1 Introduction

1.1 Dust- Definition随堂测验

1、Desert dust containscommon crustal minerals,such as .
    A、silica
    B、calcium
    C、carbonate
    D、iron oxides

2、Dust consists of particles in the atmosphere that come from various sources such as .
    A、soil
    B、dust lifted by weather
    C、volcanic eruptions
    D、pollution

3、On earth,dust forms when rocks are broken down into sand and smaller particles.

1.2 Dust- Classification随堂测验

1、Dust classified by property have .
    A、inorganic dust
    B、organic dust
    C、visible dust
    D、compuound

2、Dust classified by ingredient have .
    A、coal
    B、rock
    C、cement
    D、asbestos

3、Mine dust can not accelerate mechanical wear,short the service life of precision instiuments.

1.3 Dust - Property随堂测验

1、Dust is .
    A、circle
    B、broken and grinded to irregular particles
    C、spherical or cube
    D、aggregation or mixed together

2、Cohesion is dust particles and other objects phenomenon.

3、Adhesion is general combine each other between dust particles to form a new large dust particles.

Chapter 1 Exam

1、What is the size of the visual dust?
    A、<0.25 μm
    B、>0.25 and <10μm
    C、>1μm
    D、>10μm

2、What are the dust classifications?
    A、Size of aerosol particles
    B、Light drizzle
    C、Respirable dust
    D、Normal atmospheric dusts

3、Nuisance dusts types including:
    A、Gypsum
    B、Kaolin
    C、Limestone
    D、Organic

4、Explosive dusts types including:
    A、Metallic dusts (magnesium, aluminum, zinc, tin, iron)
    B、Coal (bituminous, lignite)
    C、Sulfide ores
    D、Organic dusts

5、The natural atmosphere that we breathe contains not only gaseous constituents but also large numbers of liquid and solid particles.

6、Particles do not become visible to the naked eye until they are more than 100 microns equivalent diameter.

7、Mine dusts vary widely in shape, dependent largely upon the prevalent mineral constituents.

8、The interaction of small particles with light is not a sensitive function of particle size and the optical properties.

9、Dusts of ores of beryllium, arsenic, lead, uranium, radium, thorium, chromium, vanadium, mercury, cadmium, antimony, selenium, manganese, tungsten, nickel, silver.

10、The soluble salts of halite (NaCl) and( )can occasionally cause skin irritations, particularly around hatbands or tightly fitting dust masks.

Chapter 1 Assignment

1、What are the particle concentration types ?

2 Dust and Healthy

2.1 Silicosis随堂测验

1、Respirable crystalline silica is defined as particles with aerodynamic diameters less than ( )microns.
    A、10
    B、15
    C、20
    D、25

2、Chronic Silicosis: Usually occurs after ( )or more years of exposure at relatively low concentrations.
    A、10
    B、11
    C、15
    D、18

3、Accelerated Silicosis: Develops 20 years after the first exposure. Swelling in the lungs and symptoms occur faster than in chronic silicosis.

2.2 Coal Workers’ Pneumoconiosis (CWP)随堂测验

1、PMF is classified radiographically as category A, B, or C when large opacities with a combined area of ( ) cm or larger are found on the chest x-ray.
    A、0.1
    B、1
    C、10
    D、100

2、Since passage of the Federal Coal Mine Health and Safety Act of 1969, the Mine Safety and Health Administration (MSHA) enforces regulations designed to limit mine workers’ exposure to respirable coal mine dust to ( )mg/m3 or less if the silica content in the sample is less than 5%.
    A、1
    B、2
    C、3
    D、4

3、The rule also sets forth the mine operator’s obligations, including respirable dust sampling requirements for Part ( ) miners.
    A、10
    B、30
    C、60
    D、90

4、Workers in some aboveground coal mining operations also have increased exposure to coal mine dust.

