Sustainable Water Management In Tanneries Is #1 Eco Concern

In Article8 Minutes

Month: September 2020

On the 25th September 2015 the United Nations General Assembly ratified the Sustainable Development Goals (SDGs). These 17 goals contain issues that are all intertwined and working on achieving them is the task of a generation or even more. What is notable about the SDGs is that there is one directly linked to water and our human usage of this precious resource, underlining its importance. Something the leather industry has taken to heart for years in regards to sustainable water management.

SDG 6: Clean Water and Sanitation

Ensure availability and sustainable management of water and sanitation for all.

Global water use and leather 

In the 2019 UNESCO World Water Assessment report, it’s estimated that global water demand will exceed supply by 20-30% by 2050. Compared to other estimates, that is a positive. Already 22 countries suffer serious water stress, which has a major impact on population, industry and the environment. Parts of Europe are already reaching water stress levels above acceptable norms and over 90% of natural disasters are water related. If anything, these numbers prove that change is not optional but necessary.

According to UNIDO research, water consumption per kilogram of hide is 12 to 37 liters of water. To give you an idea of comparison, for 1 kilogram of cotton around 10,000 liters are used1. It illustrates that to produce the materials we use, we need water. Of global water consumers, agriculture is the biggest user with over 69%, followed by industry (19%) and households (12%). Leather production accounts for a tiny percentage, something close to 0.02%, of total water consumption. A lot has already been done to change the impact of leather production, but still the industry will use (and recycle) water – it is one of their main resources.

Sustainable water management in tanneries

Sustainable water management is not a new focus point for the leather industry, and since the ratification of the SDGs, it’s only upped its game. Obviously, leather production can’t do without water, but we can manage the resources better and more efficiently, and also lower the impact of pollution. A number of things have already been done, many of them for several decades already:

  • Switch from running water washing to batch washing – by using a closed drum (with a more efficient design), a continuous flow is no longer necessary. Since 30-50% of the water is used in this process, savings are significant. Smart design of the drums also removes the need for intense cleaning and make it easier to remove residues.
  • Low float techniques – by reducing the amount of float (water) hides are soaked in and increasing chemical efficiency, water use can be significantly reduced. Finding the optimal method of chemical application is key, as chemical intensity can damage the hide.
  • Recycle and reuse process water – smarter drums and water treatment technologies make it possible to remove effluent and reuse and recycle of water in processes. This is already being done in most of the developed world and many tanneries in developing nations, and can lead to vast savings. Build-up of chemicals and organic content can cause risk, but modern measuring enables tanners to optimize their processes and water treatment to minimize environmental risk. We explain more of this in [article 23] here.

It needs to be said that technical innovations, like hide processors, compartmental drums and computerized monitoring systems make a lot of these innovations possible and beneficial to the process. Good housekeeping (energy efficient dryers, clean floors, no leaky valves, fleshing collection) can make another significant difference in the resource efficiency of a modern tannery.

It’s estimated that global water demand will exceed supply by 20-30% by 2050

Reducing the water footprint

Data shows that in the last 25 years, water use in leather production has declined by about 37%. The average of 60m3 of water per ton of hides (1994) is now 38m3 ton per hide (2019) and in many tanneries even lower. The industry share in the global water footprint has, therefore, decreased as well. These results show that water management is vitally important for European tanners, but more important even is the way tanneries take care of their waste materials, which are contained in the downflow of production waters. Something they have already turned into an art.

We will look further at water resourcing in the next article.

