OUTLOOK
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Killing two birds with one stone: co itrolling emissions as well as increasing prod ict yields Molecular sieves ( M s ) , those naturally occurring zeolite crystals first named by Swedish mineralogist Baron Cronstedt some 200 years ago, have made milestones in chemical technology. Aside from commercial applications, such as the petroleum and petrochemical industries, they are also versatile in the mundane. These adsorbents can dry refrigerants, air space in dual pane windows, and the natural gas in our ovens, and scavenge moisture from metal-based paints and polyurethane floor coverings. In this age of pollution awareness and stress on industrial emissions control, i t would be timely to adapt these sieves to tail-gas cleanup and recovery.
Ms processes Union Carbide has come up with three systems-PuraSiv S (SO2 removal), PuraSiv N (NOx removal), PuraSiv Hg (mercury removal)-for treating gaseous effluents. The key element in its processes is the molecular sieves or molecular sieve/adsorbent blends, synthetic crystalline metal aluminosilicates which are highly porous adsorbents for water, some liquids, and gases. When these sieves are exhausted,
they can be regenerated by heated purge gas. The same basic equipment-usually two fixed bed adsorbers with sequenced valves for switching the beds from adsorption to regeneration-is factory- or fieldfabricated and skid-mounted for all three systems. There are no secondary waste disposal problems since gases are recycled and result as increased product. The PuraSiv S process is claimed to clean up 100 ppm process SOs from sulfuric acid manufacture. Sulfur dioxide is adsorbed from sulfuric acid plant vent gas, driven off by purge gas during regeneration, fed back to the acid plant, and converted to sulfur trioxide, and finally to sulfuric acid. This abatement complies with new EPA source performance standards (NSPS) for new plants-4 Ib S02/ton acid produced, or approximately 300 ppm SO2; and existing plants-5-10 Ib S02/ton acid or 500-700 ppm SOz ( E S & T , Oct. 1972, p 884). I t also increases sulfuric acid yield 2 4 % . The PuraSiv N process removes at least 50 ppm NO, from nitric acid plant tail gases. Nitric oxide (NO) tail gas is catalytically converted to nitrogen dioxide (N02) in the presence of oxygen also in the gas stream. NO2
is adsorbed, desorbed, and recycled to the acid plant. Increased acid yield is 2.5%. This treatment is in accordance with NSPS for new plants -3 Ib NOx/ton acid produced, or 209 ppm NO,; and existing plants4-7 Ib/ton acid or 500 ppm NO,. The PuraSiv Hg process recovers elemental mercury from hydrogen and end box seal air in chlorine industries. I t can also be applicable to mercury ore furnace stack gases, vent streams of laboratory glassware calibrating stations, and vent gases of battery disposal or incineration operations. The equipment for this process differs slightly from the S and N processes. In addition to the adsorber and heater, the hydrogen-cleansing system, for example, includes a blower, and chiller/demister. In a typical chlorine plant application, hydrogen is compressed in the blower, cooled in a chiller/demister to form water and elemental mercury condensates. The recovered mercury is returned to the chlorine plant for reuse. while the hydrogen passes through the adsorber. Remaining mercury in the hydrogen is preferentially adsorbed, released by a blast of hot gas, recycled through a demister, and recovered. Emission standards for chlorine plants have been 2.2 Ib/ day of Hg (hydrogen plus seal air streams) in the atmosphere regardless of plant size. For a 300-tpd chlorine plant, PuraSiv Hg promises effluent mercury levels averaging less than 60 ppbV, translated as 0.2 lb/day mercury from combined hydrogen and seal air streams. Ms performance A PuraSiv S unit went on stream at the 200-tpd sulfuric acid manufacturing facility of Coulton Chemical (Toledo, Ohio), on February 4, 1973. The acid plant is of the spent type, feeding a mixture of alkylation spent acid and refinery hydrogen sulfide off-gas. Normally, during start-up, following shutdowns for routine inspections and maintenance, during upsets such as power failure and fluctuations in hydrogen sulfide supply-virtually, at all times, the unit has maintained 99+% S O z recovery from vent gas
f Product acid arlcl has kept S O n daily effluent concentration at 15-25 ppm. Equivalent daily SO2 emission rate is therefore less than 0.4 Ib S 0 2 / t o n acid, one tenth of NSPS limits. The stack has been absolutely clear. PuraSiv N unit has been installed at Hercules' 55-tpd nitric acid plant in Bessemer, Ala., scheduled for start-up last month. Increased acid yield is expected to be 2.5% with NO, emissions less than one tenth of the federal standards. The 55-tpd Holston Army Ammunition Plant (Kingsport, Tenn.) will also begin using PuraSiv N in 1974. The Army and EPA will jointly evaluate the system. PuraSiv Hg has been performing well at Sobin's 180-tpd chlorinecaustic plant (Orrington, Me.) since August 1972. Daily mercury emissions in the 2 mft3 hydrogen stream at Sobin is less than 0.05 Ib. again
much less than federal standards. Another PuraSiv unit will be installed on seal air by the third quarter this year as a consequence of the adequate control demonstrated on the hydrogen stream.
