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Environment VCM waste is not for burning Fluid-bed catalytic oxidation unit at Goodrich plant destroys waste hydrocarbons, saves energy and recovers chlorine B.F. Goodrich Chemical has turned its back on high-temperature incineration, a method that has been working well for destruction of hard-to-dispose-of chlori nated hydrocarbon wastes. It has switched, instead, to an in-house-developed fluid-bed catalytic oxidation unit to process the 25 million lbs./year of chlori nated hydrocarbon wastes generated at its l-billion-lbs./year vinyl chloride mono mer plant at Calvert City, Ky. And the company, which has been operating the new unit since July, has some impressive figures to support the advantages of the switch. Direct energy savings, based on com parison with the incineration system the company had been using, total 14 million Btus./hour. Moreover, the process, called Catoxid, recovers most of the chlorine value in the by-products. The process technology, which Good rich will license, offers other chemical companies that have chlorinated hydro carbon waste problems a new disposal al ternative. In the U.S., production of more than 10 million tons/year of chlorinated hydrocarbons for products such as vinyl chloride, chlorinated solvents and insecti cides, generates some 380,000 tons/year of wastes. And traditional routes--land dumping, ocean disposal and deep-well injection--have been almost completely closed by environmental control legisla tion. Until now, most companies have gone to incineration as an alternative disposal method. For example, Monsanto uses a John Zink (Tulsa) high-temperature unit to dispose of its polychlorinated biphenyl wastes at its Sauget, 111., plant. And the Hooker incinerator at Niagara, N.Y., can generate 2,600 F for destruction of chlori nated hydrocarbon waste streams. Dm rioodnch didn't want to merely destroy the unwanted hydrocarbons from its only VCM plant; its goal was energy savings and chlorine recovery. Meeting the Goal: Stanley Farbstein, the company's manager of energy and raw materials, reports that direct energy savings at the plant with the new unit are equivalent to 24,000 bbls./year of oil, and chlorine-value recovery indirectly adds savings of some 60,000 bbls./year of oil. The hydrogen chloride produced in the oxidation of hydrocarbon waste at the plant is equivalent to about 9,000 tons/year of chlorine, according to Farb stein. And since the Federal Energy Ad ministration estimates 38 million Btus. are required to produce a ton of chlorine, Goodrich figures energy savings of 342 billion Btus. from its chlorine recovery. Direct energy savings, compared with incineration, show a net advantage of 18,000 lbs./hour of steam. One of Two: Goodrich is the first to put a catalytic oxidation unit to use for chlorinated hydrocarbon wastes, but it is not the first to tout this type of system for the wastes. Lummus, which developed the Transcat process in 1971 for produc tion of vinyl chloride from ethane, has been offering it for chlorinated hydro carbon wastes and production of other chlorinated hydrocarbons, aldehydes, ke tones, acids and nitriles (CW, July 26, 1972, p. 61). A Transcat unit is due on stream in late 1975 at Shinetsu Chemical Industry's chloromethane plant in Naoetsu, Japan. Transcat uses molten salts of a multi valent metal (e.g., a mixture of copper chlorides) for three functions: as catalyst, heat-transfer agent and reactant In this system the waste stream is incinerated be fore the gas is contacted with the catalyst and air at about 600 F. Goodrich's Catoxid system is based on fluid-bed technology similar to that the company uses in oxychlorination units. The company, which has applied for pat ents and has licensing agreements pend ing, is not ready to disclose process de tails or the catalyst that is used. In the system, by-products from chlori nated hydrocarbon production are fed to a reactor. They enter at the bottom, where the mixture is fluidized with air. The air and chlorinated by-products react to form hydrogen chloride, carbon diox ide, carbon monoxide and water. Heat from the exothermic reaction is used to generate steam, which is fed to the plant's steam distribution system. Hydrogen chloride is returned to the VCM oper-. ation. Operating temperatures and pressures are "mild and moderate." The reactor con be made from "engineering alloys," according to John Elder, a Goodrich sen ior engineer. The only fuel used by the process is during startup operations, and the process economics do not require regeneration of the catalyst, he adds. Goodrich