2.3 Diagnosis and treatment随堂测验

1、Treatment types including: .
    A、Windblown dust
    B、Volcanic ash and gases
    C、Smoke and fly ash from forest fires
    D、Pollens and other aeroallergens

2、Natural sources include (but are not limited to): .
    A、Windblown dust
    B、Volcanic ash and gases
    C、Smoke and fly ash from forest fires
    D、Pollens and other aeroallergens

3、There has cure for these lung diseases, and they can be reversed.

4、A doctor may diagnose CWP or silicosis based on the combination of an appropriate history of exposure to coal mine dust or silica, compatible changes in chest imaging or lung pathology, and absence of plausible alternative diagnoses.

2.4 Dust in Atmosphere随堂测验

1、Particulates may also be classified by their origin: .
    A、Primary—emitted directly from a process
    B、Secondary—subsequently formed as a result of a chemical reaction
    C、Smoke and fly ash from forest fires
    D、Pollens and other aeroallergens

2、Natural sources include: .
    A、Windblown dust
    B、Volcanic ash and gases
    C、Smoke and fly ash from forest fires
    D、Pollens and other aeroallergens

3、These sources contribute to background values over which control activities can have little, if any, effect.

4、Nature sources cover a wide spectrum of chemical and physical activities and are contributors to urban air pollution.

Chapter 2 Exam

1、Silicosis that develops___years after first exposure to higher concentrations of silica dust.
    A、<5
    B、5-10
    C、10-15
    D、>15

2、PM10 is defined as particulate matter with a diameter less than or equal to ( )?
    A、10μm
    B、10cm
    C、10mm
    D、10nm

3、What are the the form of silica?
    A、alpha quartz
    B、beta quartz
    C、tridymite
    D、Normal atmospheric dusts

4、Diagnosis Methods:
    A、Chest Radiography
    B、Lung biopsy
    C、CT
    D、Pulmonary function tests and blood tests

5、Classification of silicosis types including:
    A、Chronic simple silicosis
    B、Accelerated silicosis
    C、Complicated silicosis
    D、Acute silicosis

6、Treatment of silicosis may include use of bronchodilators (medications to open the airways) or supplemental oxygen.

7、Treatment of silicosis may include use of bronchodilators (medications to open the airways) or supplemental oxygen.

8、PNF can occur in either simple or accelerated silicosis but is more common in the accelerated form.

9、Quartz is a common component of rocks; consequently, mine workers are potentially exposed to quartz dust when rock is cut, drilled, crushed, and transported.

10、A worker may develop one of three types of silicosis, depending on the airborne concentrations of respirable crystalline silica: (1)chronic slicosis(2) acelerated slicosis(3)( ) scosis.

Chapter 2 Assignment

1、If a sample contains 8% quartz, the reduced standard is? This regulation places the upper limit of exposure to respirable quartz is ?

3 Dust Sampling and Quantifying

3.1 Respirable dust samplers used in mining随堂测验

1、It consists of a constant-flow sampling pump, a size- selective cyclone, and a filter cartridge. For coal mining operations, the sampling pump should be calibrated to operate at ( )lpm.
    A、1
    B、2
    C、3
    D、4

2、If the gravimetric concentration was 1.3 mg/m3 over a 6-hour measurement period and the pDR average concentration was 1.0 mg/m3 for ( )-hour.
    A、1
    B、3
    C、4
    D、6

3、To determine the silica content of a gravimetric sample, the filter must be sent to an accredited laboratory for analysis.

4、The most common type of sampler used in the mining industry is the gravimetric sampler.

3.2 Sampling Strategies随堂测验

1、How do we take sampling strategies?
    A、To quantify the amount of dust liberated by a source
    B、The question of upwind and downwind of the source
    C、Difference
    D、Make a explaintion

2、Why do we take sampling strategies?
    A、Understand the dust source
    B、Know the quantity of dust
    C、Respirable dust invisible
    D、Effectively control the dust

3、To effectively control the respirable coal and silica dust exposure of mine workers, it is not necessary to identify the sources of dust generation and quantify the amount of dust liberated by these sources.

4、To quantify the amount of dust liberated by a source, dust sampling must be conducted in a manner that isolates the identified dust-generating source.

Chapter 3 Exam

1、The 10-mm Dorr-Oliver cyclone separates the oversize dust from the respirable fraction (usually considered to have an aerodynamic diameter of ( )or less).
    A、10μm
    B、10pm
    C、15 pm
    D、20 pm

2、PM10 is defined as particulate matter with a diameter less than or equal to ( )?
    A、10μm
    B、10cm
    C、10nm
    D、10mm

3、The most common type of sampler used in the mining industry is the gravimetric sampler.

4、To determine the silica content of a gravimetric sample, the filter does not need to be sent to an accredited laboratory for analysis.

5、Because of the great number of variables encountered in mining operations that can impact airborne dust levels, it is highly desirable to place multiple gravimetric samplers at a single location and calculate an average dust concentration.

6、The PHM is another real-time sampler that has been developed and tested by NIOSH, approved for use in underground coal mines by MSHA, and reached commercial production.

7、To effectively control the respirable coal and silica dust exposure of mine workers, it is not necessary to identify the sources of dust generation and quantify the amount of dust liberated by these sources.

8、To quantify the amount of dust liberated by a source, dust sampling must be conducted in a manner that isolates the identified dust-generating source.

9、In an underground limestone mine, samplers were placed in the immediate intake and return of an underground crusher to determine the amount of dust liberated during the dumping/crushing of the limestone.

10、For quantifying exposures for an operator of a more mobile piece of equipment, such as a haul truck in an underground gold mine, the use of a real-time sampler such as the PDM would be beneficial to quantify dust exposure from multiple sources.

Chapter 3 Assignment

1、What are the principle of operation?

4 Dust Explosion and Prevention

4.1 Explosion fundamentals随堂测验

1、Methane and air explosions occur in the well-known mixture range of 5% to ( )% methane in air.
    A、10
    B、15
    C、20
    D、25

2、Flaming combustion of all kinds is extinguished at oxygen contents of 10 to 12 per cent while smouldering is usually terminated at oxygen concentrations below ( )per cent.
    A、1
    B、2
    C、3
    D、4

4.2 Coal dust combustion and explosion随堂测验

1、The lower flammability limit may be of the order of ( )g/m3 with maximum explosibility at 150 to 350 g/m3 depending upon the volatile content of the coal.
    A、30
    B、50
    C、70
    D、100

2、To put these flammability limits into perspective, it should be recalled that threshold limit values for respirable coal dust concentrations can be as low as ( )milligrams per cubic metre.
    A、1
    B、2
    C、3
    D、4

3、Coal dust and methane are synergistic in their explosibility characteristics. The flammability limits of each of them are widened in the presence of the other.

4、The concentration of carbon dioxide then begins to fall as the oxygen concentration is depleted, moving toward 10. At this point, a truly fuel-rich condition exists.

4.3 Prevention practices and technologies随堂测验

1、Behind those seals are 900 feet of longwall shields, the shearer, the stage loader, three continuous mining machines, and three roof bolters, as well as( )million tons of reserves.
    A、10
    B、20
    C、30
    D、40

2、The relevant published literature offers a comprehensive review of the subject of mine fires and explosions.

3、Failure to take quick and proper action invariably leads to weeks, if not months, of imposed closure and the expenditure of many times the cost of an effective fire prevention, detection, and fighting program.

Chapter 4 Exam

1、The most energetic mixture, occurring at approximately ( )% methane in air, may produce as much as 5,200 kJ/kg of mixture.
    A、10
    B、15
    C、16
    D、17

2、Methane and air explosions occur in the well-known mixture range of 5% to ( )% methane in air.
    A、10
    B、15
    C、20
    D、25

3、The fire triangle including:
    A、Ignition sources
    B、Oxidizers
    C、Fuels
    D、Liquids

4、Classification of Liquid Fuels – Definitions including:
    A、Flash Poin
    B、Flammable Liquids
    C、Combustible Liquids
    D、Pulmonary function tests and blood tests

5、The function of autoignition temperature including:(
    A、Concentration of the vapor
    B、Material in contact
    C、Size of the containment
    D、Pollens and other aeroallergens

6、The less feared of hazards in underground mines or other subsurface facilities are those of fires and explosions.

7、Whenever a combustible solid or liquid is heated to a sufficiently high temperature (flashpoint), it will produce a vapour that is capable of being ignited by a flame, spark or hot surface which has the required concentration and duration of thermal energy.

8、The oxygen which forms the third side of the fire triangle is normally provided by the air.

9、Methane and air explosions occur in the well-known mixture range of 15% to 25% methane in air.

10、a normal range of Graham's Ratio should be established for any given mine. This will usually be less than( ) per cent.

Chapter 4 Assignment

1、Many regulations were related to fire, but talk about what and why were the most important?

5 Dust control in surface process industries

5.1 Basics of dust collector systems随堂测验

1、Particle sizes are typically measured in
    A、nm
    B、μm
    C、mm
    D、cm

2、The advantages of local exhaust ventilation systems?
    A、Capture and eliminate very fine particles
    B、No a detriment later
    C、Better performance in warm/hot weather conditions
    D、None of the above are correct

3、Dust collection systems are the most widely used engineering control technique.

4、Local exhaust ventilation system (LEV) is a positive pressure exhaust ventilation technique.

5、1mm=( )μm

6、The respirable dust is defined by those particles≤ ( ) μm size range

5.2 Airflow and dust control随堂测验

1、Air velocity is measured in feet per minute (fpm).

2、Air velocity doesn’t impact the size of particle.

3、Air quantity is measured in cubic feet of air per minute (cfm).

5.3 Exhaust systems design随堂测验

1、Hood types including:
    A、Enclosing
    B、Capturing
    C、Receiving
    D、Blowing

2、What are the most important parameters during the hood design?
    A、The rate of airflow through the hood
    B、The material of the hood
    C、The shape of the hood
    D、The location of the hood

3、Hoods only use exhausting ventilation.

4、What are the common constituent parts of exhaust systems?

5、( ) and ( ) are the two issues that need to be considered when determining the rate of airflow to a hood.

6、The range low velocity in ductwork is <( ) fpm, respectively.

Chapter 5 Exam

1、Particle sizes are typically measured in
    A、μm
    B、nm
    C、cm
    D、mm

2、The respirable dust is defined by those particles≤ ( ) μm size range
    A、44
    B、10
    C、70
    D、2.5

3、Hood types including:
    A、Enclosing
    B、Blowing
    C、Capturing
    D、Receiving

4、What are the most important parameters during the hood design?
    A、Airflow through the hood
    B、Material of the hood
    C、Location of the hood
    D、Shape of the hood

5、Common hopper waste discharge devices:
    A、Rotary Airlock Valves
    B、Double Dump Valves
    C、Tilt Valves
    D、Dribble Valves

6、( ) and ( ) are two methods for fabrics to collect particulates
    A、Depth loading
    B、Gravity loading
    C、Surface loading
    D、Centrifugal loading

7、Common types of dust collectors:
    A、Gravity separators (drop-out boxes)
    B、Baghouse collectors
    C、Wet scrubbers
    D、Electrostatic precipitators (ESPs)

8、Dust collection systems are most widely used engineering control technique.

9、Local exhaust ventilation system (LEV) is a negative pressure exhaust ventilation technique.

10、Local exhaust ventilation systems (LEVs) could only capture and eliminate coarse particles.

11、Local exhaust ventilation systems (LEVs) perform better in cold conditions.

12、Air velocity is measured in cubic feet of air per minute (cfm).

13、Air velocity impacts the size of particle.

14、Particles in >( ) μm size range could be seen by naked eyes.

15、A HEPA quality filter is one that is ( )% efficient at removing 0.3-μm particles

16、A practice that is becoming more prevalent in the industry is to refer to a fabric's dust removal efficiency by its ( ) rating.

17、The range of high velocity in ductwork is ( ) to 4500 fpm.

Chapter 5 Assignment

1、Please list the common types of dust collectors.

6 Dust Control in Coal Mining (1) – Longwall Mining

6.1 Dust distributions in mines随堂测验

1、Longwall mining equipment and operational practices have improved dramatically since the early .

6.1 Dust distributions in mines随堂测验

1、Longwall workers can be exposed to harmful respirable dust from only one dust generation sources.

6.2 Dust control in tunnels随堂测验

1、Respirable dust in the last open crosscut

6.2 Dust control in tunnels随堂测验

1、The following practices can help control respirable dust levels along intake roadways?
    A、Limit support activities during production shifts
    B、Apply water or hydroscopic compounds to control road haulage dust
    C、Use surfactants
    D、Increase coal production

6.3 Dust control in working/development faces随堂测验

1、over of all dust generated during mining

6.3 Dust control in working/development faces随堂测验

1、is the pincipal method of controlling respirable dust on the longwall face

6.3 Dust control in working/development faces随堂测验

1、Drum-mounted water sprays can sprays apply water for dust suppression

6.4 Alternate dust control technologies随堂测验

1、About of the dust generated on the longwall comes from the cutting action of the shearer drums

6.4 Alternate dust control technologies随堂测验

1、High-pressure inward-facing drum sprays is not the alternate dust control technologies

Chapter 6 Exam

1、About? of the dust generated on the longwall comes from the cutting action of the shearer drums
    A、30%
    B、50%
    C、70%
    D、80%

2、Respirable dust in the last open crosscut?
    A、0.42 mg/m3
    B、0.55 mg/m3
    C、0.62 mg/m3
    D、0.88 mg/m3

3、The following practices can help control respirable dust levels in the longwall shield?
    A、Canopy-mounted spray systems
    B、Shield sprays on the underside of the canopy
    C、Air dilution
    D、Unidirectional cutting sequence

4、Alternate dust control technologies
    A、Ventilated cutting drums
    B、Foam discharge from shearer drum
    C、Foam discharge from shearer drum
    D、Low-pressure inward-facing drum sprays

5、The characteristics of Longwall Shield?
    A、more powerful and faster/cutting speeds exceeding 100 fpm
    B、shield movement can be a significant source of dust
    C、coal and/or rock fall from the top of the shield canopy directly into the airstream
    D、requires shields to advance at a faster rate

6、Drum-mounted water sprays can sprays apply water for dust suppression

7、Respirable dust generated by outby sources can not enter the ventilating airstream and remain airborne across the entire longwall face.

8、The breaking of coal and rock in the crusher mix with the ventilating airstream

9、over of all dust generated during mining

10、Longwall workers can be exposed to harmful respirable dust from generation sources.

Chapter 6 Assignment

1、The practices can help control respirable dust levels in the longwall shear?

7 Dust Control in Coal Mining (2) – R&P Mining

7.1 Continuous Miner dust control随堂测验

1、For suppression of dust, close to the source is most effective

7.1 Continuous Miner dust control随堂测验

1、Continuous Miner dust control Methods include: dilute, suppress, redirect, or capture dust

7.2 Ventilation control随堂测验

1、The clean air is blown toward the face and sweeps the dust-laden air toward the .

7.2 Ventilation control随堂测验

1、The clean air sweeps the face, and the dust-laden air is then drawn behind the return curtain or through the to the return entries

7.3 Dust control for roof bolters随堂测验

1、Low airflow at the bit due to hose, fitting, and

7.4 Other practices随堂测验

1、When shuttle cars unload, dust levels can be decreased by using at the mouth of the feeder-breaker that activate during dumping to wet coal before it enters the crusher.

Chapter 7 Exam

1、MSHA lowers the dust standard below if the silica content of the sample exceeds 5% by weight in dust samples.
    A、5mg/m3
    B、8mg/m3
    C、10mg/m3
    D、2mg/m3

2、Continuous Miner dust control
    A、Water Spray System
    B、Dust rollback control
    C、Flooded-Bed scrubbers
    D、Ventilation Control

3、For suppression of dust, high flow at low pressure close to the source is most effective

4、The air-atomizing nozzles produce the best airborne dust capture and ofen use in mines

5、most operations are supplying quantities above the statutory minimum of in an effort to better control respirable dust and methane.

6、the scrubber should continue to operate for after coal cutting ends to allow the scrubber to capture dust remaining in the face

7、For redirection, is required

8、Continuous miner operator movement is restricted due to the need to be positioned in the discharge air at the end of

9、The air quantity provided by the line curtain should be limited to over the scrubber capacity

Chapter 7 Assignment

1、The best practices can help reduce dust exposure to the bolter operator?

8 Dust Control in Underground Stone and Metal/Non-metal mining

8.1 Crushing facilities随堂测验

1、is : Air is exhausted from under the plenum, creating an indraft at the crusher jaws to capture the dust. The dust-laden air is then directed to a nearby return

8.1 Crushing facilities随堂测验

1、Significant dust source:
    A、the dump
    B、the crushers
    C、the associated conveyor belts
    D、transfer points

8.2 Production shots随堂测验

1、In large mine openings, low air velocities ( ) are common because of the large open-space volume

8.2 Production shots随堂测验

1、The key design parameters should be included in the mine ventilation plan
    A、Permanent or brattice stoppings installed in key locations throughout the mine to more efficiently direct and control the airflow.
    B、Reaching concentrations as high as 0.1 mg/m3
    C、Booster fans to improve local ventilation
    D、A main mine fan used to establish air circuits on a mine-wide scale

8.3 Mucking operations随堂测验

1、Several dust control methods should be considered to lower airborne levels of silica dust
    A、Establish an air circuit and keep fans as close to the loading area as possible.
    B、Control haul road dust.
    C、Keep muck wet when loading
    D、Booster fans to improve local ventilation.

8.4 Drilling随堂测验

1、, incorporated into the drilling machine by the original equipment manufacturers, tend to be the most common type of dust control.

8.4 Drilling随堂测验

1、should be used to improve local ventilation

Chapter 8 Exam

1、silicotics among those with an average exposure of 0.025–0.05 mg/m3
    A、20%
    B、18%
    C、13%
    D、15%

2、Several dust control methods should be considered to lower airborne levels of silica dust
    A、Booster fans to improve local ventilation
    B、Control haul road dust
    C、Keep muck wet when loading
    D、A main mine fan used to establish air circuits on a mine-wide scale

3、In large mine openings, How air velocities are common because of the large open-space volume

4、Isolate the facility from the general mine air circuit is the methods for reducing exposure to silica dust.

5、Best practices for respirable silica dust control generated from three primary dust sources: (1) crushing facilities, (2) production shots, (3) mucking operations

6、Silica can account for over of the respirable dust sample by weight

7、90% of dust emissions with this type of system are attributed to , drill stem bushing leakage, and dust collector dump discharge

8、Diesel-powered propeller fans, because of their and entry coverage, have favorable ventilation characteristics for this application

Chapter 8 Assignment

1、Best practices for respirable silica dust control generated from four primary dust sources

9 Dust Control in Minerals Mining and Processing (1)

9.1 Wet Spray Systems随堂测验

1、What are the methods of control dust?
    A、Airborne dust prevention: prevent dust from becoming airborne
    B、Airborne dust suppression: knock down dust already airborne
    C、proper maintenance of equipment
    D、controlling droplet size

2、Air atomizing nozzles are sometimes called two-fluid nozzles because they inject compressed air into the liquid stream to achieve atomization.

3、Fines are , thus decreasing its ability to become airborne.

9.2 Drilling and blasting随堂测验

1、In order to obtain acceptable drill bit life, the water must reach the drill bit.

2、Two basic methods for controlling dust on drills are , .

9.3 Crushing milling and screening随堂测验

1、The most important consideration for dust control within a grinding/classification/product storage circuit is dust containment,and the second is dust collection.

2、, and can be major sources of airborne dust due to the inherent nature of size reduction and segregation processes.

3、Selection of crushers is based primarily on and .

4、Milling, often called , is a process by which granular minerals are reduced in size by compression, abrasion, and impaction.

Chapter 9 Exam

1、Screening operations can not produce high levels of dust.

2、Control of dust generated by these operations can be achieved with proper analysis of the sources, identification of appropriate control technologies, and consistent application and maintenance of selected controls.

3、Wet dust control systems can be very effective but are more costly to install and operate.

4、The drilling process is only used in underground mines for blasting operations .

5、Water separation can be achieved through the use of a water separator sub.

6、Dry drilling is accomplished without the use of water for dust control.

7、The purpose of the next two presentions is to for lowering respirable crystalline silica dust at mineral processing operations.

8、Fines are , thus decreasing its ability to become airborne.

9、The most commonly used spray nozzles produce , , or .

10、When water is used to control dust, it has only a limited due to evaporation, and will need to be reapplied at various points throughout the process to remain effective.

11、The drilling process is used in both surface and underground mines for which are conducted to fragment the rock.

12、, and can be major sources of airborne dust due to the inherent nature of size reduction and segregation processes.

Chapter 9 Assignment

1、Please list the keys to effective wet spray dust control.

10 Dust Control in Minerals Mining and Processing (2)

10.1 Buck loading随堂测验

1、To address the above dust emissions during bulk loading, a common control measure is to equip the loading spout with a dry dust collection system.

2、Another modification that can be made in an effort to reduce dust emissions during bulk loading is the utilization of the loading spout.

10.2 Conveying随堂测验

1、There are three primary root causes for fugitive dust emissions associated with conveyor belts:
    A、spillage
    B、carryback
    C、small dust
    D、airborne dust

2、Belt conveyors are among the most commonly used piece of equipment at mineral processing operations.

10.3 Secondary sources随堂测验

1、Workers performing maintenance can be exposed to higher than normal dust concentrations because the maintenance task may involve working in areas where dust controls are not functioning effectively, working on highly contaminated equipment, or the work may have to be performed in unusual nonroutine operating conditions.

2、The first strategy to lower dust exposures in any structure is to have an effective primary dust control plan that captures major dust sources at their point of origin, before they are allowed to escape out into the plant and contaminate workers.

10.4 Haul Roads, stockpiles and open area随堂测验

1、Barriers can not be effective in reducing the amount of windblown soil up to a height of 6 feet.

2、The mixes with the material to create a crust which can be resistant to wind erosion.

Chapter 10 Exam

1、In order to realize the dust control benefits of the discharge cone, the loading spout must be properly positioned to minimize the chance of dust escaping into the ambient air during loading.

2、For the most effective dust control and to prevent clogging of the loading spout, it is important that the spout position be periodically raised as the height of the loaded material increases.

3、A belt wash system sprays the conveyor belt with cement while simultaneously scraping it to remove the product.

4、Screw conveyors are totally opened except at the ends.

5、Skirtboards are employed to retain material on the belt after leaving the loading chute and until the material reaches belt speed.

6、At mineral processing operations ,workers can not exposure dust from contaminated work clothing.

7、The basic principle behind the total structure ventilation design is to use inside air to sweep up through a building to clear and remove the dust-laden air.

8、The four factors translate to the four dust control measures:Surface roughness,water,coatings,and wind.

9、The is designed to transfer product from a plant/storage container into the vehicle that will be used to transport the product.

10、During the bulk loading of product, dust contained within the product can be liberated and emitted into the ambient air as the product falls from the to the .

11、Proper selection of the correct type of equipment is a function of the specific application, taking into account the material to be transferred, , and nature of the transfer.

12、In almost all cases, a worker uses an to manually exhaust the product and dust into the collector system.

13、The most common method of dust control on haul roads is using with water being the most common.

Chapter 10 Assignment

1、The most prevalent location for material spillage is at transfer points. Material may be deposited virtually anywhere along a conveyor, but always leaves the conveyor at the head pulley. What are the four steps used in order to effectively control material at transfer points?

11 Dust Control in surface Mining

11.1 Drill dust collections随堂测验

1、is another drill dust collection method and involves injecting water into the bailing airflow traveling down the drill stem.
    A、Wet suppression
    B、Dry drill dust collection
    C、Dry suppression
    D、Wet drill dust collection

2、Dust generated by compressed air (bailing airflow) flushing the drill cuttings from the hole being drilled.

11.2 Cab filtration system随堂测验

1、Enclosed cabs with , , and systems are typically integrated into the drills and mobile equipment to protect the operator from the outside environment.
    A、heating
    B、ventilation
    C、drill stem
    D、air conditioning

2、Use an efficient respirable dust recirculation filter is one of the key performance factors for enclosed cab filtration systems.

11.3 Haulage road dust control随堂测验

1、Which is not the method of haul road dust control?
    A、surface wetting with plain water
    B、adding hygroscopic salts to the road surface
    C、adding films (polymers) to the road surface
    D、adding soil to the road surface

2、Off-road haul trucks used in the mining industry typically contribute less of the dust emissions at a mine site.

11.4 Hopper dump control随堂测验

1、Dust in the ore is released from the large volume of ore product being dumped in a long period of time.

2、Several effective control methods include enclosing the hopper dump using water sprays to suppress and contain the dust from rolling back out of the enclosure.

Chapter 11 Exam

1、Air filtration is often part of the as an engineering control for airborne dusts.
    A、HVAP system
    B、HVAM system
    C、HVAC system
    D、HNAP system

2、Dust emission reductions of greater than 63% were measured by the collector discharge dump after installing an extended shroud near ground level Maintain a collector-to-bailing airflow ratio of at least .
    A、1:3
    B、3:1
    C、4:1
    D、1:4

3、A is recommended to reduce the dust liberated due to rollback under the dumping mechanism.
    A、water spray system
    B、tire-stop water spray system
    C、local exhaust ventilation system
    D、tire water spray system

4、Many practical areas of engineering controls designed to mitigate exposure of surface mine workers to all airborne dusts, including silica, are:
    A、drill dust collection systems
    B、enclosed cab filtration systems
    C、controlling dust on unpaved haulage roads
    D、controlling dust at the primary hopper dump

5、Adding excessive water down the hole can cause operational problems with appreciable improvement in dust control.

6、Enclosed cab filtration systems are one of the mainstay engineering controls for reducing mobile equipment operators’ exposure to airborne dust at surface mines.

7、Enclosed cabs with heating, ventilation, and air conditioning (HVAC) systems are typically integrated into the drills and mobile equipment to protect the operator from the inside environment.

8、The most common method of haul road dust control is surface wetting with plain water, but others include adding hygroscopic salts, surfactants, soil cements, bitumens, and films (polymers) to the road surface.

9、Decrease distance between vehicles traveling the haul road can controll haulage road dust exposures.

10、A water spray system can be used to filter the dust-laden air from the enclosed hopper area.

Chapter 11 Assignment

1、What are the key factors for controlling dust from the primary dump?