Leather manufacturing is associated with environmental challenges, particularly water pollution and resource consumption. The traditional processes followed in tanneries often result in the discharge of wastewater containing hazardous chemicals such as sulphides and chromium, which can pose significant risks to the environment and public health.
Recognising these challenges, CSIR-Central Leather Research Institute (CSIR-CLRI), Chennai, has been at the forefront of promoting cleaner technologies that mitigate these risks and enhance the overall efficiency of leather production. CSIR-CLRI’s initiatives aim to create a more resilient and environmentally responsible leather sector by reducing water consumption and minimising pollution to enhance resource efficiency. By collaborating with industry stakeholders, governmental organisations and international bodies, CLRI strives to ensure that the leather industry can thrive in a way that is both economically viable and environmentally sustainable.
In line with this commitment, CLRI recently successfully demonstrated cutting-edge cleaner technology solutions in the Jajmau Leather Cluster, Kanpur, from 12 to 17 August 2024. This initiative, funded by the World Wide Fund (WWF-India), marks a significant milestone in CLRI’s efforts to reduce the environmental impact of leather production and promote sustainable practices across the industry.
The key technologies showcased are enzyme-based unhairing process, reuse of liming wastewater and Direct Chrome Liquor Recycling (DCLR). Through these measures (a) sulphide can be eliminated, (b) liming wastewater is not discharged, and (c) chromium in the wastewater is repurposed.
The enzyme-assisted unhairing process is a cleaner approach that replaces the conventional use of toxic chemicals with natural enzymes. Traditional unhairing methods typically rely on sulphides, which can lead to the generation of toxic waste, H2S emission and increased environmental pollution. In contrast, the enzymatic method significantly reduces the presence of sulphides in the wastewater, thereby minimising the environmental footprint of the leather manufacturing process. This method is not only safer for the environment but also improves the quality of the leather, making it a more desirable option for manufacturers and consumers alike.
DCLR is another sustainable, cleaner measure that was demonstrated. Chromium salts, used in the tanning process, are essential for producing high-quality leather but are also a major source of pollution when not properly managed. The DCLR process enables the reuse of chromium from the tanning liquor, completely averting the chromium discharged into the environment. This recycling approach curbs pollution and conserves valuable resources in the wastewater, making it a cost-effective and sustainable solution for the leather industry.
One of the most significant benefits of these cleaner technologies is their potential to reduce the water footprint of leather manufacturing. The traditional tanning process is notoriously water-intensive, with large volumes of water required for various stages of production. The bio-based enzymatic unhairing process can lead to substantial water savings by eliminating the need for high water consumption associated with chemical unhairing. Similarly, the DCLR technology reduces the need for fresh water in the chrome tanning process by enabling the reuse of chrome liquor, further conserving water resources.
The demonstration was attended by the team from WWF-India, as well as the tanners of the cluster. Dr Sundarapandiyan, Senior Scientist, CSIR-CLRI, along with the team from RC-Kanpur of CSIR-CLRI, conducted the demonstration.
The demonstration showcased the innovative technologies and fostered a deeper understanding among industry participants of the significant environmental and economic benefits these technologies can offer. The local tanners and industry representatives were highly engaged, expressing enthusiasm about the potential of the bio-based enzymatic unhairing process and DCLR to transform their operations.
The tanners noted the impressive reduction in pollutants and water usage, recognising how these innovations could lead to cost savings and compliance with increasingly stringent environmental regulations. The positive feedback from the industry was a clear indication of the readiness and willingness to adopt these sustainable practices.
Moreover, the industry stakeholders appreciated the collaborative approach of CLRI, which provided them with the necessary technical support and expertise to implement these technologies. The demonstration reinforced the importance of continuous innovation and partnership in driving sustainability in the leather industry.
