Use of fleshings-derived collagen in chrome tanning process

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

Leather manufacturing by using treated municipal wastewaters

Leather processing requires copious amounts of freshwater, approximately between 15 and 20 L per kg of raw hide. The possibility of reusing reclaimed municipal wastewaters in the leather production assumes a great significance, proving a sustainable solution to the conservation of the groundwater reserves. In the present work, a combination of a membrane bioreactor (MBR) and nanofiltration (NF) membrane processes was investigated for the municipal wastewater reclamation, and their performances were evaluated and designed to meet water quality criteria required by the wet stages of tanning process. The results showed that the municipal wastewaters treated by combing MBR and NF met the required quality criteria in terms of total/permanent hardness, Fe, Mn and ammonium contents. The quality of the leathers produced both on pilot and industrial scale using treated water did not show any significant difference in terms of physical and technical properties, and satisfied fully the tannery specifications

Dual mobility cup in hip arthroplasty: An in-depth analysis of joint registries.

AbstractAlthough total hip arthroplasty (THA) has shown successful results, instability remains a major complication. In recent years, dual mobility cups (DMC) have gained interest among clinicians thanks to its low rate of dislocation and good clinical results. The main aim of this work was to describe the accuracy of data on DMC from national and regional joint registries (JRs) and the available worldwide literature. We identified topics on DMC among JRs to propose a new harmonized and standardized section for DMC with the aim to understand its surveillance over the time. We extracted survival and implant data for a separate analysis. After performing a critical exclusion process, nine JRs were considered eligible and included for final synthesis; these were the results from the available worldwide data from JRs. In our study, eight analyzed JRs reported a slight increase in DMC use in the last decade. In all the JRs evaluated and the available articles, dislocation remains one of the main reasons for revision and re‐revision in hip arthroplasties. DMC is considered to be a valid construct increasingly used worldwide in primary and revision THA with the primary aim of reducing dislocation rates. Annual reports from JRs collect heterogeneous and low‐quality information about outcomes and surveillance of DMC, creating a burden for clinicians to extract comparable data from different JRs. Longer follow‐up and a systematic registering of DMCs with international registry harmonization are needed to monitor DMC outcomes

New tanning agents

New tanning agents active in leather tanning and retanning, obtained from renewable materials

Tanning agents

The present invention refers to the use as tanning agents for animal pelts of known furan derivatives, which are not toxic and biodegradable, and to a tanning process economically sustainable and comprising a phase of treatment of the pelts directly with aqueous solutions comprising said furan derivatives, obtained by hydrolysis of a lignocellulosic biomass

THERMOPLASTIC POLYMER COMPOSITION | [COMPOSITION POLYMÈRE THERMOPLASTIQUE]

The present invention relates in general to the field of thermoplastic polymeric materials, and more precisely it relates to novel thermoplastic; polymeric compositions defined better herein after that are useful for the manufacture, by hot melt extrusion, of biodegradable artefacts and packaging, compostable and having at the same time performances and costs comparable to those of the products obtained with the traditional non-biodegradable thermoplastic polymeric materials, such as the polyoleflns

Innovative pickle-free chrome tannage: development of the semi-industrial scale process and LCA analysis

An alternative pickle-chrome tannage step with a lower inherent potential environmental impact than the traditional one was developed. The innovative process is based on the use of tanning products containing chrome(III) salts with less astringency than the traditional ones. The use of sodium chloride and sulfuric acid is avoided and a significant reduction of chlorides and sulphates dissolved in the exhaust baths is obtained. The technical feasibility of the innovative chrome tannage process was experimentally explored. Several experimental activities have been performed, both on a pilot scale and on an semi-industrial scale, in order to assess the quality of the finished leather obtained by the new pickle-free tanning process. The results have shown that the finished leathers are comparable to the ones obtained by the traditional process in terms of physical-mechanical and technical properties. Besides, a LCA (Life Cycle Assessment) analysis was performed in order to check the actual reduction in environmental burdens due to the process proposed by the authors, in comparison with the traditional pickle-based one

Tannery wastewater sludge ash for the production of waterproofing membrane: a technical and environmental feasibility study

Sludge from tannery effluent treatment processes is a by-product of leather-making industry, in which chrome compounds are the most common used materials. The objective of this work was to investigate the effects and feasibility in the use of tannery sludge ash as a partial or total replacement of usual mineral filler such as in manufacture of waterproofing membranes. The effects of sludge ash on the morphology and mechanical properties of membranes were investigated. Leaching tests were carried out in order to guarantee that the fulfilment of “filler function” was done in respect with environmental criteria. Besides, a Life Cycle Assessment (LCA) analysis was performed in order to assess the environmental performances of the waterproofing membrane filled by tannery sludge ash in comparison with the conventionally filled membrane. The performances of the membranes and the results of environmental assessment indicate that tannery sludge ash may be used as total replacement of CaCO3 for waterproofing membranes

Sustainability in process innovation: development of a green tanning process supported by LCA methodology

As a response to the growing concerns about a variety of environmental issues expressed by public opinion and political bodies, the leather industry needs to support its market by environmental criteria as a guarantee of quality. For this reason, assessment tools as Life Cycle Assessment (LCA) methodology, which allow a more thorough knowledge of the products to the enterprises and can help to guide the environmental policies, are recommended (e.g. EC Directive on Ecologic Labels). The LCA methodology, described in details by the ISO 14000 series, allows the assessment of the environmental impacts due to products, processes, or services, by the identification of the input (e.g. energy and material consumption) and output (e.g. waste and pollutant production) streams exchanged by the process with the environment (i.e. from raw materials procurement to waste streams disposal). The application of LCA as tool for integration of sustainability aspects in process design and development is gaining wider acceptance and methodological development. In this study, the life cycle modeling was used to support the development of a novel tanning process based on the use of a new class of tanning agent produced from renewable resources (e.g. glucose). The experimental activity performed to investigate the technical feasibility of the innovative tanning cycle was supported by the modelling of the process using the LCA methodology in order to assess the environmental performance of the leather production cycle. Therefore, an LCA analysis was performed in order to compare the glucose-tannage process with the traditional one from an environmental point of view