Tannery Process Research Articles

Treatment of salt from hides curing stage by electrocoagulation for use in the pickling stage of the tanning industry

The raw materials for the tanning industry, namely hides and skins, are preserved (curing stage) and carried with common salt, i.e., sodium chloride (NaCl). Proceeding to conversion into leather, pickling is a key stage of the tannery process, which entails high demand of water and salt. In this work, the salt-derived brine (SdB) generated from the curing of hides was treated by iron-driven electrocoagulation (EC), aiming at its later application in the pickling stage of the tanning industry, promoting a transition to zero waste emission policy. Focusing on reducing the brine's total organic carbon (TOC), central composite rotational design and response surface methodology were adopted to study the effect of electrolysis time (6.2–14.2 min) and current density (74–431 A·m−2) on the treatment of the SdB (≅ 7.5 % wt. NaCl). The quality of the treated brines was then assessed in pickling trials and compared with virgin brine. 68–83 % removal of TOC from the SdB were achieved under electrolysis time ranging 6.2–14.2 min and current density ranging 126–252 A·m−2. Under these operating ranges the quality of the wet-blue leathers was guaranteed. Lowest power consumption (0.44 kWh·m−3) was achieved under electrolysis time of 6 min and current density of 126 A·m−2, yielding 68 % removal of TOC. Moreover, the shrinkage temperature of the hides was improved with treated brine (103.5 °C–110.5 °C) compared to virgin brine (103.0 °C). The present study provides strong evidence that contaminated salt from the curing stage can be valorised within the tanning industry through electrocoagulation treatment and then used in another production stage, instead of being landfilled.

Sustainable Chromium Encapsulation: Alkali Activation Route

This article highlights recent experimental advances in the use of inorganic substances in the encapsulation of pollutants and, in particular, discusses the potential applicability and constraints of the geopolymerization process for the treatment of wastewater containing chromium. A great percentage of waste containing chromium salts is produced by the leather industry during the tannery process. Such industrial waste is in the form of liquor containing almost 40% of the initial chromium combined with many other pollutants. The stabilization/solidification (S/S) treatment of this type of waste must be combined with chromium encapsulation in an economic, environmentally friendly and efficient process to be industrially feasible. Here we present a novel process in which the wastewater is used as a component of the formulation together with a clay by-product and with the addition of NaOH pellets with the goal of a no-water plus no-waste technology approach. The final solidified “ceramic-like” material successfully immobilized the heavy metal cations as well as anions and macromolecules of surfactants, avoiding environmental damages to soil and groundwater. The article is completed by mentioning other S/S processes where wastewater has been treated and the resulting sludge encapsulated. The future of the S/S technologies in the tannery industry should progress in the direction of significantly reducing the amount of wastewater directed to the treatment plants, with associated reductions in transport and their CO2 emissions. This article intends to be a contribution in the direction of preventing waste, aligning circular economy and waste management objectives.

First Glimpse into the Genomic Characterization of People from the Imperial Roman Community of Casal Bertone (Rome, First-Third Centuries AD).

This paper aims to provide a first glimpse into the genomic characterization of individuals buried in Casal Bertone (Rome, first–third centuries AD) to gain preliminary insight into the genetic makeup of people who lived near a tannery workshop, fullonica. Therefore, we explored the genetic characteristics of individuals who were putatively recruited as fuller workers outside the Roman population. Moreover, we identified the microbial communities associated with humans to detect microbes associated with the unhealthy environment supposed for such a workshop. We examined five individuals from Casal Bertone for ancient DNA analysis through whole-genome sequencing via a shotgun approach. We conducted multiple investigations to unveil the genetic components featured in the samples studied and their associated microbial communities. We generated reliable whole-genome data for three samples surviving the quality controls. The individuals were descendants of people from North African and the Near East, two of the main foci for tannery and dyeing activity in the past. Our evaluation of the microbes associated with the skeletal samples showed microbes growing in soils with waste products used in the tannery process, indicating that people lived, died, and were buried around places where they worked. In that perspective, the results represent the first genomic characterization of fullers from the past. This analysis broadens our knowledge about the presence of multiple ancestries in Imperial Rome, marking a starting point for future data integration as part of interdisciplinary research on human mobility and the bio-cultural characteristics of people employed in dedicated workshops.