Does it pay? Total investment including offsites-cooling tower, electrical substation, new instrument air compressor-was $397,000 for Coulton's 200-tpd sulfuric acid plant. For a 500-tpd sulfuric acid plant, total would run $1,150,000. This figure is based on SO2 in tail gas concentration of 3000 ppm and tail gas flow rate up to 30,000 scfm. The PuraSiv S unit operating costs per year for the 500-tpd plant are $60,900 for power (lc/kWhr), S12,500 for cooling water [4g ptg (per thousand gallons)], $16,000 for indirect heat (51 million Btu/day,
Primaw cooler
Demister
Feed effluent from decomposer Blower
H,O
+ Hg liquid
Heater
Recycle
Product gas
11
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Regeneration
Adsorption
mrnmmmrnum~~m~eamm
Battery limits
90c/million Btu), and $63,000 for molecular sieve replacement (every 3 years). Labor cost is zero for the fully automatic system. Credit for increased acid production is $88,200/ yr, at $15/ton acid produced. These expenditures add up to a net treating cost of $64,20O/yr, or 37g/ton sulfuric acid produced, representing the maximum treating cost since the adsorbent performance is guaranteed. Understandably, total treatment costs are considerably lower for new plants. Approximately 20% savings can be expected over add-on PuraSiv units. The capital cost for a skid-mounted PuraSiv N system is about $755,000 for a 300-tpd nitric acid plant. Yearly operating costs, based on NOx in tail gas concentration of 3000 ppm and tail gas flow rate of 24,000 scfm, would run $33,600 for power ( l e / k W h r ) , $11,800 for cooling water ( 4 ptg), ~ $13,500 for heat (43 million Btu/day, 90c/rnillion Btu), and $23,000 for molecular sieve replacement (every 3 years). Labor cost is again zero. Acid credit would be $60,200 at $20/ton acid. Net direct treating cost comes to $21,70O/yr or 2 l c / t o n of 100% nitric acid. Total installed cost for the PuraSiv Hg at Sobin's 180-tpd plant was $1 00,000. Operating costs have been offset by mercury recovery at 1.5 Ib/day, yearly, valued at greater than $2000 following current market price.
Buying insurance The PuraSiv processes are by no means inexpensive. I t is not economically feasible, for example, to use the S unit for SO2 from public utility stacks. or the N unit for NOx from fossil fuel-fired steam generators. But they are the best bet 'or plants where the off-gases can ue recovered as increased product yield. LCG Volume 8, Number 2, February 1974
107
Ozonation seen ming of age Predictions voiced at the organizing meeting of the International Ozone Institute indicate a rosy future for this process of sewage and water treatment The long-in-coming International Ozone Institute finally has been established. And if proponents of this method of water purification and waste water treatment are correct, it's going to make a difference. The institute was formed at its First International Symposium & Exposition heid in Washington, D.C., in December. The international group will serve as a focal point for information and technology transfer. It will collect and disseminate information, support research activities, seek applications for the use of ozone, and serve as a general data bank for all aspects of ozone technology. In addition, it will conduct conferences, forums, symposia, and workshops; publish newsletters,. bulletins, and other data; and develop educational materials. Ozone has long been used in Europe and Canada to treat drinking 'water, but interest in its use in the U.S. on a large-scale basis, especially to treat sewage, is relatively new. its benefits are that it disinfects by killing germs and viruses. It also is inexpensive enough to be used on a large scale, and does not leave a chemical residue in the treated water. Perhaps as important as anything else, when used to process drinking water, the water tastes good. What then are the drawbacks? This is debatable, it was affirmed at the Institute meeting. However, mention was made of the fact present sewage and water treatment technology in the U.S. is set up mainly for chlorine treatment, and the equipment changeover would be costly. Also, the generators that produce the ozone require energy, which apparently will continue to rise in cost. Other drawbacks include the possibility of explosions, which was discounted, and the recontamination of the purified drinking water if it must pass through diity delivery pipes before being consumed. Formally, the process has not been approved for human use by the U S Food and Drug Administration, but its safety is in no way doubted. The general consensus at the meeting, however, was one of optimism, according to Rip Rice, a Wash108
Environmental Science & Technology
be located in Waterbury, with Browning managing it from a business and operational standpoint. Rice will handle publication and information liaison assignments through his office here in Washington, Browning told ES&T. Sewage treatment
Rip Rice To operate Washington, D.C. branch
ington consultant who, along with Myron E. Browning, president of the Environmental Protection Research Institute (Waterbury, Conn.) was the prime catalyst behind setting up the meeting. In addition, Rice said, correspondence since the symposium has been heavy, especially among foreign attendees, and general interest is high. He said European members are making plans to organize into a subgroup. AS agreed upon at the symposium, the group's world headquarters will
Myron Browning To manage Waterbury head office
Rice says the big potential use for Ozonation in the U.S. will be in the area of sewage treatment rather than in treating drinking water. One reason is present antipollution laws. We can drink chlorine, or at least small amounts of it, but we cannot dispose of large amounts of elemental chlorine into streams because of its lethal effect on aquatic life. Another factor is that Americans are used to the chlorine taste, and do not mind it as much as the Europeans do. He points out that Frenchmen have been bitterly opposed to chlorine ever since World War I when it was used against France as a poisonous gas. Although chlorination, strictly speaking, is less expensive than ozonation, the use of elemental chlorine has resulted in problems and additional costs, which Rice says must be taken into consideration when comparing overall costs. For example, New York City prohibits the presence of elemental chlorine within its city limits. The response to this by city officials has been to switch to hypochlorite, which is more costly, Rice said. The large Blue Plains treatment plant in Washington, D.C., does use elemental chlorine in treating sewage; however, it has had io construct special underground vaults to store the chemical. The cost of this construction should be added to the overall cost of chlorination, Rice points out. Rice feels that the proposed new sewage treatment plant for suburban Montgomery County, Md., which probably will be located at Dickerson, would be a logical choice for a prototype ozonation operation. He said this especially would be true if the decision were made to remove the chlorine residual prior to dumping the waste water back into the waterways. In this case, he said, ozona-
tion could advantageously be used, and it would be cheaper. Jain S. Jain presented a paper at the meeting along with Michael A Sweet and Nicholas L. Presecan, all of Engineering-Science Ltd., (Cleveland, Ohio) that considered postaeration of the chlorinated and dechlorinated effluent. Postaeration has been necessitated in that state by an Ohio Environmental Protection Agency rub ing that limits what could be dumped into its rivers. Jain said he found that the cost of ozonation generally to be higher than chlorination. However, the cost of ozone production is normally cheaper using oxygen as a feed gas as opposed to using simply air, he said. His study also confirmed that ozonation leaves a large amount of dissolved oxygen in the final effluent, eliminating the necessity of postaeration. Taking into account the additional Cost of postaeration and the anticipated cost of dechlorination, Jain reported that the chlorination process was no longer attractive from a cost point of view.
