NZ726380A - Leather production using waste liquids - Google Patents
Leather production using waste liquidsInfo
- Publication number
- NZ726380A NZ726380A NZ726380A NZ72638016A NZ726380A NZ 726380 A NZ726380 A NZ 726380A NZ 726380 A NZ726380 A NZ 726380A NZ 72638016 A NZ72638016 A NZ 72638016A NZ 726380 A NZ726380 A NZ 726380A
- Authority
- NZ
- New Zealand
- Prior art keywords
- agent
- waste liquid
- drum
- tanning
- liming
- Prior art date
Links
- 239000002699 waste material Substances 0.000 title claims abstract description 100
- 239000007788 liquid Substances 0.000 title claims abstract description 96
- 239000010985 leather Substances 0.000 title claims abstract description 41
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 34
- 238000000034 method Methods 0.000 claims abstract description 61
- 238000002791 soaking Methods 0.000 claims abstract description 40
- 230000003472 neutralizing Effects 0.000 claims abstract description 23
- 238000004043 dyeing Methods 0.000 claims abstract description 21
- 238000005238 degreasing Methods 0.000 claims abstract description 20
- 238000005554 pickling Methods 0.000 claims abstract description 15
- 238000005406 washing Methods 0.000 claims abstract description 12
- 239000003795 chemical substances by application Substances 0.000 claims description 44
- BDAGIHXWWSANSR-UHFFFAOYSA-N formic acid Chemical compound OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 claims description 24
- 238000005237 degreasing agent Methods 0.000 claims description 22
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 21
- 235000015450 Tilia cordata Nutrition 0.000 claims description 21
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 21
- 239000004571 lime Substances 0.000 claims description 21
- 102000004190 Enzymes Human genes 0.000 claims description 17
- 108090000790 Enzymes Proteins 0.000 claims description 17
- 239000002425 soil liming agent Substances 0.000 claims description 17
- 239000011780 sodium chloride Substances 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 150000003839 salts Chemical class 0.000 claims description 13
- UIIMBOGNXHQVGW-UHFFFAOYSA-M NaHCO3 Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 10
- HLBBKKJFGFRGMU-UHFFFAOYSA-M Sodium formate Chemical compound [Na+].[O-]C=O HLBBKKJFGFRGMU-UHFFFAOYSA-M 0.000 claims description 9
- 239000004280 Sodium formate Substances 0.000 claims description 9
- GRVFOGOEDUUMBP-UHFFFAOYSA-N Sodium sulfide Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 claims description 9
- MUBZPKHOEPUJKR-UHFFFAOYSA-N oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims description 9
- 235000019254 sodium formate Nutrition 0.000 claims description 9
- 229910052979 sodium sulfide Inorganic materials 0.000 claims description 9
- 239000003513 alkali Substances 0.000 claims description 8
- VYZAMTAEIAYCRO-UHFFFAOYSA-N chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 8
- 235000019253 formic acid Nutrition 0.000 claims description 8
- 239000000843 powder Substances 0.000 claims description 8
- HYHCSLBZRBJJCH-UHFFFAOYSA-M Sodium hydrosulfide Chemical compound [Na+].[SH-] HYHCSLBZRBJJCH-UHFFFAOYSA-M 0.000 claims description 6
- -1 aliphatic aldehyde Chemical class 0.000 claims description 6
- 230000000844 anti-bacterial Effects 0.000 claims description 6
- 239000003899 bactericide agent Substances 0.000 claims description 6
- 239000002270 dispersing agent Substances 0.000 claims description 6
- 239000002253 acid Substances 0.000 claims description 5
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 5
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 5
- JLPULHDHAOZNQI-ZTIMHPMXSA-N 1-hexadecanoyl-2-(9Z,12Z-octadecadienoyl)-sn-glycero-3-phosphocholine Chemical compound CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCCCCCC\C=C/C\C=C/CCCCC JLPULHDHAOZNQI-ZTIMHPMXSA-N 0.000 claims description 4
- BFNBIHQBYMNNAN-UHFFFAOYSA-N Ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims description 4
- 229940067606 Lecithin Drugs 0.000 claims description 4
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims description 4
- 235000011130 ammonium sulphate Nutrition 0.000 claims description 4
- QGBSISYHAICWAH-UHFFFAOYSA-N cyanoguanidine Chemical compound NC(N)=NC#N QGBSISYHAICWAH-UHFFFAOYSA-N 0.000 claims description 4
- 239000000787 lecithin Substances 0.000 claims description 4
- 235000010445 lecithin Nutrition 0.000 claims description 4
- 239000010697 neat foot oil Substances 0.000 claims description 4
- 102000004169 proteins and genes Human genes 0.000 claims description 4
- 108090000623 proteins and genes Proteins 0.000 claims description 4
- 239000002610 basifying agent Substances 0.000 claims description 3
- 238000011049 filling Methods 0.000 claims description 3
- 230000000855 fungicidal Effects 0.000 claims description 3
- 239000000417 fungicide Substances 0.000 claims description 3
- 235000006408 oxalic acid Nutrition 0.000 claims description 3
- 239000004925 Acrylic resin Substances 0.000 claims description 2
- 229920000178 Acrylic resin Polymers 0.000 claims description 2
- 229940044197 Ammonium Sulfate Drugs 0.000 claims description 2
- 229940044172 CALCIUM FORMATE Drugs 0.000 claims description 2
- CBOCVOKPQGJKKJ-UHFFFAOYSA-L Calcium formate Chemical compound [Ca+2].[O-]C=O.[O-]C=O CBOCVOKPQGJKKJ-UHFFFAOYSA-L 0.000 claims description 2