Effect of using fresh palm oil and used palm oil as a fat liquoring agent to the chemical quality of leather from tilapia fish skin

Tilapia skin has a high value in the form of tanned tilapia skin. One of the factors that play an important role in the tanning process is the using of tanning agents. This research was carried out by vegetable tanning to the tilapia fish skin using selected concentration of fresh palm oil and used palm oil. The study aims to find out the chemical quality of leather through the using of fresh and used palm oil as fat liquoring agent in the vegetable tannery process. The same concentration of fresh palm oil (10%), and used palm oil (10%) were used in this study. The parameter of fat content, and water content as chemical quality was observed in triplicates. Based on the results, the fat content of the leather using fresh palm oil (19.265%) was significantly increased (p<0.05) compared to used palm oil (15.825%), while the water content was also significantly different (p<0.05). In conclusion, the addition of palm oil improved the moisture of tilapia fish skin and become softer that can be used for commercial products, and it became the alternative material that could be use in vegetable tannery processing.

Effect of using fresh palm oil and used palm oil as a fatliquoring agent to the physical quality of tilapia fish skin in vegetable tannery

Fish skin is one of the alternative materials to replace the common animal skin that used in the leather tannery. This research was carried out by vegetable tanning to the tilapia fish skin using selected concentration of fresh palm oil and used palm oil. The study aims to find out the physical quality of leather through the using of fresh and used palm oil as fatliquoring agent in the vegetable tannery process. The same concentration of fresh palm oil (5%) and used palm oil (5%) were used in this study. The parameter of tensile strength, elongation, and shrinkage temperature as physical quality was observed in triplicates. Based on the results, tensile strength and leather elongation were significantly increased, while the shrinkage temperature was not significantly affected. In conclusion, the addition of palm oil caused the increasing tilapia fish skin quality that can be used for commercial products, and it became the alternative material that could be use in vegetable tannery processing.

Pulmonary Dysfunction Augmenting Bacterial Aerosols in Leather Tanneries of Punjab, Pakistan.

BackgroundParticulate matter–associated microbes in the workplace are a burning issue in occupational toxicology. Studies have reported on respiratory infections among tannery cohorts. This study uniquely presents measurements of airborne bacterial concentrations associated with varied particulate-matter sizes, their exposure, and consequent severity in occupational respiratory problems, all for different microenvironments within leather tanneries.MethodsAnalyses included molecular identification of isolates, computation of mass median aerodynamic diameter of aerosols, tannery process–exposure dose (TPED) to bacterial aerosols, and spirometry and symptom assessment of impaired pulmonary function.ResultsThe highest bacterial concentrations were for rawhide treatment and finishing units, showing 3.6×103 and 3.7×103 CFU/m3, respectively. Identified bacterial species included Ochrobactrum pseudogrignonense, Neisseria bacilliformis, Enterobacter cloacae, Alcaligenes faecalis, Klebsiella pneumoniae, and Corynebacterium spp. Maximum and minimum values of mass median aerodynamic diameter were 8.3 µm and 0.65 µm for buffing and snuffing and production units, respectively. The highest TPED was 1,516.9 CFU/kg for finishing units. Respiratory symptoms in order of incidence were dyspnea > phlegm > cough > wheezing and tachypnea (equivalent). Bronchodilator measurements of FEV1, FVC, and PEF represent decline in lung function. Of 26 patients identified with COPD, most were working in rawhide treatment.ConclusionWe conclude that exposure–infection synergy is also a cause of pulmonary ailments and COPD development, rather than the better-known exposure–smoking synergy.

