Myth: Plate and frame describes all types of plate Filter Presses
“板框压滤机”一词经常被用来描述现代板框压滤机脱水技术.
Flat surface plate and frame
The plate and frame Filter Press was one of the earliest types of plate Filter Press designs.
这个设计有一系列的空心框架和平面板堆叠在一起，并在轨道上支撑. 在每个框架和板之间放置编织布材料，以收集浆料固体，并允许液体通过. 通过机械螺丝或液压滑块将交替的框架和板堆叠在一起.
With the stack being held tightly together, 浆料通过某种类型的泵送作用被强制进入框架腔. 只要滤液通过布流出，浆液中的固体物质就会继续在框架中积聚. 当没有额外的浆料可以强制进入框架时，泵送动作停止. 框架和盘子被松开，然后分开一个时间，让脱水的蛋糕材料掉出框架.
板框设计的一个固有问题是，当打开时，脱水的饼料不会掉出框. Several types of frame shake mechanisms are used to promote cake discharge, but often the operator has to manually dislodge the material from the frames.
Recessed plate
Most modern-day plate Filter Presses employ a “recessed” plate design to replace the frame and flat plates.
When adjacent recessed plates are held together, a chamber space is formed. Filter cloths cover both sides of the recessed plates. Just like a plate and frame press, the slurry is pumped between the clamped stack of recessed plates, where the dewatering occurs. 一旦饼形成，进料泵停止，板堆松开夹紧. When the recessed plates are separated, 蛋糕更容易从盘子里出来，而不会被架子挡住.
用来描述这些脱水技术的一个更通用的术语是板式压滤机. 这两种凹进式板和板和框架设计的压滤机在许多脱水应用中使用的今天. A third common design, membrane plate Filter Presses, 采用具有柔性板面，可扩展到饼空间压缩成型饼的凹式板, resulting in additional liquid removal. 膜板只有在被脱水的材料是可压缩的情况下才有效.
Myth: The hydraulic cylinder actually squeezes the liquid out of the cakes
与板式压滤机有关的一个常见误解是，被脱水的物料是通过液压动力单元/气缸在滤板之间挤压的. In reality, 大多数现代板式压滤机设计中使用的液压缸仅用于将滤板压紧在一起，并防止浆液进料压力迫使板分离.
Hydraulic power unit.
Once the plate stack is held tightly together, the slurry is fed into the chamber spaces between the plates. 泵送作用和由此产生的浆液进料压力是产生脱水作用的原因. 泵送动作继续进行，直到很少有额外的浆液被强制进入压滤机. When the pumping action is stopped, 液压缸用于充分打开板堆，使每个板可以单独分离, allowing the cakes to discharge by gravity.
Hydraulic cylinder.
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Myth: Chemicals are always required in dewatering slurry materials
当使用板式滤速技术时，通常不需要化学添加剂来帮助脱水.
现代板式压滤机可在100 psi (7 Bar)至225 psi (15 Bar)的高泥浆进料压力下运行。, or more in special applications. 这些高泵送压力在板式压滤机中是可能的，因为滤板通过非常高的机械或液压压力紧密地结合在一起, typically 2500 psi (175 Bar) to 5000 psi (345 Bar). Because the slurry material is exposed to high feed pressures, 无需化学助剂或添加剂，可实现更高的脱水效率.
Other common dewatering technologies, such as belt Filter Presses or centrifuges, 不能产生很高的浆料脱水压力，通常需要化学添加剂来达到合理的脱水效率.
Myth: Dewatered filter cakes are dry solid cakes
使用板式压滤机可以从浆液中去除的液体量很大程度上取决于被脱水材料的类型和质量.
Dewatered cakes collect in a bunker beneath the Filter Press.
As the liquid is removed from a slurry, 粒子变得更紧密地聚集在一起，最终形成一个“固体”质量，不再容易流动. Depending the specific material characteristics, 固体质量可以在高达50%的液体仍与固体一起形成.
Filter Presses dewater slurry from a liquid to a more manageable form.
In nearly all cases, 即使物料非常有效地脱水，脱水后的滤饼中仍会残留少量(10%至25%)的液体.
Dewatered filter cakes.
影响浆料脱水特性的一些主要因素包括浆料浓度, particle size distribution, shape and origin. 较粗且形状不规则的物料浆体更容易脱水, while fine particle slurries can be very challenging to dewater. 扁平或均匀形状的细颗粒浆料更容易堆积在一起, as liquid is removed and can become very difficult to dewater. One of the most difficult slurries to dewater is a very fine particle size, flat shaped clay material.
Myth: All slurry materials have similar dewatering characteristics
浆料是由干燥的固体颗粒与液体(通常是水)混合而成.
Solid particles are described by their chemical makeup, particle size distribution, particle shape, specific gravity, abrasiveness, sharpness, hardness and purity. When mixed into a slurry, additional characteristics such as slurry percent solids, specific gravity, viscosity, particle charge and pH are used to describe the solid/liquid mixture. 许多, if not all, 这些固体材料和浆料的特性会影响浆料脱水的难易程度. Because of the many characteristics involved, 这就更容易理解为什么没有两种浆体材料具有相同的脱水特性.
了解特定浆料脱水特性的最佳方法是通过某种类型的 laboratory or on-site pilot material testing. 为了获得最准确的结果，必须取有代表性的浆料样品进行测试. Sample testing results will typically include slurry percent solids, particle size distribution, slurry pH, slurry specific gravity, filtration rate, final dewatered percent solids, and filtrate water ppm (parts per million) solids. 准确的全尺寸设备尺寸和容量可以准确预测一次固体物料, slurry and dewatering testing is completed.
