TACTICAL MOBILE WATER PURIFICATION UNIT WITH MODULAR, TRANSPORTABLE DECHLORINATION UNIT INPUT STAGE

Military forces require potable water in the field, and for any substantial deployment of troops it is conventional to provide water treatment facilities, usually mobile units carried by trucks or on trailers, which purify water that is then chlorinated and stored in large bladders from which the water is dispensed for use. Purified water is used for drinking water, medical needs, cooking and washing, etc.

A standard form of water treatment unit is known in the US Military as the Reverse Osmosis Water Purification Unit or by the acronym "ROWPU." The ROWPU employs successive levels of filtration and purification. In addition to filtration of large particulates and sediments, the ROWPU can eliminate organic and inorganic contaminants, toxic chemicals, heavy metals, and microorganisms such as protozoa, bacteria and viruses. This is accomplished mainly by the reverse osmosis or hyperfiltration process which forces raw (feed) water through very small orifice membranes. The purified water output from a ROWPU typically is chlorinated to prevent growth of pathogenic bacteria and viruses in the treated water. In the attached drawing, the ROWPU is a trailer carried self-contained filtration and purification unit.

The ROWPU defines a flow path passing a plurality of filtration levels, including filters for particulate material and also reverse osmosis membranes. The ROWPU has onboard water pumps and/or can be coupled to separate pumps that provide a differential pressure across the reverse osmosis membranes. The reverse osmosis membranes filter virtually to a molecular level (hyperfiltration), permitting water to pass through to a lower pressure side, and blocking impurities, ions in solutions and the like. The pumps provide for a flow to remove water on the high pressure side of the membranes, where impurities are relatively more concentrated as a result of the filtration. This water is discharged as effluent or stored as brine for further treatment. The output of the ROWPU is collected in a suitable receptacle and typically chlorinated to prevent later growth of algae or bacteria. In tactical deployments and the like, the typical receptacle is an expandable bladder tank.

The ROWPU is capable of purifying salt, brackish and fresh water for military needs. However, if one attempts to use chlorinated water as the input or source water to a ROWPU, the filtration elements will become damaged. Therefore, ROWPUs are used to purify water from unchlorinated sources such as natural watercourses, i.e., lakes, streams, ponds, and other sources of untreated water. They are used to desalinate ocean water as well.

URBAN DEPLOYMENT AND DISASTER RELIEF

In an urban deployment of troops, natural watercourses may be inconveniently located across populated areas from the sites to be used by troops. Thus, long connecting lines running from the watercourse to the ROWPU or from the ROWPU to the usage site may be required, or purified water must be trucked to forward positions presenting logistical problems for storage and distribution, potential opportunities for damage, sabotage or for adverse parties to inject deleterious materials into the water flow. In addition, many urban watercourses are polluted or otherwise may require special attention to water treatment steps. Similar considerations apply to disaster relief and humanitarian effort situations. In a natural disaster, water treatment and distribution infrastructures can be damaged and supplies made unavailable or contaminated. The ROWPU is also very useful in that case. Insofar as municipal water sources are available but of questionable integrity, however, the fact that they may contain chlorine precludes their use as source water by a ROWPU. It is standard and prudent military policy to treat water from any supply that is not completely within its control, in order to protect the troops. Thus, the military normally will refrain from the use of municipal water supplies when deployed, even when available because the treatment is uncontrolled and there is danger of contamination. Nevertheless, in an urban situation where municipal water is available nearby, it would be highly advantageous for tactical and logistical reasons the ROWPU would be able to utilize this water source.

CURRENT DECHLORINATION PRACTICE

No "field-friendly", cost-effective or environmentally responsible process or apparatus exists to enable a ROWPU to use a chlorinated water source such as municipally treated water. The free chlorine ions in the water destroy the reverse osmosis filter elements. Chlorine can be removed or dissipated by batch-treatment of tanks of chlorinated water using chemicals prior to pumping the water through the ROWPU. This is disadvantageous due to the need to handle and use chemicals, and the corresponding risk of exposure of operators and the environment to these chemicals. Alternatively, the water can be exposed to sunlight and the evaporation process time will cause the chlorine to dissipate. Both of these methods are both costly and inconvenient with respect to logistics and time.

RECORŪ AND ALL SOURCE CAPABLE™ ROWPU

The RECORŪ relates to the field of water purification, and in particular concerns modifying a mobile water purification system such as is used by military forces in the field, and is a transportable, modular input unit for dechlorination of water prior to treatment by reverse osmosis filtration equipment. This enables use of water that has already been processed and chlorinated, but is otherwise subject to suspicion.

The RECORŪ is a dechlorination apparatus that is optimally equipped for use to pre-treat chlorinated water prior to purification using a ROWPU, especially municipal water that may be of questionable integrity and requires purification, but also useful for other chlorinated sources such as the contents of swimming pools. It is durable, compact and light in weight, for easy transport and can survive deployment under adverse conditions. The RECORŪ is also versatile as to connection particulars as well as that it can be readily deployed and connected.

The RECORŪ allows a tactical water treatment installation to couple to municipal water supplies at fire hydrants, or to other sources of chlorinated water, to purify water that may have been contaminated by chemical or biological agents, or may otherwise be deemed insecure. It also provides a convenient and transportable water purification unit adapted to couple to the most readily available supplies of water, notwithstanding their chlorination, for use to provide potable water during emergency conditions such as natural disasters or humanitarian efforts.

The RECORŪ substantially improves the practical usefulness of the ROWPU, which is currently applied only to unchlorinated sources such as natural watercourses because chlorine damages reverse osmosis membranes. By adapting the ROWPU to purify chlorinated sources the RECORŪ allows a tactical water treatment installation or a temporary civil installation to couple to municipal water supplies at fire hydrants, swimming pools and other sources, to purify water that may have become contaminated or may have been tampered with by introduction of chemical or biological agents. Thus the RECOR PAK better adapts the ROWPU to deployment in populated areas where such infrastructure is substantially more accessible and generally useful than a suitable watercourse or other natural water source.

The RECORŪ (dechlorination unit) and the combination of the ROWPU with a RECORŪ extend the capability of military water treatment units to any source, including chlorinated water along with salt, brackish and fresh water sources, giving the ROWPU ALL SOURCE CAPABILITY™. In addition to removal of free chlorine, the RECORŪ PAK removes hydrogen sulfide, while reducing iron and certain heavy metals and can minimize biofilm buildup in the water carrying structures and on filtration elements downstream. As a result, the RECORŪ PAK extends the useful life of the ROWPU filter elements and reduces the need for maintenance and downtime. Thus the unit provides costs savings in hardware and man-hours while contributing to the readiness of the military and the civil defense authorities to respond quickly and effectively to needs for safe potable water.

RECORŪ - CHLORINATED PRODUCT WATER DISCHARGE APPLICATION