Ozonalion in France The French have been using ozonated drinking water for some 65 years, and confirmed in 1968 when Compagnie Generale des Eaux opened what is still the largest such facility in the world at Choisyle-Roi, outside Paris, that the process is economical on a large-scale basis. The highly automated, $27.5million plant can take in up to 2450 gal of raw water per second from the Seine River. This plant can produce a total capacity of 800,000 meters3 of ozonated water per day. The Compagnie Generaie des Eaux and its affiliates serve more than 16 million users throughout France. The volume of water sup-
plied each year is more than 1 billion meters3 or 265 billion gal. The company is a private one, established by an imperial decree on December 14, 1853, with a view to helping municipalities with their water distribution. Their operations have since expanded considerably, .and now include a whole range of water supply systems throughout France. They vary in size from the complex in Paris with 4 million users to the small system at Saint-Malo de Beignon, Morbihan (Brittany) with 720 users. How it works As to the technology of a typical ozone process, three key inputs are involved: the air, or oxygen: an electrical current: and the raw water to be treated. The air usually is first passed through an air filter, blowers, a refrigerative unit, and an adsorptive air dryer to condition the air prior to ozonation. A transformer is used to step up the voltage to produce a corona in the air supply, and a contact chamber or ozone tower is used to effect the transfer of ozone from the gas phase to the water phase (see diagram). The contact chamber itself must serve to maximize three aspects of the operation-the effective inter-
Ozonalors. Large ozonators such as these will be much more in demand i f the process is implemented in this country on the Scale seen by many
face, the driving force or concentration differential, and the time of exposure with due consideration of advantages to be gained by countercurrent operation. Other factors to be considered are whether droplets of water shall fall through a column of rising ozonized air, or whether bubbles of air shall be injected into a column of water flowing in the same or opposite direction. In addition it must be deoided whether the air shall be injected into the entrant water or into the ozonizing tower itself. Finally, it must be decided whether mixing other than that inherent in the air-water streams shall be provided by mixing devices. In the process at the plant at Choisy-le-Roi, the water is first scrubbed with ferric chloride and other chemicals. Then the heavier particles of dirt are allowed to settle to the bottom of tanks while lighter particles are removed by filtering. The ozone is produced i n 12 large stainless steel ozonators. Here dried, refrigerated, and pressurized air is bombarded with up to 20,000 V of electricity to produce the ozone. When the ozone is pumped into the water tanks, millions of tiny bubbles explode into action. After about 12 min of very agitated reaction, the water flows into a distribution system throughly purified.
The challenge The future-of ozonation seems assured, if the European experience tells us anything at all. Compagnie Generale des Eaux has plans to install the world's largest ozone machine in a plant in Moscow at a cost of $5 million. In addition, agreements have been signed to build major new plants in Singapore, Brussels, and Syria. Elsewhere, Canada already has 20 smaller facilities in operation, Japan has 21, and Great Britain has four. The U.S. has only begun to operate plants using the process. One of the few that can be pointed to is located in Whiting, Ind. But if predictions voiced at the meeting are realized, before long, ozonation will be used to treat sewage and possibly even drinking water. WSF Volume 8, Number 2. February 1974
109
Diaaina into mine waste u w
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Literally mountains of problems need to be tackled
so that the slag heap spread can be contained When we speak of "the world's oldest profession," no doubt we mean mining, since its origins are lost in antiquity. In the U.S., mining activities now affect approximately 13 million acres, about 0.5% of the total U.S. land area. Of this total, 7 million have been undercut, 3 million disturbed by surface mining, and 3 million given over to mining-related waste accumulations. According to the Interior Department, by the year 2000, 30 million acres will be so affected if steps to alleviate the situation are not taken now. Mining-related environmental pollution, however, affects a much wider area than 13 million acres, particularly if its origin is a "nonpoint" (broad area) source, rather than a "point" source (from specific discharge pipes or stacks, or very small solid waste piles). In mining operations, water pollution and solid waste are the worst offenders; air pollution is less direct and more diffusely distributed. Mine drainage Because of aquifer and stream disruption, both coal and hard rock mines give rise to water pollution from mine drainage. The most objectionable is acid mine drainage caused by oxidation of exposed iron pyrites to ferrous sulfate and subsequent hydrolysis to sulfuric acid. Further oxidation of ferrous sulfate to ferric sulfate increases chemical oxygen demand (COD), and forms "yellowboy" (colloidal ferric hydroxide), as well as more sulfuric acid by hydrolysis of iron sulfates. Sulfuric acid in mine drainage can be neutralized or reduced by passage through calcium- or magnesium-containing formations, or by reaction with mica, feldspar, or clay, in which the acid is affected by potassium, aluminum, and silicon oxides in complex association. Potassium oxides will neutralize some acid; so will aluminum oxide which will form aluminum sulfate. However, aluminum sulfate hydrolyzes to restore some of the acid. Moreover, aluminum ions in any appreciable quantity are detrimental to aquatic life. 11 0
Environmental Science & Technology
Not all mine drainage is acid; mine discharges passing through strata containing little or no iron may be alkaline or nearly alkaline. Types of mine drainage and their chemical makeup are shown. Other sources of water pollution include runoff from spoil banks and refuse piles, which contain sediment and leachates and, in some cases, radioactive matter. Additional pollution may stem from fertilizers and pesticides used to restore fill for strip-mined land by vegetative means, and from indirect sources, such as cave-ins of abandoned mine shafts. Tailings All types of mines contribute heavily to solid waste production through removal of overburden and disposal of mine tailings after mineral values are extracted. This solid waste is not only unsightly, but can be hazardous in numerous ways. First of all, a pile of mine spoil can slide with disastrous results in populated areas. Second, wind action can pollute the air with "fines" carried from tailings piles. Third, in the case of coal mines, waste piles containing organic matter can smolder for protracted time periods, poisoning the air with thick smoke. I t requires monumental work and expense to extinguish coal mine waste fires. Cleaning the old mine brook In some mines, such as phosphate or oil shale mines, water plays an integral part in the mining process; in coal mines, by contrast, water is
largely an unwelcome guest. Be that as it may, mine water must be cleaned, preferably at the source, before it is discharged to the environment. In mining activities which require water, recycling may curtail water discharge to some degree. In coal mines, however, where water has little use, recycling is not considered. Where water is not recycled, present technology concerns itself mainly with treating water emerging from mines. In the coal industry, hydrated lime treatment of acid mine drainage is generally deemed to be the "best practicable technology" in compliance with P.L. 92-500, the Federal Water Pollution Control Act Amendments of 1972. Consolidation Coal Co. (Consol), for example, has built 19 mine drainage treatment plants in Pennsylvania, Ohio, and West Virginia since 1967. According to Consol, stream quality recovered to the point at which recreation and fish stocking once more became possible. Consol's capital costs were almost $200,000 at its most sophisticated treatment plant of three recently built in southwestern Pennsylvania, and $150,000 at the simplest plant. Capital recovery costs per annum come to $22,000-29,000, Costs for lime are $12,000-64,000 a year, depending on how much acid must be treated; it can run as high as 5400 ppm at some sites. To treat mildly acid water, Consol incurred costs of $0.13/1000 gal; for highly acid water, $0.72/1000 gal. Other methods of water pollution control (wpc), however, are being
Mine drainage classes Partially oxidized discharges Acid
PH
Acidity, mg I. CaCO. Ferrous iron, mg/l. Ferric iron, mg/l. Aluminum, mg/l. Sulfate, mg/l.
