Flat Bottom Classifiers, like McLanahan Lites-Out™ Classifiers, remove lightweight, deleterious materials, such as lignite and organic matter, from a minus 4 mesh (5mm) sand product stream using hindered settling.
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平底分级机是阻碍沉降分级设备家族的一部分，包括McLanahan加氢浆料机™. 这些装置使用一个致密的流化床，由接近大小的沙子漂浮在轻质物料上，同时允许较重的馏分通过床.
平底分级机主要用于骨料生产商生产建筑用砂，但也可用于特种砂生产, including glass sand and frac sand when organics are present. This technology is also utilized in soils washing for contaminated sites. Typically, contaminants such as PCBs are concentrated in the organics. Lites-Out™非常适合这种应用，在这种应用中，有机物从沙子中分离出来进行处理，沙子可以重复使用.
In a typical Lites-Out™ system, the Flat Bottom Classifier is fed by a Hydrocyclone to provide a controlled, dense and deslimed feed. This slurry enters the top of the unit via a central feed well, 当水通过专门的喷嘴注入一个静压室以产生向上上升的电流时. This establishes a zone of suspended, or teetered, solids. 悬浮液中的固体在分离点(更好地描述为切割点)具有一定大小的分数。, suspended as neither coarser nor finer than the cut desired. 细颗粒/轻颗粒不能穿透这种致密的流化床，它们被上升的水流带过堰，在装置顶部溢出. Coarser/heavier particles are able to penetrate the teetering bed and, by gravity, 通过注水区，通过下泄阀进行收集和排放.
McLanahan lite - out™通过简单的PID控制回路自动保持分离. 操作人员可以设定注水速度和所需的作业密度. The unit requires minimal supervision, Lites-Out™控制系统监控分级环境，并打开/关闭分离室底部的镖阀. The unit automatically compensates for changes in feed rate, and the only moving parts are the underflow valves.
手动截止阀和流量计提供每个单位，所以摇晃水可以很容易地调整. For additional cost, 摇摆水量也可以自动设置和维护使用一个独立的PID回路控制利用气动控制阀.
Lites-Out™装置在哪里用于有机物去除，如土壤洗涤或褐煤去除, the overflow will contain larger organics with the finer sand (equivalent weight particulates); in this case, 级间筛管用于将较大的有机物从较细的砂中分离出来.
Typically, in construction aggregates, 筛孔将与粗底流重新组合并馈送到任何一个 Screws, Hydrocyclones and/or Dewatering Screens to produce a stackable product. 螺丝和水力旋流器有助于进一步去除最细的轻质材料.
The organics are either disposed of with plant effluent, 对污染土壤项目，收集用于场地修复或送高温销毁.
McLanahan经验丰富的工艺工程师可以定制有机物/褐煤去除系统，以满足大多数最终用户的需求. Often these systems are add-ons to existing Classifying Tank systems, required due to changes in the deposits or the market, 或者是用于建筑骨料或污染土壤应用的独立系统. With many systems operating and one-stop-shop, field proven equipment choices, no one can match McLanahan’s offering.
As part of its effort for service and support, McLanahan公司在我们的内部实验室提供沉-浮测试，以评估针对特定应用的Lites-Out™系统的有效性. 比重测试对于选择合适的设备至关重要. Most lignite is in the 1.4 – 1.8 SG range, which is most suitable for removal from the 2.6+ SG sand.
The short answer is no. 值得注意的是，建筑用砂的评估是基于ASTM C-123——集料中轻质颗粒的标准试验方法. In this test ,<50 mesh (-300µm) fractions are not considered part of the test. By the nature of the process, while there is a significant reduction in lignite, the final products are rarely lignite-free. 为了解释这一点，Lites-Out™的溢出物包含轻质材料和精细的可用砂. 这种溢出流被导向筛网，通常是筛网弯曲式的. It will then screen out the coarser lightweight fractions as a waste; however, 含有细砂的筛孔也会含有细轻质材料. This slurry is usually directed to a sump to be pumped to a recovery Hydrocyclone or directed to a dewatering Screw Washer. 水力旋流器和螺旋清洗机都会将大部分轻质物料作为溢流排出，但不会消除轻质物料.
It is possible that this material may be of higher specific gravity. lite - out™的工作液位可以提高到刚好低于溢流堰. 设定点可调高，并可增加摆水流量. 上述所有方法的结合通常会改善这种污染. Slightly reducing the sand screen may also produce the desired effect. If you continue to experience this problem, take samples of the particulates for submission to the McLanahan lab. 在装运样品之前，请从您的经销商或工厂获得必要的文件.
It depends. Flat Bottom Classifiers/ lite - out™基于设置点进行分离，其方式类似于 Hydrosizer™; however, with the batch style discharge, fines can be drawn into the coarse stream from the fluidized bed. Depending on the accuracy required for the individual products, or blend of overflow and underflow, this may not be of concern. 但是，通常情况下，该设备对于压裂砂应用中的离散切割不够精确.
McLanahan lite - out™平底分级机可从砂菠菜网最稳定正规平台_最全菠菜网大全中去除轻质有机物质.
