Pressure-driven ultrafiltration (UF) has two structural forms: internal-pressure UF and external-pressure UF, which are widely used in industrial water purification and wastewater reuse fields.
Compared with internal-pressure UF, external-pressure UF offers stronger anti-pollution capability. It can continuously and stably supply process water even under harsh water quality conditions, thus becoming the preferred solution for pressure-driven UF technology. Currently, a large number of systems originally adopting internal-pressure UF have been gradually replaced with external-pressure UF to improve operational performance.
However, due to the structural differences between external-pressure UF and internal-pressure UF, replacement is restricted by the existing rack, pipeline, and site conditions.
The following problems often arise during replacement:
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Rack modification is required, involving on-site cutting, welding, and anti-corrosion construction. This is time-consuming, labor-intensive, and poses considerable safety hazards.
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Extensive pipeline construction is needed, requiring long time and substantial manpower. If the original pipelines have anti-corrosion treatment, the construction will damage the existing anti-corrosion layer, significantly reducing the service life of the equipment.
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To save renovation costs and time, renovation projects often reuse a large number of existing components. However, this greatly affects the rationality of the layout of membrane modules and pipelines, leading to potential operational risks.
In a power plant project in Jiangsu Province, Ochemate successfully replaced the original internal-pressure UF system with the Ochemate® OP-8080 pressure-driven UF integrated system. This practice provides a new and efficient option for the upgrading and renovation of internal-pressure UF systems in power plants.
The water purification workshop is equipped with 4 sets of UF systems, each with a net water production capacity of 125 m³/h. The original system adopted internal-pressure hollow fiber UF membranes from an imported brand. The original equipment is shown in the figure below:
After replacement with 4 sets of Ochemate® OP-8080-27 pressure-driven integrated devices, the on-site equipment is shown in the figure below:
Compared with conventional pressure-driven UF, the Ochemate® OP-8080 pressure-driven integrated device features advantages such as easy installation, fast deployment, and small footprint. The specific comparisons are as follows:
Taking this project as an example, replacing the original internal-pressure UF system with the Ochemate® OP-8080 pressure-driven integrated device not only reduces the construction content and significantly shortens the renovation cycle but also saves 60% of the footprint compared with traditional methods due to its compact design. It is particularly suitable for projects with strict site constraints during renovation. Meanwhile, the device has a neat and aesthetic appearance, making it an ideal choice for upgrading from internal-pressure UF to external-pressure UF.
