
the deposition of organic contaminants in pulping and papermaking
system. Specifically, this method is to add a structured protein
(e.g., whey protein) and at least one of cationic polymer (e.g.,
poly (diallyldimethylammonium chloride), cationic starch, cationic
cellulose derivatives, alum, etc.) into the pulp, or apply them to
the deposition prone surfaces of papermaking machinery and
equipment, so as to minimize the deposition of pitch and
stickies.
[0016] U.S. patent application No. 2008/0169073 discloses a method
for inhibiting the deposition of organic contaminants in pulping
and papermaking system. Specifically, In this method, a combination
of a lipase and a non-ionic polymeric detackifier (e.g.,
hydrophobically modified hydroxyethyl methyl cellulose, and/or
polyvinyl acetate having 50-100% hydrolysis) are added into the
pulp, or applied to the deposition prone process equipment
surfaces, so as to minimize the deposition of pitch and stickies in
papermaking mills who use virgin pulp, recycled pulp or the
combinations.
[0017] U.S. Pat. No. 7,166,192 discloses a method of adding the
combination of hydrophobically modified hydroxyethyl methyl
cellulose and cationic polymers to control pitch and stickies. It
can be seen from the results of turbidity and UV-Vis absorption
spectra disclosed from the examples that, this method is mainly to
help improving the role of the cationic polymer in retaining pitch
and stickies on the paper fibers, by using hydrophobically modified
hydroxyethyl cellulose ether, so as to realize the purpose of
reducing the total deposits and optimizing the amount of
papermaking retention aids. Obviously, this method is neither to
disperse the pitch and stickies in the water system, nor to
detackify them, but to fix them onto paper fibers, and then remove
them from the paper machine system by retaining them in the
finished paper.
[0018] To conclude, the aforementioned prior art disclosed methods
for detackifying or re-dispersing or fixing the organic
contaminants onto the paper fibers, in the process of pulping and
papermaking through adding some substance or composition, so as to
control or inhibit the deposition of the organic contaminants,
namely, the pitch and stickies.
DESCRIPTION OF THE INVENTION
[0019] The purpose of the invention is to provide a detackifying
treatment for organic contaminants to inhibit and control the
deposition of organic contaminants in the process of pulping and
papermaking. By adopting the method according to the invention,
good detackifying results can be realized by very low amount of
composite detackifier, so that the deposition of organic
contaminants can be inhibited or controlled effectively. Wherein,
in the field of the invention, detackifying treatment is to make
organic contaminants absorb a water hydration layer by means of
surface passivation to improve its surface energy and
hydrophilicity, in order to achieve the purpose of reducing the
deposition of the organic contaminants.
[0020] For this purpose, the invention discloses a method for
detackifying organic contaminants in the process of pulping and
papermaking, comprising adding an effective dose of non-ionic
cellulose ether and cationic coagulant into water circulation
system of pulping and papermaking process.
[0021] The invention further discloses a composition used for
detackifying organic contaminants in the process of pulping and
papermaking, comprising non-ionic cellulose ether and cationic
coagulant.
[0022] The method and detackifying composition of the invention
realize good detackification of organic contaminants though the
synergistic effect of non-ionic cellulose ether and cationic
coagulant. Cationic coagulant catches colloidal and/or micro-sized
pitch and stickies etc. to form particle aggregates with the
controllable size of generally less than 100-150 micrometers by
means of pre-coagulation; while hydrophilic non-ionic cellulose
ether may be adsorbed onto the surfaces of these pre-coagulated
aggregates by physical means, so as to make them better dispersed
into the water system due to improved hydration, rather than
deposited in the system of pulping and papermaking or retention to
the surface of paper fibers.
[0023] After a plurality of experiments, the inventors find that
aforementioned synergistic action, comparing with the prior art of
detackification technology, significantly enhances the
absorbability of non-ionic cellulose ether to organic contaminants
to realize effective detackification of organic contaminants at
relatively lower dose of detackifier composition.
[0024] In the present invention, non-ionic cellulose ether may be
selected from hydroxyethyl methyl cellulose, hydroxyethyl
cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose,
hydroxybutyl methyl cellulose, hydroxybutyl cellulose or the
combination thereof. It is well known in prior art that the
above-listed non-ionic cellulose ethers have relatively good water
solubility and are cheap and easy to access.
[0025] In the presence of cationic coagulant, non-ionic cellulose
ether with high molecular weight has better fluidity, and
detackification capability of non-ionic cellulose ether has been
significantly improved. Therefore, comparing with prior art, the
method of the invention may have more broad selection of non-ionic
cellulose ethers. In actual production, various non-ionic cellulose
ethers and combinations thereof can be selected in response to the
requirement of operating parameter in the process.