2-4.5 1000-15,000 500-10,000
0 0-2000 1000-20,000
Source: Environmental Protection Agency.
neutralized and/or
3.5-6.6
Oxidized and neutralized and/or alkaline
0-500 0-1000 0-20
6.5-8.5 0 0 0 0
500-10,000
500-10,000
0-1000
Neutralized oxidized and not
6.5-8.5 0 50-1000 0 0 500-10,000
Plan view of longwall stripping system
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half million dollars have been spent on environmental studies for this oil shale project (of over $24 million for total development) since 1964. Recycling, nonetheless, may still apply to mine tailings. For example, the solid component of Florida phosphate slimes proved useful for tile and brick making. Near Kellogg, Idaho, a 4-mile section of 1-90 was built with mine spoil, which can even be used to construct small, safe earth dams. Certainly, reseafch will turn up new uses; the raw material is cheap, so transport and processing costs, as well as markets. will determine commercial feasibility of making useful products from recycled tailings.
Healing deep cuts
examined, and these run the gamut from chemical treatment to deep well injection, sealing off mines, deep mine backfilling. reverse osmosis, electrodialysis, evaporation, freezing, and where useful, infiltration prevention. Costs vary; for example, sealing boreholes or fracture zones can run $100-1200 per hole; sealing shafts, $7000-25,000 per shaft; reverse osmosis, $0.68-1.05 in capital costs per gal per day, plus $0.50-0.70/ 1000 gal operating costs. Many other methods have not yet been evaluated as to capital and operating costs.
Leveling those mounds Coal and hard rock mining activities, underground and strip, cover about 3 million acres with solid waste piles. The tailings problem will certainly be aggravated as oil shale operations expand. Tailings are not only a major eyesore, but are a source of dust pollution in air, sediment and leachates in water, and danger from slumping. Fortunately, the public and private sectors have been training their guns on this problem for some time, especially since the mid-1960's. The immediate problem with spoil piles is to stabilize them against dusting and slumping. This problem
is approached by physical (proper grading, spreading, wetting). chemical, or botanical (anchoring by vegetation) means. Another approach is to find uses for which mine tailings may be a raw material. In this respect, for example. anthracite mine refuse (culm dump) material may be an asset. I t found use at Ashley, Pa., where. after a culm dump fire was extinguished and fine clay removed, the material from the dump provided good highway antiskid material for winter use. In the case of oil shale mining, Atlantic Richfield Co. (ARCO) is seeking the best way to dispose of 400 million tons of spent shale over 20 years at a 4500-acre mining property at Parachute Creek, Colo. This spent shale will accumulate at 66,000 tpd to produce 50,000 bbl/day of shale oil by the TOSCO I I 900°F retorting process. While spent shale shows promise for cement and asphaltic concrete, demand in western Colorado will not be great, and shipping to other points will render it uneconomical, ARCO therefore plans to process the used shale as a growing medium for grasses and brush after it is disposed of in a 700-ft deep hanging valley, and properly graded. Two and a
Strip mines for coal and other mineral values have long been the industry's rebuff to rural beautification programs. However, mine we must, but filling exhausted strip mines with urban solid waste or mine spoil, properly blended with other materials. will help to restore strip-mined land to near-original contours. Indeed, this has been done in Maryland and Pennsylvania; filled land has actually proved suitable for use as state parks in Pennsylvania. New approaches to surface mining are also called for. The West Virginia Surface Mining and Reclamation Assoc., under an EPA grant, developed "longwall stripping" to minimize environmental disturbance and ease restoration. The land is quickly backfilled to original contour. The terrain must be suitable; usually hill and valley, level, or isolated elevation. In some cases, underground mines are filled in to cut down cavein or underground fire hazard, as well as to dispose of solid waste. In fact, a disastrous abandoned coal mine fire, under what is now 1-81 near Scranton, Pa., was controlled in just such a manner.
Some food for thought Our answer to the fuel squeeze may be found mainly in what can be mined rather than pumped. I f concrete concerted plans as to what to do with the monstrous amounts of mine waste to be produced are not forthcoming, very possibly, state and local authorities in the affected regions could curtail or forbid mining activity. Indeed, the governments of Colorado and Wyoming have already expressed deep concern. over potential oil shale waste. I f these mining activities are inhibited because of fear of environmental disturbance, or the effects thereof, our vast energy resources might as well be in Antarctica for all the good they would do JJ us. Volume 8, Number 2, February 1974
111
How much metal is there in our waters? The amount can be precisely determined, but a lot must still be learned about the effects! In late November 1973, the news came out that the giant Chisso Corp., a major Japanese chemical producer, would pay $8 million in damages to fishermen at Minamata, Kyushu, southern Japan. I t had been charged that Chisso's plant at Minamata contaminated marine fish with organic mercury compounds, thereby nc3 only depriving the fishermen of their livelihood, but subjecting them to the dread Minamata disease. Between 1956 and 1973, three outbreaks of this frightful disease hit Japan at Minamata, Niigata, and Ariake. Allegedly, 45 people died in the Minamata outbreak, and more than 2000 were poisoned. Even as of the summer of 1973, more than 850 persons in Japan were known to have Minamata disease. This number will increase several times, said Tokyo University's Jun Ui, who spoke at the International Conference on Heavy Metals in the Aquatic Environment (ICHMAE), sponsored by Vanderbilt Univ., and others, and held at Nashville, Tenn., late last year.