will not disclose cost details about the system. But Elder indicates there are substantial maintenance sav ings. `The incineration unit we had oper ated well, but it required a lot of mainte nance," he says. That unit was a Union Carbide system (CW, Apr. 19, 1972, p. 37), installed in 1969. "Very high temperatures (over 3,000 F) and the corrosive nature of the materials meant the unit wasn't simple to operate," says Farbstein. Construction costs are said to be com petitive with those for incineration units. A Carbide unit costs 5500,000 for each 2,000 lbs./hour of chlorinated hydro carbons to be processed. And a 28,000tons/year incineration unit built by Nittetu Chemical Engineering in the Nether lands cost some 53.5 million (CW, Dec. 6, 1972, p. 39). With the cost of energy soaring and chlorine in short supply, the Catoxid sys tem could prove valuable for producers of chlorinated hydrocarbons. And it could ease the cost problems of VCM makers who must revamp plants to meet strict air contamination standards within their plants as a result of the discovery of the VCM-cancer link. New curb on phosphates Air pollution emission standards for new phosphate fertilizer plants that were proposed last week by the Environmental Protection Agency are aimed chiefly at controlling fluoride emissions. Although fluorides are not on the list of pollutants for which national ambient air-quality standards have been set, EPA is acting to regulate them under a special procedure authorized in Section 111 (d) of the Clean Air Act of 1970. In the Federal Register notice about the new standards, EPA says the emphasis on fluoride control is necessary because "ex tensive documented evidence is available describing the injurious effects on vegeta tion and herbivorous animals" that con sumed vegetation contaminated by the fluorides. The regulations will require that phos phate fertilizer plants install high-effi ciency gas scrubbers. Visible opacity stan dards also are proposed for diammonium phosphate and triple superphosphate units and for storage facilities to control particulate emissions accompanying fluo ride gases. EPA estimates cost of controls at about 1% of sales for triple superphosphate and 0.5% for most other products. OCC 6536 November 6, 1974 CHEMICAL WEEK 31 Chemetron makes recarbonation pure and simple. Whatever recarbonation system you use, you need a continuous, adequate supply j And at low cost. f getting it now, take a look at our Cardox system. Th gas keeps coming. Fuel-burning C05 generators probably cause more recarbonation problems than any other single source. Which is a shame. You can get better results without them. Take the Cardox carbon dioxide system for instance. There's no on-site COa generator at all. Only refrigerated storage tanks to hold from 6 to 31 tons of liquid COj, and a pressure maintaining vaporizer. Combine this equipment with your flow control and diffusion components, and you have all the elements for a complete installation. Very basic, yes. But very effective. And there's no danger of downtime. The Cardox system rewards you with consistent, virtually maintenance-free performance. The gas stays pure. We're solving other water Cardox carbon dioxide is more problems, too. than 99% pure COa. Cardox C02 systems are used The clear, colorless liquid to neutralize caustic chemicals you get contains none of the in industrial waste, unwanted by-products you often water. Clean get from a COs generator. No Cardox carbon^ toxic carbon monoxide. No dioxide pro smelly, irritating sulphur duces milder, dioxide. No soot or smoke. more controllable It's so pure, in fact, that reactions than acids once you do. It leaves fewer inject it harmful impurities in the water. into water, it' It is less likely than acids to disappears overshoot the desired pH value. virtually And it's a lot safer to use, too. without a trace. But our researchers are Cardox maintenance and working right now to develop technical service backs it up. even more efficient ways to treat Our engineers are eager to help. water at low cost with Cardox If you don't know exactly carbon dioxide systems. So how large a unit to get, they'll when new techniques emerge, survey and rec you'll probably hear about them ommend the from us. proper size. It's a pure and simple fact. They'll even assist with recom mendations on auxiliary equip ment. And they can maintain your Cardox equipment for you. For more information, call your Cardox representative. Or write: Cardox Products, Chemetron Corporation, 111 EastWackerDrive, Cardox Products Chicago, Illinois 60601. Chemetron Corporation OCC 6537