Unlock instant, AI-driven research and patent intelligence for your innovation.

Energy-saving calcining method for increasing activity of coal gangue

A coal gangue and calcination technology, which is applied in the directions of climate sustainability, solid waste removal, sustainable manufacturing/processing, etc., can solve the problem of insufficient utilization or utilization of heat, reduce coal gangue processing capacity, and increase production costs. and other problems, to achieve the effect of fully flexible heat utilization, uniform and controllable temperature, and complete carbon combustion.

Active Publication Date: 2014-03-26
EAST CHINA UNIV OF SCI & TECH
View PDF9 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this calcination process with additives not only increases energy consumption, but also increases production costs
In addition, because the carbon content in coal gangue often varies greatly, the existing calcination process is generally unable to adapt to this. Therefore, in order to maintain the stability of the calcination temperature in actual operation, when the carbon content is low, it is necessary to mix coal for calcination, thereby reducing the unit. The amount of coal gangue processed by the calcination furnace within a certain period of time; when the carbon content is high, cooling devices need to be added to the calcination furnace to remove heat, and the generated heat cannot be fully utilized or the means of utilization are greatly restricted

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Energy-saving calcining method for increasing activity of coal gangue

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] Crush and grind the coal gangue with 4% carbon and 39.23% alumina until it is less than 120μm, and pyrolyze it at 550°C for 30 minutes. The temperature of the combustion furnace is 800°C, and the temperature of the secondary combustion furnace is 900°C; the leaching condition is to add 20% hydrochloric acid at a solid-to-liquid ratio of 1:4, and leaching at 90°C for 60 minutes, the alumina leaching rate is 87.95 %.

Embodiment 2

[0032] Crush and grind coal gangue containing 8% carbon and 38.22% alumina until it is less than 10 μm, and pyrolyze it at 600°C for 10 minutes. After leaching, the filtered and separated filter residue is mixed with an appropriate amount of coal and sent to the combustion furnace. The temperature of the combustion furnace is 900°C, and the temperature of the secondary combustion furnace is 1300°C; the leaching condition is to add hydrochloric acid with a concentration of 20% according to the solid-liquid ratio of 1:4, and leaching at 90°C for 60 minutes, the alumina leaching rate is 92.30 %.

Embodiment 3

[0034] Crush and grind coal gangue with 12% carbon and 35.37% alumina until it is less than 75μm, and pyrolyze it at 650°C for 15 minutes. After leaching, the filtered and separated filter residue is directly sent to the combustion furnace. The temperature of the secondary combustion furnace is 1000°C; the leaching condition is to add 20% hydrochloric acid at a solid-to-liquid ratio of 1:4, leaching at 90°C for 60 minutes, and the leaching rate of alumina is 90.23%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to an energy-saving calcining method for increasing activity of coal gangue, comprising the following steps of: (1) crushing, grinding and pyrolyzing the coal gangue; (2) performing useful constituent extracting and solid-liquid separation on material to be activated, putting the solid in a primary burning furnace to burn, obtaining gangue coke and generating high-temperature gas mainly comprising nitrogen and carbon monoxide; and (3) putting the gangue coke in a secondary burning furnace to continue to burn, obtaining solid product gangue ash and generating high-temperature gas mainly comprising the nitrogen and the carbon dioxide, wherein the heat generated in the steps can be fully and flexibly utilized. The method provided by the invention has the positive effects that: the activation of the coal gangue is not influenced by coal burning, the temperature in the furnaces is uniform and controllable, the calcining product is stable in quality and the activity of calcined coal gangue is increased; the coal burning is not restrained by the activation temperature, the burning temperature is adjustable and the heat is fully utilized; and the method has high desulfurization efficiency, no influence on the activation of the coal gangue, no pollution to environment and prospect of industrial popularization.

Description

technical field [0001] The invention relates to the technical field of solid waste recycling, and relates to the high value-added comprehensive utilization of coal gangue, in particular to an energy-saving calcination method for improving the activity of coal gangue. Background technique [0002] Coal gangue is solid waste removed during coal mining and washing. my country is a large coal-producing country, and the amount of coal gangue discharged is huge. By 2005, the cumulative storage of coal gangue in my country exceeded 3 billion tons. Large-scale consumption and high-value comprehensive utilization of coal gangue are severe challenges facing our country. More than two-thirds of coal gangue in my country is mainly kaolinite-based clay minerals, and Al in its calcined ash 2 o 3 The content can reach more than 40%, which is one of the very precious aluminum resources. [0003] In order to improve the reaction activity and increase the extraction rate, the current tech...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): B09B3/00C01F7/02
CPCY02P20/10
Inventor 乔秀臣司鹏于建国
Owner EAST CHINA UNIV OF SCI & TECH