Pilot-scale testing of microbubble flotation

Technical Report · Wed Aug 01 00:00:00 EDT 1990

OSTI ID:5386318

Yoon, R H; Adel, G T; Luttrell, G H; Mankosa, M J

The main objective of this project was to demonstrate the microbubble column flotation process in a process development unit (PDU). The project was divided into several different stages. The first involved continuous bench-scale testing in order to identify the operating parameters which most strongly influence column performance. These included feed rate, countercurrent wash water rate, aeration rate, frother addition, collector addition and froth depth. Several tests were also conducted using different feed particle size distributions. Based on the results from these tests, several PDU-scale columns were designed and constructed. These cells ranged from 6 to 14 inches in diameter and were approximately 15 feet high. The second stage consisted of testing of the PDU-scale columns for the purpose of: (1) demonstrating the feasibility of the microbubble flotation process for producing superclean coal, (2) demonstrating the ability of the microbubble column to process refuse streams (i.e., cyclone overflow material), (3) comparison with conventional techniques for coarse coal flotation, (4) collecting scale-up data for the design of commercial-scale columns. In the final stage, a comprehensive scale-up procedure was developed based on the fundamental principles of flotation. Expressions were developed which describe the flotation rate constant, mean retention time, fractional air hold-up and column mixing. These relationships were incorporated into a scale-up procedure based on known principles of chemical engineering reactor design. PDU-scale test results were used to validate the scale-up procedure. 95 refs., 141 figs., 23 tabs.

• Research Organization: Virginia Center for Coal and Minerals Processing, Blacksburg, VA (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC22-86PC91274
• OSTI ID: 5386318
• Report Number(s): DOE/PC/91274-T2; ON: DE91012856
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL
FLOTATION
BUBBLES
COMPARATIVE EVALUATIONS
DESIGN
EQUIPMENT
FLOW RATE
MATHEMATICAL MODELS
PARTICLE SIZE
PROCESS DEVELOPMENT UNITS
PROGRESS REPORT
SEPARATION PROCESSES
CARBONACEOUS MATERIALS
DOCUMENT TYPES
ENERGY SOURCES
EVALUATION
FOSSIL FUELS
FUELS
FUNCTIONAL MODELS
MATERIALS
SIZE
010300* - Coal
Lignite
& Peat- Preparation- (1987-)