Production, purification and characterization of biosurfactant isolated from Bacillus oceanisediminis H2

Abstract The strain Bacillus oceanisediminis H2, which was isolated from tannery processing industrial wastelands, grown on biosurfactant production media supplemented with glucose as carbon source and urea as nitrogen source was successful in the production of a crude biosurfactant. The crude biosurfactant was purified using silica-gel column chromatography and thin layer chromatography (TLC), which was then lyophilized for further analysis. TLC of both the crude and purified biosurfactant showed similar Rf values of 0.678 (of one of the spots) and 0.614 respectively. The solid purified product was then subjected to FTIR and LC-MS analysis which confirmed that the purified biosurfactant is surfactin by nature. The crude biosurfactant produced has the ability to reduce surface tension to 46.909 mN/m from 72 mN/m as that of water.

Evaluation of the aerobic and anaerobic degradation of an industrial effluent from vegetable tannery processing of leather on batch reactors

&lt;p&gt;In this study, the aerobic and anaerobic biodegradability of the industrial wastewater from the vegetable tanning process were evaluated. Water from a food wastewater treatment system was used as seed inoculum for the aerobic process and mature granular methanogenic sludge from a brewery industrial wastewater plant was used for the anaerobic process. The water from the tanning industry had a biological to chemical oxygen demand ratio of 33% with values of total chemical oxygen demand (COD) in the range of 342000 mg O2/L and total dissolved solids of 506595 mg/L. The assay of the tannery effluent under aerobic conditions resulted in a decrease of COD of 39.2% and a degradation of tannins lower than 12% after 26 days, while the anaerobic degradation showed a COD reduction of 65% with a 39% of degradation of tannins. The production of methane and Volatile Fatty Acids, during the anaerobic treatment, suggests a potential adaptation of biological organisms present in the mature anaerobic granular methanogenic sludge.&lt;/p&gt;&#x0D;

Analisis Potensi Jejak Karbon Limbah Cair dan Listrik Pada Proses Penyamakan Kulit

Leather is a product obtained from the conversion process of raw skin/hide into leather. The process generate a number of wastes with a high pollutant content, especially waste water. The waste contributes to the formation of carbon emission. Awareness on environmental sustainability also requires the industry to improve its production system to make it more eco-friendly. Improvements will increase production and the industry reputation. Before making improvements to the production system, it is necessary to carry out an analysis related to the carbon emissions produced in producing a product. The objectives of this study were to calculate carbon emission (carbon footprint) that generates in the leather tannery process and to give alternative strategy for the environmental improvement. The research used primary data and secondary data. This research was carried out with the processes identification, carbon emission sources identification, an analysis of the carbon emission potential amount, and a study of strategies to minimize carbon formation in the tannery. The results of the analysis showed that electricity and wastewater were sources of carbon in the production process of leather. The total of carbon emission formed in the leather tanning process was 1,692.17 kg CO2 eq per batch, where wastewater contributed more than electricity. Further analysis showed that 1 m2 of leather produced 8.08 kg CO2 eq of carbon. The strategies that can be taken to reduce carbon emissions are engineering processes, material substitution, and using eco-friendly materials. Keywords: carbon footprint, leather, tannery

Removal of Drugs in Polluted Waters with Char Obtained by Pyrolysis of Hair Waste from the Tannery Process.

The presence and final destination of pharmaceutical compounds in waters constitute one of the emerging events in current environmental chemistry. Two widely consumed compounds have been evaluated in this study, amoxicillin (AMOX) and diclofenac (DFC), at a concentration of 200 mg L–1. The presence of both in wastewater has been verified, generating problems in ecosystems and human health. Pyrolysis of hair waste from a tannery process was performed in a fixed-bed reactor. Char was obtained at different operating temperatures (300, 350, 400, and 450 °C), which underwent a characterization of heavy metals and elemental composition. An activation process was applied to the char obtained at 450 °C by means of physicochemical processes and with two chemical agents (KOH and K2CO3). For the removal of drugs, two separate tests were performed, one for 28 days and the other one for 4 h, to assess the efficiency and the percentage of removal. It was found that the char obtained at 450 °C is the one that removes most of both compounds: more than 90% of AMOX and more than 80% of DFC.

