Roll Presses

压力机的大小是由什么类型的材料被喂进它和它是如何被喂. Most of the current installations involve manure dewatering. Here is a chart showing the different sizes and capacities. For applications other than manure, please contact McLanahan’s agriculture team for sizing and selection.

This depends on the goals of the system. 如果目标仅仅是将材料脱水到可以用装载机搬运到地里, a single-stage press is usually sufficient. 如果有其他脱水目的，那么双压机或单压机可能是一个好主意. This chart shows the amount of dewatering that happens at each press stage.

A small tank compressor is all that’s needed. 一旦空气弹簧充满了空气，它们在运行过程中消耗的空气很少.

A UHMW scraper is standard. In the case of long, stringy materials like fruit stems or even shredded plastic, which can build up under a scraper, a motorized brush is used. 

辊压机和螺旋压机都是在高压下从固体物料中挤出水分的原理下工作的, but each does so in a slightly different way.

轧辊压力机包含两个轧辊，它们相互反向旋转，并在一个称为夹点的小区域相互接触. This is the point where pressure is applied between the two rolls. 底部辊子有排水孔，一旦水被挤出，就可以让水逸出. The top roll is solid, 通常用比普通钢稍软的材料建造或覆盖. Many times this material is rubber or urethane. 加厚的材料被送入辊的顶部，靠近夹点. 当滚筒旋转时，它们把材料拉过去，高压把水挤出来. 辊压机的高压点不存在滑动磨损, so they are great to use when sand is used as a bedding material. 除非进料浆的总固体(TS)浓度很高，否则辊压机不适合作为初级分离器. With dairy manure, this would need to be about 12% TS or higher. 

A Screw Press can handle much lower total solids concentrations and higher incoming flow rates; therefore, 既可作一次分离器，也可作二次脱水机. Unlike a Roll Press, which uses two counter rotating rolls to create a nip point, a Screw Press uses a rotating auger contained within a screen. 螺旋钻不断旋转，同时物料涌入筛网内部. 较大的纤维被困在屏幕上，而液体和较小的颗粒通过. As the auger rotates, 它将捕获的纤维从筛网上刮下来，并将其推进到排放口. 当纤维接近放电时，它们开始形成一个厚的材料塞. 机器前部的桨阻碍了它们的前进运动，塞子被迫减速，压力开始形成. It’s in this high pressure plug where dewatering occurs. 为了确保捕获的纤维向前推进到脱水区，螺丝和筛网之间的紧密公差是必要的. 由于这些紧公差和发生在螺杆和筛网之间的滑动磨损, 如果存在砂层，螺旋压榨机不是脱水粪便的最佳选择.