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Chapter 4.1

planning. In addition, existing manure storage facilities may be equipped with capacity markers that provide easy estimates of volume present.

The weight or volume of manure in a storage facility can be estimated using direct measurements and calculations. This method can be used in the absence of historical manure application records, and is more operation specific than using standard values. The rest of this chapter will focus on how to measure and calculate volume and weight of stored solid and liquid manure.

Estimating the Weight of Solid Manure

Nutrient content of solid manure is usually expressed as a percentage, or in weight of nutrient per unit weight of manure (e.g., kilograms per tonne). Weight can be estimated by multiplying the volume by the bulk density of the manure. To estimate the weight of solid manure:

Determine the shape of the manure pile. 1. Obtain dimensions of the pile. 2.

Calculate volume. 3. Measure density of material in the pile. 4. Calculate weight. 5.

Determine Shape of a Pile

Identifying the shape of a manure pile is necessary to determine the dimensions and calculations needed to estimate its volume. The volume of any shape is its area multiplied by its depth, although for some shapes these dimensions are not always easy to identify. Solid manure piles are often irregular in shape, but can be visualized as an assembly of several smaller, simple geometric shapes (Figure 4.1.1).

Calculating and adding the individual volumes of these smaller shapes will give the total volume of the pile. This process may require several calculations, but will yield a more accurate volume estimate for irregular piles. To calculate the volume of various shapes, refer to the shapes and associated equations provided in Figure 4.1.2.

Figure 4.1.1 Complex Shapes Broken into Simple Shapes