Category: Vegetable tanning

Content published by: Leather International

Over the years, the industrial activity of leather tanning has been criticised for its contribution to environmental pollution, particularly when it comes to the contamination of water bodies. Tanneries consume large amounts of water that is used with strongly alkaline and highly acidic mixtures, chromium salts and sulphides in the tanning process, so the potential for toxic substances to leak into rivers has drawn the eye of industry critics.

The treatment of hides involves many aqueous steps with discontinuous discharges, generating high volumes of effluents that require costly and time-consuming treatment to satisfy emission standards laid down by national and international legislation.

Furthermore, the amount of water used in the tanning process has also drawn criticism. Water is, after all, a precious resource and, in some parts of the world, a scarce commodity. Consequently, industry players have a shared obligation not to take the availability of clean water for granted.

Although the industry has made great efforts to reduce water consumption and prevent the discharge of harmful effluents into the water supply, its image is still tarnished in the eyes of some observers by its past failures to manage water usage in an sustainable manner. Now, it is time for public perception to catch up with how the industry is changing.

A footprint in the water

In a tannery, the many phases of conditioning and preparing the hide for tanning, as well as the transportation and fixation of tanning substances, require water. The beamhouse process where hides are made ready for tanning is, by far, the most intense process in terms of water usage. A 2019 study found that during the beamhouse process, between 7m3 and 25m3 of water is used per tonne of hides, and between 1m3 and 3m3 is used in the tanning process.

In most instances, fresh water is used for the diffusion of chemical products and the extraction of undesirable materials from the hide. The result is a significant drain on local fresh water resources. The industry’s water footprint is large, even if one disregards the water used in the raising of cattle. It is estimated that worldwide water consumption in the leather industry is around 400 billion litres annually.

If the industry is serious about improving resource efficiency, both for reasons of environmental management and cost reduction, then water use must be near the top of the list of priorities.

A tannery’s water footprint is the total amount of direct and indirect water use involved in its processes. It comprises many different elements, starting with the blue water footprint, which represents the amount of surface water and groundwater required by the tannery. Next, there is the green water footprint, which is the amount of rainwater required, and then the grey water footprint, which represents the amount of freshwater required to mix and dilute pollutants enough to maintain water quality according to certain standards.

Once measured, all of these factors can be managed. It is incumbent on the industry to apply best practice technologies and implement effective water management techniques, but this can only be done effectively when the scale and detail of the problem are fully understood.

Indeed, a 2019 paper in the Journal of Environmental Management, entitled ‘Water reuse: An alternative to minimise the environmental impact on the leather industry’, highlighted some of the systems that can help tanneries reduce the amount of wastewater they produce that contains high concentrations of contaminants and reduce the total amount of water used in the tanning process.

Among these, the overriding concept is the reuse of wastewater. The key concern is the release of the pollutant chromium into the environment, and reuse tests on both pilot schemes and an industrial scale have shown that reuse techniques, when properly evaluated, can both reduce water demand and minimise the disposal of the wastewater with chromium.

Reduce, recycle, reuse

For some tanners, the results of an intense focus on water usage and contamination have yielded impressive results and fostered innovative approaches to resource use. Among them is ECCO Leather, which operates four tanneries and two beamhouses, as well as wastewater treatment facilities in all of its tanneries to ensure that we release only clean water back into the environment.

As one of the steps in the tanning process, ECCO has developed DriTan, which uses the moisture already present in the hides. With results that are indistinguishable from traditionally tanned leather in terms of quality, characteristics, stability and lead-time, DriTan results in major savings on water, while considerably minimising the discharge of wastewater and the use of chemicals.

At its tannery in the Netherlands alone, ECCO is set to eliminate 600t of sludge per year from its effluent, which translates into 40 truckloads of sludge deposited in landfills per year.

Will tanning eliminate water for good?

ECCO sees DriTan as the first real step towards water-free leather manufacturing. The history of leather tanning goes back around 10,000 years and the process has always involved water, so it may seem inconceivable to some that water-free tanning could be possible. Nevertheless, technologies are emerging that could break the paradigm and revolutionise the industry to the point where we can now seriously ask whether there will one day be a way to tan leather without the use of water.

DriTan only impacts one step of the process, though the company’s vision is to achieve entirely waterless tanning. For that, much more innovation will be required and many stakeholders in the leather making process will need to work together. If they do, the implications of water reduction – or, ultimately, elimination – will also be felt in other key areas of the sustainability agenda.

Using less water results in lower energy costs and creates a tanning process that requires less expenditure on chemicals. Different aspects of sustainability work together to create savings. Nevertheless, transitioning to new systems and processes does come at a cost.

