Horn meal hydrolysate–chromium complex as a high exhaust chrome tanning agent––pilot scale studies

The manufacturing process to transform hides into leather requires a series of chemical and mechanical operations. Fleshings represent one of the most important byproduct of the leather compartment. They are mainly constituted of raw collagen and through an alkaline hydrolysis a collagenous solution is obtained. In this work, an experimental activity research was performed for assessing the feasibility of the reuse of the collagen hydrolizate solution in the tanning phase. The hydrolizate has been used in combination with chromium salts to obtain bovine upper leather up to a dosage of 20% of solution (68% dry protein matter content) on the fleshed hide weight. Following a laboratory scale screening of the optimal operating conditions, crust leathers have been obtained on pilot scale. The final leather shows similar properties to those of the traditionally tanned leather in terms of technical and mechanical properties. Furthermore, a dry tannage is feasible, thus avoiding the production of effluents, and it is possible to adopt a retannage/dyeing/fatliquoring characterized by a lower consumption of chemicals in comparison with the standard procedure. The results obtained indicate the use of the collagen hydrolizate in the tanning phase as an interesting route for valorisation of fleshings.

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Zeolite-chrome tanning: From laboratory to pilot scale

Oxide Based Materials - New sources, novel phases, new applications - Studies in Surface Science and Catalysis ◽

10.1016/s0167-2991(05)80148-x ◽

2005 ◽

pp. 189-198

Author(s):

P. Ciambelli ◽

D. Sannino ◽

B. Naviglio ◽

A.M. Manna ◽

V. Vaiano ◽

...

Keyword(s):

Pilot Scale ◽

Chrome Tanning

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SYNTHESIS OF CHROME TANNING AGENT IN PRESENCE OF OLIGO - AND POLYSACCHARIDES

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt.20216405.6350 ◽

2021 ◽

Vol 64 (5) ◽

pp. 63-70

Author(s):

Vyacheslav I. Chursin ◽

Alena O. Zaitseva

Keyword(s):

Sulfuric Acid ◽

Physical And Mechanical Properties ◽

Reducing Agents ◽

Oxidation Products ◽

Masking Effect ◽

Sodium Dichromate ◽

Chromium Complex ◽

Synthesis Conditions ◽

Incomplete Oxidation ◽

Chrome Tanning

The conditions for the synthesis of chrome tanning agent during the reduction of sodium dichromate with oligo - and polysaccharides have been investigated. The synthesis of the tanning agent is based on the reduction of hexavalent chromium Cr (VI) in the form of sodium dichromate with reducing agents from the class of vegetable oligo- and polysaccharides with a different sequence of their introduction into the reaction mixture in the presence of sulfuric acid. The introduction of sulfuric acid was carried out gradually to avoid overheating and splashing of the reaction mixture, since the reduction reaction is accompanied by a significant thermal effect. Glucose, maltodextrin and pectin were used as reducing agents. The properties of the obtained products were evaluated by spectrophotometry, conductometry, and analytical methods. It has been shown that the use of native pectin leads to the formation of a gel like mass due to the coordination of the functional groups of galacturonic acid, which is part of the pectin, with chromium atoms. Pretreatment of pectin with a citric acid solution and optimization of synthesis conditions made it possible to obtain a chromium tanning agent that does not contain unreduced chromium. The influence of oligosaccharides on the properties of chromium tanning agents, including their ability to dissolve, is considered. It is shown that the reduction of sodium dichromate with maltodextrin during the reaction results in the formation of incomplete oxidation products of the oligosaccharide, which cause the masking effect of the chromium complex and increase in the resistance of the tanning agent to the action of alkaline reagents used to increase in the basicity during tanning. Experimental samples of chrome tanning agent in dry form were obtained and their leatherprocessing characteristics were studied. The results of technological tests have confirmed the theoretical propositions, according to which the high hydrothermal stability of the leather semifinished product, the almost complete depletion of the processing solution and the required physical and mechanical properties of the finished leather are achieved by introducing the products of incomplete oxidation of oligosaccharides into the inner sphere of the chromium complex.

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Pilot-Scale Study on Masking Agents for Titanium Tanning

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.203 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 203-207

Author(s):

Monica Puccini ◽

Maurizia Seggiani ◽

Christian Pomelli ◽

Sandra Vitolo

Keyword(s):

Pilot Scale ◽

Titanyl Sulfate ◽

Shrinkage Temperature ◽

Chrome Tanning ◽

Physical Testing ◽

Tanning Process ◽

Masking Agents ◽

Temperature Scanning ◽

The Many ◽

Almost All

The many advantages offered by chrome tanning justify its widespread use for production of almost all types of leather. However, the traditional chromium (III) tanning process is constantly under threat from the pressure of legislation, and ever-tightening restrictions require to minimize chromium-containing effluents discharge and chromium-containing wastes production. Recently, the manufacture and use of chromium (III) free tanning agents compounds have been studied intensively. Among these, Titanium (IV)-based salts is one of the most promising substitutes.In this study, the use of titanyl sulfate as tanning agent for the production of high-quality bovine upper leather was investigated. In order to optimize the titanium tanning performances, a comparative evaluation, on pilot-scale, of citrate and lactate ions as masking agents was performed.The developed process has been validated through various analyses of the obtained crust leathers such as shrinkage temperature, scanning electron microscopy, and physical testing. The final leather obtained with the innovative method shows similar properties to those of the conventional tanned leather in terms of technical and mechanical properties.

