Volatiles, moisture and

It is important to note that coal rank has little to do with quality. As a coal matures its ash content actually increases as a proportion because of the loss of moisture and volatiles. Lower rank coals may have lower energy contents, but they... 

Contaminated soil is fed into a rotary dryer where the temperature is raised to between 500 and 800°F. As the soil is heated, moisture and volatile organic compounds (VOCs) are vaporized. The heated exhaust gases from the dryer are forced through a baghouse where soil fines and dust particles are removed. Exhaust gases are then passed through a catalytic oxidizer to remove hydrocarbons. 

Determination of Moisture by Alternate Method. This includes moisture and volatiles. For rapid determination use the "oven method" described in MIL-STD-650 as Method 101.5 ... 

Moisture by Karl Fischer Titration (1290—93) Moisture and Volatiles by Oven Drying at 100° (1294)... 

This method is used for determining the moisture and volatile solvent content of sheet propellant (such as M-8 propellant) and other propellants where the chief constituent evolved is moisture. The method is generally not applicable to propellants not in sheet form. 

Two tests are current in the USA for the determination of moisture and volatiles in expls. They are contained in Military Standard-Explosive Sampling, Inspection and Testing , MIL-STD-650 (3 Aug 1962), and are reproduced below verbatim ... 

Determine the loss in weight, and calculate (by weight) the percentage of moisture and volatiles in the sample. 

This method is used for determining the moisture and volatiles, on the basis of loss of weight on heating at 55° 2°C. under vacuum, on multi-component explosives that contain material that would be damaged by 100°C. heat treatment at atmospheric pressure. 

Follow the procedure described in Method 101.5 for the determination of the percentage moisture and volatile in the explosive. However, in this determination heat for 6 hours in a vacuum oven at a temperature of 55° 2°C. and a pressure (absolute) of 80mm 10mm of mercury instead of four (4) hours in an oven at 100° 5°C. and atmospheric pressure. 

The crystalline PETN is separated from the solvent in a vacuum filter down to a 15-20% acetone content. The residual acetone is later removed by washing with a small amount of ethyl alcohol. The final product is dried at 40°C. PETN crystallized from acetone should fulfil the following conditions m.p. 138-140°C, content of moisture and volatile components max. 0.1%, substances unsoluble in... 

During drying opn, samples of proplnt are sent to the lab to det if the required external moisture and volatile solvent contents have been reached. The desired external moist content for air-dried proplnts varies inversely as the size of the grain from ca 0.1 to 1.0%, while the total volatile content of the dried proplnt may vary from ca 3.5 to 7.5%, depending upon the web thickness - the heavier web proplnts having the greater solvent contents... 

A shaking device, near the bottom, is regulated in such a manner that the rate of discharge and consequently the volatile content of the proplnt, is controlled by the speed atwhichthis shaker is operated and by the amt of clearance betw the shaker and the bottom of the shute. The time required for drying is betw 4 and 5 hrs. One of the installations operating in the US before WWII was capable of drying to correct moisture and volatile contents 100000 lbs of 75 mm pro-pint in 24 hrs... 

Some coal analyzers use several gamma-ray detectors and operate by the use of neutron pulses. Such analyzers can measure the density and sulfur content of coal along with its heating value, moisture, and volatile matter content. This pulsed fast/thermal neutron analyzer can be self-calibrating and can determine such elements as carbon, oxygen, and sodium. 

Pelletizing (cf. tumbling agglomeration ) Green balls or pellets of ore or minerals are hardened by heat treatment with attendant loss of moisture and volatile matter. Pellet induration, pellet firing Travelling grate, rotary kiln, vertical shaft furnace... 

Petroleum coke calcining is a process whereby green or raw petroleum coke is thermally upgraded to remove associated moisture and volatile combustible matter (VCM) and to otherwise improve critical physical properties, e.g., electrical conductivity and real density (JL ) The calcining process is essentially a time-temperature function the most important variables to control are heating rate, VCM to air ratio and final temperature. To attain the calcined coke properties necessary for its end use by the amorphous carbon or graphite industries, the coke must be heat treated to temperatures of 1200-1350°C (2200-2500°F), or higher, to refine its crystalline structure. 

Moisture and Volatile Matter (M V)— AOCS Method Ca 2d-25(97) and insoluble impurities—AOCS Method Ca 3a-46(97) (<0.3%)... 

Moisture and Volatile Matter—Air Oven Method (M V) (Ca 2c-25) determines the moisture and volatile matter by heating in a hot air oven. This method is applicable to animal and vegetable fats, but not to drying oils, coconut group fats, or oils with added monoacylgly cerols. 

Some coals contain an ash in addition to carbon, moisture, and volatiles. To obtain a conservative estimate, one should assume that a porous ash shell is retained during the burning of the combustible material. This ash may, of course, have a catalytic effect on the heterogeneous carbon combustion reactions however, it is a cause for additional diffusion resistance. 

However, in many cases the pyrolysis products are amorphous. For instance, the polysilazane-derived silicon carbonitride mentioned above crystallizes only when it is heated above 1450 C, and its characterization is difficult. Elemental analysis poses problems, in part because the pyrolysis product is very porous. As a result of its high surface area, the material adsorbs moisture and volatiles very readily, and improper prior handling and preparation for analysis can result in misleading results. 

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