Durable and high-performing filter fabrics for the fertilizer industry

Valmet’s offering consists of filter fabrics for both phosphate rock washing and phosphoric acid production. All fabrics are developed to withstand high process temperatures, complex chemical environments, and a wide variety of slurries. With its global production network and modern equipment Valmet is ready to meet the fertilizer industry’s future growth and capable of manufacturing even the largest filter cloths.

Special features make Valmet’s filter cloths unique

Valmet’s fabrics combine high flow capacity and particle retention efficiency with durable construction – resulting in excellent mechanical and dewatering properties and improved filtration rate in phosphate rock washing. For phosphoric acid production, they provide great washing properties thanks to dirt-repellent yarn material and innovative weaving structure. 

Valmet uses modified polyester yarns to enhance the filtration properties of the cloth, special edge treatments to increase resistance against abrasion and a unique technique to strengthen the seam area.

“In addition to their outstanding filtration efficiency, our filter cloths are especially known for their long lifetime. As such, they contribute to stability and reliability of the filtration process, and thus also create savings in energy and maintenance costs,” Vishaan Parbhoo, Product Manager, Horizontal Vacuum Belt Filters & Fertilizer Industry, says.

Sustainability drives Valmet's R&D

Valmet’s filter fabrics are tailor-made for the customer’s equipment and process. Different cloth options are always tested on-site to find the application that best meets the customer’s targets.

“For further tailoring and product development we utilize our in-house laboratory or the new portable laboratory solution. For example, we analyze raw materials and finished goods, and do continuous research on used fabrics and different chemicals,” explains Sara Moreira, R&D Technician at Valmet.

The top driver in Valmet’s product development is sustainability.

“Our filter fabrics are durable and keep their promised properties throughout their lifetime – thus making them a sustainable and economical choice. Yet we strive to help our customers in taking their sustainability targets further and to improve the sustainability of our own operations. We are also continuously looking for new bio-based or recycled materials for manufacturing filter fabrics and seeking recycling options for the used cloths,” Moreira says.

Experience turns to expertise

Valmet has obtained its extensive filtration process and technology expertise through decades of research and collaboration with its customers and filter suppliers.

“We are supplying technology and services for the pulp, paper and energy industries as well as mining and chemical, food, biotechnology and pharmaceuticals industries. Our experience has given us the opportunity to learn about the filtration process in different industries, filter technology and chemicals. Based on that know-how, we collaborate with our customers to find the optimal cloth solution to match with their equipment – having the entire process in mind,” says Torsti Lähteenkorva, Senior Manager, Mining & Chemistry at Valmet.

Lähteenkorva mentions a recent successful case, where a customer contacted Valmet as they were forced to change the filter cloth only after two months due to mechanical damage. Valmet proposed another filter cloth type, and the cloth’s lifetime was extended to five months leading to significant cost savings. 

“I’m proud to say we are a lot more than just a filter cloth supplier. Sure, our long experience enables us to supply technically excellent filter fabrics, but it’s our service attitude that makes the difference. Thanks to our global service network, we are also close to the customer,” Lähteenkorva says.

Did you know?

Valmet’s Filtration Technology Center including the laboratory and a production unit is located in Ovar, Portugal. To ensure fast and reliable deliveries to customer sites around the globe, filter fabrics are additionally being produced in Tampere (Finland), Tianjin (China), Pune (India), Belo Horizonte (Brazil), and Aiken and Whintrop (South Carolina, USA).