Minamata symptoms Minamata disease affects people who consume large amounts of fish and seafood (or, in some cases, grain) contaminated with organic mercury compounds, especially methyl mercury (MM). Minamata victims show symptoms such as reduced visual acuity, loss of feeling, and hypertension in the earlier stages. As the sickness advances, the patient experiences polyneuritis, mental deterioration, inability to coordinate, and, ultimately, death. Other body parts, as well as the central nervous system (CNS), can be af112
Environmental Science & Technology
fected. Disease symptoms. in some cases, may be chronic or delayed. When this disease was first apparent, an industrial plant had been synthesizing acetaldehyde from acetylene. Mercury compounds catalyzed the process, which also produced small amounts of MM. Having no use, the MM was discharged into the sea', where various types of marine fauna, some of which are food sources, concentrated this noxious substance in their bodies. Other MM sources include the vinyl chloride, chlor-alkali, and paper industries. Japan was not the only country to suffer. In Iraq, for example, from 1971 to 1972, a disastrous Minamata-type epidemic led to 459 deaths out of 6500 cases. The disease was traced to two months of consumption of bread made from wheat which contained an ethyl mercury-based fungicide.
Other major offenders The conference defined heavy metals as iron and any metal heavier than iron. Of greatest concern are heavy metals which are toxic and easily available, such as mercury, lead, and cadmium-the unholy trinity-and copper, cobalt, nickel, tin, zinc, and certain others. Excess hexavalent chromium is also a matter of concern. Between 1940 and 1956, the Itailtai ("Ouch-Ouch") disease was endemic in the Zinzu River area of Japan. Most sufferers were middleaged and elderly women. Their illness stemmed from an intake of cadmium, thought to be derived from the Mitsui Mine on the Zinzu River. The cadmium was probably in the drinking water. In the Itai-ltai disease, the metal is believed to inhibit the uptake and retention of calcium in the bones. A s the disease progresses, the bones become extremely brittle and can frac-
ture in many places after very slight movements. The pain is considerable; the patient finally dies in excruciating agony. Other symptoms of cadmium poisoning include emphysema of the lungs, kidney dysfunction, and abnormal elimination of glucose and low-molecular-weight proteins in urine. Excess cadmium in the water affects the fauna adversely as well. For example, a material lowering of reproductive potential and resulting reduction in the population of brook trout occurred in waters laden with this metal. Waters with a higher cadmium, or other metal pollution load-at or above the incipient lethal level (ILL)-will kill the fish therein. Lead enters soils and waters to a very large extent near highways, also near lead mines and smelters. To assess lead distribution patterns, the University of Illinois studied an 86sq.-mi. area which was largely rural, yet strongly affected by the cities of Champaign and Urbana, Ill. Over the area, lead input from aut,omobiles alone was over 28,000 kg/yr. This lead settles in top layers of soils, mostly up to 10 meters from both sides of a highway. Such soils can contain more than 400 ppm lead, part of which finds its way to stream water or aquifers. Illinois University's Gary Rolfe predicted that lead might be found in the food chain, but the extent to which lead magnifies in the food chain from plants and lower animals up to man has yet to be ascertained. In vegetable crops, such as lettuce grown in the vicinity of Missouri lead smelters, lead content ranged from 8.9 to 1324.0 p g lead per gram of lettuce leaf. In humans, excessive lead seriously impairs the functioning of the CNS and peripheral nervous system. Production of blood is also affected, as is kidney performance. Young
people, especially children, are highly susceptible to lead poisoning. Fish can be adversely influenced by 0.03 mg/l. of lead in water. However, it appears to take 13.2 mg/l. in soft water, and 220 mg/l. in hard water to kill most species of fish.
Thegoodandbadguys Before the panic button is pushed, the public must realize that small amounts of metals are essential, not only to aquatic organisms but to humans as well, to survive and function. The role of iron as a principal component of blood must be cited as a prime example. Also, if a person does not ingest a certain minimum of cobalt-containing vitamin BIZ, he may sicken and die from pernicious anemia. Moreover, minute amounts of manganese, chromium, zinc, and copper may be vital to man as well as to numerous aquatic species. As a case in point, a snail population having a lack of copper in its environment, is unable to produce its respiratory pigment, hemocyanin. Detrimental effects might also be found in fish which cannot obtain the trace metals they need. For this reason, among others, one might question sincere, though perhaps misguided demands for water quality regulations requiring total removal of metals from water supplies. On the other hand, an excess of the “good guys” in the water brings out the bad in them. For instance, when copper and zinc concentrations are high, though below the ILL, they act as a barrier to salmon trying to migrate upstream to spawn. These salmon apparently do not seek an alternative spawning site, but go back to sea without spawning. In Nova Scotia, for example, in a river which carried effluent from mines of these metals, salmon spawning was re-
Some political fallout Research on heavy metals in the aquatic environment has had some political fallout. Tokyo University’s Ui told the ICHMAE that when the cause of Minamata disease was suspected, management and employees of Chisso Corp. apparently engaged in a conspiracy of silence concerning this matter. Moreover, possibly because of Chisso’s pressure, the Japanese government was quite uncooperative about providing data to researchers investigating the Minamata disease outbreaks of the 1950’s and 1960’s. The government reversed this policy only very recently, when Minamata disease was seen to have reached epidemic proportions, and could no longer cavalierly be flushed down the drain.
duced by 10-22%; what eggs were deposited were insufficient and showed poor hatching and survival rates. Other metals, such as chromium, nickel, cobalt, and ferrous iron, below the ILL, badly affected growth, reproduction, and stimulus response in a number of fish. Certain aquatic insects, however, exhibited greater heavy metal tolerance than did fish.