  • Buljan, J., Král, I. (2019) The framework for sustainable leather manufacture. UNIDO. Retrieved from: Leather Panel. [Accessed on 30 July 2020]
  • Gutterres, M., Aquim, P, Passos, J. Trierweiler, J. (2010) Water reuse in tannery beamhouse process. Journal of cleaner production. Vol. 18, 1545-1552. Retrieved from: IHE Delft. [Accessed on 9 July 2020]
  • Independent Group of Scientists appointed by the Secretary-General (2019) Global Sustainable Development Report 2019: The Future is Now – Science for Achieving Sustainable Development. United States, New York. Retrieved from: Sustainable Development. [Accessed on 8 July 2020]
  • Nothing To Hide (2015) Essay Ten: Water Consumption – Reducing water use in tanneries. Retrieved from: Nothing To Hide. [Accessed on 8 July 2020]
  • Sundar, V., Ramesh, R., Rao, PS, Saravanan, P., Sridharnath, B., Muralidharan, C. (2001) Water management in Leather Industry. Journal of Scientific & Industrial Research Vol. 30, June 2001. Retrieved from: JSIR. [Accessed on 9 July 2020]
  • Swartz, C., Jackson-Moss, C., Rowswell, RA., Mpofu, AB, Welz, PJ. (2017) Water and Wastewater Management in the Tanning and Leather Finishing Industry: Natsurv 10 (2nd edition) – Report to the Water Research Commission. Retrieved from: Research Gate. [Accessed on 8 July 2020]
  • WWAP (UNESCO World Water Assessment Programme). 2019. The United NationsWorld Water Development Report 2019: Leaving No One Behind. Paris, UNESCO. Retrieved from: UNESDOC. [Accessed on8 July 2020]

1One could argue that leather as a by-product is also responsible for agriculture use, which takes 20,000 liters of water to produce. For that reason a percentage of the animal rearing is allocated to leather (3.5%) according to the COTANCE Product Environmental Footprint Category Rules.

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    Better Water Stewardship And A Lower Footprint For Leather

    In Article11 Minutes

    Month: September 2020

    In previous articles, we’ve talked about the way that water management in modern tanneries aligns the UN’s Sustainable Development Goal on water. Most European tanneries had already various working methods in place that helped them reduce their water consumption. But on the whole, we can’t do without water so it’s all about how it is sourced, treated and returned.

    Blue, green or gray water?

    Water is sourced from various origins, and industrial applications very rarely use any of our drinking water. There are three types of water that can be sourced for the leather making process:

    • Blue water – clean water drawn from service providers, rivers, lakes and groundwater
    • Green water – rainwater or water collected through evaporation (not part of surface or groundwater)
    •  Gray water – water recovered from domestic use, containing mild pollutants (excluding sewage)

    Mapping the sourcing of water is important to get an idea of the water impact of production. For example, a kilogram of beef uses 15 thousand liters of water to produce. Of this, on average, 93% is green, 4% blue and 3% grey (Mekonnen & Hoekstra, 2010). Sourcing varies wildly depending on which part of the world you are in and what the locally available resources are, and that says a lot about the sustainability of practices and their overall impact on the environment and human welfare.

    Currently, there are at least 17 nations facing extreme water stress (Hofste et al, 2019) and the UN recognizes the urgency of efforts towards the water quality SDG. Yet, the SDGs form a network and efforts often have a knock-on effect. A good example are SDGs related to food production (SDG goal 2: Zero Hunger). Food production relies on agriculture and industrial processes, that need copious amounts of water. Efforts on one goal can negatively affect the other, which forms a significant challenge.

    The water footprint of leather

    Since leather is a by-product of the meat industry, the water footprint is relevant. Product category rules have determined that animal rearing and agriculture water-use should not be allocated to leather completely (here follow the leather PEFCR (Product Environmental Footprint Category Rules), which state a 3,5% allocation). Regardless, in the public eye, the water footprint of meat will be connected leather as well. But how much does the water footprint actually tell us about the sustainability of leather production?

    There’s a correlation between a tannery water footprint, carbon footprint and energy footprint though there are many influencing factors such as on-site recycling, renewables, and so on. Two tanneries could have the same water and energy consumption, but have completely different carbon footprints. Comparative research found that tanners with a high-water footprint often have a low energy footprint and vice versa (Laurenti et al, 2016). There are tanneries who manage to lower both, but it serves to indicate the complexity of environmental stewardship. Really assessing the sustainability of leather based on water usage alone is therefore risky.

    Water is sourced from various origins, and industrial applications very rarely use any of our drinking water.