Tanning process promotes abiotic humification: separation and characterization of humic acid-like polymers complex.

Humic-like substances are essential components of soluble organic matter in tannery wastewater. However, the tannery process can promote the abiotic humification in wastewater. Therefore, it is of great significance to clarify the pathway and degree of abiotic humification and the properties of the as-derived humic acid-like (HAL) complex polymers in the tannery process in order to control the refractory organic compounds. In the present study, considering the catechol-Maillard system and commercial humic acid (HA) as control, the polyphenol-Maillard humification in the tannery process was simulated under the catalysis of MnO2. Moreover, physicochemical and spectroscopic techniques were used to characterize the separated fractions of HAL further. As a result, it was found that the catechol-Maillard system with small molecule organic matter as precursor had higher humification degree. Furthermore, the ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), and excitation-emission matrix (EEM) fluorescence spectrum of humic acid-like 0 (HAL0) derived from it was different from those of humic acid-like 1 and 2 (HAL1 and HAL2) of polyphenol-Maillard system, indicating the differences of polymer structure between them. In the polyphenol-Maillard system, tannin was the skeleton of polymerization or polycondensation reaction, and the high content of N and the H/C value of HAL2 indicated that in adding to amino acids, proteins promoted the humification, forming industry-specific HAL polymers with a high degree of aliphatic nature. Therefore, it can be concluded that controlling the raw materials in the tannery process (especially tannins), in order to reduce the occurrence of abiotic humification may be the key to improve the efficiency of wastewater treatment.

Enhanced mineralization of Reactive Black 5 by waste iron oxide via photo-Fenton process

Advanced oxidation process is a promising technology for the treatment of azo dye wastewater, owing to its high degradation performance and less secondary contamination. Herein, the mineralization of azo dye Reactive Black 5 (RB5) by the heterogeneous photo-Fenton process was investigated in a three-phase fluidized bed reactor. The waste iron oxide (denoted as BT) obtained from tannery wastewater process with Fenton’s reagent was selected as a heterogeneous catalyst. The introduction of BT to the UV/H2O2 process (UV/H2O2/BT) shows obviously higher mineralization efficiency because ferric complexes of carboxylic acid, the degradation intermediates of RB5, could be readily decomposed by UV irradiation. The decolorization was achieved by homogenous photo-Fenton reaction induced by leached iron, while the mineralization was contributed to heterogeneous oxidation. Under the conditions of 254 nm UV irradiation, 19.00 mM H2O2, 2.0 g L–1 catalyst loading and natural pH0 of 5.0, 90.2% TOC removal of RB5 could be achieved. The catalyst indicated an acceptable stability and reusability after four cycles. The proposed heterogeneous photo-Fenton process with stable performance is environmental-friendly for the mineralization of RB5.

Impact Of Leather Industries On Groundwater In Tamil Nadu With Special Reference To Vellore District

Tanning industry is a one of the traditional business industry in India. The leather and leather based industries can emphasize to be the world’s one of the largest industrial sector based upon a by-product. Leather and leather goods are vital role in the foreign exchange earnings. Tannery process unit is very important factor for enhancing the quality in leather production. On the other side, during this processes large quantum of toxic waste is disposed into the nature which invites vital threat to the environment at large. It leads to the contamination of water resources (both surface and ground water), soil resources and other flora and fauna. The rate of environmental degradation reflected by the decline of agricultural productivity and the quality of natural resources like water, soil, etc has decline at very high rate. The main focus of this paper is to emphasize the impact of leather industry on groundwater source in the study area. This study is descriptive in nature, simple statistical tools are used and the major finding will be addressed in this paper.

