Michigan Sugar - Sebewaing, MI
Challenge:
Integrate a new Wet Electrostatic Precipitator behind a 1974 vintage coal fired boiler in order to control emissions to below MACT standards.
Scope of Work:
Southern Environmental, Inc. (SEI) designed an up-flow configured Wet Electrostatic Precipitator (WESP) system consisting of two independently energized chambers in one module, with a single electrical field in the direction of gas flow. All metal parts touching the gas stream were constructed with 2205 stainless steel. The new WESP design utilized the SEI patented membrane technology which minimized weight, cost and water consumption.
Project Duration:
PO Received: 11/26/14
Materials on site: 7/5/2015
Start up: 8/2015
Detailed Engineering in the following disciplines:
Structural
Mechanical
Electrical and controls integration
1/12 Physical Scale Model Study
Civil
Controls
Fabrication and Installation Services:
WESP Fabrication and Installation
Field Technical Support and Start Up
Access Fabrication and Installation
Electrical Installation
Civil Construction
Ductwork Fabrication and Installation
Project Management
Structural Steel Fabrication and Installation
Southern Environmental’s Solution:
Southern Environmental, Inc. provided a turnkey solution to engineer, supply and install a complete Wet ESP solution to ensure Michigan Sugar’s compliance with the MACT regulations and requirements. This unit is an up-flow configured Wet Electrostatic Precipitator (WESP) system consisting of two independently energized chambers in one module, with a single electrical field in the direction of gas flow. It was concluded that placing a WESP downstream of the existing wet scrubber would be the most technically and economically suitable solution for this plant. The up-flow design, by its inherent nature of being an excellent mist-eliminator, is a better configuration than the down-flow. The downflow configuration requires a mist-eliminator which is prone to plugging. The collecting electrodes are made out of felted polypropylene material which is irrigated continuously and uniformly with water. This continuous wetting minimizes the particulate build-up, down time due to intermittent flushing, and deposits of concentrated corrosives on dry areas. The dual chambers allow for one half of the WESP to remain in operation all the time thus increasing the reliability and uptime. SEI provided complete integration of the control, power and water systems as well as ducting and civil and foundation modifications in order to provide the most viable solution for Michigan Sugar.
Application / Operating Conditions:
Heat Input 120-150 MMBtu/hr
Maximum saturated flue gas volume at Outlet 85,000 ACFM
Flue Gas Temp at Scrubber Outlet 135-150 °F
Maximum Flue Gas Pressure +5 WC
Max particulate loading at Wet Scrubber Outlet 0.176 lb/MMBtu
Performance Guarantee:
With the boilers operating at or below the levels noted above, SEI guarantees that the filterable PM loading out of the new WESP system will not exceed 0.04 lbs/MMBtu. The outlet filtrable PM at time of performance testing was 0.0237 lbs/MMBtu.