- JDSHMPZPIAZGSV-UHFFFAOYSA-N Melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims description 2
- 229920000877 Melamine resin Polymers 0.000 claims description 2
- 239000004281 calcium formate Substances 0.000 claims description 2
- 235000019255 calcium formate Nutrition 0.000 claims description 2
- 125000002091 cationic group Chemical group 0.000 claims description 2
- 239000003431 cross linking reagent Substances 0.000 claims description 2
- 229960001407 sodium bicarbonate Drugs 0.000 claims description 2
- 235000013311 vegetables Nutrition 0.000 claims description 2
- 239000010808 liquid waste Substances 0.000 description 37
- 239000000126 substance Substances 0.000 description 24
- 210000004209 Hair Anatomy 0.000 description 7
- 239000000203 mixture Substances 0.000 description 7
- QTBSBXVTEAMEQO-UHFFFAOYSA-N acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 6
- 150000001413 amino acids Chemical class 0.000 description 6
- CDBYLPFSWZWCQE-UHFFFAOYSA-L sodium carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 6
- 239000011651 chromium Substances 0.000 description 5
- 210000003491 Skin Anatomy 0.000 description 4
- 229910052804 chromium Inorganic materials 0.000 description 4
- 239000000975 dye Substances 0.000 description 4
- 239000000945 filler Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- VXMKYRQZQXVKGB-CWWHNZPOSA-N Tannin Chemical compound O([C@H]1[C@H]([C@@H]2OC(=O)C3=CC(O)=C(O)C(O)=C3C3=C(O)C(O)=C(O)C=C3C(=O)O[C@H]([C@H]2O)O1)O)C(=O)C1=CC(O)=C(O)C(O)=C1 VXMKYRQZQXVKGB-CWWHNZPOSA-N 0.000 description 3
- 238000011109 contamination Methods 0.000 description 3
- 235000017550 sodium carbonate Nutrition 0.000 description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 description 3
- 150000004763 sulfides Chemical class 0.000 description 3
- 235000018553 tannin Nutrition 0.000 description 3
- 229920001864 tannin Polymers 0.000 description 3
- 239000001648 tannin Substances 0.000 description 3
- KQTHWILIRXZROE-UHFFFAOYSA-N CSC(OC)=S.[Na] Chemical compound CSC(OC)=S.[Na] KQTHWILIRXZROE-UHFFFAOYSA-N 0.000 description 2
- 102000008186 Collagen Human genes 0.000 description 2
- 108010035532 Collagen Proteins 0.000 description 2
- GCLGEJMYGQKIIW-UHFFFAOYSA-H Sodium hexametaphosphate Chemical compound [Na]OP1(=O)OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])OP(=O)(O[Na])O1 GCLGEJMYGQKIIW-UHFFFAOYSA-H 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000001887 acacia decurrens willd. var. dealbata absolute Substances 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid Chemical compound OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 238000005273 aeration Methods 0.000 description 2
- 150000001412 amines Chemical class 0.000 description 2
- 150000003863 ammonium salts Chemical class 0.000 description 2
- 239000004067 bulking agent Substances 0.000 description 2
- 229960005188 collagen Drugs 0.000 description 2
- 229920001436 collagen Polymers 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000004519 grease Substances 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N oxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 229920000137 polyphosphoric acid Polymers 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 235000019982 sodium hexametaphosphate Nutrition 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 description 2
- 241000157302 Bison bison athabascae Species 0.000 description 1
- 206010013786 Dry skin Diseases 0.000 description 1
- 102000011782 Keratins Human genes 0.000 description 1
- 108010076876 Keratins Proteins 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- 229940051875 Mucins Drugs 0.000 description 1
- 102000015728 Mucins Human genes 0.000 description 1
- 108010063954 Mucins Proteins 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N Sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 239000004902 Softening Agent Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- 238000010170 biological method Methods 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 1
- 230000037336 dry skin Effects 0.000 description 1
- 230000002349 favourable Effects 0.000 description 1
- 239000002440 industrial waste Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006011 modification reaction Methods 0.000 description 1
- 230000001264 neutralization Effects 0.000 description 1
- 150000002830 nitrogen compounds Chemical class 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000001187 sodium carbonate Substances 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
Abstract
process for leather production from a raw animal hide includes the steps of pre-soaking, soaking, unhairing and liming, re-liming, deliming and bating, pickling and tanning, degreasing, re-tanning, neutralizing, dyeing and fatliquoring, and washing the processed hide. Waste liquid is collected from at least one of the foregoing steps is recycled to at least one of the foregoing steps. The collected waste liquid can be recycled to the same step, to a different step, or to two of more steps in the process. m at least one of the foregoing steps is recycled to at least one of the foregoing steps. The collected waste liquid can be recycled to the same step, to a different step, or to two of more steps in the process.