A hybrid treatment process for product recycling from tannery process effluent and soak liquor

The sulfate rich saline tannery effluent (SRSTE) was treated effectively using halophilic bacterial pretreatment followed by electrochemical oxidation (hybrid treatment). Aerobic degradation was done using halophilic bacterial consortia isolated from the tannery soak effluent, resulted in 76 % COD removal after 6 days. The remaining COD was reduced by electrochemical oxidation (EO). In electro oxidation process (without aerobic pretreatment), 24 h of electro-oxidation was needed to complete COD removal. The process efficiency was analysed through Fourier transform infrared spectroscopy (FTIR), high performance liquid chromatography (HPLC), total organic carbon (TOC) and chemical oxygen demand (COD). The reduction of sulfate could not be noticed in presence of halophilic bacteria in aerobic treatment. The energy consumption for COD removal was about 0.343 and 0.020 kW h/g1 in electrochemical oxidation and hybrid treatment process respectively. Besides, chloride loss was also higher in EO when compared to hybrid approach. Hybrid treatment process was proved to be an effective method for treating SRSTE. The mixed salt was recovered and used for dyeing purpose.

Physico-Chemical Characterization of Local Tannery Waste Water Before and After Flocculation Treatment

This paper presents the variation in physico-chemical properties of a local Maroua tannery effluent before and after a flocculation treatment. Tanning is a process that consists of the transformation of the animal skin into leather by using different baths which contain many chemical reagents and produces high quantity of liquid and solid waste. The used water of traditional tannery of Maroua is directly thrown in nature without any pre-treatment posing a potential risk to the environment and human health. Physico-chemical parameters such as temperature, pH and conductivity, Total suspended solids, Total hardness, chlorides, sulfides, nitrates,COD, BOD5 , ammonium ion, dissolve oxygen, turbidity, colour and odour were determined before and after aluminum sulfate powder flocculation treatment for effluents collected from soaking, liming, deliming and vegetable tanning stages of the tannery process. The results obtained showed that most of the physico-chemical parameters are higher than the international standard. The results obtained made it possible to classify these four effluents in order of toxicity as follows: Liming water &amp;gt; vegetable tanning water &amp;gt; deliming water &amp;gt; soaking water. The treatment of these waste waters by flocculation reduces the concentrations of certain pollutant loads such as TSS, turbidity, hardness, COD, BOD5, sulfate; but remains less effective on others such as nitrate, chloride and ammonium ion (8%). There is also a decrease in pH, an increase in dissolved oxygen and conductivity. The flocculation treatment thus considerably reduced the toxicity of these effluents, especially its organic load.

Preparation and characterization of activated carbon produced from tannery solid waste applied for tannery wastewater treatment.

The removal of toxic compounds (azo dyes) from dyeing wastewater was investigated by an environmentally friendly activated carbon produced from solid waste generated in the tannery process, the cattle hair (CHW), activated with H3PO4 (AC-CHW), suggesting a life cycle extension for this material from leather processing. Preliminary tests with aqueous solutions containing Acid Brown 414 (AB-414) and Acid Orange 142 (AO-142) removed 71.06% and 73.05%, respectively. The activated carbon was characterized by zeta potential (ZP), functional groups (FTIR), elemental composition, sorbent specific surface area, and pore size distribution (BET/BJH). The specific surface area showed low values when compared to commercial activated carbon, but average pore diameter was higher, which facilitates the adsorption of larger and complex molecules, such as those present in real wastewaters. Through SEM and FTIR, the presence of the toxic compounds studied in the AC-CHW after sorption process was observed, where the results indicated that the functional groups of -CH=CH- participated in the removal process for these compounds. The removal efficiency obtained with AC-CHW was 51.94% and 49.73% for the dyeing wastewater containing AB-414 and AO-142, respectively. The obtained results open a promising via to use AC-CHW as efficient eco-friendly sorbent for the treatment of leather wastewater.

