WASTE MANAGEMENT
PIH-91
pork industry handbook
COOPERATIVE EXTENSION SERVICE • PURDUE UNIVERSITY • WEST LAFAYETTE, INDIANA
Pumping Liquid Manure from Swine Lagoons and Holding Ponds
Authors
Conrad B. Gilbertson, USDA-ARS, Lincoln, Nebraska
Paul E. Fischbach, University of Nebraska
Ronald E. Hermanson, Washington State University
Stewart W. Melvin, Iowa State University
John M. Sweeten, Texas A&M University
Reviewers
Fred Bergsrud, University of Minnesota
L. W. Jacobs, Michigan State University
A. E. Peterson. University of Wisconsin
Hugh O. Vaigneur, University of Tennessee
Manure management is an integral part of a modern swine production system. If manure is not handled in a sanitary method, diseases or other problems can occur, reducing overall production efficiency. Facilities with slurry or liquid storage require careful equipment design to adequately distribute the material to a terminal site. The terminal site is usually cropland.
Design Factors
Design factors which must be considered when planning a swine manure distribution system are:
•	climate,
•	soil type,
•	crops and their nutrient requirements (based on soil fertility test and type of crop),
•	volume of manure to be applied (wet volume and dry weight basis),
•	quantity of manure to be applied (based on nutrient content),
•	possible salt and nutrient imbalances,
•	environmental and legal considerations of the application site.

Once these basic design factors have been considered and preliminary calculations have been completed, the system can be planned. System design consists of four steps:
•	selecting the pumping plant,
•	selecting a distribution system (sprinkler or surface application equipment),
•	sizing the pumping plant and distribution system, and
•	establishing a management system to optimize equipment, energy use, labor and nutrient recovery.
Pumping Plant Selection
Pumping consists of lifting and pushing a liquid through a transport pipe to the application site (Fig. 1). To select the proper pump, consider pump capacity (gal./min.), suction lift elevation, the elevation difference between the pump and the application site, friction loss in the transport lines, pump efficiency, required pressure, and the maximum horsepower that may be used on the power source.

Pumping capacity must be determined on a site-specific basis. Determine the maximum amount of manure to be applied by estimating manure production and volume of flush or wash water used. Another pump capacity selection factor is the method of distribution, either a big gun, a low-pressure gated-pipe distribution line, or a conventional sprinkler irrigation system.

Calculate the total dynamic head the pump must work against. The total dynamic head is calculated by adding the suction lift elevation to the discharge elevation from the pump to the highest point in the system, plus friction loss in the transport pipe, plus the pressure needed at the nozzle. Lift head and elevation head are site specific. Determine the friction loss and required nozzle pressure from friction loss tables and the sprinkler manufacturer, respectively.

All pumps have a maximum theoretical suction lift height of about 34 ft. However, a practical limit is 20 ft. or less due to pump limitations (small pump and suction line leaks, friction loss, etc.). Many common pump problems occur with the suction side of the pump. Pumps with small leaks in the suction lift pipe or those in poor repair will not develop enough lift for satisfactory performance. Minimize the suction lift or use flooded suction where possible.

Pump speed has a direct effect on capacity, pressure head developed, cavitation, and frequency of repair. Many smaller pumps are designed to run at 3,450 rpm with direct