    Reduce, reuse and recycle

    No drop of water is wasted in European tanneries and nothing re-enters surface water bodies without extensive purification. Most tanneries go a lot further though and water leaves their processes even cleaner than it came in or is used in circular processes. EU-wide, extensive systems monitor and reduce water consumption and continuous improvement helps reduce consumption. In Italy and other parts of the world, tanneries are clustered together and directly connected to treatment plants to complete the process of returning clean and healthy water: a textbook example of industry collaboration driven by a shared commitment to environmental sustainability.

    Below are many of the best practice adopted by modern tanneries to minimize their water footprint and protect their local water resource:

    1. They reduce water consumption with smarter processes, economic water use and integrated processes (combined process steps), with more efficient chemical use. UNIDO (2011) reports much water can be wasted, and reducing water waste also involves reducing the amount of solid waste in the water itself with filtration and waste processing solutions.
    2. They reuse water in second or even third batches to optimally use the active agents in the water. Sustainable chemical solutions can play a major part in realizing this with biodegradable and fossil/petroleum-free base materials. The more effectively chemicals bind and degrade, the easier it is to reuse or discharge wastewater.
    3. They recycle water sources by working towards closed loop systems with integrated on site filtration and effective waste disposal and processing. Reclaiming chemicals fits the same mold which many tanneries already do.

    Innovations in tanning technologies (chemical and mechanic) and water management play a major role in increasing the water footprint. The challenge is developing a tailored management system that fits a tanners’ unique mix of materials, processes and practices. Monitoring and measuring water inflow and effluent helps get a better grip on water usage. In this way, tanneries can help contribute to cleaner surface waters. Excellent purification facilities and performance make a world of difference. A few examples of innovative methods for water purification include:

    Primary treatment (effluent wastewater)

    • Gravitational settling allows heavy solids to fall out of the solution and settle at the bottom of the water as sludge, which is easily removed.
    • Skimming is the physical act of removing fats on the surface of the water, preventing them from remaining part of the effluent.
    • Secondary treatment (partly-cleaned wastewater)
    • Anaerobic digestors break down the organic content in the waste water in an absence of oxygen.
    • Chemical flocculation helps produce a sludge and make chemicals reusable without the use of biological sources.
    • Filtration is done by using a membrane and machines to remove pollutants. This is a physical means of treatment.
    • Tertiary treatment (clean water)
    • Trickle beds let the water flow over rocks covered with microbes that scrub out the pollutants.
    • Reed beds have plant roots into the wastewater stream, which are able to absorb pollutants and clean the water.

    Each tannery (or effluent treatment plant) will have a range of these technologies as well as others, selected to produce the best results for their particular requirements. The result for European Tanneries is water discharged that meets the EU Industrial Emissions Directive (often exceeding it, a source of pride for tanners). So what is next?

    The next frontier: a better water footprint

    The water footprint is currently calculated using ISO 14046. This standard only covers direct water use, where indirect water use (virtual water, that is used in indirect processes like the cattle rearing) could tell us much about the full impact of a process. Part of it is in the allocation in the PEFCR, which is a step forward for transparency. Secondly, the water footprint is directly connected to the ecological, energy and carbon footprint. An integrated, holistic approach is necessary to fully comprehend the impact of tanners, so we get the full picture and not isolated effects. That way, we can truly reduce the environmental footprint. .

    Selected source material:

    • Buljan, J., Král, I. (2019) The framework for sustainable leather manufacture (second edition). UNIDO. Retrieved from: Leather Panel. [Accessed on 30 July 2020]
    • Water Footprint Network. What is a water footprint? Retrieved from: Water Footprint. [Accessed on 8 July 2020]
    • Mekonnen, M.M., Hoekstra, A.Y. (2010) The green, blue and grey water footprint of farm animals and animal products, Value of Water Research Report Series No. 48, UNESCO-IHE, Delft, the Netherlands. Retrieved from: Water Footprint. [Accessed on 8 July 2020]
    • Mekonnen, M.M., Hoekstra, A.Y. (2012) A Global Assessment of the Water Footprint of Farm Animal Products. Retrieved from: Water Footprint. [Accessed on 8 July 2020]
    • Laurenti, R., Redwood, M., Puig, R., Frostell, B. (2016) Measuring the environmental footprint of Leather Processing Techniques. Journal of Industrial Ecology. Retrieved from: Research Gate. [Accessed on 8 July 2020]
    • Hofste, R.W., Reig, P., Schiefer, L. (2019) 17 Countries, Home to One-Quarter of the World’s Population, Face Extremely High Water Stress. World Resources Institute. Retrieved from: World Resources Institute. [Accessed on 13 July 2020]
    • UN (2020) Press Release: United Nations Launches framework to speed up progress on water and sanitation goal. Retrieved from: UN Sustainable Development. [Accessed on 13 July 2020]
    • UNIDO (2011) Introduction to the treatment of tannery effluents. Retrieved from: UNIDO. [Accessed on 13 July 2020]
    • White, C., McNeillis, P., Mathews, R., Chapagain, A., (2014) Energising the drops: Towards a holistic approach to carbon & water footprint assessment. Retrieved from: Water Footprint. [Accessed on 13 July 2020]

