Management of water-use in tanneries
About this essay
Jutta Knoedler is general manager of I-T-G Environmental Technology, a consultancy group in Germany. She has been auditing tanneries on environmental aspects since 1991 and continues as a globally respected authority today. She carries out audits as part of the Leather Working Group (LWG) and for Energy Controlled Leather (ECO2L). Since 1993 she has carried out research projects for the European Union, German Federal Ministry for Environment, the German Leather Association and the Research Association for Leather. She has received awards for ground-breaking technical and scientific work for waste management in tanneries (from VGCT, the German association of leather chemists), for improving energy efficiency (Deutsche Energie-Agentur, the German Energy Agency) and for energy conservation and pollution reduction in tanneries (from the China Leather Industry Association).
This essay tackles the following misrepresentations:
Myth: Tanneries are indiscriminate users of water.
Fact: The industry has reduced water use by 37% in the past 25 years.
Myth: Tanneries do not care about the volumes or cleanliness of water they use.
Fact: ‘Reduce, reuse, recycle’ is a widely adopted strategy.
Myth: Tanneries are heavy polluters of water.
Fact: The vast majority are required by law, at national or local levels, to connect to effluent treatment plants.
Considerable efforts have been undertaken by the tanning industry in recent years to obtain a better understanding of its own water footprint through collection, evaluation and benchmarking of water consumption data. Recent data (2007-2013) shows vast improvements have already taken place. On a global scale, water consumption for the production of leather from bovine hides has declined by about 37% in the past 25 years: from approximately 60 cubic-metres per tonne of hides, to 38 cubic-metres per tonne. When we include sheepskin, the industry’s share of global water use has declined from 0.02% to 0.015% and from 0.11% to 0.075% in terms of industrial water consumption.
Tanneries adhere to legal requirements or recommendations on water usage and the vast majority are working hard to cut use for several reasons, including their own quests for sustainable production, customer demands and cost effectiveness. Across the world, new legislation that requires tanneries either to operate their own effluent plants or, if they are in clusters, connect to common treatment facilities is in force or coming into force. Water purification systems, such as reed-bed technology, are in use in many facilities to help clean output in a cost-effective way.
This article outlines how the ‘reduce, reuse, recycle’ philosophy is being adopted for many reasons and with excellent results, with machinery and chemical companies launching innovations on a regular basis to help tanners adhere to their goals.