Elongated webs of paper, textile, non-woven, and the like are heated by gas-fired burners, and where the webs are porous the hot combusted gas is sucked through the webs to add to the heating action. Where the webs contain an atmosphere-contaminating substance such as a coating having a vaporizable organic solvent, a shallow layer of the burner's gaseous combustion products can be swept over the coated web face as it is exposed to the burner's heating, to flush off the vaporized substance in relatively concentrated form in a fraction of the gaseous products. The flushed off concentrate contains little or no oxygen so that combustible vapors are not likely to form explosive mixtures. Separating the flushed off vapor from the concentrate is also easier.
The present application is a continuation-in-part of application Ser. Nos. 292,167, filed Aug. 11, 1981; 297,081, filed June 30, 1981; 238,418, filed Feb. 26, 1981; 186,491, filed Sept. 12, 1980 (U.S. Pat. No. 4,378,207 granted Mar. 29, 1983;) 178,121, filed Aug. 14, 1980, and (U.S. Pat. No. 4,373,904 granted Feb. 15, 1983;) 952,332, filed Oct. 18, 1978, now U.S. Pat. No. 4,326,843. Of these, Ser. Nos. 238,418, 186,491 and 178,121 are in turn continuations-in-part of application Ser. Nos. 94,901 filed Nov. 16, 1979 (U.S. Pat. No. 4,272,238 June 9, 1981); and 20,079, filed Mar. 13, 1979, now U.S. Pat. No. 4,290,746.
A method and apparatus for painting highway stripes and other patterns on a road surface includes the steps of heating the road surface to be painted or treated with a protective coating to a temperature typically in the range of 150.degree. F. to 165.degree. F. Paint is applied in spray form, the resin and hardener ingredients being mixed preparatory to spraying by a spray head. The paint mixture is sprayed onto the heated road surface as soon after the heat treatment as is practical. The paint spray may be heated as it passes through the nozzle. Granulated glass beads may be dropped onto the paint coating to enhance absorption of heat energy by the paint. The spraying operation is followed as soon as practical by a post-heating operation which preferably achieves temperatures in the aforesaid range, the pre- and post-heating operations significantly enhancing the cross-linking and drying of the paint or other coating enabling substantially immediate use of the road surface by vehicular and/or pedestrian traffic. The energy levels and the heating units and their spacing from the road surface are adjusted to heat the road surface (and paint) to the desired temperature.
Process for manufacturing a flat composite plastic structure, for example a floor covering, comprising a textile web and at least one layer of a plastic, for example a polyvinyl chloride, on the reverse side or on the top side, which impregnates the textile web, according to which process: a) the textile web is made available, b) a plastisol is made available, c) the textile web is coated with a layer of plastisol, d) a radiant surface is obtained by combustion of a combustible gas in contact with a porous structure, e) the layer of plastisol is heated, using the radiant surface, in order to remove the volatile organic fraction of the coated layer and to cause the plastisol to gel, wherein the combustion of the combustible gas takes place under flameless, catalytic conditions.
A method and apparatus for treating sludge from a paint spray booth operation. The sludge from the spray booth is deposited onto a porous belt of a conveyor system to allow the water to pass through the belt where it is collected for discharge from the apparatus. The remaining residue is passed over a vacuum device positioned beneath the belt and is then carried by the belt through an oven comprising a series of infrared thermal reactors arranged in serial fashion over the belt. The sludge is passed continuously beneath the infrared reactors and is dried thereby so that the sludge leaving the apparatus is in a dried particulate form which may be readily disposed of and/or solid. Convection air is recirculated through the apparatus to preheat the incoming sludge, remove smoke and other contaminants from the oven, and provide the desired pressure condition within the oven to optimize the efficiency of the thermal reactors.
A method and system are used for simultaneously programming a group of erasable programmable read only memories (EPROMs) (11) originally set in the "all-ones" state, by routing (17-49) programmed bytes, bit by bit, to each memory site on each EPROM and blocking (48) or bypassing the programming steps where a programmed byte consists of all ones, thus saving the programming time that would be normally used to program "all-ones" sites. Each programmed site and the sites set in the "all-ones" state are verified (52) prior to the routing of subsequent programmed bytes.
A sludge drying apparatus (10) including a housing through which air is recirculated wherein makeup air forms an air curtain assuring recirculation of heated air. The housing (12) includes a receiving station (14) in which sludge (20) is deposited on a conveyor belt (18). The conveyor belt (18) moves the sludge (20) to a drying station (16) where infrared heaters (42) radiate infrared heat on the sludge. Air for drying the sludge circulates from a fan plenum (28) to an air supply plenum (24). Air from the air supply plenum (24) passes across the face of the infrared heaters (42), and is directed downwardly toward the sludge (20) in a belt passageway (30). Air is returned through a return air plenum (26) located below the belt passageway (30). Part of the air received by the return air plenum (26) is ported directly from the belt passageway (30) to the return air plenum (26). Additional air is received in the return air plenum (26) through first and second return air ducts (36) and (38) located at the entrance opening (32) of the belt passageway (30) and the exit opening (34) of the belt passageway (30). Ambient air flows into the first and second return air ducts (36) and (38) as well as the air received through the entrance and exit openings (32) and (34) of the belt passageway (30). Ambient air received in the return air ducts forms an air curtain effectively sealing the ends of the belt passageway (30).