Description
LEATHER PRODUCTION USING WASTE LIQUIDS
Cross-Reference to Related Application
This application is related to and claims priority benefits from Chinese
patent application No. 201510826825.3 filed on November 25, 2015, which is
hereby incorporated by reference in its entirety.
Field of the Invention
The present invention relates to the technical field of leather production
with waste liquids in the tanning industry.
Background of the Invention
During tanning production processes, large quantities of waste liquids
and waste solids are produced, which contain plentiful lime, salts, oil and grease,
ammonia and other nitrogen compounds, proteins, sulfides, chromates, dyes, hairs,
leather residues, silts, and other waste products. The wastes have very high
chemical oxygen demand (COD) and biochemical oxygen demand (BOD), high
variation coefficients and a stench. These industrial wastes are difficult to treat and
generate serious contamination to the environment.
As society is setting higher standards for environmental protection, how
to treat tanning waste liquids has become a difficult issue that must be addressed
by the industry. To solve this difficult problem, through many years of research
and development, and commercial applications, it has been found that the waste
liquids are actually valuable and can be reused since they contain a lot of beneficial
ingredients. Making leather with waste liquids can produce leather with quality
superior to those made from conventional processes that use fresh water. Enzymes
and decomposition products in the waste liquids are all beneficial for leather
production. For example, amino acids and saponified substances are beneficial for
filling collagen fibers and enable the waste liquids to maintain a stable state. The
present process takes advantage of the beneficial properties of waste liquids to
produce leather using waste liquids. The present process effectively solves
environmental protection issues for the tanning industry, and improves product
quality. This new process provides the tanning industry with both economic and
environmental benefits.
In the tanning industry, the terms “hide” and “skin” are oftentimes used
interchangeably, each referring to the integument or natural covering of an animal.
Since the term “hide” is most often associated with larger animals such as cows or
bison, the term “hide” will be used hereinafter. It should be understood, however,
that the process for the production of leather described and claimed herein can be
applied equivalently to animal skin as well as animal hide.
Summary of the Invention
A process for producing leather uses waste liquids that are repeatedly
employed to produce improved leather products. A waste liquid is employed in one
or more of the steps of the process. Combinations of waste liquids can be
employed in one or more of the steps of the process.
The present process for producing leather using waste liquids comprises
at least one of the following steps:
(1) A pre-soaking step in which liquid waste and chemicals ordinarily
added are used. Liquid waste is collected at the end of this step.
The pre-soaking step employs at least one of a soaking agent, a
bactericide, a degreasing agent, salt or an alkali.
(2) A soaking step in which liquid waste and chemicals ordinarily
added are used to restore dry skins to freshness and remove soluble
proteins and grease from raw skins. The soaking step employs at
least one of a soaking agent, an enzyme, a bactericide, a degreasing
agent, salt or an alkali. Liquid waste is collected at the end of this
step.
(3) An unhairing and liming step in which liquid waste and chemicals
ordinarily added are used to remove hairs from skins and filter out
the hairs. The unhairing and liming step employs at least one of a
liming agent, an enzyme, lime, a lime dispersant, sodium
hydrosulfide, sodium sulfide, a degreasing agent, salt or an alkali
to remove hair from the hide. Liquid waste is collected at the end
of this step.
(4) A re-liming step in which liquid waste and chemicals ordinarily
added are used. The re-liming step employs at least one of a liming
agent, an enzyme, lime, a lime dispersant, sodium hydrosulfide,
sodium sulfide, a degreasing agent or an alkali. Liquid waste
collected at the end of this step.
(5) A deliming and bating step in which liquid waste and chemicals
ordinarily added are used. The deliming and bating step employs at
least one of a deliming agent, an enzyme, a lime dispersant, a
degreasing agent, ammonium sulfate or an acid. Liquid waste is
collected at the end of this step.
(6) A pickling and tanning step in which liquid waste and chemicals
ordinarily added are used. The pickling and tanning step employs
at least one of a degreasing agent, salt, a fungicide, an acid, a
fatliquoring agent, a cross-linking agent, chrome powder, a
basifying agent or sodium formate. Liquid waste is collected at the
end of this step.
(7) A degreasing step in which liquid waste and chemicals ordinarily
added are used. The degreasing step employs at least one of a
degreasing agent, formic acid or oxalic acid. Liquid waste is
collected at the end of this step.
