An apparatus for spraying plastic foam includes two containers respectively adapted to hold a solution of a urea-formaldehyde precondensate in a first aqueous medium and a second aqueous medium including a catalyst which causes rapid hardening of the precondensate when the two aqueous media are mixed. A foaming chamber communicates with a source of compressed air and with one of the containers for dispersing the gas in the corresponding medium and for thereby forming a foam. A first conduit connects the foaming chamber to a mixing chamber, and a second conduit connects the other container to the mixing chamber. A third conduit leads outward of the mixing chamber and terminates in a nozzle orifice normally open to the atmosphere. The compressed air is used for conveying the foam and the medium in the other container to the mixing chamber for continuously mixing the contents of the mixing chamber and for conveying the resulting mixture outward through the nozzle orifice when the latter is open. When the orifice is blocked, a check valve in the first conduit prevents flow of the catalyzed mixture into the foaming chamber.
A method and apparatus for covering substrates such as landfills, sewage, contaminated soil, sludge deposits, compost piles and the like. A protein based solution, preferably mixed from a foam concentrate, is mixed with air in a foam production nozzle and then spread to an approximately uniform thickness over the surface of the substrate. In an alternative embodiment the present invention also relates to a method for providing a foam covering to substrates such as buildings and other natural and artificial structures to protect such substrates from adverse environmental conditions such as polluted air or water, insects, extreme hot and cold temperatures and toxic vapors or substances.
An apparatus for preparing a water-based air foam includes a mixing chamber for mixing two liquid components, and a nozzle which sprays the mixed liquid components toward a pair of screens within a compartment to produce a foam material. A portion of the first liquid component is diverted upstream of the mixing chamber and is sprayed by three nozzles into the compartment to continously wash away pre-gelled materials which might otherwise accumulate on a side wall surrounding the compartment.
A chemical foaming system for use in a floor cleaning machine has a foam generator and a delivery system upstream of the foam generator in communication with a source of pressurized fluid and a source of liquid cleaning solution. The delivery system delivers pressurized fluid and liquid cleaning solution to the foam generator. A dispensing system is disposed downstream of the foam generator for dispensing foam generated by the foam generator onto the floor being cleaned. The foam generator has a pair of independent foaming chambers in generally parallel flow relationship intermediate the delivery system and the dispensing system whereby a portion of pressurized fluid and liquid cleaning solution delivered to the foam generator by the delivery system flows into one of the foaming chambers. The remaining portion of the pressurized fluid and liquid cleaning solution delivered to the foam generator flows into the other foaming chamber. Each foaming chamber is adapted for generating a foam therein for dispensing onto the floor by the dispensing system.
A method of cleaning a hard floor surface with a surface maintenance vehicle including the steps of generating a foam-like aerated cleaning liquid, selectively conveying the foam-like aerated cleaning liquid to the hard floor surface and a scrubbing medium operatively coupled to the surface maintenance vehicle, scrubbing the hard floor surface with said rotating scrubbing medium and said foam-like aerated cleaning liquid so as to loosen soil from the hard floor surface leaving behind a soiled solution of cleaning liquid and soil, and removing at least a portion of the soiled solution from the hard floor surface through a fluid recovery device. Additional aspects of the present invention include devices for performing the cleaning method.
A cleaning liquid dispensing system for use in a mobile hard floor surface cleaner includes fluid conduit and fluid communication with a supply of cleaning liquid, a pump, and a flow restriction member. The pump is adapted to drive a flow of the cleaning liquid through the conduit. The flow restriction member generates a pressure drop in the conduit, thereby restricting the flow of the cleaning liquid therethrough.
