摘要:
Method and apparatus for reducing the dustiness and increasing the size distribution of a coal product in a coal preparation plant by mixing dewatered coal fines and recycled fine coal from the cyclone separator with a binder to form an agglomerated/size enlarged coated product which can be passed through a thermal dryer.
摘要:
This is a method of producing manufactured aggregates from coal combustion by-products having sulfur. Recycle fines containing calcium hydroxide, an aluminum-containing material, and water are mixed together to form a feed mix which is agglomerated into an agglomerated product. The agglomerated product is combined with curing fines which contain calcium oxide which together form a blended mix. The blended mix is cured using the moisture in the blended mix which is used to exothermally hydrate the calcium oxide in the blended mix to form calcium hydroxide and which autogenically provides the required heat for curing and converts the calcium oxide in the blended mix to a dry calcium hydroxide-containing material to form aggregate products and dry fines. The aggregate products are separated from the dry fines, the dry fines are recycled to the mixing step and the aggregates are taken and used as a useful product for other purposes.
摘要:
A process for making high-strength aggregates including hydrating calcium oxide containing coal combustion ash for a sufficient period of time to convert a high percentage of the calcium oxide to calcium hydroxide prior to forming the aggregates and curing the aggregates in high humidity. The moisture of the hydrated material is monitored to vary the hydration moisture to the desired set point. Further, the process involves producing high-strength aggregates from calcium hydroxide containing FGD ashes such as generated from duct sorbent injection and spray dryer processes.
摘要:
In a froth flotation beneficiation, the rate of addition of collector reagent is varied in response to the change in particle size effected by the beneficiation, as determined by comparing a size analysis of solid particles in one of the separated streams with a size analysis of solid particles in the feed stream.
摘要:
A method of separating fine coal particles from refuse particles comprising the step of:(a) providing a coal filter cake(b) forming a slurry of fine coal particles, refuse particles in a liquid mixture comprising water and organic liquid,(c) contacting said coal filter cake with said slurry,whereby a major portion of said water and a major portion of said refuse pass through said filter cake and a major portion of said organic liquid and a major portion of said fine coal particles pass across the top of said filter cake.
摘要:
A rotary drum assembly includes separate agglomerating and hardening drums that are rotated independently of each other. The agglomerating drum has a generally cylindrical configuration with an inner cylindrical wall. A scraper is rotatably positioned within the agglomerating drum in spaced relation to the inner cylindrical wall with its axis spaced from the axis of the drum. The scraper has a tubular body portion with a plurality of parallel rows of blades extending radially therefrom. Each of the rows extends lengthwise along substantially the entire length of the scaper body portion and follow a helical path having a single turn about the axis of the tubular body portion. The rows of blades thus make a single convolution about the scraper body portion. Drive means are provided to synchronously rotate the agglomerating drum and scraper with the scraper arranged to rotate at a preselected and different speed relative to the speed of the drum. Agglomerative material is introduced into the rotating agglomerating drum and forms a layer of agglomerative material on the drum inner cylindrical wall. The scraper is rotated in the same direction as the direction of rotation of the agglomerating drum and at a preselected synchronous speed with the agglomerating drum. The rows of parallel blades on the scraper form a plurality of spaced elongated generally longitudinal ridges and valleys in the layer of agglomerative material on the drum cylindrical wall. The ridges have a slight arcuate configuration and form less than a single convolution throughout the entire length of the agglomerating drum. The spaced elongated ridges in the layer of agglomerative material extend lengthwise in the drum substantially parallel to the axis of the drum and serve as longitudinally extending lifters to mix and agitate other particulate agglomerative materials introduced into the drum by lifting portions of the other particulate agglomerative material from the underside of the bed and depositing the material on the upper surface of the bed. This type of mixing promotes the formation of agglomerates having a preselected relatively narrow size range. The synchronous rotation of the scraper removes agglomerative material deposited on the surface of the elongated ridges and valleys formed in the layer of agglomerative material so that the desired ridge and valley configuration is maintained in the layer of agglomerative material.
摘要:
The present invention is an improvement in the known process of making a coking feedstock from non-caking or weakly caking coals for slot-type coke ovens wherein the coal is subjected to solvent extraction; and at least the non-distillable extract in the effluent slurry product, after removal of part or all of the solvent, is mixed with carbonaceous solids to serve as a binder therefor. The improvement resides in the use of fluidizer char (which is produced by the low temperature carbonization of coal in a fluidized bed) as the carbonaceous solids. The fluidizer char is preferably mixed with the coal extract slurry (after removal of solvent) in a liquid state at elevated temperatures under pelletizing and non-carbonizing conditions. The pelletized product, after cooling and crushing, is suitable as part or all of the coking feedstock for coke ovens.
摘要:
Formcoke suitable for use in a blast furnace is made from a non-caking or weakly caking coal by converting the coal to an agglomeratable material consisting essentially of a blend of the entire product (without separation of extract and undissolved solids) obtained by solvent extraction of the coal in the presence of hydrogen and a suitable amount of hydrocarbonaceous solids. The agglomeratable material is agglomerated under low temperature carbonizing conditions and the agglomerates are thereafter calcined to produce strong formcoke.
摘要:
A process for producing a distillable hydrocarbonaceous stream, fuel gases and blast furnace grade coke from a heavy, high sulfur, crude oil by producing delayed coke from at least a portion of the crude oil; crushing at least a portion of the coke to provide a finely divided coke feedstock to a briquetting operation where the finely divided coke is briquetted using crude oil or topped crude oil as a binder to produce briquettes of a size from about 3/4 inch to about 3 inches with the resulting briquettes being passed to a high temperature vertical calciner where the solids are desulfurized to produce a strong blast furnace grade coke. The distillable stream and fuel gas stream are recovered from the delayed coking operation, the vertical calciner and optionally a crude oil topping operation. In some instances coke particles in the size range from about 3/4 inch to about 3 inches may be passed directly to the calciner without crushing and briquetting. However, it is preferred to crush and briquette substantially all of the coke.
摘要:
An improved method and apparatus for producing hardened carbonaceous agglomerates from a feedstock selected from the group consisting of finely divided coal solids, finely divided coal-derived solids and hydrocarbonaceous binders is disclosed.