(8) A re-tanning process in which liquid waste and chemicals
ordinarily added are used. The re-tanning step employs at least one
of chrome powder, a tanning agent, a protein filling agent, an
aliphatic aldehyde or an acrylic resin tanning agent. Liquid waste
is collected at the end of this step.
(9) A neutralizing step in which liquid waste and chemicals ordinarily
added are used. The neutralizing step employs at least one of a
neutralizing agent, sodium formate, calcium formate, sodium
bicarbonate or ammonium sulfate. Liquid waste is collected at the
end of this step.
(10) A dyeing and fatliquoring step in which liquid waste and chemicals
ordinarily added are used. The dyeing and fatliquoring step
employs at least one of melamine, dicyanodiamide, a syntan, a
vegetable tanning agent, a synthetic fatliquoring agent, a sulfited
fatliquor, a sulfated fatliquor, a cationic fatliquor, neatsfoot oil or
lecithin. Liquid waste is collected at the end of this step.
(11) A water washing step in which liquid waste remaining in the drum
is used.
The liquid waste referred to in the foregoing steps is generated by each
individual step, namely, pre-soaking, soaking, unhairing, liming, re-liming,
deliming, bating, pickling, tanning, degreasing, re-tanning, neutralizing, dyeing,
fatliquoring and water washing steps, or a combination of two or more steps.
In operation, liquid waste is recycled at least once in the foregoing
process.
In the process of leather production with waste liquids, the combination
of some steps does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the filtration of a
waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the precipitation
of a waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the pressurization
of a waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the aeration of a
waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the stirring of a
waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the chemical
treatment of a waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the biological
treatment of a waste liquid does not substantially affect the efficacy of the process.
In the process of leather production with waste liquids, the combined use
of a waste liquid and fresh water does not substantially affect the efficacy of the
process.
The waste liquids contain plentiful ingredients that are favorable for
leather production, such as lime, deliming agents, soaking agents, liming agents,
sulfides, acids, enzymes, tanning agents, saponified substances, and amino acids.
For example, amino acids and saponified substances can be used to fill collagen
fibers, which can improve the quality of finished products.
In the process of leather production with waste liquids, if the waste
liquids are treated with procedures such as filtration, precipitation, compression,
stirring, aeration, chemical treatment and biological methods, these procedures will
likely change the composition of the waste liquids. Therefore, a step would need to
be adjusted accordingly when a treated waste liquid is used.
The original waste liquids used in the present process are generated from
pre-soaking, soaking, unhairing, liming, re-liming, deliming, bating, pickling,
tanning, degreasing, re-tanning, neutralizing, dyeing, fatliquoring and water
washing procedures, or some of these steps. Typically, waste liquids from pre-
soaking and soaking contain soaking agents, NaCl, Na CO , degreasing agents,
saponified substances, hair, keratin, and mucins. With respect to the residual
contents in these waste liquids, the degreasing agents are typically 15% to 30% of
the original amount, 10% to 40% for soaking agents, and 20% to 50% for Na CO .
Waste liquids from unhairing, liming and re-liming procedures contain saponified
2- - + 2+
substances, salts, lime, liming agents, S , OH , Na , Ca , amino acids, enzymes
and amines. With respect to the residual contents in these waste liquids, the
residual content of lime is typically 30% to 65% of the original amount, and the
residual content of sulfides is typically 0.1 to 8.0 g/L. Waste liquids from deliming
and bating contain amino acids, deliming agents, degreasing agents, saponified
substances, enzymes, ammonium salts and amines. The residual content of
enzymes is typically 20% to 50% of the original amount, and the residual content
of ammonium salts is typically 20% to 40% of the original amount. Tanning waste
liquids contain tanning agents, salts, amino acids, and saponified substances. The
3+ -
residual content of Cr is typically 2.0 to 3.5 g/L, and Cl is typically 5.0 to 15 g/L.
+ 3+
Waste liquids from degreasing and re-tanning contain Na , Cr and tanning
agents. Neutralizing waste liquids contain neutral salts and the like. Waste liquids
from fatliquoring and dyeing contain chemical materials such as fatliquoring
agents, dyes and auxiliary dyeing agents. If these waste liquids are discharged
freely, these waste liquids will not only cause significant contamination to the
environment, but will also result in a great waste of resources.
The present process substantially overcomes the contamination problems
in the tanning industry, simplifies the tanning process, significantly reduces the
discharge of tanning waste liquids and solid wastes, saves water, conserves land
use for environmental protection, lowers required investments in environmental
protection facilities, reduces the use of chemical preparations for environmental
protection, and lowers human costs for environmental protection, saves on the use
of chemical materials in the tanning process, and improves product quality.
Brief Description of the Drawings
is a flow diagram of the process for producing leather with waste
liquids.
Detailed Description of Illustrative Embodiment(s)
The present process will be further described below with reference to
and the following examples.
