A membrane filter press is usually decided long before the purchase order is raised — in the moment a buyer confirms that one specific model can carry one specific duty. The XMAG membrane filter press series from DAZHANG Filter Press, running from XMAG30/870-UKB to XMAG1000/2000-UKB, is a practical illustration of why that confirmation takes more than reading a catalogue. The same series covers 30 to 1000 m² of filter area and 870 to 2000 mm plate sizes, and every project has to locate itself somewhere inside that envelope.

Henan Dazhang Filtration Equipment Co., Ltd. (DAZHANG Filter Press) is a filtration and solid–liquid separation equipment manufacturer founded in 2004 and based in Yuzhou, Henan Province, China. Its portfolio includes membrane filter presses, chamber filter presses, plate and frame filter presses, high-pressure round plate presses, filter plates, filter cloths, hydraulic systems and automatic washing systems, and the company states that its products and services reach more than 100 countries across Asia, Europe, North America, South America, Africa and the Middle East. The XMAG series sits inside that portfolio as an automatic membrane platform for dewatering duties in wastewater, mining, chemical, food, pharmaceutical and metallurgy applications.

Manufacturing base of Henan Dazhang Filtration Equipment Co., Ltd. in Yuzhou, Henan Province, where filter presses and filter plates are produced.

Why Model Decoding Decides Membrane Filter Press Projects

Two presses can both be described as "automatic membrane filter presses" and still be unsuitable for each other's duty. A 30 m² unit with 870 mm plates and a 1000 m² unit with 2000 mm plates belong to the same commercial series but to completely different process scales, floor areas and maintenance routines. When procurement teams compare quotations without decoding the model code first, the comparison usually collapses into price per unit instead of cost per tonne of dry solids handled.

The second common gap is pressure. Buyers frequently treat "high pressure" as a product label rather than a defined figure. In practice, three separate pressures exist in a membrane press project: the feed pressure that pushes slurry into the chambers, the membrane squeezing pressure that inflates the membrane against the formed cake, and the maximum clamping or structural rating of the frame that holds the plate stack together. In the XMAG series documentation, feed pressure is listed at 0.6–2.0 MPa and squeezing pressure at 1.6 MPa. Across Dazhang's wider range of automatic membrane and chamber filter presses, filtration pressure is specified from 0.6 MPa up to 4.0 MPa. These are not interchangeable numbers, and the first procurement question should be which one a quotation is quoting.

The practical goal at the decision stage is therefore not the largest press available. It is the smallest press that reliably meets the duty, with the pressure rating, plate material and automation scope that the actual slurry requires.

The XMAG Series Envelope at a Glance

The published specification for the XMAG series defines a clear operating envelope. Everything a buyer needs in order to start narrowing the selection is contained in these values.

Reading Plate Size and Filter Area Together

Filter area is a duty parameter. Plate size is a geometry parameter. Confusing them is the most frequent source of mis-sizing, because the two are independent: one project may need 200 m² distributed over 1500 mm plates, while another may need a similar area distributed over a larger number of smaller plates.

Filter area is the sum of the filtration surfaces of all chambers in the stack, so it is the number that must answer the throughput question: how much slurry has to be processed per batch, how many batches are possible per working day, and what cake mass leaves the press each cycle. Plate size, in contrast, describes how many chambers are needed to reach that area, how large each cake is, how heavy the moving plate pack becomes, and how much floor space and headroom the installation requires. Reaching a fixed area with 2000 mm plates means fewer, larger chambers; reaching the same area with 870 mm plates means more chambers and more individual plate movements per discharge cycle.

For a buyer, this translates into a straightforward rule: fix filter area first from the duty calculation, then select the plate size that fits the building, the cake handling equipment and the maintenance resources on site. The XMAG envelope from 30 m² at 870 mm to 1000 m² at 2000 mm exists precisely because those two decisions have to be made separately.

Filtering Pressure: Feed Pressure, Squeezing Pressure, and the Number in the Quotation

Membrane press performance is governed by two pressures acting in sequence. During filling, feed pressure drives slurry through the feed channel into each chamber. In the XMAG series this is specified at 0.6–2.0 MPa. After the cake forms, the membrane is inflated at the squeezing pressure — 1.6 MPa in the XMAG specification — which compresses the cake from the inside of each chamber and displaces additional liquid. This secondary squeezing is the mechanism behind the yield advantage of a membrane press: Dazhang's technical documentation states that it can reduce cake moisture by approximately 5–15% compared with conventional chamber filter presses, while also shortening filtration cycles.

Dazhang's wider machine range extends beyond the XMAG envelope. Automatic membrane and chamber filter presses are documented with filtration pressure from 0.6 MPa to 4.0 MPa, and high-pressure round plate presses are documented with feed pressure up to 2.5 MPa for kaolin, ceramics and mineral slurry duties where square chamber designs are insufficient. A buyer comparing quotations must therefore verify which figure applies to the machine offered: a feed pressure, a squeezing pressure, or the maximum structural rating of the frame and plate assembly. Pressure ratings apply to the complete assembly, not to the membrane plate alone.

Membrane Plate Material and Frame Construction

The XMAG series specification lists PP/TPE membrane plates and a Q345 steel frame, while other automatic presses in the same portfolio — such as the 1100/1500 mobile cloth membrane units — are documented with PP filter plates and a carbon steel frame. The material choice is a durability decision, not a preference.

Polypropylene remains the baseline plate material in industrial filtration, and Dazhang manufactures its own plates, including a processing-free sealed square polypropylene filter plate that received invention patent protection and entered the European market, as well as high-temperature-resistant and toughened PP polymer grades. Published technical comparisons from the company indicate that this membrane press platform can operate at temperatures up to 120 °C, whereas conventional PP filter presses typically operate at a maximum of 80 °C — a difference that decides whether a hot slurry can be processed directly or must be cooled first.