Regulation problems It would be very easy to decree zero heavy metal concentration in all waters. All it takes is a stroke of the pen. Enforcing this decree, however, would be virtually impossible. For example, some heavy metals come from purely natural sources, such as mercury ore veins. Very often, tracing these sources, much less neutralizing their contributions, would prove infeasible. Prescribing permissible levels of heavy metals in water is itself a monumental task. For each metal, and for various metal combinations (for there might be synergism), the concentrations above which adverse effects begin must be determined. Then, while many powerful, precise analytical techniques for ascertaining very minute amounts of metals in water exist, standard methods, which would make legislative sense and be admissible in a court proceeding, and which are not overly difficult to employ, would have to be decided upon. Moreover, when meaningful standards can be promulgated, they should inflict as little economic injury as possible. A good deal of thinking, talking, and experimentation has been done with all this in mind, but the proverbial bucket has received only its first drop. Research needs The harsh fact is that next to nothing is known about heavy metals in the aquatic environment, aside from what little has been learned from protracted mercury and cadmium poisoning epidemics. Some sketchy knowledge has been gained about heavy metal distribution long after introduction into water. To extend this knowledge, Finland’s Jorma Miettinen and his team will deliberately contaminate a 4-acre Finnish lake with mercury, perhaps before the end of the year. They will then monitor the spread of inorganic and organic mercury in and around the lake, and in its biota. However, there is much more to be learned. For example, do living creatures, including man, build up tolerances to toxic heavy metals slowly ingested for months and years? I f so, are there any subtle, hidden, or delayed-action effects
The food chain riddle Adaptability of lower forms of life to foreign materials is almost incredible. Aerobic and anaerobic living microbes have been found in waters with a pH of 0-13, temperatures of -18 to +104”C, salinities of 0 ppt to concentrated brine, and from 7 miles under the sea surface to the summit of Mt. Everest. They have been known to metabolize hydrogen sulfide, meteoric iron, kerosine, and other such “gourmet foods.” With that in mind, the public can readily imagine biota at the lower end of the food chain adapting to live with mercury, lead, polychlorinated biphenyls, and other waste products. At the recent ICHMAE Tokyo University’s Ui expressed deep concern that this process may have already begun and could have dark implications with respect to future availability of food to man. whose relationship to heavy metal intake might be proved only after exhaustive research, or not be conclusively proved at all? As a case in point, Holland’s A. J. de Groot told the ICHMAE of an old seal found near the mouth of the Rhine. I t was dead. I t s liver contained 700 ppm mercury; it should have died long before that level was attained. Frank D’ltri, of Michigan State University, spoke of increased violent crime among Ojibway Indians near Dryden, Ont., after a paper mill not far away, which contributes mercury to waters in the vicinity, went into full operation. Also mentioned were people with no visible symptoms, but whose nervous tissue, at autopsy, had lesions typical of mercury poisoning. Also to be studied are lengths of time needed to purge toxic heavy metals from the body, and whether all can indeed be removed. More needs to be learned about precise chemical and biological effects of these metals, and the etiology of these effects: at what levels signs and symptoms appear with one metal or combinations of metals: and any genetic effects. Finally, there is the nagging food chain question. Generally, lower forms of life seem more able to metabolize toxic heavy metals. As we go up the food chain, do heavy metal concentrations magnify? I t is a disturbing thought that for this reason, some of our food may become too toxic to consume (remember swordfish?), and that many sea and lake fish, mollusks, and crustacea, could no longer appear on mankind’s table in a world whose food scarcity grows by leaps and bounds every day. JJ Volume8, Number 2, February 1974
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This way to a better environment 1. ENVIRONMENTAL SYSTEMS ENGINEERING
2. METROPOLITAN TRANSPORTATION PLANNING
Linvil G. Rich, Clenison Lnh-ersity. 1973, 418 pages, 816.50. Instructor’s .b’anual
John W. Diclrej (Senior Author), Virginia Poljtechnic Institute and State Lniversity. 1974, 512 pages (tent.), S16.50 (tent.)
Co\ ering a broad spectrum of environmental topics, this quantitatiye introduction uses a $)stems approach in the analysis of en\-ironniental phenomena and in the selection and design of engineering facilities used for controlling the en\ ironnient.
The contributors to this volume offer an insight into an interdisciplinary approach to sol\ ing metropolitan transportation problems. Consisting of engineers and planners, an architect, urban designer and landscape architect, the authors pro\ ide a modular “problem solving” franienork into \\ hich further information on various aspects of metropolitan transportation planning can be integrated.
3. PRINCIPLES OF URBAN TRANSPORT SYSTEMS PLANNING B. G. Hutchinson, University of FF-aterloo, Ontario. 300 pages (tent.). S18.00 (tent.). Solutions 3fanual
1971,
4. SCIENTIFIC STREAM POLLUTION ANALYSIS
The processes involved in urban transport strategic planning are described in depth and \\-ithin a systems type framework in this test. The first part of the book describes techniques used to estimate travel demailds likely to he created by a gi\--en land use arrangement including trip generation anal)-sis, modal split analpis, trip distribution analpis and traffic assignment analgsis. A family of Lowry type land use models is presented. and other topics covered include transport technology, concepts of urban structure. economic evaluation, urban information sources and urban goods movements.
5. AIR POLLUTION H. C. Perlrins, Lni\ersitj of Arizona.
Nelson Leonard Uemerow, Slracuse Lnixersity. 380 pages (tent.). S16.50 (tent.)
1974,
4 caieful balance of the hjdrological, chemical and mathematical concepts in\ ol\ ed in the e\ aluation of stream qualit) is achie\ ed in this comprehensi\ e description of the anallsis of I\ ater pollution. Practice problems are included, and coinputatioii techniques for deoxxgenatiori and reaeration rates ale described and anal)zed, a- are all factors affecting 0x1 gen concentration to gi\ e an o\ erall 0x3 gen sag cur\ e in a stream.
