Water Saving Process Without Sulphur, Lime Depilation And Tanning Preparation Section

Research objectives

Development of sulphide free and lime depilation technology to reduce pollution in tanning process

Developing the water-saving process of tannery preparation section, simplifying the technological process, and significantly reducing the water consumption.

Task requirement analysis

The hair removal process in the traditional leather preparation section is the root cause of S2- and lime pollution.

The water consumption of leather preparation section accounts for 60-70% of the whole production process.

COD, SS and ammonia emissions account for 60%-90% of the whole leather making process.

The completion of this task can fundamentally change the current situation of tanning pollution and high water consumption.

Relevant technology status at home and abroad

SIROLIME wool free hair removal technology can avoid hair dissolution, reduce COD by about 60%, and reduce the amount of sodium sulfide 50%

The recycling technology of hair removal and ash recovery waste liquor can reduce the discharge of waste liquid and pollutants by 70-80%, but the number of cycles should not be greater than 10 times. Low sulfur enzymatic depilation technology can reduce the dosage of sodium sulfide. 50%, because the technology has not been completely abolished and the amount of lime can not be reduced, the water saving technology can not be formed.

Research and development contents

Developing raw material skin soaking technology with multiple enzymes to create conditions for no sulfides, lime, hair removal and dispersion of collagen fibers.

Development of biological hair removal technology for hair removal and hair removal

Development of enzyme preparation + hydrogen bond destruction agent instead of lime dispersion fiber technology

On the basis of sulphur free depilation process, we should save lime, ammonium salt, softening and multiple washing processes to form water-saving technology in the preparation section of leather making.

Possible results

Pigskin leather making can achieve zero use and zero emission of sulphide, and lime usage and emissions will be reduced by 70-100%

The use of cowhide leather sulfides was reduced by 70-100%; lime use and emissions decreased by 70-100%

The preparation section avoids ash removal, deashing and multiple washing processes.

Water consumption and wastewater discharge in preparation section are reduced by 30-35%

COD, SS and TS reduce 30-40%