Consortium of Microalgae for Tannery Effluent Treatment

Abstract Wastewater generated in tanneries have essential elements for microalgae growth, but it has also some toxic compounds that may hinder or restrain the growth of microalgae in this environment. This work tested microalgae consortium growth originating from a deactivated effluent treatment decanter of a complete tannery (beamhouse to finished leather) for the treatment of wastewater of a tannery processing wet-blue leather to finished leather. It was initially evaluated the growth of the microalgae consortium in the three effluents diluted in 50% distilled water: raw effluent (50RE50W), effluent after primary coagulation/flocculation (50PE50W), and effluent after primary and secondary biological treatment (50BE50W). After 16 days of cultivation, the 50PE50W presented the highest biomass concentration (1.77 g L−1). The highest removal values for effluents 50RE50W, 50PE50W and 50BE50W were 51.02%, 99.90%, 82.88%, and 91.75% for chemical oxygen demand (COD), N-NH3, TKN, and P-PO4-, respectively. It was verified low levels of nutrient removal in the raw effluent (100RE), since the consortium was not able to grow in this medium. Finally, at concentrations of 25RE75BE (25% raw effluent diluted with 75% effluent after the biological treatment) and 50RE50B (50% raw effluent diluted with 50% effluent after the biological treatment), effective removal values were reached. Biomass growth concentration up to 1.3 g L-1 and removal values for N-NH3, TKN, P-PO4, COD, total organic carbon (TOC) and biological oxygen demand (BOD5), of 99.90%, 79.36%, 87.82%, 14.26%, 35.82%, and 42.86%, respectively, were reached in 50RE50B.

Studying type wet blue tannery process for estimating environmental performance using the Life Cycle Analysis methodology: A Case Study in Mexico

Studying type wet blue tannery process for estimating environmental performance using the Life Cycle Analysis methodology: A Case Study in Mexico

P.3.f.022 - Subjective interview quality metrics predict scoring performance in the administration of the PANSS

The strain Bacillus oceanisediminis H2, which was isolated from tannery processing industrial wastelands, grown on biosurfactant production media supplemented with glucose as carbon source and urea as nitrogen source was successful in the production of a crude biosurfactant. The crude biosurfactant was purified using silica-gel column chromatography and thin layer chromatography (TLC), which was then lyophilized for further analysis. TLC of both the crude and purified biosurfactant showed similar Rf values of 0.678 (of one of the spots) and 0.614 respectively. The solid purified product was then subjected to FTIR and LC-MS analysis which confirmed that the purified biosurfactant is surfactin by nature. The crude biosurfactant produced has the ability to reduce surface tension to 46.909 mN/m from 72 mN/m as that of water.

Combined electrocoagulation/electrooxidation process for the COD removal and recovery of tannery industry wastewater

The efficiencies of electrooxidation (EO), electrocoagulation (EC) and combined EC/EO processes for the treatment and recovery of tannery wastewater were investigated. In this way, not only the effect of retention time and current density on the COD and color removal was investigated, but also, the recovery of effluent was investigated to provide a standard quality for effluent disposal and supply for agricultural and industrial uses. The results showed that the EO process was able to eliminate COD and color by 98.9 and 99.0%, respectively. The EC process at optimum conditions had the removal efficiencies of 82.2 and 68.3% for COD and color, respectively, which could not treat the effluent completely. While the EC process produces a wastewater with COD of 1620 mg/L that needs extra treatment for agriculture and reuse, the process of EO produces a wastewater with COD of about 92 mg/L, whose its organic loading is suitable for agricultural purposes but not appropriate for industrial uses. The combined EC/EO process can produce an effluent with COD ≤ 5 mg/L that has standard quality for disposal and use for agricultural needs as well as for reuse in tannery process. Moreover, the EC/EO process has low energy consumption of 18.2 kWh/m3 as compared with EO process with energy consumption of 60 kWh/m3. The combined EC/EO process is useful for the treatment of tannery wastewater so that the effluent can be used for industrial purposes. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 637–644, 2018