6. ENVIRONMENTAL PROTECTION 1974, 480 pages
(tent.), S16.50 (tent.). Solutions llfunual
To date, this is the on11 truly engineering-oriented text on the subject that draws upon the student’s hachground in analyzing and sol\ ing problems in air pollution. The treatment is sufficieiitl) detailed to enable chemical, mechanical, and sariitar) engineering students to sol\ e a \ ariet) of problems. A complete discussion of the global effects of air pollution is included along M ith numerous applications-tj pe problems.
__-_-------------FOR 10-DAY FREE
Emil T. Chanlett, Lni\ersit) of Yorth Carolina a t Chapel IIi11. 1973, 569 pages, $15.50
Environmental Protection describes the rationale for the management and protection of our land, air, nater and energ) resources. The consequences of misiiianagement of the majoi en\ ironrnental components are examined a t three le\els: 1) effects on health, 2 ) effects on comfort. con\enience, eficiencj and esthetics, and 3 ) effects on the balance of ecosj steins and of r e n m able resources.
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114
Environmental Science & Technology
Think ecology when you drink The great American pastime is football with beer or soap operas with soft drinks. Either combination offers a diverse choice of beverages and containers. The public has gone through aluminum cans, steel cans, glass bottles, and the terrible-tasting plastic juice bottles. It has also struggled through the soul-searching test of the nonreturnables versus the recyclables. And where are we now? Later this year, Monsanto Commercial Products Co. plans to market its Lopac containers. Thoroughly researched and tested over a 10-year
consumed in ~a~ufaGture a
ac
Steel can
fitas
#urninurn can
Sourel: MonsantoCommercial Products Co.
_ _
--_
._
period, these containers, made from nitrile-based polymers, are aimed to fit consumer criteria-lightweight, safe, easy storage, economical, and taste protective. They also promise to satisfy environmental energy and disposal needs in air, water, and land.
For the consumer For a same size container, Lopac is one eighth the weight of glass, half that of steel, and approximately equivalent to that of aluminum. It will not explode in the freezer if Junior decides that would be a neat trick. I t tolerates heat (to 230” F) and cold. Extensive drop testing showed that this new bottle resists breaking from a height of 7 ft for a 10-oz size bottle, and a height of 4 ft for a 32-oz bottle. I n addition, fragmentation is slight upon breakage. The Lopac container also has enough flexibility to expand slightly under pressure buildup. I t is an “inert” material; this means that the polymer does not migrate into the drink nor will it absorb the taste component of the drink. That’s great for our taste buds, not to mention our health. Unlike glass, it is notch insensitive and will not weaken or fail upon marring or scratching.
refuse or garbage containing 4 % Lopac. In addition, the high fuel content of Lopac bottles allow incinerator operators to reduce the amount of fossil fuel needed for burning. Lopac, when left in municipal dumps or landfills was resistant to biodegradation and exposure to water and sunlight. Refill possibilities are still under investigation. Reprocessing of the polymer into new bottles is also feasible. After five repetitive cycles of sorting , grind i ng , wash ing , me1t i ng , and fabrication of new bottles from returned bottles, the polymer retained its initial rheological and chemical properties.
For the environmentalist
Energy requirements
Environmental impact studies (see box) were conducted at each stage of manufacture for four kinds of containers-Lopac, aluminum, steel, and glass. Air emissions of carbon monoxide, hydrocarbons, nitrogen dioxide, SUIfur dioxide, and particulate matter were comparable. Lopac had the lowest requirements for water use and discharged lesser amounts of effluents into the water. The solid wastes from Lopac manufacture were easily disposed of by incineration or landfill (for the tar portion), or recycled into new containers (for the scrap portion). Environmental effects of the onceused Lopac container were also assessed by Monsanto labs and teams from New York University and Midwest Research Institute. The emptied bottle would be ultimately disposed in the municipal solid waste systems, refilled, or recycled. Stack gases from municipal incinerators were no different for standard
Scarce availability of energy has made this issue vital. Lopac is made from the previously unutilized and discarded by-products of fossil fuelethylene and propylene. Comparing energy consumption (see box) for all four kinds of 10-oz. size container manufacture, Lopac had the lowest requirement. In addition, Lopac contains 800 BTU/lO-oz bottle energy, recoverable in a heat recovery-type solid waste system. Energy needs for first recycle is also lowest for Lopac; with each recycle, Lopac proportionately used less energy than the other three materials.
Put to the test Two bottling companies have approved the Monsanto container. I t will be interesting to see how fast the public responds to and accepts the new bottle which offers energy and materials conservation, recyclability, and solid waste disposal attributes, as well as safety improvements and consumer benefits. LCG Volume 8, Number 2, February 1974
115
ENGINEERS. ENVIRONMENTAL SCIENTISTS 1 . On which of these sites would you locate a power plant?
2. What are the cooling system alternatives?
3. What are the potential effects on biota? 4. What are the tectonic and foundation aspects of the site? 5 . Which site will have the least environmental impact?
Can you answerany of these siting questions3 At Gilbert Associates we know that it takes a team of highly skilled professionals-working together-to solve the problem of providing electric energy with minimal adverse environmental impact. If you are qualified, we have career opportunities for you as a member of our environmentalidesign team. Make a real contribution to the needs of industry and society-accept the challenge. We at Gilbert Associates are engaged i n environmental impact analysis, site evaluation and the design of nuclear and fossil fueled generating stations, with overall project planning and design responsibility. Are you looking for a company where creative minds t h r i v e . . . a n association with congenial co-workers.. . a salary and advancement potential consistent with your ability? We have the opportunity for you. We are located in Berks County, Pennsylvania in the heart of historical Pennsylvania Dutch Country, where you can find abundant recreational facilities, educational opportunities and suburban living, all within minutes of theoffice.
