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UNIDO has prepared and published over one hundred publications, papers, manuals and guidelines, primarily aimed at technical experts and policy makers in developing countries, though many are used by sector-related institutions and development organizations elsewhere.

The website www.leatherpanel.org is intended to provide an easy access to information sources on the leather, footwear and leather products industry, as well as to UNIDO publications related to the leather sector in one place, including earlier publications that were previously only available in hard copy.

Processing of one tonne of raw hides results in approximately 100 kg of wetblue shavings, the utilization and/or safe disposal of which is globally a serious challenge. Currently a part of the chrome shavings is used in the manufacture of leather board by combining with shavings of vegetable tanned leather. There have been also other methods tested and used to convert shavings into sellable product, e.g. application in paper, wood and other industries.

The method described in this report is enzymatic digestion.

Conversion of chrome shavings into usable products employing the technique of enzymatic digestion as developed in the United States of America and already implemented in a 3 tonnes/day commercial plant in the Czech Republic. Three products, namely, gelatable protein, protein hydrolyzate and filter cake are obtained from enzymatic digestion of chrome shavings. While the products obtained find use in construction and plywood industry and also as nitrogenous fertilizer, the chrome-containing filter cake can be used as a reducing agent in the preparation of basic chromium sulphate.

The method was successfully demonstrated at pilot scale in India using wooden tanning drums.

Generally 35-60% of the total solids in tannery sludge is organic matter. A number of solutions for utilization and/or safe disposal of tannery sludge have been proposed, practiced, tested and applied at pilot and industrial scale. Composting is one of these options and this report describes results of tests and application of sludge composting on low, non-mechanized scale together with its utilization as soil conditioner for nonedible plants.

The globalization of the leather industry means that all tanners face the same problems of minimizing the environmental impact of processing and selling into the global market. Regulatory pressures oblige tanners to make continuous improvements in the processing operations. The authorities concerned and consumers look more closely whether hazardous substances such as certain preservatives, some azo dyes and Cr(VI) are present in leather and leather products. The presence of potentially harmful substances attract attention of public media with the risk of developing unfavorable perception about health safety of leather products. In that context materials imported from developing countries are especially critically judged in some reports. Closer monitoring of this aspect has revealed that leather and leather products sometimes contain some hazardous substances like Cr(VI) although only chromium compounds in the form of Cr(III) were used in the tanning process. It has been concluded that this might be result of some undesired reactions in leather itself but the cause was unclear. In this paper, in a very brief form, some results of the investigations about conditions conducive to or inhibiting generation of Cr(VI) in leather are summarized. Also, the results of a series of tests carried out on leathers received from several countries included in UNIDO Regional Programme of Pollution Control in the Tanning Industry in South-East Asia are presented.

Utilization or safe disposal of sludge generated by tannery effluent treatment plants poses a challenge worldwide; landfill disposal should be considered only in case when no other viable option is possible.  Unfortunately, in some areas and/or developing countries properly designed and constructed landfills are not available either.
With the technical assistance of UNIDO, CETP-Ranitec in Ranipet, Tamil Nadu, India, established a low cost pilot scale demonstration landfill in October 1997, the first of its kind in the region. The report describes requirements for a safe landfill disposal and practical recommendations for replication.

In a number of these countries, particularly the least developed countries amongst them, raw hides and skins are among a very few national resources they possess. However, tanning and leather products industries have not received the very high priority they deserve in the national economy. Almost all the national governments concerned have exerted great efforts and spent much capital to build up leather industries; in some cases successfully, but unfortunately often with very unsatisfactory results. Paper prepared for the 3rd UNIDO Leather Panel in 1979 highlights some of the problems.

Typically only a small part of fleshings is used for manufacture of glue and animal protein while the major part is dumped as waste at landfill or disposed of along with other solid wastes. The unutilised fleshings, containing high concentration of lime and sulfide, putrefy and produce obnoxious odour. They also cause groundwater pollution, attract flies, rodents and stray dogs and thus represent a public nuisance. Due to high moisture content handling and transportation of fleshings is quite difficult. On the other hand, one tonne of wet fleshing with 85% moisture is estimated to generate 20-30 m3 of biogas. To solve the disposal problem of fleshings, one of the options considered and tested during UNIDO Regional Programme in South-East Asia was biomethanation. The results of testing at the pilot plant, the first of its kind in the region, are given in this report.

With increasing pressure from the pollution control authorities, tanners in many countries of South East Asia region are faced with the urgent task of utilization or safe disposal of solid wastes from tanneries, particularly fleshings. Likewise, sludge generated by tannery effluent treatment plants has to be either put to use or safely disposed. These two issues were highlighted by the industry and government representatives of countries participating in the Regional programme for South-East Asia.

The report contains details of the large scale pilot project implemented under Programme, characteristics of fleshings and sludge charged to the digestors, volume of gas generated vis-à-vis projection, coping with the hydrogen sulphide gas (H2S) and the many valuable lessons learnt. Details of the problems encountered – both process-related and mechanical – have been narrated. At the time of the report preparation (2002) it was the only operational plant of its kind in the world

Industrial sectors, especially the leather-based industry subsector in many developing countries and in former centrally planned economy countries (countries in transition), often suffer from unrecognized common interests among competing entrepreneurs. In these countries joining hands, lobbying together against governments tending to take too quick (legislative) action without foreseeing problems which might later arise in the industry, combining efforts in export promotion and retaining raw material (hides and skins) resources are of prime importance. Formulating and/or strengthening respective trade association is one of the most efficient (and fairly inexpensive) ways of tackling these problems. Recognizing the importance of professional associations and the lack of available information on this subject, UNIDO decided to conduct a survey revealing the main functions, modus operandi, managing and financing of trade associations in the leather, footwear and other products industries worldwide. The major objective of the study is not to present a model to be followed, but rather to show good practices which lead to more-or-less stable legal and economic conditions for leather-related manufacturing businesses. This paper presents problems of existing trade associations, lessons learned, possible ways of operation and relations with local and international authorities. Each chapter is followed with a list of best practices which can orient those involved in creating or operating national, regional or even international associations in the leather-based industries. The executive summary consists of a brief introduction which is followed by a full list of the best practices that have been identified. There are some recommendations offered for new and existing associations which may be considered when management decisions are made regarding future activities.

This paper prepared in 2007 for the 16th session of UNIDO Leather Panel analyzes the prevailing situation of the African leather and leather products sector in the context of the global leather-based industry. It attempts to identify and highlight the key issues regarding raw material/hides and skins production, quality and trade. Important aspects of processing of hides and skins to semi-processed and finished leathers including marketing are considered. 

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