Until now, recycled denim concept was an unsolved puzzle as recycled fabrics have been dyed by virgin Sulphur black dyestuff. Actually, there were no fully recycled denim in the market.
The good news is, MKS DevO is the world’s first company to produce a totally ecological, 100% recyclable, and sulfide-free, Sulphur Black Dyestuff, Sultan Black Recycle®.
Today, around 240,000 Tons of Sulphur Black Dye is used in the production of approximately 4 Billion pieces of Blue Jeans globally. This produces 180 million cubic meters of wastewater, enough to pollute a natural resource as big as Hazar Sea. Denim fabric producers and retailers are struggling every day to manage this desperate story.
The good news is, MKS DevO is the world’s first company to produce a totally ecological, fully recyclable, and sulfide-free, Sulphur Black Dyestuff, Sultan Black Recycle®, with recycled content which is also recyclable.
After Dyeing with Conventional Sulphur Dyes
By the reduction of sulphide ions Sulphur Black will be the form of solubilize in water so can apply to the Cotton fabric. After that for fixation it should be transfer to the non-soluble form again So Air Oxidation is the way of air passages continuous dyeing machine finally.
What is happening ?
Reaction of Sodium Sulphide with Water and Oxygen. The result is Sodium Thiosulfate.
2Na2S + 2O2 + H2O → Na2S2O3 + 2NaOH
If everything goes well and fully Oxidized;
Waste water plant should acidify before bio treatment of waste water from dyeing houses therefore pH about 11-14.
Na2S2O3 + 2HCl → S + 2NaCl + SO2 + H2S
If everything goes well you will have elementer Sulphur and sulphurdioxide. You will filter Sulphur why it is not soluble in the water but have to have scrubber for SO2 which is non permited discharge gas to atmosphere.
After air oxidation washing chambers will take all non oxidized reducing agents from cotton to the water with running meters enriched and finally deliver to waste water plant. High alkaline water before biologically treatment is required for pH adjustment. Even though reduce pH with inorganic acid like sulphuric or hydrochloric acids. So the expected reaction will be like that;
Na2S(liquid) + 2HCl(liquid) → H2S(gas) + 2NaCl(liquid)
H2S gas is a very dangerous gas. It brings; damage to eyes over 500 ppm (30 minutes), lung injury, knockdown and death (4-8 hours).
SULTAN BLACK ECO (Non-Sulphide Sulphur Black Dye)
Waste water produced by Sultan Black Eco
- It can be easy acidified without the risk of H2S emission and after filtration.
- Completely colorless, harmless to the environment and human health, easy to treat, recyclable for reuse.
- The dye lost during the washing process is also recycled for reuse.
We proudly announce to brands, buyers, dyers, researchers and all parties of who cares about sustainable production and save the planet approaches.
- Totally ecological dyeing system;
- No need to change any production method;
- No need to have new machine investment;
- No need to be suspected anymore by the environmental authority;
- No more bed odors from waste water plant;
- No more facet circle of Sulphur.
Usage amounts will be very similar even same gr/I of conventional dyes.
- Sulphide-free dye Sultan Black Eco® is taken.
- The same dyeing processes are applied as traditional dyeing.
- The waste generated after dyeing is collected.
- The collected dyeing waste with Regain acid lowered Ph to 4,5 - 5 and Sultan Black Regain® is obtained by passing the disintegrated dye through the filter press.
- Moisture in Sultan Black Regain® is removed and sent to MKS DevO facilities. In the facility, Sultan Black Recycle® is obtained.
Sultan Black Recycle® is certified from SCS Global Service* that it is made with 100% Post-Consumer Recycled Sulphide-Free Dye Content.
* SCS Global Services is an American, globally recognized, third-party certifier of recycled projects. SCS Global Services has been a global leader in environmental and sustainability verification, certification, auditing and testing for more than three decades.
We share our SCS Global Green Products link.
Why should we use SULTAN BLACK ECO / RECYCLE ?
- Sustainable / Recycled Denim
- MKS DevO shares Free Labelling from SCS Global for every meter
- Reducing waste water pollution in the production unit
- 1 kg dye production - 1 kg water consumption
The amount of waste water occurred during production of 240 thousand tonnes of sulphur black dyestuff is around 15 million cubic meters in 1 year. Example for every year size of Como Lake can be highly polluted by the amount of waste water.
While this is the case, 1 kg of water is consumed to produce 1 kg of Sultan Black Eco-Recycle dye at the MKS DevO production facility.
Let’s think ?
If all the sulfur dyes consumed in the past 1 year were Sultan Black Eco / Recycle, our savings in the amount of water used to produce these dyes would be equal to the amount of domestic water consumption that the Venice city population would consume for 1 year. Can you imagine that?
The better future with MKS DevO Chemicals.
For additional information, please contact MKS DevO Chemicals.
Denim Technical Manager