Bethlehem Steel Chooses Flo-Dar for Industrial Wastewater Monitoring

Bethlehem Steel Corporation, headquartered in Bethlehem, Pennsylvania, is the nation's second largest integrated steel producer. One of Bethlehem Steel's principle locations is the Sparrows Point Division located on the Chesapeake Bay near Baltimore, Maryland. Bethlehem's Sparrows Point Division has operations near Baltimore, Md., and in Coatesville and Conshohocken, Pa. In Maryland, about 4,000 people produce four million tons for cast steel slabs for hot-rolled and cold-rolled sheets, tin mill products, galvanized products, galvanized sheet and Galvalume sheet. 

The Sparrows Point facility includes a sintering plant, a large blast furnace, two basic oxygen furnaces with an annual raw steel production capability of about four million tons, a two-strand continuous slab caster, a 68-inch hot strip mill, a new cold sheet mill, continuous and batch annealing facilities, a galvanizing line, two Galvalume lines, a 48-inch hot-dip galvanizing line and tin mill facilities.

The processes associated with steel production create a great amount of wastewater.  Accurate measurement of this wastewater is important for Bethlehem Steel as they provide on-site treatment before discharging the flow into the Chesapeake Bay - one of the region's most important waterways.  

Prior to treatment the wastewater contains significant amounts of oil, grease, and iron particles.  Bethlehem Steel determined that submerged flow sensors would require regular cleaning.  This was determined to be both cost prohibitive and a generally unreliable means of providing constant monitoring.  

To achieve the needed accuracy and eliminate cleaning requirements Bethlehem Steel turned to Marsh-McBirney's Flo-Dar flow meter.  Flo-Dar uses two non-contact technologies to measure water velocity and water depth. 

• Velocity is measured using a state-of-the-art Doppler radar sensor.  This sensor very accurately measures the surface velocity of the flow.  Patented algorithms convert the surface velocity readings to average velocity.
• Depth is measured by a pulse-echo ultrasonic sensor.  depth is converted to area based on the channels size and shape
• Flow is then calculated by means of the continuity equation Q=V*A

The Bethlehem Steel Sparrow's Point Division prides itself on environmental stewardship.  Their environmental policy states very simply:

"We will comply with all environmental laws and regulations applicable to the conduct of our business. As a good corporate citizen, we are dedicated to the continuous improvement of the environment in which we all live."

To that end, according to the company, water coming in contact with the manufacturing process and requiring treatment before being discharged has been reduced by more than 50% over the last decade by new operational practices and recycling.