Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
  • B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
  • B03D1/00—Flotation
  • B03D1/02—Froth-flotation processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/06—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to wood
  • B05D7/08—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to wood using synthetic lacquers or varnishes
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/06—Wet spinning methods

Definitions

• Slush culm banks particularly bituminous coal
• Slush culm banks also tendto ignite and burn for years with serious annoyance from smoke and fumes.
• represented by the good coal in the culm or'other refuse are, of course, much more serious'in the anthracite industry than in the bituminous inin the breaker and I dustry, because the unit value of anthracite coal is higher than bituminous and the character of the anthracite coal results in greater degradation hence larger proportions of the slush culm.
• culm contains a mixture of materials varying both in size and in composition. That is to say, there is a certain amount of coal, for example about 60% in representative anthracite culms, which is very low in ash, containing less than 10% of ash and approaching the actual inherent coal ash for coalfrom that particular area. This good coal occurs in a wide range of sizes running from down to very fine particles less than 100 mesh (Tyler Standard Series). The accompany+ ing 40% of higher ash material, of course, grades c contaminated by any considerable portions of frommaterial with only slightly higher ash than also occurs in practically The losses emper even more difficult.
• the flotation ofcoal using standard flotation reagents which are for the most'part hydrocarbons such as kerosene accompanied, if necessary, by suitable frothers, is based on wettability of the coal by the oil and the'coal therefore tends to attach itselfto the froth bubbles and appears in the concentrate.
• the presentinvention is based on the discovery' that it is possible to floata full size range of refuse coalsuch as anthracite slush culm, with a very'small. amount of-reagents so that classified preferably by screening and the fine iii material which consists almost exclusively of fine high ash material, is rejected.
• the coarser material while it contains all of the coarse low ash coal, is still contaminated with a certain amount of coarse high ash material, and therefore screening of ⁇ the tailings will not recover the coarse coal in the form of a sufliciently low ash material.
• the oversize from the classification of the tailings can then be floated under conditions which will result in the flotation of coarse low ash coal particles and diniculties will not be encountered because the high ash material is all likewise coarse and therefore does not float oil into the concentrate and the problem of contamination with high ash material is solved.
• the present invention not only results in obtaining 25. better recovery of low ash material, but also results in an increased capacity of flotation equipment.
• the consumption of collector which is usually kerosene or a similar .hydrocarbon, is aiso ,decreased.
• the process of the invention is very flexible and is well adapted to handle refuse coal of difl'erent types to produce products for various markets.
• refuse coal of difl'erent types to produce products for various markets.
• there is a good market at a higher price for coarser coal sizes and it is desirable to keep the fine rougher concentrate separate from the floated coarse portion of the tailings.
• therougher concentrate may remain uncleaned-but where the minimum ash is required, it is desirable ,to clean the rougher concentrate as such aycleaning operation will greatly reduce the ash without material loss in good coal.
• the additional cleaning operation of the rougher concentrate necessitates additional flotation equipment .and slightly increases the amount of reagents.
• the particular compromise best suited for any given condition is largely determined by economic considerations and it is an advantage of the present invention that it is flexible and that the best and most profltabl compromise can be chosen.
• the invention will be described in greater ae-v areas-i1 tail in conjunction with the cleaning of anthracite slush culm from the bank orl current production of the Philadelphia 8; Reading Coal it Iron, Company. it should be understood that the exact details of flotation type, reagent consumption, and the like, will vary somewhat with difierent culm and with different coals, and the invention is therefore in no sense limited to the precise details of the specific examples.
• Example 1 Slush culm from the Locust-Summit Breaker of the Philadelphia in Reading Coal a Iron Company was floated in standard Fagergren flotation machines with .276 lb. per ton of a frother consisting of a mixture of paraffin alcohols or" 7 to 10 carbon atoms and stabilized With a hydrocarbon, and which is described in the patent of Christmann and Jayne No. 2,065,053 issued December 22, 1936, without any hydrocarbon collector. A concentrate was obtained which contained fine coal only, then the tails were classifled in the presence of 0.5 lb. per tonof sodium silicate and after rejection of the finer material5 lbs. per ton of kerosene were added to the residual pump at about 50% solids and the pulp then diluted to solids and floated in a second set of flotation machines.
• Iron Company having approximately 40% ash was floated at 21% solids in standard Fagergren flotation machines with .0322 lb. per ton of the frother described in Example 1.
• a rougher concentrate is obtained which contains the fine low ash coal.
• the remaining pulp is then screened at 28 meshand .092 lb. per ton of frother and 4 lbs. per ton of kerosene added to the"+28 mesh material.
• This coarse material is floated to give a second rougher concentrate, and both rougher concentrates are cleaned using .092 lb. per ton of additional frother in each case.
• the results obtained are shown in the following table:
• coal of frotmflotation size is intended to cover coal of a size passing through 10 mesh screens and'has no-other mean-- l ing. This represents about the coarsest coai which can be floated by a froth flotation process.
• a method of cleaning refuse coal which comprises subjecting therefuse coal of froth flotation size to'a froth flotation process with an 1 amount of reagent insufllcient to float flne high ash particles whereby a concentrate is produced containing a major portion of flne low. ash coal particles, classifying the flotation tailings, rejecting the fine sizes and subjecting the coarse particles.

Landscapes

• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Wood Science & Technology (AREA)
• Mechanical Engineering (AREA)
• Textile Engineering (AREA)
• Solid Fuels And Fuel-Associated Substances (AREA)

Priority Applications (5)

Applications Claiming Priority (1)

Publications (1)

Family

ID=22271796

Family Applications (1)

Country Status (3)

Cited By (6)

Families Citing this family (3)

• 1936
  • 1936-09-01 US US98975A patent/US2136341A/en not_active Expired - Lifetime
• 1937
  • 1937-08-17 GB GB22607/37A patent/GB482931A/en not_active Expired
  • 1937-08-17 GB GB22608/37A patent/GB493971A/en not_active Expired
  • 1937-08-30 FR FR826121D patent/FR826121A/fr not_active Expired
  • 1937-08-30 FR FR826120D patent/FR826120A/fr not_active Expired

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