Reduce emissions of liquid and solid waste in tanning. Achieve ecologically friendly or green processes and contribute to a better living environment for everyone. In addition improve the quality and yield of wet-blue and finished leather products.
The technology has been granted more than 10 domestic invention patents and 2 international patents via near 10 years research and development. With years’industrial application by our customers, the technology has proven safe, reliable, economic, efficient and stable. If widely applied in tanneries, the technology can basically solve the pollution problem of the tannery industry.
Environmentally, our technology is able to achieve meaningful reduction in the following areas:
a)Chrome based sludge by more than 70%
b)Lime based sludge by more than 80%
c)Pollutant emission by more than 70%, with almost no waste water emissions in liming,pickling and chrome tanning,
d)Water use by more than 70%
e)Land use for environmental treatment by more than 70%
f)Environmental facility costs by more than 70%
g)Chemical use for environmental treatment by more than 70%
h)Labor costs in environmental treatment by more than 50%
In product quality, our technology has demonstrated the following attributes
- Produces leather that meets all quality specifications
- Increases leather yield by 2%-5%,
- Significantly reduces wet blue wrinkles
- Increases shrinkage temperature by 2-10 ℃,
- Increases tear strength by approximately 15%,
- Reduces loose surface by more than 15%
- Increases limed hide weight by 8%-20%
- Improves hair removal process, minimizes residual hair root and increases the efficiency of hair filtering.
Total investment required is only about 3-10% of traditional environmental treatment facility spending.
Equipment needed: water pump, collection tank, connection tubes, and hair filters, particle screener.
For example, a tannery with the daily processing of 100 tons of hides consumes 30 tons of water and discharge about 25 tons of effluent to the environment if the conventional production method is applied and the tannery operates for 10 months a year. The discharged effluents contain a large amount of COD,BOD, sulfides, chromium compound and other chemicals such as kinds of acid, base, salt, grease, antiseptic, tanning agents and dyes which cause serious pollution to the environment, and the effluent treatment for environmental protection takes about 40 million RMB. However, BIOSK tannery effluent reusing technology can significantly reduce the pollution to the environment with a proper modification to the conventional tannery facilities which needs a small investment. If new tannery equipment is used, the investment is about 2 million RMB and it can drastically reduce the governmental investment and management to the environment protection.
Tannery wastewater reusing engineering seminars were organized in May 2010 and July 2011 and were attended by more than 200 people that included industry experts, professors, entrepreneur and engineers who fully acknowledged the technology.
Fujian Xingye Tannery implemented the tannery wastewater reusing technology in mass production in July 2012. During 5 years’ stable operation, the wastewater has been reused for 1500 times.
Guangdong Jiechu Tannery started to implement the technology in mass production in November 2012;
Xuzhou Xingning Tannery started to implement the technology in mass production in May 2013;
Fujian Ruisen Tannery started to implement the technology in mass production in October 2014;
Hebei Huanghuadefu Tannery started to implement the technology in mass production in November 2016;
Supported by CLIA in October 2016, we oganized “Leather clean production and tannery wastewater reusing technology seminar”attended by well-known industry experts, professors, client representatives and potential clients from all over the country. Together with the attendees, we visited Xuzhou Xingning Tannery to investgate the production and implementation of tannery wastewater reusing technology,explained their related questions and reached initial cooperation intentions in the adoption of the technology with many tanneries.
Invited by an Australian tannery in 2014, our technical team conducted the mass production trial of the wastewater reusing engineering in liming process and the result was fully acknowledged and certified by the leaders and the engineers of the tannery.
In April 2016, the leather expert Dobre Jovanoski from Macedonia visited our company to know more about the tannery wastewater reusing technology and spoke highly of it.Dobre Jovanoski published an article on Leather International to describe the technology.
In August 2016, The technical editor of World Leather magazine Richard Daniels visited our company and Fujian Xingye Tannery to investigate the application in mass production of the tannery wastewater reusing technology.According to investigation, Richard published an article on World Leather to give a full-scale report on the technology, improving its publicity in the international leather field.
In February 2017, two experts from China and UK published dissertations on BIOSK tannery wastewater reusing technology which was attached great importance on the 34th International Union of Leather technicians and chemists (IULTCS) held in India.
Since 2005, we have invested considerable amounts of human, material and financial resources in the d evelopment of our technology. We conducted numerous experiments including large, medium, and small scale. We have encountered many difficult problems, for instance, large surface wrinkles, rough grain, rot grain,mold, low penetration rate of chemical agents, bad odor in waste liquor, increased solid waste, high viscosity of reused liquor that prevents further reusing, etc. After tremendous amount of effort and tenacity, and after many original, innovative, and sometimes revolutionary changes to conventional tanning technology, the successful development of tannery wastewater reusing technology come true.
The advanced analysis equipment used in the research and development are gas chromatograph-mass spectrometer, liquid chromatograph-mass spectrometer, high performance liquid chromatograph, ion chromatography, inductive coupling ect.
七：How the Technology Works
The technology combines tanning engineering and medical theory
The main objective of waste water reusing technologies is to protect the collagen fibers from being dissolved and permit the greatest degree of opening up, which in turn provides a sufficient number of amino and carboxyl.