[0026] In the present invention, for the reason that there is no
need for non-ionic cellulose ether to conduct special chemical
modification, the process can be more simple and easy, which leads
substantially same or similar result of organic contaminants
detackification.
[0027] As for molecular weight of non-ionic cellulose ether,
10,000-1,000,000 is preferred, more preferred 50,000-500,000, and
most preferred 80,000-250,000. Non-ionic cellulose ether in the
said molecular weight range will have an improved synergistic
effect with cationic coagulant.
[0028] A recommended molar degree of substitution of non-ionic
cellulose ether of 0.01-3.0, 0.5-2.8 is preferred, and 1.5-2.5 is
more preferred. In one embodiment of the invention, the molar
degree of substitution of methoxy group of non-ionic cellulose
ether may be 0-3.0, preferred 1.5-2.0; molar degree of substitution
of hydroxypropyl group may be 0.01-0.5, preferred 0.1-0.3.
Non-ionic cellulose ether with such range of degree of substitution
will have improved synergy effect with cationic coagulant.
[0029] In the present invention, the cationic coagulant may be
either inorganic coagulant or organic cationic coagulant. Wherein,
inorganic coagulant includes but is not limited to aluminum
sulfate, aluminum chloride, ferric sulfate, ferric chloride,
polyaluminum sulfate, polyaluminum chloride, aluminum
chlorohydrate, polyaluminum sulfate chloride, polyaluminum silicate
chloride, polyferric chloride, polyferric sulfate, polyferric
sulfate chloride, polyferric silicate chloride, and their
combination. Organic cationic coagulant includes but is not limited
to linear or crosslinked copolymers of epihalohydrin and aliphatic
amine, poly (diallyl dimethyl ammonium chloride), copolymer and
terpolymer containing cationic monomer of tertiary amino
carboxylate, diallyl dimethyl ammonium chloride or vinylamine,
melamine-formaldehyde resin, cationic starch, chitosan, cationic
guar gum, and their combination.
[0030] In the present invention, the proportion of non-ionic
cellulose ether and cationic coagulant (by weight) in the
detackifier composition may be 1:0.1-1:100, more preferred
1:0.5-1:20, and most preferred 1:1-1:10. The proportion of
non-ionic cellulose ether and cationic coagulant (by weight) may be
varied in response to the source of pulp, the quantity and chemical
properties of organic contaminants, or operating parameters in the
process of pulping and papermaking.
[0031] In the present invention, the dosage of detackifier
composition is the effective dosage for organic contaminants
detackification, which is the understandable common content for
those skilled in the art. The dosage that can be varied in response
to tonnage of pulp to be treated and volume of water circulation
system, is commonly 0.05-20 kilograms per ton of dry pulp base. Due
to the synergy effect of non-ionic cellulose ether and cationic
coagulant in the present invention, the dosage of the detackifier
composition in the present invention which is preferred 0.1-5
kilograms per ton of dry pulp base, more preferred 0.25-2.5
kilograms per ton of dry pulp base, can be lower than that of prior
art, based on same effect of detackification.
[0032] The detackifier composition of the present invention is
effective for treating all pulps, including but not limited to
recycled pulp, coated broke, deinked pulp, mechanical pulp,
high-yield pulp, or combinations thereof. Furthermore, the
detackifier composition of the present invention is effective for
treating white water.
[0033] Wherein, organic contaminants in the present invention means
interfering substances which have permanent or temporary physical
tackiness and may impact the runnability of the paper machine and
cause quality problems of paper, particularly means pitch and
stickies produced in the process of pulping and papermaking.
[0034] In the present invention, the composition comprising
non-ionic cellulose ether and cationic coagulant may be added at
the same time at any stage of the process of pulping and
papermaking, or non-ionic cellulose ether and cationic coagulant
can be separately added at any stage. It is only necessary to
guarantee that the said non-ionic cellulose ether and the said
cationic coagulant would join together in pulp or in water
circulation system of paper machine.
[0035] In the present invention, the composition comprising
non-ionic cellulose ether and cationic coagulant may be added in
any form (such as liquid, powder, aqueous carrier, etc.) in the
process of pulping and papermaking.
[0036] In the present invention, the composition comprising
non-ionic cellulose ether and cationic coagulant may be added by
any means (such as injection, sprinkling, spraying, etc.) in the
process of pulping and papermaking.
[0037] Furthermore, after treated by the method of the present
invention, the organic contaminants, of which hydrophilicity is
improved, can be better dispersed in the water system to
effectively prevent the organic contaminants from precipitation and
deposition onto papermaking equipment. Finally, the solution, with
a plurality of organic contaminants dispersed, will be discharged
out of circulation system of paper machine in mode of waste water
discharge or in any other known mode.
