In many cases, the manufacturer will have a local representative who can assist in developing application procedures. The local representative may also have an applicator or can recommend a local applicator; however, the operator of the hazardous waste site can apply the dust suppressant if the proper equipment is available.
Dust Control Handbook File
The nature of the business is such that product manufacturers come and go quickly. Therefore, some products may no longer be available, whereas some new products may not be listed. Listing of these products does not constitute an endorsement. Roadway Preparation- Regardless of whether water or chemicals are used, proper roadway prepa- ration is essential for dust control.
Preparation steps include adding aggregate to the surface as required to obtain the size gradation in Table , and grading the road with a center crown and ric low spots for water to collect. Grading will probably be required every weeks with watering. With chemical suppressants, grading after application of the dust suppressant will almost totally destroy control effectiveness; therefore, an excellent final grade should be put on the road before the final chemical spray. The road should not be regraded until :'ust before the second chemical application weeks after the initial application.
Spray Equipment-- Chemical dust suppressants and water are most commonly applied with water wagons equipped with two to five nozzles that shoot a flat spray behind the vehicle. The flow-control system is often crude and difficult to regulate, and it is not usually tied to vehicle speed. Therefore, it is difficult to regulate the quantity of material sprayed. Nonetheless, it is by far the most common method used.
A calibrated spray bar is more suitable for the application of chemical dust suppressants. The most sophisticated systems allow the operator to specify an application rate and the truck will automatically regulate the speed and spray rate.
Some but not all bitumens must be applied with an asphalt distributor because the material must be heated before application. Costs-- Certain costs are incurred in all dust suppressant, programs. These include labor and material costs associated with road surface preparation, cost of the dust suppressant used, application costs, and road maintenance costs grading, watering, and supplementing aggregate.
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Lindbergh Blvd. Mining Chemicals Park Ave. New York, NY None 0. Box Park Falls, WI Box Canton, OH 0. Box Bellingham, WA X 0.saltingdimis.ml
Dust Control Handbook
X East Ogden Ave. X 2. Sulfur Products Market St. Sciences Market Street - -P. Woodruff Ave. Toledo, OH 0.
Dust Control | Santa Barbara County Air Pollution Control District
Products listed are not endorsed over products not listed. Water: product. Assumptions used for the analysis are shown in Table The bases for these assumptions are as follows: 0 Product costs which were obtained from each vendor, represent the least expensive per gallon cost available. Shipping costs represent the least expensive method of shipping to an eastern mine southern Illinois and a western mine southern Wyoming. This removes geographic advantages.
Rates vary by mine depending on local contracts and machinery type and age. This is an inaccurate assumption, but no reliable cost data could be found. Identical parameters were used for all chemicals mixed in place, and a second set of activity parameters was used for all topical applications. These assumptions were used to calculate costs associated with the use of chemicals and water for dust suppression. The analysis of chemical dust suppressants was limited to mixed and topical applications of calcium chloride and mixed-in-place applications of lignon.
Table presents a comparison of the cost-effectiveness of four controls for achieving a minimum 50 percent control level. The limited results show that topically applied salt or mixed-in-place adhesive are more cost-effective than watering. The selection of dust suppressant strategies, however, should also be based on other considerations related to road construction and spil- lages as explained later in Section 2. Reapplications of the chemicals would probably result in higher control efficiencies than the initial application because residual traces of the control material still remain.
Therefore, this analysis, which is based on initial applications, may overestimate the cost of a long-term chemical pro- gram. Watering has no such cumulative control effects. Also, the analysis was performed for a mine haul road, where heavy vehicles and high speeds make dust suppression more difficult than it would be at a typical hazardous waste site.
The less frequent application at these sites might lower the estimated costs. Water Activity Mixed Topical Application frequency 16 8 0 Depends on effective- ness of individual product 8 2 0. Cost assumes foot and foot-wide road in East and West. Compara- tive costs could not be calculated. It can exceed the cost of the material. The smallest delivery quantity of most suppressants is e.
The material must be pumped or poured in the applicator. A more economical way to buy the material is in a tanker truck. If no onsite storage tank is available, the tank trailer can be left on site and the material pumped as required. The material is also available by train tanker car. Again, on-site storage facilities are required, or the tanker car must be stored on a siding. For example, a change in speed from 30 to?. Although this factor may overestimate emission reductions resulting from reduced speed, the principle holds. The cost of imposing speed control is increased labor and equipment time to haul material.
Housekeeping Practices- Housekeeping refers to cleaning up spills and track-on material left by the trucks. These materials will not. Costs include labor and equipment time to remove. The best way to minimize housekeeping is to minimize spills and carryout. Measures to minimize spills include the use of trucks with tailgates as opposed to scows, eliminating truck leaks, not overfilling trucks, and covering loads.
The best way to minimize carryout is to eliminate muddy areas by regrading or gravelling them, and by installing a truck tire and underbody wash over a grate and requiring all trucks to pass through it. This control is far more efficient than water, chemicals, speed control or housekeeping. Maintaining this control efficiency, however, requires continued cleaning of the paved road.
The control methods used on these roads are manual cleaning, mechanical sweeping, vacuum sweeping, flushing, and general housekeeping practices. The objective of these efforts is to remove all loose dirt, particularly fine particles. Manual Cleaning-- Manual cleaning may be adequate for short sections of road, but it is a very labor-intensive approach. Mechanical Sweeping-- Mechanical street sweeping is the most common means of control; however, it is relatively ineffective in the removal of fine particles. In one series of tests, material consisting of particles 74 to micrometers in size was applied to a paved street at a loading of grains per square foot.
Removal efficiency was 46 to 63 percent. Silt-size particles, less than 74 micro- meters are the particles most likely to be entrained. Removal efficiency of mechanical sweeping for this size particle is probably less than 46 percent.
In addition, the act of street cleaning itself creates dust because of the impact of the cleaning vehicle tires on the road, the brushing of dry pavement, and wind turbulence caused by exhaust and vehicle movement. Unless the street is very dirty, the net improvement in ambient air quality as a result of sweeping will be small or negative. Vacuum Sweeping-- Vacuum sweeping is more efficient than mechanical sweeping. In the same experiment just discussed, collection efficiencies of 90 to 92 percent were observed. Again, collection efficiency would probably be less for silt-size particles, and again, some dust emissions are caused by the sweeper itself.
Often flushing is used in conjunction with vacuum sweeping rather than "as the sole method of cleaning.