There are many substances such as bacteria, fungi, viruses, and some enzyme’s material in tannery effluent. In addition, the tanning process produces lipids, proteins, other degradation products and chemical compositions. For these substances, Biosk developed special agents in each of the tanning process, aimed at eliminating the negative effects of these substances and microorganisms on waste water. In the acidic environment, there are many microorganisms and enzymes that survive, similarly in an alkaline environment. Of these factors, some have both a positive and negative effect on reusing; a large number of experimental data proves that the technology is capable of inhibiting harmful factors, strengthening the favorable factors, Adding certain agents could improve shrinkage temperature of wet blue, protect grain surface from damage, and increase yield.
Just like using a soup stock to boil lamb meat, there is a natural advantage in using tanning water. The calcium and organic acid in tanning waste water can form a complex that helps break up collagen fibers moderately and evenly and keep the waste liquor stable. Reusing of waste water is accomplished by adjusting certain engineering processes and adding special chemicals that include pharmaceutical agents.
Conventional processes are adjusted for the purpose of reusing. For example:
• In liming process, a specialized filtering process is added to filter out hair as much possible.
• De-liming and bating processes are combined into one. In order to play the roles of special agents
• Pickling and chroming processes are combined into one.
2、Special agents are added.
Tanning waste liquor contain large amounts of substances that hinder reusing, such as substances that prevent collagen fibers from opening up, enzymes, microbes, and others. The special agents can either dissolve these substances, or reduce their impact on reusing, or turn them into substances that help reusing.
For example, in the liming process, if DO-PRO that contains pharmaceutical ingredients is added, it can loosen up the blood vessels, lymphatic tubes, and glands that already exist in the raw hide (see Figure 1 for an illustration). These can then act as natural passages for the OH- and Ca2+ in the liming pelt to reach deep inside the collagen fiber bundles so as to more fully and completely separate and open up the inner collagen fiber bundles. As a result, the collagen fibers open up more evenly (see right figure for an illustration). This helps overcome the problem of “tight inner and loose outer” that often occurs in tannery process and improves yield, softness, fullness and reduces loose grain.
The adjustment in process and the application of special agents help to open up collagen fibers. This is more conducive for the usage of other chemicals. It also prevents collagen fibers from being excessively degraded (see Figure below for an illustration). Another benefit of our engineering is that the solid discharge (e.g. hair and meat remnants) is no longer dissolved into the waste liquor and is instead filtered out. This makes the waste liquor easy to reuse in unlimited times.
八、 solid waste：
a. Chemicals such as sulfide and lime generate solid waste. In our engineering, we replenish the same amount of sulfide and lime into the drums as that lost when the hides are taken out. Therefore, the amount of sulfide and lime is kept constant in the waste liquor. As a result, the use of sulfide and lime as well as solid discharge is significantly reduced. Pollution by hydrogen sulfide is also reduced.
b. We also add a filtering process in the engineering and minimize the dissolution of hair and meat into the waste liquor. This reduces the amount of solid waste in waste liquor and facilitates repeated reusing. The filtered out hair and meat residue, etc. can be used for other purposes.
c. The special chemical agents we apply in the waste liquor can preserve collagen fibers and prevents them from being damaged by other chemicals. As a result, the reusing engineering generates much fewer organic substances compared with conventional engineering. The organic substances (e.g. fat and fibers) generated can also be easily removed. Some of them, float at the top of the waste liquor storage can be removed manually. Those that sink to the bottom of the storage facility can be easily removed after two to three months.
d. We find that the existence of small amount of solid waste in reused waste liquor does not affect product quality. Nor does it hinder the reusing process.
九：The flow chart of tannery wastewater reusing.
a. "Leather Preparation and Tanning Process Sealed Wastewater Reusing System" is recognized as a Science and Technology Innovation by Henan Province in May 2010.
b. "Leather Preparation and Tanning Process Sealed Wastewater Reusing System" is awarded First Prize by the Henan Environmental Protection Agency in September 2010.
c. "Sealed Wastewater Reusing System" is recognized as a key conservation technology to be promoted by the Henan Development and Reform Bureau and Environmental Protection Agency in August 2012.
d. "Award for Innovation in Energy Conservation, Emission Reduction, and Environmental Protection" by the Chinese Leather Association in September 2012.
e. Top 50 Tax Paying Enterprise in 2009.
f. "Ten Best Enterprise in Promotion of Technology in Henan Province" in 2010.
g.”The Award for Technical Invention”by China Light Industry Union in December 2015.
h.“The Excellent Participating Enterprise in Nationwide Light Industry Quality Management Team”by China Light Industry Union in 2016.
I. Included in “The Project of Water Pollution Control and Key Industry Clean Production technology Promotion”by the Ministry of Industry and Information Technology and the Ministry of Environmental Protection in August 2016;
十一：Some Approved Patents
A Tanning Engineering that Reuses Waste Water from Soaking to Dyeing.
A Tanning Engineering that Reuses Waste Water in prickling without using chrome.
A Tanning Engineering that Reuses Waste Water in production processes.
A Tanning Engineering that Reuses Waste Water in De-liming and Bating.
A Tannery Waste Water Reusing Engineering Step by Step
A Waste water reusing technology of liming or re-liming for sheep skin tanning
A Tanning Technology That Uses Waste Liquor in Pickling Tanning Process for commercially use
A Liming and Unhairing Process of Reusing of Liming Waste Liquids with Lime-free or Lime-Less
A Tanning Technology of Neutralization by Reusing the Waste Water.
A Tanning Technology of Retanning by Reusing the Waste Water
Australian and New Zealand authorized patents.