Agricultural Hydrocyclones

They can be installed as a means of primary separation of sand and grit or installed as a secondary separation process in conjunction with a Sand-Manure Separator or Sand Lane System. In either case, the Hydrocyclone provides high rates of sand and grit removal, leaving a liquid effluent stream that is virtually sand-free.

Hydrocyclones are used for grit and sand removal. They can be used as both the primary and secondary separation steps in manure separation systems, as well as to remove grit in pre-digestion and pre-nutrient separation.

How Agricultural Hydrocylcones Work

Diluted manure enters the feed inlet at a specified flow rate, which is measured as a pressure at the hydrocyclone inlet. As the manure enters the feedbox inlet, it begins to circulate at high speeds within the upper portion of the hollow cone section. As it does this, centrifugal forces act on the sand particles and pull them to the outside of the cone. A mass of sand begins to form in the hollow cylinder while gravity pulls it downward and accelerates it even more. This action further separates the sand and liquid. These heavier sand fractions then exit through the underflow regulator, sometimes called a fishtail or duckbilll, at the bottom of the cone. The remaining liquid and fine particles are pulled upward and exit the Hydrocyclone through the top of the feedbox and eventually the overflow pipe. A siphon bleed valve, attached to a hose on top of the overflow pipe, is used to regulate and adjust the amount of siphon pressure within the overflow pipe. When the valve is closed, maximum siphoning effect is felt within the Hydrocyclone and maximum dewatering occurs with the sand product. With the valve operating in the open position, the sand product will contain a much higher moisture content.

The separated sand product still contains a significant amount of moisture and organic content. Due to the high organic content, it is discharged onto a Sand-Manure Separator, which washes the organic material and produces a clean sand suitable for reuse.

Why McLanahan Agricultural Hydrocyclones

McLanahan Agricultural Hydrocyclones are based on patented technology used for separating, dewatering and desliming aggregates and minerals for more than 40 years. They were first introduced to the agricultural industry in 2002 to provide fine sand removal as a second step in the sand-manure separation process. By adding this secondary step in the separation process, McLanahan sand-manure separation systems have been proven to remove more than 90% of the sand from the incoming manure stream. In flush and flush-flume systems where the manure is highly diluted, a Hydrocyclone can be used as the primary means of separation with the same expected high recovery rates. This high recovery rate allows producers to recycle their sand with minimal annual sand costs. It also provides the dairy with manure effluent containing minimal bypass sand. This is important as the dairy considers long-term manure storage capacities, manure digestion or nutrient separation technologies.

McLanahan Hydrocyclones are available in multiple sizes and flow rates, beginning with a flow rate of about 180 gpm and ending with flow rates in excess of 2,000 gpm. They are designed for high capacities within a small footprint, minimal wear and easy maintenance. All wetted components are lined with a natural rubber compound to reduce abrasive wear from the sand. Once the linings have become worn, components can be replaced or relined. McLanahan engineers work with customers to provide the most efficient pumping and separation system for the their needs.