Example 1
(Soaking Step)
As shown in in a soaking step, relative to the weight of raw hide,
the following components are added to a drum containing the raw hide: 160%
waste liquid collected from a previously performed soaking step, 0.24% ELIPO-S
(tradename for a composition comprising sodium dimethyldithiocarbonate, sodium
hexametaphosphate and polyphosphoric acid sodium salt; available from Biosk
(SQ) Chemicals Co., Limited, No. 6 Changjiang East Road, Shangqiu
Development Zone, Henan, China), 0.35% bactericide, 0.5% soaking agent, 0.25%
degreasing agent, 0.4% soda ash, and 0.2% soaking enzyme. The drum is then
rotated for 120 min. at a temperature of 22°C. The drum is then rotated for 15 min.
every hour, for 12 hours, with the rotation then stopped for 45 min. before
repeating this rotate/stop sequence each overnight hour. On the second day, the
drum is rotated continuously for 20 min., and the soaking step then ends.
Example 2
(Unhairing and Liming Step)
As shown in in an unhairing and liming step, relative to the
weight of soaked hide, the following components are added to the drum containing
the raw hide: 120% waste liquid collected from a previously performed unhairing
and liming step, 0.20% ELIPO-L (tradename for another composition comprising
sodium dimethyldithiocarbonate, sodium hexametaphosphate and polyphosphoric
acid sodium salt; available from Biosk (SQ) Chemicals Co., Limited), and 2.5%
liming agent DO-PRO (tradename for a composition comprising sodium silicate
and dimethyl sulfoxide; available from Biosk (SQ) Chemicals Co., Limited). The
drum is then rotated for 30 min. at a temperature of 15°C. 2.5% lime is then added
to the drum, and the drum is then rotated for 20 min. and then stopped for 20 min.
1.2% sodium sulfide is then added to the drum and the drum is rotated for 50 min.
The hair is then filtered for 150 min. The following components are then added to
the drum: 0.3% sodium sulfide, 0.1% NaHS, and 0.2% lime. The drum is then
rotated for 20 min., stopped for 20 min., and the rotate/stop sequence is repeated
one more time. The following components are then added to the drum: 20% waste
liquid collected from a previously performed unhairing and liming step, 0.03%
ELIPO-L, 0.2% sodium sulfide, 0.3% lime, 0.4% liming agent DO-PRO. The drum
is then rotated for 10 min., stopped for 20 min., and this rotate/stop sequence is
repeated five more times. The following components are then added to the drum:
65% waste liquid collected from a previously performed unhairing and liming step,
0.10% ELIPO-L, and 0.05% liming enzyme. The drum is then rotated for 5 min.
The drum is then rotated for 15 min. every hour for 12 hours, with the rotation then
stopped for 45 min. before repeating this rotate/stop sequence each overnight hour.
On the second day, the drum is rotated continuously for 30 min., and the unhairing
and liming step then ends.
Example 3
(Re-liming Step)
As shown in in a re-liming step, relative to the weight of unhaired
and limed hide, the following components are added to the drum: 180% waste
liquid collected from a previously performed re-liming step, 0.27% ELIPO-L. The
drum is then rotated for 5 min. The following components are then added to the
drum: 1.0% lime and 1.5% liming agent DO-PRO. The drum is then rotated for 10
min., and then rotated for 2 min. and stopped for 58 min., and this rotate/stop
sequence is repeated four more times. The re-liming step then ends.
Example 4
(Deliming and Bating Step)
As shown in in a deliming and bating step, relative to the weight
of limed hide, the following components are added to the drum: 80% waste liquid
collected from a previously performed deliming and bating step, 0.12% ELIPO-L,
0.2% degreasing agent and 1.5% deliming agent. The drum is then rotated for 30
min. 0.1% bating enzyme is then added to the drum, and the drum is then rotated
for 30 min. The deliming and bating step then ends.
Example 5
(Degreasing Step)
The hide is shaved between the pickling and tanning step and the present
degreasing step. As shown in in the degreasing step, relative to the weight
of shaved hide, 200% waste liquid collected from a previously performed
degreasing step and 0.3% ELIPO-L are added to the drum. The drum is then
rotated for 10 min. at a temperature of 40°C. 0.3% degreasing agent and 0.3%
oxalic acid are then added to the drum, and the drum is then rotated for 60 min.
The degreasing step then ends.
Example 6
(Re-tanning Step)
As shown in in a re-tanning step, relative to the weight of shaved
hide, the following components are added to a drum: 150% waste liquid collected
from a previously performed re-tanning step, 0.22% ELIPO-L and 0.3% formic
acid are added to the drum. The drum is then rotated for 10 min. at a temperature
of 25°C. 1.0% aliphatic aldehyde is then added to the drum, and the drum is then
rotated for 30 min. The following components are then added to the drum: 2.0%
chromium powder, 1.5% re-tanning agent, and the drum is then rotated for 60 min.
1.0% sodium formate is then added to the drum, and the drum is then rotated for 20
min. 0.2% baking soda and 0.3% liming agent DO-PRO are then added to the
drum, and the drum is then rotated for 60 min. The drum is stopped for 8 hours. On
the second day, the drum is rotated for 20 min. The re-tanning step then ends.
