Particulates grain dust

Grain dust (oat, wheat, barley) — 4 (total dust/ particulate)... 

Three of the disadvantages of ESPs are as follows (1) the initial cost is the highest of any particulate collection system, (2) a large amount of space is required for the installation, and (3) ESPs are not suitable for combustible particles such as grain or wood dust. 

Air Filters The types of equipment previously described are intended primarily for the collection of process dusts, whereas air filters comprise a variety of filtration devices designed for the collection of particulate matter at low concentrations, usually atmospheric dust. The difference in the two categories of equipment is not in the principles of operation but in the adaptations required to deal with the different quantities of dust. Process-dust concentrations may run as high as several hundred grams per cubic meter (or grains per cubic foot) but usually do not exceed 45 g/m3 (20 gr/ft3). Atmospheric-dust concentrations that may be expected in various types of locations are shown in Table 17-8 and are generally below 12 mg/m3 (5 gr/1000 ft3). 

The origin of Aeolian dust from Chinese desert to Japanese islands was studied with ESR of dust, mostly fine grains of quartz.132 Suspended particulate matter (SPM) collected by environmental protection agency was measured with ESR.133 Dust soot of automobiles was also measured to check the motor combustion rate. Adsorption of NO, Mn2+ and Gd3 on clay minerals, bentonite and se-piolite134 has been studied using paramagnetic ions as tracers for radioactive elements. And studies have been carried out on how divalent and trivalent cations diffuse and blocked by surrounding clay minerals, in the context of their leak from nuclear waste repository to the environment.135... 

While particulates are primarily sampled to determine toxic effects upon workers, explosivity may also be of concern. Dusts such as grain may explode when concentrations are sufficiently elevated and an ignition source is present. When monitoring is done to evaluate explosive hazards in the occupational environment, dust-to-air concentrations, as well as particle size and sources of ignition, must be determined. 

The PM control devices typically used in the grain dryers are screens, cyclones, and fabric filters. In the food and feed industries, cyclones, baghouses, and wet scrubbers are used to control solid particulate emissions. However, as with any organic dust, food processing dusts also have a high explosion tendency. Hence, special care is required to select, size, and operate the control devices. Emission factors for various dryer types utilized in alfalfa dehydration plants... 

---