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      Electric Driving & Hydrogen Cars Are Changing Mobility

      In Article10 Minutes

      Month: September 2020

      Remember when an electric car was still pure sci-fi? It’s not even that long ago; in 2010 only 17,000 electric vehicles (EVs) were on the global roads. At the start of 2020 7.2 million EVs are on the road and sales are booming. Companies supply electric vehicles to their employees and install charging stations at their homes. Power grid charging points are everywhere, and the improved range and lower costs have made EVs attractive alternatives to traditional vehicles.

      Environmental legislation prompts a general push towards more sustainable forms of mobility, which is rapidly transforming the automotive industry, particularly in China and the emerging Indian market. It’s also changing how we use our cars, the way the interiors look, and the importance of interior materials like leather.

      Electric driving and changing mobility interiors

      Most EVs look like regular cars, but in new (native) electric cars effective battery placement is increasing their range. Interiors also have up to 10% more space and car interior designers are rethinking how our cars will look. Due to environmental concerns, weight reduction is key. Connectivity and modern technology take away clunky, heavy dashboards and manual controls (including the manual clutch). Touchscreens, voice control, and smart technology take over. That means more room, but also more silent travel for drivers.

      However, consumers want to feel the classic vibe of car interiors (but healthy, so VOC-free). Leather fits this idea as a luxury material in a futuristic interior. Smart surface coatings help the material remain non-squeaky, yet retain its familiar, natural look. Innovative tanning methods have already yielded very light leather materials, and leather works very well with integrated technologies. Key benefits for a new age of mobility, where other trends like autonomous driving, connectivity of mobility ecosystems, and shared mobility will converge in our car interiors. But where is the EV-revolution coming from? Let’s look into that in this article.

      Though electric cars are quiet, pedestrian safety is in question. That’s why a new EU mandate requires all e-cars to have audible ambient sound emission from 1 July 2020.

      EVs and alternative fuels

      Since the inception of mobility, the search for the best kind of fuel has been ongoing. After the introduction of the internal combustion engine, this soon turned into a search for alternative fuels that are less polluting. Did you know electric driving is not as new as we think? By the 1880s early electric cars were emerging and retained their popularity until the early 20th century. That’s where the much more powerful and efficient internal combustion engine (ICE) took over. Since then, there have been alternatives, like autogas, but up until the last couple of years ICE cars have been the norm.

      In the 1960’s, concerns about the environmental impact, new developments and likely human curiosity led to new experiments in car fuel options. The 1977 oil crisis raised concerns about the longevity of fuel availability and perhaps may have been what led to numerous launches of EVs by American and Japanese brands. A conservative car manufacturing industry was not ready to take the risk, as market viability and technological limitations made the EV an unlikely success. The legislation also hampered further development.

