electronics era; television is an important part of their lives. "Consequently," he says, "a combination of entertainment and education-is an excellent way to reach this audience." The audiovisual portion of the program features impressionist Frank Gorshin and sports personality Alex Karras. "We use many of the same visual techniques the networks do," Hoefs says. "Cuts, dissolves, animation, onthe-scene reports, and even commercials mix and blend into a fast-paced, information-packed program." Operators appreciate that approach, seeing it as a welcome relief from traditional "talking head" training programs. The course, which consists of 10 modules, can be tailored to a plant's individual situation. According to Nalco, most companies taking part in the program (which isn't free, by the way) use the introductory session, which covers the overall design and content of the program, the importance of the operator's job, and how it relates to the operation of the entire plant. Another section deals with maintenance and operation of the pretreatment system: lime-soda softening, filtration, zeolite softening, dealkalization, and demineralization. Others explain the feedwater system and the condensate system. Thefinalparts concentrate on the operation of the boiler itself. D
method provides an oxygen supply of more than 200 tons daily, and that the degree of biodégradation well exceeds 95%. Two radial-flow compressors with a power input of 4000 kw generate up to 4.2 million cu ft per hour of air at a pressure of about 1 atm. They are equipped with silencers and housed in a concrete building to reduce noise to a minimum. The operation is essentially free of odors, in the past a public nuisance that frequently accompanies the biological treatment of wastewater. Surface aerators in conventional systems agitate the upper level of the liquid, resulting in foulsmelling sludge aerosols being formed and carried some distance by wind from the plants. The subsurface aeration system in the new Hoechst unit circumvents this problem and also prevents accumulation of slime and sludge at the floors of the basins. Following biodégradation, the effluent passes to settling ponds where calcium hydrate and ferrous sulfate are added to promote sludge separation. Dewatering of the sludge is accomplished by forcing it through filter presses having an overall filtration area of 32,400 sq ft. The resulting claylike filter cake is used as landfill. Hoechst's latest water-treatment facility took two years to design and an additional two and a half years to construct. Uhde, the company's engineering subHoechst wastewater treatment unit saves space sidiary, collaborated in the project. Total Biological treatment plants for purifying Dr. Karlheinz Trobisch, who heads the cost amounted to nearly $30 million. The wastewater from chemical operations are pollution control department at Hoechst's fivefilterpresses and ancillary equipment in the dewatering unit alone cost almost not particularly new. Nevertheless, the Frankfurt operations. The new unit consists of five concrete $5 million. Hoechst management hopes latest unit that West Germany's Hoechst unveiled recently at its major chemical basins, each measuring 33 feet deep, 33 that some of the development costs complex outside Frankfurt has a number feet wide, and 264 feet long, and having a eventually might be recovered through of unusual features. And the company is combined capacity exceeding 1 million cu licensing of the system and through enspending considerable sums to further ft. A high-pressure air stream passes gineering contracts. This latest addition raises to 30 the adapt its bioengineering expertise to new, through a series of 1-foot-diameter pipes set about 5 feet from the floors of the ba- number of wastewater treatment facilities space-saving water treatment methods. Critical space limitations at Hoechst's sins. The pipes arefittedwith 240 aerators that Hoechst has installed. Of these, 16 100-year-old plant site, as well as the through which the compressed air passes are located in West Germany, and of the desire to cut down noise and odor, were into the surrounding liquid. The aerator others, three are in the U.S. In the whole key considerations in the design of the nozzles have spiral-shaped adapters that area of environmental protection, new effluent treatment unit. "We have, result in the airflow'screating consider- Hoechst A.G., the parent company, last for the first time, abandoned the cus- able turbulence in the surrounding liquid, year spent more than $43 million, 15% of tomary shallow basins, which usually are thereby promoting oxygenation. Hoechst its total capital outlay, according to Dr. equipped with surface aerators," observes engineers calculate that aeration by this Jurgen Schaafhausen, who is responsible for the firm's air and water quality activities worldwide. Globally, Hoechst invested $100 million last year on environmental control facilities. I Operating costs, too, are high, running at an annual rate of $100 million in West Germany, an increase of almost 250% from the 1970 level, and $133 million throughout the world. Capital expenditure and operating and research costs taken together amounted to about $214 million last year in West Germany and about $310 million if plants elsewhere are included. "This means that every day our company spends almost $1 million on environmental protection," Schaafhausen points out. Hoechst and Uhde engineers now are working on a novel bioreactor for wastewater purification, drawing on their expertise in fermentation technology. The New unit has basins 33 feet deep rather than the usual shallow basins what to do about those results. "And he should be motivated enough to actually perform the proper response, even if it's on the weekend, right before coffee break,' or at the end of his shift." But by and large, Hoefs continues, the boiler operator doesn't realize how important his job is. He doesn't see the connection between his work and the plant's overall success. "He's primarily concerned with a paycheck, with some hope of getting out of the boiler room, and with coping with day-to-day chores." Naturally, Hoefs adds, there are exceptions. But most operators are apathetic about any kind of training, seeing little value in it for themselves or their companies. On the basis of that profile, Nalco developed its program, stressing motivation—"this will make your job easier"—as well as training. The course is normally presented on-site by Nalco field representatives. Each lesson is divided into three sections. The first uses textbook material. The second consists of a videotape or film presentation, followed by discussion of the lesson. Finally, operators are given a "hands-on" explanation of how the lesson applies to their particular boiler system. Hoefs observes that many of today's boiler operators have grown up in the
May 15, 1978C&EN
19