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Upscaling of foam forming technology for pilot scale

TAPPI Journal ◽

10.32964/tj18.8.461 ◽

2019 ◽

Vol 18 (8) ◽

Cited By ~ 1

Author(s):

JANI LEHMONEN ◽

TIMO RANTANEN ◽

KARITA KINNUNEN-RAUDASKOSKI

Keyword(s):

Production Efficiency ◽

Strength Loss ◽

Pilot Scale ◽

Foam Density ◽

Forming Process ◽

Production Scale ◽

Forming Technology ◽

Wet Pressing ◽

Foam Forming ◽

Board Industry

The need for production cost savings and changes in the global paper and board industry during recent years have been constants. Changes in the global paper and board industry during past years have increased the need for more cost-efficient processes and production technologies. It is known that in paper and board production, foam typically leads to problems in the process rather than improvements in production efficiency. Foam forming technology, where foam is used as a carrier phase and a flowing medium, exploits the properties of dispersive foam. In this study, the possibility of applying foam forming technology to paper applications was investigated using a pilot scale paper forming environment modified for foam forming from conventional water forming. According to the results, the shape of jet-to-wire ratios was the same in both forming methods, but in the case of foam forming, the achieved scale of jet-to-wire ratio and MD/CD-ratio were wider and not behaving sensitively to shear changes in the forming section as a water forming process would. This kind of behavior would be beneficial when upscaling foam technology to the production scale. The dryness results after the forming section indicated the improvement in dewatering, especially when foam density was at the lowest level (i.e., air content was at the highest level). In addition, the dryness results after the pressing section indicated a faster increase in the dryness level as a function of foam density, with all density levels compared to the corresponding water formed sheets. According to the study, the bonding level of water- and foam-laid structures were at the same level when the highest wet pressing value was applied. The results of the study show that the strength loss often associated with foam forming can be compensated for successfully through wet pressing.

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Application of a Pilot-Scale Pulsed Electrocoagulation system to OCC-Based Paper Mill Effluent

TAPPI Journal ◽

10.32964/tj8.3.14 ◽

2009 ◽

Vol 8 (3) ◽

pp. 14-20 ◽

Cited By ~ 2

Author(s):

YUAN-SHING PERNG ◽

EUGENE I-CHEN WANG ◽

SHIH-TSUNG YU ◽

AN-YI CHANG

Keyword(s):

Water Quality ◽

Quality Indicators ◽

Paper Mill ◽

Pilot Scale ◽

Operating Conditions ◽

Optimal Dosage ◽

Water Quality Indicators ◽

Paper Mill Effluent ◽

Treated Effluent ◽

True Color

Trends toward closure of white water recirculation loops in papermaking often lead to a need for system modifications. We conducted a pilot-scale study using pulsed electrocoagulation technology to treat the effluent of an old corrugated containerboard (OCC)-based paper mill in order to evaluate its treatment performance. The operating variables were a current density of 0–240 A/m2, a hydraulic retention time (HRT) of 8–16 min, and a coagulant (anionic polyacrylamide) dosage of 0–22 mg/L. Water quality indicators investigated were electrical con-ductivity, suspended solids (SS), chemical oxygen demand (COD), and true color. The results were encouraging. Under the operating conditions without coagulant addition, the highest removals for conductivity, SS, COD, and true color were 39.8%, 85.7%, 70.5%, and 97.1%, respectively (with an HRT of 16 min). The use of a coagulant enhanced the removal of both conductivity and COD. With an optimal dosage of 20 mg/L and a shortened HRT of 10 min, the highest removal achieved for the four water quality indicators were 37.7%, 88.7%, 74.2%, and 91.7%, respectively. The water qualities thus attained should be adequate to allow reuse of a substantial portion of the treated effluent as process water makeup in papermaking.

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Pilot-scale combustion studies with kraft lignin in a powder burner and a CFB boiler

TAPPI Journal ◽

10.32964/tj9.6.24 ◽

2010 ◽

Vol 9 (6) ◽

pp. 24-30 ◽

Cited By ~ 2

Author(s):

NIKLAS BERGLIN ◽

PER TOMANI ◽

HASSAN SALMAN ◽

SOLVIE HERSTAD SVÄRD ◽

LARS-ERIK ÅMAND

Keyword(s):

Circulating Fluidized Bed ◽

Black Liquor ◽

Chloride Content ◽

Pilot Scale ◽

High Energy ◽

Kraft Lignin ◽

High Energy Density ◽

Alkali Chloride ◽

Cfb Boiler ◽

Solid Biofuel

Processes have been developed to produce a solid biofuel with high energy density and low ash content from kraft lignin precipitated from black liquor. Pilot-scale tests of the lignin biofuel were carried out with a 150 kW powder burner and a 12 MW circulating fluidized bed (CFB) boiler. Lignin powder could be fired in a powder burner with good combustion performance after some trimming of the air flows to reduce swirl. Lignin dried to 10% moisture content was easy to feed smoothly and had less bridging tendencies in the feeding system than did wood/bark powder. In the CFB boiler, lignin was easily handled and cofired together with bark. Although the filter cake was broken into smaller pieces and fines, the combustion was not disturbed. When cofiring lignin with bark, the sulfur emission increased compared with bark firing only, but most of the sulfur was captured by calcium in the bark ash. Conventional sulfur capture also occurred with addition of limestone to the bed. The sulfur content in the lignin had a significantly positive effect on reducing the alkali chloride content in the deposits, thus reducing the high temperature corrosion risk.

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