Example 7
(Neutralizing Step)
As shown in in a neutralizing step, relative to the weight of
shaved hide, the following components are added to the drum: 180% waste liquid
collected from a previously performed neutralizing step, 0.27% ELIPO-L, 2.0%
neutralizing agent, and 1.5% sodium formate. The drum is then rotated for 30 min.
0.3% liming agent DO-PRO and 0.5% softening agent are then added to the drum,
and the drum is then rotated for 60 min. The neutralizing step then ends.
Example 8
(Dyeing and Fatliquoring Step)
As shown in in a dyeing and fatliquoring step, relative to the
weight of shaved hide, the following components are added to the drum: 50%
waste liquid collected from a previously performed dyeing and fatliquoring step,
0.08% ELIPO-L, 2.0% acrylic acid re-tanning agent, and 2.0% filler (bulking
agent). The drum is then rotated for 30 min. at a temperature of 35°C. The
following components are then added to the drum: 3.5% cyanoguanidine re-
tanning agent, 1.5% superlight synthetic filler, 4.0% mimosa extract, 2.0%
displacement tannin, and 2.0% dye. The drum is then rotated for 80 min. 150%
waste liquid and 0.23% ELIPO-L are then added to the drum, and the drum is then
rotated for 10 min. at a temperature of 50°C. The following components are then
added to the drum: 2.5% compound fatliquoring agent, 2.5% lecithin, 1.5%
synthetic fatliquoring agent, 0.5% neatsfoot oil. The drum is then rotated for 60
min. 1.5% acetic acid and 1.0% formic acid are then added to the drum in three
batches, with each batch added 20 min. apart. The dyeing and fatliquoring step
then ends.
Example 9
(Pre-soaking Step)
As shown in in a pre-soaking step, relative to the weight of raw
hide, 150% waste liquid collected from a previously performed deliming and
bating step is added to the drum, as well as 0.15% ELIPO-S, 0.3% bactericide,
0.2% soaking agent, 0.2% degreasing agent, 0.3% soda ash (sodium carbonate).
The drum is then rotated for 180 min. at a temperature of 22°C. The pre-soaking
step then ends.
Example 10
(Unhairing and Liming Step)
As shown in in an unhairing and liming step, relative to the
weight of raw hide, 60% waste liquid collected from a previously performed
soaking step and 1.5% liming agent DO-PRO are added to the drum, and the drum
is then rotated for 30 min. The following components are then added to the drum:
1.8% lime, 20% waste liquid collected from a previously performed liming step,
and 0.1% ELIPO-L. The drum is then rotated for 10 min. 1.2% Na S is then added
to the drum, and the drum is then rotated for 20 min. 30% waste liquid collected
from a previously performed liming step and 0.05% ELIPO-L, and the hair is then
filtered for 120 min. The following components are then added to the drum: 0.75%
sodium sulfide, 0.3% NaHS, and 1.0% lime are then added to the drum. The drum
is then, rotated for 20 min., stopped for 20 min., and this rotate/stop sequence is
then repeated one more time. The following components are then added to the
drum: 20% waste liquid collected from a previously performed liming step, 0.03%
ELIPO-L, 0.2% sodium sulfide, 0.8% lime, and 0.8% liming agent DO-PRO. The
drum is then rotated for 10 min., stopped for 20 min., and this rotate/stop sequence
is then repeated five more times. The following components are then added to the
drum: 65% waste liquid collected from a previously performed liming step, 0.15%
ELIPO-L, and 0.1% liming enzyme. The drum is then rotated for 5 min. The drum
is then rotated for 15 min. every hour for 13 hours, with the rotation then stopped
for 45 min. before repeating this rotate/stop sequence each overnight hour. The
unhairing and liming step then ends.
Example 11
(Re-liming Step)
As shown in in a re-liming step, relative to the weight of limed
hide, 120% waste liquid collected from a previously performed liming and re-
liming step [please confirm] and 0.15% ELIPO-L are added to the drum. The drum
is then rotated for 5 min. 0.4% liming agent DO-PRO is then added to the drum,
and the drum is then rotated for 10 min. The drum is then rotated for 2 min.,
stopped for 58 min., and this rotate/stop sequence is then repeated three more
times. The re-liming step then ends.
Example 12
(Pickling and Tanning Step)
As shown in in a pickling and tanning step, relative to the weight
of limed hide, the following components are added to the drum: 50% waste liquid
collected from a previously performed deliming and bating step, 0.1% ELIPO-L,
0.3% fungicide, and 0.5% salts. The drum is then rotated for 10 min. 0.5% formic
acid is then added to the drum, and the drum is then rotated for 10 min. 1.8%
sulfuric acid is then added to the drum, and the drum is then rotated for 90 min.