      Since the inception of mobility, the search for the best kind of fuel has been ongoing. After the introduction of the internal combustion engine, this soon turned into a search for alternative fuels that are less polluting

      Revenge of the Electric Car: BEV, PHEV and HEV

      Electric vehicles are on the rise and numerous types have become available in the last years. Many earlier EVs, for example, partly relied on an ICE (internal combustion engine), where today more and more full EVs are launched. This has led to a number of terms that tell you what drives the car. These are the most important ones:

      • BEV – Battery Electric Vehicle
        Fully electric driven vehicles with a battery, charged by plugging it in to the power grid.
      • PHEV – Plugged-in Hybrid Electric Vehicle
        A hybrid electric vehicle, that drives partly on a battery (charged on the power grid), but also comes with an internal combustion engine which mostly does the driving.
      • HEV – Hybrid Electric Vehicle
        Hybrid vehicle with a self-charging battery. The battery usually only supports the internal combustion engine or drives the car at low speeds. Can’t be charged on the grid.

      At the moment, the BEV is taking over the largest market share of EVs (BEV:PHEV ratio was 74:26 in 2019), making fully electric driving a reality that innovators have long since dreamed of.

      Environmental concerns and electric vehicles

      Though on the face of it, electric driving has great environmental advantages. The idea is that they use renewable energy instead of exhausting the world’s fuel resources, have no emissions, and they’re renewable. That may be true partly when ‘green’ electricity is used, but a lot of power is generated using the same fossil resources. Another point is in the batteries themselves, which use various rare mineral sources (cobalt, nickel, lithium, graphite) to be produced, incurring a carbon debt before driving their first kilometer. Sustainable sourcing is a must, and many of these resources come from unhumanitarian mining projects. While Greenhouse Gas Emissions (GHG) emissions of EVs may not be significantly lower than traditional engines, battery efficiency offers much room for innovation, where ICEs are approaching the limits of their potential.

      Hydrogen strikes back: Hydrogen driving or HFCV (Hydrogen Fuel Cell Vehicles) 

      EVs are not the only innovation in the quest for alternatives to fossil fuels. Many have for years set their hopes on a second project for mobility: hydrogen driving or fuel cell vehicles. With some questioning the level of sustainability EVs offer, hydrogen cars are stepping to the front. Fuel cells are devices that produce electricity when fed with oxygen and sustainable fuel, in this case, hydrogen (conveniently the most abundant chemical substance in the universe). Sourcing the chemical is another matter and requires quite some energy. Refueling is much faster and investment costs are much lower for hydrogen vehicles, making them half as capital intensive as EVs, according to McKinsey (2019). The big challenges: there’s no fueling network with easy access like the EV power grid. Though it was long ago, the crash of the Hindenburg still makes people nervous about hydrogen.

      Both technologies are still more expensive than traditional cars, but environmental legislation, financial benefits, and simple commonality already make EVs a convenient choice. Fuel cell technologies are compatible though, and it’s probably no sci-fi story that we’ll see an electric/hydrogen hybrid shortly.

      • Hausfather, Z. (2019) Factcheck: How electric vehicles help to tackle climate change. Carbon Brief. Retrieved from: Carbon Brief. [Accessed on 16 July 2020]
      • International Energy Agency (2020) Global EV Outlook 2020. Retrieved from: IEA Global EV Outlook. [Accessed on 16 July 2020]
      • McKinsey Quarterly (March 8, 2019) The trends transforming mobility’s future. Retrieved from: McKinsey. [Accessed on 16 July 2020]
      • United Nations Conference on Trade and Development (2020) Commodities at a glance: Special issue on strategic battery raw materials. Retrieved from: UNCTAD. [Accessed on 16 July 2020]
      • Hydrogen Council (2020) Path to Hydrogen Competitiveness. Retrieved from: Hydrogen Council. [Accessed on 16 July 2020]
      • Kasilowski, A. (2019) Hydrogen was the fuel of tomorrow, so what happened? Digital Trends. Retrieved from: Digital Trends. [Accessed on 16 July 2020]
      • European Commission (2019) Electric and hybrid cars: new rules on noise emitting to protect vulnerable road users. Retrieved from: European Commission. [Accessed on 16 July 2020]

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        Leather Is Transparency’s Next Big Target

        In Article5 Minutes

        Month: September 2020

        Full supply chain transparency sounds like a big thing and indeed it is often much more complex than it would seem at a first glance. Vogue Business writes that leather has thus far eluded the call for more industry transparency and underlines this fact with some shocking findings in third world countries where much of the fashion and upholstery leather supply chains start. It’s been a long-time struggle for the fashion industry in particular to tie all the loose ends of the supply chain together, and still parts are murky in the mists that come with a global economy.

