Environmentally safe ultra-high pressure surface cleaning system
A method of ultra-high pressure surface cleaning. Water is first preferably filtered and de-ionized. The de-ionized water is pressurized to about 25,000 to 60,000 psi. The ultra-high pressurized water is applied to a surface, typically using a robot. The robot includes a vacuum for collecting water and debris removed from the surface. The stream leaving the robot will be an aqueous mixture of everything removed from the surface. The mixture next passes through a vacuum filtration unit, where most solids will be removed. Next, the mixture passes through a membrane filtration unit for removal of most remaining suspended solids. If toxic heavy metals are present, the mixture will pass through a heavy metal scavenger. After the foregoing treatment steps, the mixture will have less than 29 ppm suspended solids and be substantially free of lead and other heavy metals, rendering the mixture safe for surface water discharge in most cases.
1 . A method of cleaning a surface comprising:
pressurizing water to at least about 25,000 psi;
applying the pressurized water to the surface to remove foreign substances from the surface;
collecting a fluid mixture of the water and the foreign substances from the surface via vacuum;
transporting the fluid mixture of the water and the foreign substances to a first filtration unit;
removing a portion of the foreign substances from the fluid mixture in the first filtration unit;
transporting the fluid mixture to a second filtration unit;
removing a second portion of the foreign substances from the fluid mixture in the second filtration unit; and
passing the fluid mixture through a heavy metal scavenger in a fluid treatment system, wherein the heavy metal scavenger further comprises calcium polysulfide, whereby substantially all heavy metal ions present in the fluid mixture are removed.
2 . The method of claim 1 wherein the water is pressurized to between about 25,000 and 60,000 psi.
3 . The method of claim 1 wherein the first filtration unit comprises a dewatering vacuum container box.
4 . The method of claim 3 where the first filtration unit further includes a filter.
5 . The method of claim 1 wherein the second filtration unit comprises a membrane filtration unit.
6 . The method of claim 5 wherein the second filtration unit comprises at least two membrane filtration units provided in sequence.
7 . The method of claim 5 wherein the fluid mixture entering the second filtration unit includes suspended solids.
8 . The method of claim 7 wherein the suspended solids comprise less than 29 parts per million of the fluid mixture after exiting the second filtration unit.
9 . The method of claim 7 wherein the suspended solids comprise between about 4 and 15 parts per million of the fluid mixture after exiting the second filtration unit.
10 . A system for cleaning a surface, comprising:
a vacuum;
a first filtration unit;
a second filtration unit;
a heavy metal scavenger comprising calcium polysulfide; and
wherein the system is configured to:
pressurize water to at least about 25,000 psi;
apply the pressurized water to the surface to remove foreign substances from the surface;
collect a fluid mixture of the water and the foreign substances from the surface via the vacuum;
transport the fluid mixture of the water and the foreign substances to the first filtration unit;
remove a portion of the foreign substances from the fluid mixture in the first filtration unit;
transport the fluid mixture to the second filtration unit;
remove a second portion of the foreign substances from the fluid mixture in the second filtration unit; and
pass the fluid mixture through the heavy metal scavenger, whereby substantially all heavy metal ions present in the fluid mixture are removed.
11 . The system for cleaning the surface according to claim 10 , wherein the water is pressurized to between about 25,000 and 60,000 psi.
12 . The system for cleaning the surface according to claim 10 , wherein the first filtration unit comprises a dewatering vacuum container box.
13 . The system for cleaning the surface according to claim 12 , where the first filtration unit further includes a filter.
14 . The system for claim 10 , wherein the second filtration unit comprises a membrane filtration unit.
15 . The system for claim 14 , wherein the second filtration unit comprises at least two membrane filtration units provided in sequence.
16 . The system for claim 14 , wherein the fluid mixture entering the second filtration unit includes suspended solids.
17 . The system for claim 16 , wherein the suspended solids comprise less than 29 parts per million of the fluid mixture after exiting the second filtration unit.
18 . The system for claim 16 , wherein the suspended solids comprise between about 4 and 15 parts per million of the fluid mixture after exiting the second filtration unit.