In order to make better use of tankers transporting oil from the oil-producing countries to oil-consuming countries, attempts have been made at transporting drinking water from the latter countries to the oil-producing. These attempts have been fruitless since it has been impossible to reduce the oil content to an acceptable value. By using a filter consisting of units (4) of foam plastic with perforated closed cells it has been possible to achieve values below that considered acceptable.

The present invention is a method of using crumb rubber from recycled tires as a filter media. The use of crumb rubber as a media differs from conventional sand or anthracite filters in several ways. The crumb rubber media is compressible which allows the porosity between rubber particles to decrease through the filter bed. The crumb rubber media compresses as headloss increases, allowing for better effluent quality late in the run. The crumb rubber media allows greater depth filtration. The crumb rubber media can be used at high filter rates, greater than 20 gpm/ft.sup.2. The crumb rubber media performs similarly to other traditional filter media in respect to turbidity and total suspended solids removal. The crumb rubber media properties are closely tied to media size and shape, with smaller media providing better effluent qualities and larger media allowing longer filter runs at higher flow rates.

Solid composition has an organic spill absorbing material in which is absorbed certain of a liquid organic compound or composition. The organic spill absorbing material can be water insoluble, particulate polymer particles that imbibe liquid organic materials. A halogenated organic can provide the liquid organic compound or composition. The halogenated organic can be a halogenated hydrocarbon. A fire can be fought by transmitting the solid composition containing a suitable flame retardant to the base of the fire under conditions such that the absorbed liquid in liquid or vapor form is released; and a living target can be stupefied by transmitting the solid composition containing a suitable stupefying agent under conditions such that vapors of the stupefying agent are released and stupefy the target.

An apparatus and method for treatment of waste water effluent includes a main conduit connected to a source of waste water, and a removable filter positioned within the main conduit, the filter having a light weight particulate material for filtration of the effluent. A drain field for filtration treatment of waste water effluent includes a source of waste water effluent, a main conduit in fluid connection with the source of waste water, and at least one in-line filter positioned within the main conduit, the filter having a light weight particulate material. The drain field may include at least one extension conduit connected in fluid communication with the main conduit and extending substantially upwardly therefrom, the extension conduit having a removable cap and a sensor to thereby generate a signal when water in the extension conduit reaches a predetermined level.

In a device for shutting off the flow of a fluid through a duct, preferably in a system for filtering drinking water, means for shutting off the duct comprise at least one obturator (14,22,35,43) disposed over a corresponding orifice (11) of the duct and means (15,23,36) for restraining the obturator (14,22,35,43) in a position such that the corresponding orifice (11) is not shut off, the restraining means being exposed to the flow of fluid through the duct and being able to undergo a change of state consequent upon the period of exposure to the flow in order to release the obturator (14,22,35) so that it shuts off the duct after a predetermined flow of fluid has taken place through the duct.