Total Coal Yard Manual Washdown System With Water Conservation Management
Situation
This 1690 MW plant was looking for an efficient and effective way to eliminate the dust buildup and potential explosion hazards. Running on PRB Coal, this issue is always top of mind. Their current housekeeping routine of hosing down all areas was working but was time-consuming. To clean one of 13 coal handling buildings required several men, one to one and a half days to complete the job. To save on O&M costs, keep with best practices and ensure governmental regulation compliance, they decided to install a manually operated washdown system.
Existing Problems
The service water supply for this plant is pulled from the cooling lake on their property which is replenished by pumping water from the nearby Colorado River. The water balance was the main problem as the plant can take out only so much water at a time. The system needed to be designed to run at 200 GPM to accommodate this demand.
Benetech Solution
Benetech provided the Engineering/Procurement/ Construction (EPC) of a 200 GPM manual washdown system in 13 coal handling buildings. The systems are installed throughout the entire coal handling system, from the Rail Car Dumper to the unit trippers. Each building was engineered for efficiency and operator convenience by splitting the spray zones so the system can be operated while reclaiming fuel. To accommodate the 200 GPM limit, Benetech installed a 3” block valve in the service waterline of each building. From there, it was routed through a 3” duplex basket strainer to all zone valves through a 2-1/2” galvanized mainline. The customer requested a manual system because they wanted operators to watch what was happening during the wash-down cycle.
Solution Achieved
Utilizing the new wash-down system, each of the 13 buildings can be washed down in one hour with only one employee to complete the job. In addition, the plant uses 30%-40% less water than when using a fire hose, meaning less impact on sump pumps, drainage systems, and related settling ponds. The result is significant savings in O&M costs.
The facility is now significantly cleaner throughout but with particular notice in the high bay building and other hard to access areas due to wash-down capability being installed at every location. With less PRB Coal dust left behind, the result is a safer environment. As a bonus, additional savings are realized with a cut in insurance costs received when Benetech installed the system.