[0038] Comparing with the prior art, the method for detackifying
organic contaminants in the process of pulping and papermaking and
composition used for the same disclosed by the present invention
has the following advantages:
[0039] First, by pre-coagulation assisted detackification
synergistic action of non-ionic cellulose ether and cationic
coagulant, the adsorption of non-ionic cellulose ether to pitch and
stickies has been enhanced to realize effective detackifying at
lower amount of detackifier, so that the purpose of inhibiting
deposits is achieved.
[0040] Second, there is no need to conduct any chemical
modification to non-ionic cellulose ether used in the present
invention. The process is simple and of low cost, which is easier
to be operated and realized.
[0041] Third, the detackification of method and composition
according to the present invention may not be affected by the pH
and hardness of papermaking plant water system; meanwhile, the
addition of cationic coagulant in the present invention can
additionally provide ionic balance for stickies, which is
particularly helpful for inhibiting and removing anionic trashes in
paper fiber.
[0042] Fourth, foaming control performance resulted by adding and
diluting detackifier composition is clearly greater than that of
surfactant-type pitch control dispersant in the process of pulping
and papermaking.
[0043] Fifth, the detackifier composition of the present invention
may be applicable together with most chemical additives such as wet
end retention, sizing, dry strength/wet strength additives etc.
There is no negative effect on the operation of paper machine by
the use of the composition itself and together with other chemical
additives.
PREFERRED EMBODIMENT
[0044] Standard pitch deposition test is used to evaluate the
deposition inhibition effect of the detackifier composition and the
method disclosed in the present invention on organic
contaminant:
[0045] Standard pulp sample with 1.4% pulp consistency and Canadian
standard freeness in the range of 450-500 mL at 20.degree. C. is
prepared using dry pulp laps in deionized water by Valley Beater. A
synthetic pitch solution in isopropanol (i.e., 1 wt. %, 100 mL),
and a calcium chloride solution (i.e., 5000 ppm as calcium ions, 5
mL) were added into 1 L standard pulp sample sequentially.
Synthetic contaminants to be tested, of which both composition and
proportion consistent with the those of wood pitch in hardwood and
softwood (see the following table), is dispersed uniformly in the
standard pulp sample in the form of colloids by gentle stirring.
The only difference is that the pitch content in standard pulp
sample used in test is much higher than actual content. Standard
pulp sample is heated to 50.degree. C. Stirring is continued for
1.5 hour at a constant stirring rate while the temperature is
maintained. Meanwhile, the technique of quartz crystal microbalance
(QCM) was applied to monitor the accumulated deposit mass on quartz
crystal. The performance of the detackifier composition is also
tested, wherein, after pulp sample to be tested is heated to
50.degree. C., a certain dosage of composition is added for
pre-treatment, then QCM test is conducted. Other preparation steps
are the same.
TABLE-US-00001 Table of Synthetic Pitch Compositions Abietic acid
5-50% Oleic acid 10-25% Palmitic acid 5-10% Corn oil 10-35% Oleyl
alcohol 2.5-7.5% Methyl stearate 5-15% Beta-sitosterol 2.5-7.5%
Cholesteryl caproate 2.5-7.5%
Example 1
[0046] Hydroxyethyl cellulose (HEC) aqueous solution (8 wt. %) and
epichlorohydrin-dimethylamine cross-linked copolymer (Epi-DMA)
water solution (50 wt. %) is mixed with different combination
proportion (proportion of 80/20, 60/40, 40/60 and 20/80 by weight);
meanwhile, the detackification of organic contaminant for each
composition is assessed by standard pitch deposition test. It can
be seen from Table-1 that the compositions with certain proportion
can detackify organic contaminants more effectively than either
hydroxyethyl cellulose or organic cationic coagulant.
[0047] Wherein, blank test is a test during which any detackifier
is not added.
TABLE-US-00002 TABLE 1 Pitch Deposition Test Results of
Hydroxyethyl Cellulose/Organic Cationic Coagulant Compositions
Weight of accumulated Dosage pitch deposits Detackification (ppm)
(mg) (%) Blank test -- 93.0 0 HEC (8 wt % aq. solution) 10 33.4
61.4 Epi-DMA (50 wt % aq. 10 13.7 85.3 solution) HEC (8 wt
%)/Epi-DMA 10 24.3 73.9 (50 wt %) composition-80/20 HEC (8 wt
%)/Epi-DMA 10 15.6 83.2 (50 wt %) composition-60/40 HEC (8 wt
%)/Epi-DMA 10 8.9 90.4 (50 wt %) composition-40/60 HEC (8 wt
%)/Epi-DMA 10 9.7 89.6 (50 wt %) composition-20/80 HEC (8 wt % aq.