Frame grade follows the same logic. The frame carries the clamping load of the entire plate stack, and that load grows with plate size and chamber count. Buyers should require the frame material and the maximum clamping rating to be stated explicitly in the offer, particularly when the selected model sits at the upper end of the 870–2000 mm plate range. A heavier frame is more robust but also adds transport and foundation cost.

Automation Scope and Drainage Type

"Automatic" is a commercial description, not an engineering specification, and its content varies between suppliers. On this platform, automation typically covers hydraulic closing and pressure holding, the membrane squeezing sequence, cake discharge and, in the cloth-traveling variants, automatic cloth washing. The company documents that hydraulic closing with automatic pressure holding cuts manual tightening work by 80% compared with manual stainless steel plate and frame filter presses. Automatic cloth washing is described as reducing cloth clogging and manual maintenance, which supports stable filtration efficiency over long production periods.

Drainage configuration is a further decision that buyers often defer too long. Automatic membrane presses in this range are documented with a visible or invisible drainage option. Visible drainage leaves the filtrate outlets observable, so operators can see flow from each outlet and identify cloth failure, sealing problems or uneven chamber filling at an early stage. Invisible, or closed, drainage routes filtrate through internal channels, which reduces open liquid surfaces and limits vapour or odour exposure — generally preferred for volatile, odorous or hygiene-controlled media. The trade-off is that closed drainage removes the visual diagnostic signal, so instrumentation and monitoring become more important.

Where XMAG-Class Presses Fit: Application Patterns

Automatic membrane filter presses are most often selected for duties that require deep dewatering rather than simple solid–liquid separation. Documented application patterns for this class of equipment include sludge dewatering in municipal and industrial wastewater treatment, mining and coal slurry processing, flue gas desulphurisation gypsum dewatering, chemical processing, food processing, metallurgy and new energy materials.

Capacity ranges help to position a project quickly. Automatic membrane presses with automatic cloth washing are documented across 100–1000 m² of filtration area for wastewater, mining, chemical and new energy duties, while the cloth-traveling and washing variants are documented across 20–291.2 m² for mining, coal slurry, FGD gypsum and sludge. For smaller or parallel-process duties, once-open automatic presses are documented at 4–55 m², and lab-scale presses at 0.32 m² for test work. A buyer who knows the required duty and the site constraints can usually eliminate most of a catalogue in one pass through these ranges.

Market Context: What Is Driving Configuration Decisions

The equipment decisions above sit inside a market that is expanding and concentrating at the same time. According to Grand View Research, the global membrane filtration market was valued at USD 19.4 billion in 2025, with Asia Pacific holding a 36.5% revenue share in the same year. Chinese filter press machine exports under HS code 84212910 reached USD 170,236,194 in 2023, according to China Customs data as reported in secondary trade analysis — an indication of how much dewatering equipment demand is now met from Chinese manufacturing clusters. A separate commercial research estimate places filter presses at approximately 22% of the global sludge dewatering system market in 2024.

For buyers, the practical consequence is not that more suppliers exist, but that specification discipline becomes the only reliable differentiator. When many suppliers offer presses in the same nominal range, the deciding factors shift to verifiable plate size, stated pressure ratings, documented plate material grades and a written automation scope.

Where a Membrane Press Is the Wrong Choice

A membrane filter press is not a universal upgrade, and the limitations are as relevant as the advantages. Three boundaries matter most.

First, investment and maintenance. Membrane presses carry a higher initial cost than standard chamber designs, and the automated components — membranes, hydraulic systems, cloth washing — add maintenance complexity. Dazhang's own comparison data state plainly that the initial investment is higher than that of standard membrane filter presses and that maintenance is more complex because of the automation. Second, standard dewatering duties may not justify the extra cost: chamber filter presses are documented with lower investment and lower operating cost, a simple structure, and filtration pressure covering 0.6–4.0 MPa, which is sufficient for many standard sludge, mining, chemical and ceramics duties. Third, low-pressure fine filtration is a different machine class altogether: plate and frame presses are documented with filtration pressure up to 0.5 MPa and typically manual cake discharge, and are optimised for filtration accuracy rather than high-pressure dewatering.

Filter press frame, plate and assembly production at the Dazhang Filtration manufacturing base, Yuzhou, Henan Province.

Procurement Checklist Before Ordering

The checklist below converts the discussion above into confirmation items. Each line should be answered in writing in the supplier's offer, not inferred from a general brochure.

Future Outlook

Two directions are visible across this equipment class. The first is automation depth: cloth traveling and washing systems, once limited to specific heavy-duty duties, are increasingly specified as standard on larger automatic membrane presses because they hold filtration efficiency stable and reduce manual maintenance. The second is polymer plate development. Manufacturers such as Dazhang continue to work on polypropylene plate materials, membrane plate structures, high-temperature-resistant and toughened grades, and intelligent control systems — a research direction that matters to buyers because plate and membrane performance, not frame fabrication, increasingly sets the practical limits of cake dryness and cycle time.

For procurement teams planning a press purchase over the next few years, the implication is to specify the plate and membrane system explicitly, and to treat automation as a list of functions rather than a single adjective. Equipment that is specified this way remains comparable across suppliers and across future tenders.

Procurement FAQ: XMAG Model Selection and Configuration

Reference Material

For readers who need the manufacturer's own documentation on filtration equipment scope, capacity ranges and service capabilities, the English company profile of Henan Dazhang Filtration Equipment Co., Ltd. is available for download: Da Zhang Filtration Company Profile (PDF).