The pulp concentration refers to the content of solid materials in the pulp. There are usually two ways to represent it:

Where C is the weight percent concentration of the pulp, %;
R——the liquid-solid ratio of the slurry;
P ₁ - the weight of the solid in the pulp, gram;
P ₂ - the weight of water in the pulp, gram;
P - pulp weight, gram.
The relationship between the concentration of the slurry and the liquid-solid ratio is 1/C = 1 + R.
There are various methods for measuring the concentration of the slurry, such as direct measurement, indirect measurement, and automatic measurement. The manual measurement method is described here.
1) Direct measurement method Take the slurry sample with the sampling tool, weigh the weight P of the slurry, then filter and dry the slurry to constant weight. After cooling, weigh the solid dry weight P ₁ and calculate the slurry concentration according to formula 2-23. . This method is accurate, but the processing process is long, which is inconvenient for promptly guiding the on-site operation. This method is commonly used in process testing.
2) Indirect measurement method The concentration of the slurry is converted by measuring the specific gravity of the slurry. The specific method is to use the slurry concentration pot to determine. Generally, the volume of the pot is set to 1000 liters, the weight of the pot is W1, the weight of the pot after filling the water is W ₂ , and the weight of the pot after filling the pulp is W ₃ , then the specific gravity of the slurry is: