amount of air removed from the shelters aspiriruemyh
The amount of air removed from the aspiriruemyh shelters are determined partly by calculation and partly on the basis of empirical standards. The first attempts to justify the calculation of the volume removed by aspiration of air is mainly from transfers from the conveyor onto the conveyor and the unloading techek crushers were made Leningrad Promstroyproject and SIOT and Institute Mekhanobr.
In some guidelines and specifications, as well as in the SP 61 and SP 155 111 1960, data on aspiration membrane housings Troy. Featured obe.my exhaust air is not \ shgyvayu1 height elevatra. "W prippnnpalvvo not correct. In addition to the height of the elevator, the amount of air removed from the casing, also depends on the width of the bucket.
The processing of the available literature and experimental materials compiled in Table. 18, which shows the recommended amounts of air removed by aspiration from the dusty equipment. The table is compiled for the neutral dust, for which the coefficient - 1.
Given in the table do not claim an exhaustive parameter accuracy and completeness. In some cases, they should be changed in one way or another, in accordance with the construction of shelters, the composition of dust-raising material, and so and. We add that table. 18 drawn for the case when there is no guide roobespylivanns. If possible gidroobespylpvapnya volumes exhausted air can be lowered, and in some cases (hydrophilic material) rather zpachshelno. However, to say how much to reduce their aspiration for gidroobespylivanii, is difficult. Volume of air exhausted listed in Table. 18, are acceptable only if adequate containment equipment that is at the "normal" casing design and shelter.
In some cases, the amount removed from the shelter air is determined by calculation. Processing of materials listed in the SN 155-61, and also borrowed from other sources received by the calculated data and formulas, which give a satisfactory practical results. These data and the formulas set forth below, it is recommended to use in calculations of aspiration without hydro - dust control.
The amount of air removed from the aspiriruemogo shelter, L "is composed of the volume of air introduced into the shelter of the incoming material.:, And air prosasyvaemogo through leaks and openings of shelter, L. The general expression for determining the volume of air exhausted by the neutral dust write so:
L, [m / h]
The amount of air introduced into the shelter of the incoming material through the loading chutes, calculated by the formula
L3 = 0, \ 2K
To determine the volume of air introduced by the material in a capacious shelter screens PLI in the same shelter top jaw or cone crusher, when submitting material to the crusher or the roar of a plate or feeder can use the expression
L, - (0,2 -. 0,25)
When submitting material to the cover of a sealed process equipment IPT of the bunkers that have a residual layer of material, the volume of air introduced by the material, k, can be taken into account in the half size. When submitting material feeder speed vK should be 4-5 m / sec.
Volume of air, prosasyvaemogo through leaky shelter openings, defined by a certain formula
LH = 3600 / v
where F - the area of leaks and openings in the shelter m2;
v - the minimum design speed of air leaks and openings in m / sec (see Table. 18). Velocity v - an experimental quantity that depends on how and when gas hazards, the nature of dust in the shelter and the toxicity of the dust. For neutral dusts permissible concentration of 6 to 10 mg/m3 is recommended to take the velocity v (m / sec):
For shelters on conveyors that have no side-ventilated chambers (usual cover with sealing flaps), when you receive material from the conveyor or screen and exit the material from the crushing volume of air is recommended prosasyvaemogo calculated by the formula
LH =- DIA [m 3 / h], (60)
where A - coefficient depending on the conditions of receipt of material sent from a pipeline or the roar of A = 500, admission of the grinders N = 750, C - coefficient depending on the width of the tape, B - width of the conveyor belt in m; Mu - factor depending on the type of shelter, shelters for the no-go My-1, for bulkhead Moo = 1.4. The coefficient C are listed in Table. 19.