to liquid land application of digested sludge and increasing fuel costs for
transporting liquid waste have caused numerous problems for Wastewater
Treatment (WWT) Plants across the country. Flo Trend® Systems of Houston,
Texas, offers solutions to these problems with a low maintenance, low cost
Sludge Mate® that will dewater sludge to a level suitable for mechanical
Guadalupe Blanco River Authority (GBRA) spent two years accessing the cost of
removing digested sludge from their WWT Plants. In the past, all solids were
removed wet by vacuum trucks and transported to a private grass farm for land
application. During the wet season, the grass fields were off limits for liquid
applying. In addition to difficulties with handling and distribution, fuel
costs continued to rise.
reviewing several options, GBRA elected to choose the Sludge Mate — a
particular type of container filter. The biosolids are pumped directly through
Flo Trend Systems Poly-Mate Mixing and Injection System to flocculate the
waste. The Poly-Mate incorporates Flo Trend’s patented Mix-Mate that produces
uniform flocculation of the sludge. Once the material is flocculated, it passes
directly into the Sludge Mate. In less than 24 hours, the dewatered sludge is
suitable for transporting and spreading. The discharge water drains back to the
headworks of the plant or to the digester. After the sludge meets the paint
filter test, the Sludge Mate is transported to contracted grass fields. The
sludge is now mechanically spread using a manure spreader.
currently uses four 30-cubic-yard Sludge Mates at four WWT Plants near Seguin
and New Braunfels, Texas. In less than two months of use, the Sludge Mates has
significantly reduced the total suspended solids in the aeration basins. During
this period, the total concentration of solids was reduced from 9,800 mg/L to
4,600 mg/L. Due to the volume reduction achieved by the Sludge Mates,
transportation costs have greatly decreased; now solids are being hauled, not water.
Mates also eliminate problems caused by wet weather field conditions; because
they are enclosed, they can operate in rain or shine.