1.0% sodium formate is then added to the drum, and the drum is rotated for 30
min. 2.5% chromium powder is then added to the drum, and the drum is then
rotated for 30 min. 2.0% chromium powder is then added to the drum, and the
drum is then rotated for 60 min. 0.2% ELIPO-L is then added to the drum, and the
drum is then rotated for 30 min. 0.3% basifying agent is then added to the drum,
and the drum is then rotated for 4 hr. 80% waste liquid collected from a previously
performed pickling and tanning step and 0.12% ELIPO-L are then added to the
drum, and the drum is then rotated for 5 hr. at a temperature of 40°C. The pickling
and tanning step then ends.
Example 13
(Degreasing Step)
As shown in in a degreasing step, relative to the weight of
shaved, the following components are added to the drum: 80% fresh water, 120%
waste liquid collected from a previously performed degreasing step and 0.1%
ELIPO-L. The drum is then rotated for 10 min. at a temperature of 40°C. The
following components are then added to the drum: 0.1% degreasing agent, 0.2%
liming agent DO-PRO, and 0.15% formic acid. The drum is then rotated for 60
min. The degreasing step then ends.
Example 14
(Re-tanning Step)
As shown in in a re-tanning step, relative to the weight of shaved,
the following components are added to the drum: 100% fresh water, 100% waste
liquid collected from a previously performed re-tanning step, 0.15% ELIPO-L, and
0.5% formic acid. The drum is then rotated for 10 min. at a temperature of 35°C.
3.5% chromium powder and 1.0% re-tanning agent are then added to the drum, and
the drum is rotated for 60 min. 1.0% aliphatic aldehyde and 1.0% sodium formate
are then added to the drum, and the drum is then rotated for 20 min. 0.3% baking
soda and 0.2% liming agent DO-PRO are then added to the drum. The drum is then
rotated for 60 min. The drum is then stopped for 10 hours. On the second day, the
drum is rotated for 20 min. The re-tanning step then ends.
Example 15
(Neutralizing Step)
As shown in in a neutralizing step, relative to the weight of
shaved, the following components are added to the drum: 100% fresh water, 100%
waste liquid collected from a previously performed neutralizing step, 0.3% ELIPO-
L, 2.0% neutralizing tannin, 1.0% sodium formate, and 0.2% liming agent DO-
PRO. The drum is then rotated for 40 min at a temperature of 32°C. 0.3% baking
soda is then added to the drum, and the drum is then rotated for 60 min. The
neutralizing step then ends.
Example 16
(Dyeing and Fatliquoring Step)
As shown in in a dyeing and fatliquoring step, relative to the
weight of shaved hide, the following components are added to the drum: 20% fresh
water, 30% waste liquid collected from a previously performed dyeing and
fatliquoring step, 0.05% ELIPO-L, 2.0% acrylic acid re-tanning agent, and 2.0%
filler (bulking agent). The drum is then rotated for 30 min. at a temperature of
°C. The following components are then added to the drum: 4.5%
cyanoguanidine re-tanning agent, 1.5% superlight synthetic filler, 4.0% mimosa
extract, 2.0% displacement tannin, and 2.0% black dye. The drum is then rotated
for 80 min. The following components are then added to the drum: 100% waste
liquid collected from a previously performed dyeing and fatliquoring step, 50%
fresh water, and 0.45% ELIPO. The drum is then rotated for 10 min. at a
temperature of 50°C. The following components are then added to the drum: 2.8%
compound fatliquoring agent, 2.8% lecithin, 1.5% synthetic fatliquoring agent, and
0.5% neatsfoot oil. The drum is then rotated for 60 min. 1.2% acetic acid and 1.0%
formic acid are then added to the drum in three batches, with each batch added 20
min. apart The dyeing and fatliquoring step then ends.
Most of the chemical materials used in the above examples are available
from Biosk (SQ) Chemicals Co., Limited, including ELIPO-L, ELIPO-S and DO-
PRO.
is an overview of a leather production process 100 employing
recycling. As shown in process 100 of there can be a pre-soaking step 110,
wherein liquid waste 114 is collected in a reservoir, vessel, container, or drum at
step 112 (in any of the forgoing steps, a “drum” can be any type of vessel for
capturing the referenced material). At step 111, this liquid waste is employed in
future pre-soaking steps or other steps. Process 100 can comprise a soaking step
115, in which liquid waste 119 is collected in a vessel during step 117, and
employed in future soaking or other steps in step 116. Process 100 can comprise an
unhairing and liming step 120, in which liquid waste 124 is collected in a vessel
during step 122, and employed in future unhairing and liming or other steps in step
121. Process 100 can comprise a re-liming step 125, in which liquid waste 129 is
collected in a vessel during step 127, and employed in future unhairing and liming
or other steps in step 126.
