1.5–55kW Integrated Sewage Treatment Equipment , Biological Treatment Equipment for Leather Wastewater

Integrated Leather Wastewater Treatment Equipment: Used for wastewater treatment in various processes including raw hide processing, wet blue leather processing, leather dyeing, and fur processing.

Quick Details

The leather manufacturing industry generates industrial wastewater characterized by complex pollutants and high pollution loads. We provide professionally customized integrated treatment systems. The equipment is specially designed for treating tannery wastewater containing high concentrations of chromium salts, sulfides, ammonia nitrogen, salts, and refractory organic matter. Through the combined technology of physicochemical pretreatment – bioaugmentation – advanced detoxification – resource recovery, it not only ensures that wastewater stably meets the strictest discharge standards worldwide, but also commits to recovering valuable resources from wastewater, transforming the environmental compliance cost center into a circular economy profit driver.

Tannery wastewater (including mixed wastewater from liming, unhairing, tanning, dyeing and other sections) is recognized as one of the most difficult-to-treat industrial wastewaters, with its core challenges as follows:

Highly Toxic Heavy Metals: Mainly derived from chrome tanning processes, it contains high concentrations of trivalent chromium, which poses cumulative toxicity and environmental risks.

High-concentration Inorganic Pollutants: Rich in sulfides, ammonia nitrogen, chlorides and sulfates, resulting in extremely high total dissolved solids (TDS) in wastewater. It is corrosive, malodorous, and exerts strong inhibitory effects on biological treatment processes.

Refractory Organic Matter: Contains large amounts of hair degradation products (proteins), oils and fats, dyes and fatliquors, leading to extremely high COD concentrations and poor biodegradability (B/C ratio).

Extreme Fluctuations in Water Quality and Quantity: Wastewater properties vary drastically between different production sections. The mixed wastewater has highly unstable quality, imposing extremely high requirements on the shock resistance of the treatment system.

This system adopts a targeted and complete solution featuring separate chromium liquor recovery + high-efficiency sulfide removal + salt-tolerant bioaugmentation treatment + advanced nitrogen and toxin removal.

Separate Collection and Recovery of Chrome Tanning Liquor: A chromium liquor diversion system is designed to efficiently recover chromium hydroxide sludge via alkaline precipitation. After dewatering, the sludge can be reused in tanning processes or disposed of safely.

Comprehensive Wastewater Pretreatment: For mixed wastewater, catalytic oxidation (to eliminate sulfide toxicity and deodorize) combined with high-efficiency coagulation sedimentation is adopted to remove sulfides, suspended solids, partial oils and fats, and chromaticity in advance, providing stable influent conditions for subsequent processes.

Hydrolysis Acidification: A hydrolysis acidification tank is installed to convert macromolecular refractory organic matter (such as proteins and oils) into small-molecular organic matter, improving wastewater biodegradability and achieving partial nitrogen removal.

Salt-tolerant Special Microbial System: The core advantage of this system. Domesticated exclusive compound bacterial agents resistant to high TDS and toxicity are adopted, combined with A/O (Anoxic/Oxic) or SBR processes. Under optimized control, it efficiently removes COD and BOD, and initiates nitrification and denitrification processes.

Enhanced Biological Nitrogen Removal: Targeting extremely high ammonia nitrogen concentrations, a multi-stage anoxic/aerobic design or additional biological filters are adopted to ensure advanced total nitrogen removal.

Electrochemical Oxidation: An electrochemical oxidation unit is added after biological treatment as the final polishing step, which completely degrades residual non-biodegradable COD (such as dyes and fatliquors) and trace toxic substances, ensuring that effluent COD stably meets discharge standards.

Core Product Advantages

Thoroughly Addressing Chromium and Sulfide Pollution: The process design of separate chromium liquor recovery fundamentally resolves heavy metal pollution risks, meeting the stringent chromium restrictions in regulations such as the EU REACH; high-efficiency pretreatment completely eliminates sulfide toxicity and odor.

Excellent Tolerance and Treatment Capacity for High Salinity and High Ammonia Nitrogen: The core salt-tolerant microbial system breaks through the failure bottleneck of traditional biological methods in high-salinity wastewater treatment, ensuring high-efficiency and stable pollutant removal rates even in high-salinity environments.

Multiple Safety Guarantees for Stable Compliance: With the triple protection of "pretreatment + bioaugmentation + electrochemical oxidation", the system has strong shock resistance and delivers stable and reliable effluent quality.

Resource Recovery and Operational Cost Optimization: The chromium recovery system directly generates economic benefits. High-efficiency biological treatment reduces chemical reagent consumption. The high degree of system automation lowers labor costs and operational risks.

Modular Delivery and Rapid Implementation: The integrated, skid-mounted design enables flexible deployment and rapid installation & commissioning in complex factory premises, greatly shortening the project construction cycle and helping customers achieve environmental compliance quickly.

Application Scenarios

Tanneries processing various hides such as cowhide, sheepskin and pigskin

Wet-blue leather processing plants

Leather dyeing and finishing workshops

Fur processing enterprises

Centralized wastewater treatment stations in leather industrial parks

Technical Specifications of 3 T/h Integrated Biological Treatment Equipment for Leather Wastewater

Application Scope

Liming and unhairing wastewater, chrome tanning wastewater, deliming wastewater, dyeing and fatliquoring wastewater, vegetable tanning wastewater, etc.

Flow Chart of Integrated Biological Treatment System for Leather Wastewater

(Customization of treatment processes is available based on different working environments, water quality and treatment requirements)

Leather Wastewater (Classification & Separate Collection)

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Classified Pretreatment (Chromium Salt Recovery, Sulfide Removal)

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Pretreatment (Equalization Tank, Degreasing, Coagulation Sedimentation Pretreatment)

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Biological Treatment (Hydrolysis Acidification, Contact Oxidation, MBR/MBBR, Reflux System, Filter Press, etc.)

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Electrochemical Wastewater Treatment Equipment

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Discharge