The total water footprint of the leather industry may seem inconsequential compared to an industry such as hydroelectric power, but leather tanning is one of the most water-intensive industries in the world, relative to its size, and critics will always point to the amount of wastewater it produces, often with a heavy pollutant load. Around 95% of the water used by leather producers is subsequently discharged and forwarded for purification, with the remaining 5% evaporating during the production process.

Increasingly stringent environmental legislation around the world will force the industry to look at water usage, particularly from the point of view of contaminants in wastewater, so tanneries will need to start considering the technologies that are emerging to reduce water usage and improve water management. The solutions are there, but they come at a cost. So, the industry will need to look beyond the upfront costs and towards the savings that can be made further down the line.

You can read the original content HERE.

Original content posted by: ONE4LEATHER.

The leather industry has, for decades, been at the forefront of innovation in sustainable technologies. It has helped manufacturers reduce their carbon footprint, but also produce leathers that are eco-friendlier produced and free of VOCs. Yet, the public image of tanneries is often very different.

When you think of a leather tannery, you are likely to have an image in your mind of an open pit filled with liquid. Hides are hanging from racks around these as workers in shorts and t-shirts handle the substances used to produce leather. And that’s as far from the truth as it gets in how leather today is produced in safe, state-of-the-art facilities, yet for unclear reasons, media reports keep featuring pictures of tourist attractions or third-world facilities. Let’s see what a modern tannery looks like.

Watch the animation below:

Especially today, with growing meat consumption and a limited availability of resources, reusing materials we have in a safe and controlled manner, is vital. Animal hide are leftover in abundance and modern tanneries turn this by-product into quality leathers with minimal impact.

You can read the original post HERE.

Content posted by: Leather Naturally.

Leather Naturally recently published an article asking “Is leather sustainable?” and tries to answer the question.

In their opinion, the answer is clear: yes. If sustainable means converting materials that would be otherwise thrown away to make the products we use to live, keeping things for a long time, repairing them when we need to, passing them on to someone else to use after us and, eventually, recycling the product as many times as possible. Leather is most certainly sustainable.

And the leather industry is also an excellent example of the circular economy, as set out by the European Commission in December 2019, its sustainable consumption and production support the United Nations’ Sustainable Development Goals.

Leather’s durability, longevity and recyclability as a natural product are underpinned by regulations and quality standards in many countries to ensure that sustainability credentials are met and maintained throughout its production.

Responsible tanneries are also very transparent about their compliance data and openly share the following areas of information with their customers: how they comply with environmental controls, how they manage wastewater and other waste, how they use and manage chemicals including restricted substances, how tanneries keep their leather workers safe, how they calculate how much energy and water they use and how customers can track a leather supply chain.

Tanneries like Splenda Leather are firmly committed to these principles of responsibility, sustainability and transparency. We are very sure that the tanning industry has come a long way in recent years and, with everyone’s commitment, we hope that in a few more years we will be appreciated as a benchmark of a sustainable productive sector worldwide.

You can read the original content HERE.

Content posted by: Lederpiel.

A residue from the extraction of olive oil called bagasse contains tannins that allow the leather to tan naturally, reducing the use of chemicals in the process. This is confirmed by a recent investigation by the A3 Leather Innovation Center Chair, of the Igualada-UdL University Campus, specialized in the leather production chain. The Olipo Project will facilitate the production of leather goods that are more ecological and free of contaminants such as chromium.

This research not only makes the leather industry more sustainable but also contributes to highlighting a residue from the oil extraction industry. According to the director of A3 Leather Innovation Center, Anna Bacardit, the use of bagasse “allows us to obtain top quality ecological leather, while revaluing a problematic waste from the olive oil extraction industry”.

Of the total material that is provided for olive production, only 20 percent is the final squeezed product and the remaining 80 percent is bagasse, that is, the remains of husk, bones and other residues of the raw material. Thus, the Olipo Project proposes new strategies within the framework of the circular economy, establishing synergies between the two industries.

You can read the original article HERE

Content posted by: Lederpiel

More than 17 million tonnes of animal elements, derived from leather tanning, are processed every year across Europe, producing just under 3 million tonnes of animal fat.

Part of all this fat is solely destined for disposal in landfills or incineration, which is a problem for both the climate and the environment as it may contain harmful substances.

To give a new life to this element, the new Life Superbiodiesel project offers an alternative for the recovery of these wastes and aims to develop, test and demonstrate the production of biodiesel from animal waste using a new fat transesterification technology.

The Technological Institute AIJU coordinates this project that aims to design, build and optimize a pilot plant capable of processing five tons of biodiesel obtained from animal fat. One of the advantages of this project, in addition to the production of high added value biodiesel, is the potential reduction of 80 percent of the carbon footprint over conventional diesels and 35 percent compared to first generation biodiesel, according to first estimates.

You can read the original information HERE.