Process 100 can comprise a deliming and bating step 130, in which liquid
waste 134 is collected in a vessel during step 132, and employed in future deliming
and bating or other steps in step 131. Process 100 can comprise a pickling and
tanning step 135, in which liquid waste 139 is collected in a vessel during step 137,
and employed in future pickling and tanning or other steps in step 136. Process 100
can comprise a degreasing step 140, in which liquid waste 144 is collected in a
vessel during step 142, and employed in future degreasing or other steps in step
141. Process 100 can comprise a re-tanning step 145, in which liquid waste 149 is
collected in a vessel during step 147, and employed in future re-tanning or other
steps in step 146.
Process 100 can comprise a neutralizing step 150, in which liquid waste
154 is collected in a vessel during step 152, and employed in future neutralizing or
other steps in step 151. Process 100 can comprise a dyeing and fatliquoring step
155, in which liquid waste 159 is collected in a vessel during step 157, and
employed in future dyeing and fatliquoring or other steps in step 156.
In some embodiments, a washing step 160 of process 100 in is
present, wherein the hide is washed with water. In some embodiments, the waste
liquid from washing is collected, and in some embodiments the liquid waste of
other steps in process 100 is used in washing step 160. Liquid waste 164 is
collected in a vessel at step 162, and is employed in future washing steps at 161. In
some embodiments, the liquid waste is employed in other steps. Depending on the
chosen embodiment, a washing step 160 can be performed at different points of
processes 100. In some embodiments, a washing step can be performed multiple
times during process 100.
While particular elements, embodiments and applications of the present
invention have been shown and described, it will be understood, that the invention
is not limited thereto since modifications can be made by those skilled in the art
without departing from the scope of the present disclosure, particularly in light of
the foregoing teachings.
Claims (14)
1. A process for the production of leather comprising at least one of the following steps: (a) pre-soaking a raw hide and collecting the pre-soaking waste liquid; (b) soaking the hide and collecting the soaking waste liquid; (c) unhairing and liming the hide and collecting the unhairing and liming waste liquid; (d) re-liming the hide and collecting the re-liming waste liquid; (e) deliming and bating the hide and collecting the deliming and bating waste liquid; (f) pickling and tanning the hide and collecting the pickling and tanning waste liquid; (g) degreasing the hide and collecting the degreasing waste liquid; (h) re-tanning the hide and collecting the re-tanning waste liquid; (i) neutralizing the hide and collecting the neutralizing waste liquid; (j) dyeing and fatliquoring the hide and collecting the dyeing and fatliquoring waste liquid; and (k) washing the hide with water and collecting the washing waste liquid, wherein the collected waste liquid from the at least one step is recycled to at least one step.
2. The leather production process of claim 1, wherein the waste liquid collected from the at least one step is recycled to the same at least one step.
3. The leather production process of claim 1, wherein the process comprises at least two of steps (a) – (k) and the waste liquid collected from at least one of steps (a) – (k) is recycled to at least one of another of steps (a) – (k).
4. The leather production process of claim 1, wherein the pre-soaking step employs at least one of a soaking agent, a bactericide, a degreasing agent, salt or an alkali.
5. The leather production process of claim 1, wherein the soaking step employs at least one of a soaking agent, an enzyme, a bactericide, a degreasing agent, salt or an alkali.
6. The leather production process of claim 1, wherein the unhairing and liming step employs at least one of a liming agent, an enzyme, lime, a lime dispersant, sodium hydrosulfide, sodium sulfide, a degreasing agent, salt or an alkali.
7. The leather production process of claim 1, wherein the re-liming step employs at least one of a liming agent, an enzyme, lime, a lime dispersant, sodium hydrosulfide, sodium sulfide, a degreasing agent or an alkali.
8. The leather production process of claim 1, wherein the deliming and bating step employs at least one of a deliming agent, an enzyme, a lime dispersant, a degreasing agent, ammonium sulfate or an acid.
9. The leather production process of claim 1, wherein the pickling and tanning step employs at least one of a degreasing agent, salt, a fungicide, an acid, a fatliquoring agent, a cross-linking agent, chrome powder, a basifying agent or sodium formate.
10. The leather production process of claim 1, wherein the degreasing step employs at least one of a degreasing agent, formic acid or oxalic acid.
11. The leather production process of claim 1, wherein the re-tanning step employs at least one of chrome powder, a tanning agent, a protein filling agent, an aliphatic aldehyde or an acrylic resin tanning agent.
12. The leather production process of claim 1, wherein the neutralizing step employs at least one of a neutralizing agent, sodium formate, calcium formate, sodium bicarbonate or ammonium sulfate.
13. The leather production process of claim 1, wherein the dyeing and fatliquoring step employs at least one of melamine, dicyanodiamide, a syntan, a vegetable tanning agent, a synthetic fatliquoring agent, a sulfited fatliquor, a sulfated fatliquor, a cationic fatliquor, neatsfoot oil or lecithin.
14. The leather production process of claim 1, wherein the efficacy of the process is unaffected by combined use of a waste liquid and fresh water. LEATHER PRODUCTION USING WASTE LIQUIDS
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201510826825.3 | 2015-11-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
NZ726380A true NZ726380A (en) |
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