Abstract: A toroidal chemical tablet with a close fitting water impervious peripheral barrier surrounding its sides with exposed upper and lower annular surfaces is disclosed. The tablet has a central hole to aid in water flow and dissolves inside out for even feeding. Also disclosed is a pool chemical tablet partially encased in a covering which when placed in a pool skimmer gives a visual indication when the tablet is substantially dissolved, as well as methods for using the tablet.

Abstract: A capsule and a method of making a capsule for use in the dissolution of a chlorine chemical compound into a body of water. The capsule comprises a tablet section having at least one chlorine compound tablet and a shell securely fitted about the tablet section. The shell has two apertures at opposite ends, each extension extending away from the tablet section and having a conduit communicating with an aperture to reduce the dissolving rate of the chlorine into the water. The ends of the extensions may be shaped to prevent the capsule from standing on its ends.

Abstract: A chlorine compound containing chemical tablet for dissolution into a surrounding body of water which includes an elongated tablet with length longer than thickness having an elongate central section connecting two opposing obliquely tapered ends along a longitudinal axis and an elongate tablet shell encasing the tablet having a corresponding elongate central section connecting two opposing obliquely tapered ends. The ends of the shell have openings therein and form an inwardly sloping and obliquely angled junction with the shell's elongate central section. The encased tablet lies in a skimmer unit on its side along a longitudinal axis and dissolves in a generally uniform and slow rate.

Abstract: A chlorine compound containing chemical tablet for dissolution into a surrounding body of water which includes an elongate tablet with length longer than thickness having an elongate central section connecting two opposing obliquely tapered ends along a longitudinal axis and an elongate tablet shell encasing the tablet having a corresponding elongate central section connecting two opposing obliquely tapered ends. The ends of the shell have openings therein and form an inwardly sloping and obliquely angled junction with the shell's elongate central section. The encased tablet lies in a skimmer unit on its side along a longitudinal axis and dissolves in a generally uniform and slow rate.

Abstract: A swimming pool chemical tablet and storage container is provided for use in a skimmer of a forced circulation flow system, the swimming pool chemical tablet having a radial sidewall contact surface which contacts the frusto-conoidally shaped sidewall of the container at a location at least equal to one-half the predetermined height of the tablet to form a tablet-sidewall flow space above the sidewall contact surface to control the rate of dissolution of the tablet when water is circulated in the forced circulation flow system.

Abstract: Chlorine-containing gases which may be formed in containers of solid chloroisocyanurates such as trichloroisocyanuric acid are adsorbed and decomposed by a gas scavenging agent consisting essentially of silica gel, an alkali metal bicarbonate, and carbon. The gas scavenger is preferably enclosed in a gas permeable spun-bonded polyolefin envelope. The scavenging agent adsorbs moisture, absorbs and decomposes nitrogen trichloride, removes chlorine, and neutralizes hydrogen chloride formed. The gas scavenging mixture is physically compatible and readily blended while minimizing dusting during packaging operations.

Abstract: A novel briquet is comprised of compressed hydrated calcium hypochlorite particles having a calcium hypochlorite content in the range from about 55 to about 75 percent by weight, a water content in the range from about 4 to about 10 percent by weight and a compression strength of from about 2 to about 95 kilograms. The briquets may be used in sanitizing water supplies as they dissolve slowly to release available chlorine at a controlled rate.

Abstract: An apparatus for dispensing and dissolving soluble water treatment materials is disclosed. The apparatus has an inlet, an outlet and a housing divided by a wall into an outlet chamber in fluid communication with the outlet and a dissolving chamber in communication with the inlet. A vertically adjustable control tube device for controlling the level of water in the dissolving chamber and an outlet valve device for maintaining the water level in the outlet chamber above the outlet are provided. A support device is provided to hold a plurality of cartridges with their lower ends immersed in the water in the dissolving chamber. A high water level malfunction shut-off valve with or without an indicator can be provided and the inlet flow can be controlled by perpendicular passageways with a rotary valve therebetween. The inlet may be in a wall of the outlet chamber and be isolated from the outlet chamber by an inlet valve mechanism leading to the dissolving chamber.

Abstract: Decomposition of chloroisocyanurates such as trichloroisocyanuric acid or alkali metal dichloroisocyanurates is inhibited by the presence of alkaline earth metal sulfates. The sulfates may be used in compositions with a solid chloroisocyanurate or they may be added separately, for example, to packages containing the chloroisocyanurate.

Abstract: Novel compositions comprising calcium hypochlorite and a proportion of a polyacrylic acid compound have been produced. the compositions provide accurately controlled concentrations of available chlorine to bodies of water such as swimming pools by reducing the solubility off the calcium hypochlorite. In addition, when employing dispensers for water soluble chemicals in treating very hard or highly alkaline water, inhibition of scale formation and prevention of scale build-up in the dispenser is achieved when the novel compositions are used.