solution) 25 21.6 76.8 Epi-DMA (50 wt % aq. 25 7.4 92.0 solution)
HEC (8 wt %)/Epi-DMA 25 7.4 92.0 (50 wt %) composition-80/20 HEC (8
wt %)/Epi-DMA 25 4.3 95.4 (50 wt %) composition-60/40 HEC (8 wt
%)/Epi-DMA 25 2.6 97.2 (50 wt %) composition-40/60 HEC (8 wt
%)/Epi-DMA 25 6.1 93.4 (50 wt %) composition-20/80
Example 2
[0048] Hydroxypropyl cellulose (HPC) aqueous solution (4 wt. %) and
cationic starch (CS) aqueous solution (22 wt. %) is mixed with
different combination proportion (proportion of 80/20, 60/40, 40/60
and 20/80 by weight); meanwhile, the detackification of organic
contaminants for each composition is assessed by standard pitch
deposition test. It can be seen from Table-2 that the compositions
with certain proportion can detackify organic contaminants more
effectively than either hydroxylpropyl cellulose or organic
cationic coagulant.
TABLE-US-00003 TABLE 2 Pitch Deposition Test Results of
Hydroxypropyl Cellulose/Organic Cationic Coagulant Compositions
Weight of accumulated Dosage pitch deposits Detackification (ppm)
(mg) (%) Blank test -- 59.6 0 HPC (4 wt % aq. solution) 10 48.4
18.8 CS (22 wt % aq. solution) 10 12.8 78.5 HPC (4 wt %)/CS (22 wt
%) 10 29.8 50.0 composition-80/20 HPC (4 wt %)/CS (22 wt %) 10 7.5
87.4 composition-60/40 HPC (4 wt %)/CS (22 wt %) 10 4.9 91.8
composition-40/60 HPC (4 wt %)/CS (22 wt %) 10 5.8 90.3
composition-20/80 HPC (4 wt % aq. solution) 25 32.9 44.8 CS (22 wt
% aq. solution) 25 4.1 93.1 HPC (4 wt %)/CS (22 wt %) 25 7.9 86.7
composition-80/20 HPC (4 wt %)/CS (22 wt %) 25 5.1 91.4
composition-60/40 HPC (4 wt %)/CS (22 wt %) 25 2.9 95.1
composition-40/60 HPC (4 wt %)/CS (22 wt %) 25 4.1 93.1
composition-20/80
Example 3
[0049] Hydroxypropyl methyl cellulose (HPMC) aqueous solution (5
wt. %) and polyaluminum chloride (PAC) aqueous solution (50 wt. %)
is mixed with different combination proportion (proportion of
80/20, 60/40, 40/60 and 20/80 by weight); meanwhile, the
detackification of organic contaminants for each composition is
assessed by standard pitch deposition test. It can be seen from
Table-3 that the compositions with certain proportion can detackify
organic contaminants more effectively than either hydroxypropyl
methyl cellulose or inorganic coagulant.
TABLE-US-00004 TABLE 3 Pitch Deposition Test Results of
Hydroxypropyl Methyl Cellulose/Inorganic Compositions Weight of
accumulated Dosage pitch deposits Detackification (ppm) (mg) (%)
Blank test -- 77.1 0 HPMC (5 wt % aq. solution) 10 24.3 68.5 PAC
(50 wt % aq. solution) 10 31.7 58.9 HPMC (5 wt %)/PAC (50 10 9.5
87.7 wt %) composition-80/20 HPMC (5 wt %)/PAC (50 10 5.6 92.7 wt
%) composition-60/40 HPMC (5 wt %)/PAC (50 10 8.5 89.0 wt %)
composition-40/60 HPMC (5 wt %)/PAC (50 10 12.3 84.0 wt %)
composition-20/80 HPMC (5 wt % aq. solution) 25 13.4 82.6 PAC (50
wt % aq. solution) 25 15.8 79.5 HPMC (5 wt %)/PAC (50 25 5.6 92.7
wt %) composition-80/20 HPMC (5 wt %)/PAC (50 25 2.9 96.2 wt %)
composition-60/40 HPMC (5 wt %)/PAC (50 25 4.5 94.2 wt %)
composition-40/60 HPMC (5 wt %)/PAC (50 25 8 89.6 wt %)
composition-20/80
[0050] The data from the Table 1-3 also indicate that low-dose of
the detackifier composition of the present invention can
effectively reduce tackiness of organic contaminants, so as to
reduce deposition of organic contaminants effectively.
[0051] Purpose of the above embodiments is to further illuminate
and describe technique scheme of the invention, rather than
limiting the scope of protection of the invention. According to the
content disclosed in the present invention, those skilled in the
art may also conduct any modification and improvement, including
proportion adjustment of non-ionic cellulose ether and cationic
coagulant, selection of any non-ionic cellulose ether and cationic
coagulant. Such modification and improvement are not go beyond the
scope of protection.
* * * * *