In the nickel leaching process, 20,000 liters of nickel-containing residue slurry are produced daily, with a stable solid content of 15% (i.e., 3,000 liters of solid residue need to be separated daily), and the residue contains trace amounts of acidic components (pH value 5.2-5.8).

  Based on the production rhythm and environmental protection requirements, the customer has clearly defined three core demands:

  Processing efficiency compliance: Filtration is carried out twice a day at fixed times (once in the morning shift and once in the evening shift), with a single processing capacity of up to 10,000L to prevent residue accumulation that could affect production continuity. ?

 Thorough solid-liquid separation: The filtrate after filtration must meet the workshop reuse standards (solid suspended matter ≤10mg/L), and the moisture content of the filter cake must be less than 45%, facilitating subsequent hazardous waste disposal or resource utilization. ?

 The equipment has strong adaptability: It needs to adapt to the corrosive environment of acidic residues and meet the EU CE certification standards. At the same time, it is required that the single filtration cycle (including feeding, pressing, and cake unloading) be controlled within 2 hours. ?

 Previously, the customer used traditional plate and frame filter presses, which had three major pain points: First, the single processing capacity was only 6000L, and it was necessary to filter 3 to 4 times a day, which occupied a large amount of labor. Second, the moisture content of the filter cake is as high as 65%, and the transportation cost of hazardous waste (charged by weight) remains high. Thirdly, the filter plates have poor corrosion resistance and need to be replaced on average every three months, with operation and maintenance costs exceeding the budget by 20%. ?

 In response to the customer's demands and pain points, our technical team, taking into account the characteristics of nickel leaching residue such as "high solid content, slightly acidic, and high processing efficiency requirements", ultimately decided to choose a fully automatic diaphragm filter press with 1250-size filter plates and a filtration area of 200 square meters.

 A filtration area of 200 square meters corresponds to 75 1250 type filter plates, with a total filter chamber volume of 3427 liters. After optimizing the feeding process (simultaneous feeding through dual feeding ports to reduce feeding dead corners), the actual single processing capacity reaches 11423 liters. The filter plates are made of reinforced polypropylene (PP) material and modified with acid corrosion resistance. Resistant to acidic and alkaline environments with a pH value ranging from 4 to 10. The equipment has passed the EU CE certification and is equipped with a Siemens PLC control system, which automatically adjusts the feeding speed, pressing pressure and time. The single filtration cycle is stable at 2 hours (including cake unloading), meeting the rhythm requirement of "twice a day".

 The split diaphragm pressing system is adopted, which can achieve a three-stage operation of "feeding filtration (0.6MPa) → diaphragm pressing (1.2MPa) → air blowing drying (0.8MPa)". Considering the characteristics of fine particles and high viscosity of nickel residue, the moisture content of the filter cake is significantly reduced by combining high-pressure pressing with hot air drying.