| Water testing | 5 | ° | Baume | 166 | lbs. dry copperas |
| Water testing | 4 | ¹⁄₂° | Baume | 150 | lbs. dry copperas |
| Water testing | 4 | ° | Baume | 133 | lbs. dry copperas |
| Water testing | 3 | ¹⁄₂° | Baume | 117 | lbs. dry copperas |
| Water testing | 3 | ° | Baume | 100 | lbs. dry copperas |
These varying amounts of copperas are put into a barrel of hot water and thoroughly stirred until dissolved. The solution is then poured into a vat of tank water, the mass allowed to stand six or eight hours, and then skimmed off before being pumped to the evaporating machine.
Solids in Water.
—The percentage of solids and liquids, as well as the respective weights in tank water at different degrees Beaume, are shown in the following table:
TABLE FOR TANK WATER.
| Degrees Baume | Per cent solids | Per cent water | Weight of cubic foot | Weight of gallon |
|---|---|---|---|---|
| 1 | 1.90 | 98.10 | 62.14 | 8.30 |
| 2 | 3.83 | 96.17 | 62.46 | 8.34 |
| 3 | 5.77 | 94.23 | 62.79 | 8.39 |
| 4 | 7.77 | 92.23 | 63.11 | 8.43 |
| 5 | 9.85 | 90.15 | 63.43 | 8.47 |
| 6 | 11.93 | 88.07 | 63.91 | 8.54 |
| 7 | 14.04 | 85.96 | 64.41 | 8.60 |
| 8 | 16.19 | 83.81 | 64.89 | 8.67 |
| 9 | 18.38 | 81.62 | 65.38 | 8.73 |
| 10 | 20.60 | 79.40 | 65.81 | 8.80 |
| 11 | 22.71 | 77.29 | 66.39 | 8.87 |
| 12 | 24.84 | 75.16 | 66.92 | 8.94 |
| 13 | 26.97 | 73.03 | 67.44 | 9.01 |
| 14 | 29.11 | 70.89 | 67.97 | 9.08 |
| 15 | 31.27 | 68.73 | 68.49 | 9.15 |
| 16 | 33.55 | 66.45 | 69.05 | 9.23 |
| 17 | 35.88 | 64.12 | 69.61 | 9.30 |
| 18 | 38.22 | 61.78 | 70.17 | 9.37 |
| 19 | 40.59 | 59.41 | 70.72 | 9.45 |
| 20 | 42.98 | 57.02 | 71.28 | 9.52 |
| 21 | 45.11 | 54.89 | 71.89 | 9.60 |
| 22 | 47.24 | 52.76 | 72.79 | 9.68 |
| 23 | 49.37 | 50.63 | 73.09 | 9.77 |
| 24 | 51.50 | 48.50 | 73.70 | 9.85 |
| 25 | 53.63 | 46.37 | 74.30 | 9.93 |
| 26 | 56.31 | 43.69 | 74.95 | 10.01 |
| 27 | 59.04 | 40.96 | 75.60 | 10.10 |
| 28 | 61.80 | 38.20 | 76.25 | 10.19 |
| 29 | 64.61 | 35.39 | 76.90 | 10.27 |
| 30 | 67.54 | 32.46 | 77.55 | 10.36 |
| 31 | 70.34 | 29.66 | 78.35 | 10.46 |
| 32 | 73.27 | 26.73 | 78.94 | 10.55 |
| 33 | 76.24 | 23.76 | 79.64 | 10.64 |
| 34 | 79.25 | 20.75 | 80.33 | 10.73 |
| 35 | 83.21 | 17.79 | 81.00 | 10.83 |
Drying 29° Beaume Stick.
—This is done in two ways, by the use of drying rolls and by mixing with drying tankage in a rotary dryer. When drying stick over the rolls, evaporate it in the evaporators to 26° Beaume and mix with this 26° Beaume stick, about 17 per cent of copperas before putting the mixture over the rolls. This has a tendency to prevent the concentrated tankage from absorbing moisture when in storage. Many operators dry stick without the use of copperas, but the copperas prevents in a measure the stick absorbing moisture from the air.
Stick Rolls.
—[Fig. 74] shows a standard twin stick roll. This equipment is made of two cast iron rolls built when new to sustain 50 lbs. pressure. The stick is deposited in a pan beneath and the revolving roll collects a film of substance which is dried as the roll revolves and is sliced from the surface of the roll by a close fitting scraper, being removed in a powdered form.