        Yet, there is a lot of work being done in this direction, by initiatives like the UNECE Sustainable Textile and Leather Traceability project. Here the leather, textile and fashion industries are actively working together in developing futureproof methods of enhancing supply chain transparency.

        In the Vogue Business article, there is a lot to unpack and one of the most important things is that the issue at hand is the same for many industries. Though animal welfare is indeed an issue in some places of the world, the impact of supply chains goes beyond and is much more complex. Absolutely, these issues need to be addressed. It’s an enormous fallacy, though, to oversimplify the issues within material supply chains and only address that which yields shocking photographs. Leather is often criticized when it comes to environmental impact, but plastics, fabrics and other materials have their own environmental impact. More importantly, we often overlook durability and end-of-life issues when quick fixes are proposed to the issues at hand. Those ‘animal-friendly’ micro-plastics are now choking up marine life in freshwater and oceans around the world. That is also part of the supply chain.

        It’s an enormous fallacy, though, to oversimplify the issues within material supply chains and only address that which yields shocking photographs

        Vogue Business, which has previously reported positively on the ability of the leather industry to reduce its impact, relies heavily in this article on findings from Peta. The organization has mastered the art of seeking the worst industry situations and presenting these as if they are the common standards. This is, obviously incorrect. Automotive leather tanners, for example, are using leather sourced from the European meat industry. Animals which are kept under the highest standards of animal welfare in the world. Yet, buying one less leather seat will do nothing about the number of animals slaughtered. It’s for that reason the leather supply chain usually is considered to start at the slaughterhouse doors.

        When it comes to a complete supply chain, nothing is easy and the meat/dairy/leather/rendering supply chain is one of the most complex ones you’ll find. Yet, presenting one bad example and pretending it represents the whole is unfair. Peta should know, as they themselves struggle to explain some of their practices, like euthanizing thousands of animals each year. Sometimes, the solutions to our global issues are just not simple and the simple answers may create more havoc down the line.

        Yes, transparency is a major challenge for the leather industry. Automotive tanners are already working together with the meat industry to realize steps. Where it concerns the imagery that the activist organization so heavily relies on, the problem there is also more complex. The outrage consumers feel at seeing these is not reflected in the end-market industry behavior. As long as poverty-stricken regions are exploited for products at the lowest price in budget fashion, animals as well as people will suffer. Change is a supply chain-wide effort, not simply a matter of banning one by-product.

        Read the full article here.

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          Artificial Alternatives Cause Lower By-Products Prices

          In Article2 Minutes

          Month: September 2020

          Alarming sounds are coming from the New Zealand rendering industry. Often called the fifth quarter of the meat industry, rendering is the process of turning the animal by-products into materials or resources ready for use. A lot of these products we actually need or they can benefit us by replacing what would otherwise be sourced from petroleum-based resources (plastics). Think of medicine, cosmetics, confectionary (like the stuff used to make gummy bears), glues and even musical instruments. These by-products are even used in the drywall of our homes.

          Though the meat industry is thriving, rendering companies are suffering at the moment because many of their products are being replaced by alternatives following the vegan trend. But if there’s so much demand for vegan products, where are all the vegans? According to the most optimistic data the percentage of vegans in New Zealand is 2% and vegetarians account for 15%, showing an increase of 50% in the last year.

          Think of medicine, cosmetics, confectionary, glues and even musical instruments

          What is worrying is the insistence on vegan alternatives where there is no impact whatsoever on the number of animals slaughtered. If not a single rendering product would be purchased or leather product be bought, the same amount of meat would be produced as the markets are not connected directly. In fact, rendering and leather production are some of the oldest forms of recycling and give value to the concept of ‘using the whole animal’. The root of the problem here is not consumers opting for vegan in anything but what we eat (which would be the easy assumption), but insistent misguiding statements about by-products and an industry focused on making the most of this trend. And that, sadly, is how a lot of good, sustainable materials go to waste.

          Read the full article here.

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