unit they envision will consist of a cylin drical tank about 100 feet high and 20 feet in diameter. Injected air will be blended with the separately pumped sludge/water i(Ο mixture. A system of guidelines, similar ΖLU to those used in fermenters, will promote 00Ο circulation within the vessels. Aeration and sludge separation will be integrated within the one unit. Design and develop ment likely will cost $1 million before this second-generation wastewater biotreatment unit reaches the commercialization stage, Trobisch estimates. D
1
Single-cell protein pilot unit starts up Single-cell protein (SCP) is being pro duced in pilot-plant quantities in a new facility that Hoechst started up late last month at its chemical complex outside Frankfurt, West Germany. The 1000 metric-ton-per-year operation, developed by Hoechst and its engineering subsid iary, Uhde, with financial support from the West German ministry of research, involves specially designed continuous fermenter vessels and new technology (C&EN, April 24, page 18). Product will be offered as an animal feed supplement. A modification of the product might be suitable for human use. A decision whether to move into full-scale commercial production will await the outcome of the current round of evalua tions, which will take more than two years. However, Hoechst is prepared to license its process technology and knowhow to other companies that may be in terested. Methylomonas clara, the bacterium involved, is grown on a mixture of air and methanol containing ammonia, water, and other essential mineral nutrients. The dried product, which Hoechst tradenames Probion, contains some 70% protein, 10% nucleic acids, 8% fats, 7% mineral "ash," and 5% water. A purified version, from which essentially all the nucleic acids and fats have been removed, has a protein content of more than 90%, with minerals and water making up the balance. Called Probion-S, Hoechst expects this to be acceptable for human consumption. Its preparation entails new solubilizing and extraction methods for which the com pany has applied for patents. The development emerged from a broader research program in the general area of biotechnology that Hoechst has been engaged in since 1971 and for which the West German government is con tributing about $30 million. The new pilot plant cost nearly $10 million, with the research ministry footing 67% of the bill. The plant consists of two stainless steel fermentation vessels, each more than 65 feet high and each with a volume of more than 700 cu ft. Each can produce up to 1000 metric tons per year of product. "Having two fermenters that can be op erated independently . . . leads to flexi bility in our studies," points out Dr. Uwe 20
C&EN May 15, 1978
Faust: technique is superior
Faust, who supervises the pilot plant op erations. Product from the fermenters goes to a concentration unit. There, mechanical dewatering is aided by electrochemical coagulation. The concentrated material then passes on to a spray dryer. Liquid separated during the dewatering step is sterilized and recirculated to the reaction vessels. To make Probion-S, the SCP product first is dissolved at room temperature in a mixture of anhydrous ammonia and methanol. This breaks down its cellular structure and dissoves the liberated fat content. Filtration removes the fatty fraction leaving a homogenate of protein and nucleic acids. These are water soluble and can be separated from the protein by a simple washing step. This novel purification technique may be applied to protein preparations from any source, Faust says. It is superior to
conventional methods that have been in use until now, he adds. It avoids the use of alkaline treatment that can cause free amino acids to link together to form dipeptides like lysinoalanine, some of which have toxic effects. It is important that proteins for human consumption be free from nucleic acids, Faust continues, because these can pro mote development of undesirable physi ological conditions such as gout. Pro bion-S could find outlets in nutritive products like bakery goods, sausages, meat pastes, and soups, he believes. Pro viding protein concentrate to human diets is more sensible than adding it to animal feed, according to Faust, because about four fifths of it is lost in the animal's di gestive tract. Yet another extension of the current work involves partial hydrolysis of the protein to a soluble form. Hoechst scien tists have devised two methods to do this. One, using chemicals, still is under wraps. The other is a more expensive enzymic method. The soluble oligopeptides com prising 10 to 100 peptide units, precipitate in an acid medium. By use of appropriate exclusion nozzles, sheets or fibers of pro tein may be produced. The technique might be used for making sausage casings, texturized meatlike products, and other items for which there are potentially siz able markets. The conditions of hydrol ysis have been chosen carefully to avoid formation of certain peptides undesirable in foods because they have a bitter taste. Because of the extent of demand, arti ficially produced SCP will never fully re place soybean protein in animal feed, Faust says. Nevertheless, that they can be produced probably will tend to have a stabilizing influence on prices, which can fluctuate widely depending on the avail ability of soybeans. G
Gibbs Medal
Baker honored for widespread accomplishments Dr. William O. Baker, a chemist who made his mark in an electrically oriented company, likes to talk about the part nership between chemistry and electric ity. It's only been 150 years since Faraday first recognized that chemistry and elec tricity were closely associated in nature, he notes, and only 80 years since Thomson first proposed the electron. "It gives me a tremendous lift," he says, "to see that chemistry, based on the ideas of bonding and valency and reactivity through elec trons, has been the source of a major part of the materials for civilization. The ex citing thing—that I think hasn't been fully emphasized yet—is that electricity has done similar things in the same time, with a very high degree of interaction with chemistry." Baker is president of Bell Telephone Laboratories. This week, he will receive
the Willard Gibbs Award for 1978. The prestigious gold medal is awarded annu ally by the Chicago Section of the Amer ican Chemical Society "to publicly rec ognize eminent chemists who, through years of application and devotion, have brought to the world developments that enable everyone to live more comfortably and to understand this world better." The Gibbs Award was founded in 1910 by William A. Converse, a former secre tary and chairman of the Chicago Section. Svante Arrhenius was the first medalist. The roster of recipients includes such other notable names as Leo Baekeland, Marie Curie, Gilbert N. Lewis, and Roger Adams. Medalists are selected by a na tional jury of 12 eminent chemists from different disciplines. Baker received a Ph.D. degree in physical chemistry from Princeton in