OPPORTUNITIES IN THESE AREAS: PROJECT ENGINEER Requires an M.S. preferably in Civil Eng.ineeringwith 2-5yearsexperience in analysis of environmental, economic and regulatory constraints for site selection. You'll develop studies and reports regarding civil aspects of site selection for nuclear and fossil power plants.
ENVl RON MENTAL ENGlN EER / ECOLOGIST
Requires an M.S. and 0-2 years of experience and education and/or related experience. You'll participate in site studies and environmental reports.
OSHA ENGINEER
NUCLEAR POWER PLANT LICENSING ENGINEER
Requires a B.S. in Engineering, a P.E. license or qualifications, and 510 years of experience, plus experience in preparation of USAEC, PSAR and FSAR construction and operating permits. You'll organize and supervise the preparation apd presentation of: SAR's, constru? tion and operating permits, environment impact reports, site qualification studies for nuclear power plants, and provide direction regarding regulations to design engineers.
Requires a B.S. in Engineering; 5-10 years experience; training and/ or experience in safety engineering, analysis, design evaluation, and plant inspection procedures; and thorough familiarity with OSHA requirements. You'll evaluate building and plant design for compliance with state and federal regulations, provide guidance to other engineers regarding safety a?d related design aspects,, maintain lialson with governmental agencies, and interpret (or obtain interpretation) of regulations.
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Become part of the answers. Send your resume in confidence to: Carl Mycoff.
ENGINEERS AND CONSULTANTS
P 0 Box 1498 EL , Reading, Pennsvlvania 10603 The Gilbert/CommonLuealth Companies Are Equal Opportunlb Emploqers M / F Clrrle No. 9
on Readers' Service Card
declares war on litter Keep America Beautiful, Inc., marked its 20th anniversary recently by launching a major antilittering campaign. The project aims at instilling new attitudes against such despoilment There is a campaign afoot to keep America beautiful, despite our sometimes less-than-beautiful impulses to dirty things up. i n fact, Keep America Beautiful, Inc. (KAB) has launched a full-scale study on why we litter. The group vows to fight the problem by first finding out the psychology behind our apparent lack of interest in keeping things clean, to change this psychology, and make responsible citizens out of us whether we like it or not. The New York-based KAB held a meeting there in December to launch the campaign. KAB president Roger W. Powers tells ES&T they have commissioned Scientific Resources Incorporated (SRI), of Morristown, N.J., to design a new research program to study simultaneously all factors involved in litter prevention. The project "will bring together, on a coordinated basis, community and scientific skills with the force of citizen awareness and action," he pointed out. Powers says that the chief factor to be studied will be the human behavioral aspects of littering. However, the project "will also seek answers in the physical and situational areas of collection and disposal, street sweeping, and law enforcement practices relating to littering." What all this means, Power says, is that KAB intends to find out first why people litter, then attempt to change their norms, or attitudes, toward littering. "Our effort will be to establish a norm whereby it is socially unacceptable to litter," he says. This will involve a total or "systems approach" whereby the KAB will consider the extent of the litter problem in a particular community. They then will undertake an area-wide analysis of the community's solid waste situation to find out how this may contribute to litter. The final step will be to work out solutions that best fit the particular community. Major questions Powers points out that many things can contribute to present litter problems. Major questions include: 0 The efficiency of collecting trash. DO collectors throw as much on the ground as they haul away? 0 Street sweeping by both city workers and business establishments. I s the waste picked up or
merely swept into th,e streets and gutters to blow elsewhere? 0 The placing and number of receptacles. Are they located where trash is likely to accumulate, and are there enough of them? 0 Coverings for trucks carrying trash and other debris. Are vehicles properly covered, or is trash allowed l o blow off into the streets? 0 The size and design of trash receptacles. Are they big enough, can they be easily overturned by dogs, and can they be conveniently picked up and emptied by collectors? Other problems, both physical and psychological, will not be as easy to deal with, Powers admits. For one thing, there are more items being manufactured today that have to be thrown away. This means industry will quite properly figure in making these decisions; however, this also inserts another variable, or potential stumbling block, to effecting change. Another thing, people travel more today, and tend to have a double standard about littering on the road while they wouldn't do so at home. The norm tends to weaken the farther one travels from home, Powers says. He adds that while KAB's project initially will focus on urban environments, their full effort will be to develop good norms that will carry over to the highways and countryside. KAB's plans. in the immediate future, are to try out its project in two pilot cities in the South-Charlotte. N.C., and Tampa, Fla. Powers says the South was selected because of the less likely possibility of weather problems such as snow, which could affect the purity of the results. He
KAB head Roger W. Powers Seeks coordinated solution
added, however, they plan "to come North with their results and apply what they find in a more general way." Prototype testing of theories in three communities in New Jersey was positive, Powers said. Projects outlined Stanley Silverzweig, executive vice president of Scientific Resources Incorporated, who is directing the study, outlined in broad terms how the projects will be carried out in individual communities. He said, first, there will be an effort to get a commitment from local leadership-sanitation officials, politicians, and interested citizens. KAB will do the initial contact work, and set up 6-8-hr workshops during which the community can work out its own cleanup plan, he said. The second step will be to run an institute for local industry and sanitation equipment manufacturers to inform them of the problems involved and to facilitate their involvement. A third step will be to gain media support, both national and local, to publicize the projects. As a follow-up, Silversweig said, the American Public Works Association, Chicago, and local university groups will make checks and compare before-andafter data to test the effectiveness of the projects. Beauty has many faces, according to KAB's thinking, and a cleaner America can lead to better things in other areas. Powers says KAB's approach can be extended to other areas of citizenship-those dealing with crime, drug usage, and other personally and socially destructive types of behavior. "The KAB campaign is designed to develop and instill a new norm of pride whereby we will first be proud of ourselves and then proud of being Americans," he says. KAB has been around for 20 years. It's a national, nonprofit, public service organization for environmental improvement. Officially, it is guided by a National Advisory Council composed of some 80 civic, service, and professional groups, as well as agencies of the Federal Government and industry officials. Its year-round environmental programs are carried out by more than 7000 citizen affiliates at both state and communitv levels. WSF Volume 8, Number 2, February 1974
117
