Pollution Prevention

Waste Containment In Domal Salt

Confining Zone

The most widespread concern about hazardous waste containment is the perceived threat of contamination of groundwater. This concern is warranted by the record of groundwater contamination associated with traditional near-surface disposal technologies. Therefore, the key question is whether a salt dome has a particular set of attributes that will prevent the release of contaminants to the environment in both short-term and very long term time frames. From a regulatory perspective, a no migration...

Lime Types Uses Composition And Treatment

Lime Schematic Diagram

Acidic industrial wastewater can be neutralized with slaked lime Ca(OH)2 , caustic soda (NaOH), or soda ash (Na2C03). Since slaked lime is less expensive than other bases, it is the most commonly used chemical for acidic neutralization 5 . Two types of commercial lime with their associated hydrates are high calcium quicklime, otherwise known as calcium oxide (CaO), and dolomitic quicklime (CaO and MgO). The composition of these will depend on the source of the parent limestone and the method of...

Contributors

Prevention Pollution Policy

Aly Utah State University, Logan, Utah E. J. Anthony CANMET, Ottawa, Canada Milovan S. Beljin University of Cincinnati, Cincinnati, Ohio Douglas M. Brown The Logistics Management Institute, Bethesda, Maryland M. S. Chandrasekharaiah Houston Advanced Research Center, The Woodlands, Texas Allen P. Davis University of Maryland, College Park, Maryland Steven K. Dentel University of Delaware, Newark, Delaware Merrit P. Drucker Army Management Staff College, Fort Belvoir, Virginia Jeffrey C....

Barrier Walls

Sketch Bentonite Slurry

The control of contaminant migration from existing disposal sites or impoundments may necessitate a vertical subsurface barrier to horizontal groundwater flow. Barriers commonly constructed include soil-bentonite slurry trench cutoff walls and cement-bentonite slurry trench cutoff walls. Vibrating beam cutoff walls, grout curtains, sheet piling, and composite walls are also used. For vertical barrier walls to be effective, they are generally keyed into an impermeable stratum of natural...

Siallon Treatment

Siallon Corporation provided a fully permitted pug mill capable of processing 20 tons of soil per hour, two experienced operator technicians, and the labor and equipment required to load the contaminated soil into the pug mill and stockpile the clean material on-site. Siallon Corporation also regularly sampled the treated material and had a certified laboratory perform EPA 8015 and 8020 analyses on all appropriate samples. The pug mill used for the encapsulation of the gasoline-contaminated...

Site Field Investigation

As a result of the uncertainties associated with the modeling results (in particular the leaching portion of the site conceptual model), a Supplemental Field Investigation was implemented. This investigation focused on better defining the source areas with respect to soil contamination and determining site-specific leaching potential to compare to OLM results. The following sections present an overview of the field investigation. 1. Development of Area-Specific Soil Boring Locations The first...

Pollution Prevention Programs

Prevention Pollution Policy

Pollution prevention is often discussed within the context of a widely accepted notion of a waste management hierarchy. The waste management hierarchy places the highest priority on reducing waste at the source of generation through the use of less toxic raw materials, equipment changes, process redesign, and better housekeeping and materials management. The second preference in the hierarchy is reuse and recycling of wastes that cannot be reduced at the source. The third preference in the...

Organizing A Waste Reduction Program

Because a waste reduction program affects many groups within a company, a program task force should be assembled. This group must include members of any department that has a significant interest in the outcome of a waste reduction program. The formality or informality of a waste reduction program will depend on the nature of the company. A program in a large, highly structured company will probably be quite formal, one in a small company, less formal. Table 2 lists the typical responsibilities...

Planning a Strategy

The steps involved in planning and organizing a waste reduction program are summarized in Table 4. Most small businesses do not realize how much waste they produce. Ask most managers if they use all of their raw material, or input, and they will probably say that they do. What they actually mean is that they process all of the raw material needed, not that they use the entire amount purchased. If they feel they are getting their money's worth, most managers will not give a second thought to...

Hunter Industrial North Dayton Salt Dome

Bedded Salt Versus Salt Dome Formations

The Resource Conservation and Recovery Act of 1976 (RCRA) and the more recent Hazardous and Solid Waste Amendments of 1984 (HSWA) have mandated the development of innovative technologies for the destruction, treatment, and or secure containment of hazardous waste as an alternative to land disposal methods currently in use. The Hunter Industrial Facilities, Inc. (HIFI) North Dayton Containment Facility is designed to use innovative technology that will meet the objectives and demands of the...

Introduction

Melt crystallization is a standard chemical industries purification process for chemical products such as naphthalene, para-xylene, dichlorobenzene, acrylic acid, monochloroacetic acid, bisphenol A, and others 1 . It is seen as an extremely selective separation process that can reduce contaminant levels to the ppm range. This provides an effective means to purify some products. Freeze concentration (FC) is usually associated with the process when the crystallizing component is water. In this...

Areas Of Application

Immobilization or separation of contaminants contained in polluted waters is an objective of increasing importance in a variety of environmental settings. Recent research has suggested in clear terms that chemically modified clay minerals represent a new and promising class of adsorbent materials for accomplishing this. Specific areas of application exist in potable water treatment 7,8 , industrial wastewater treatment 9,10 , and treatment or confinement of contaminated groundwater 11-13 ,...

Sludge Treatment

Sludge is treated prior to ultimate disposal for two reasons volume reduction and stabilization of organics. A reduced sludge volume minimizes pumping and storage requirements and lowers sludge handling costs. Stabilized sludge has a less offensive odor, and health hazard and nuisance conditions are minimized. Common methods to accomplish the two objectives include thickening, biological digestion, dewatering, and incineration. When incineration is used, there is no need to stabilize the...

Recycling

Recycling via use and or reuse involves either returning a waste material to the originating process as a substitute for an input material or using it in another process as an input material. Return to original process Raw material substitution for another process Example Reuse Return to Original Process. A printer of newspaper advertising purchased an ink recycling unit to produce black newspaper ink from its various waste inks. The unit blends different colors of waste ink together with fresh...

Prioritizing Waste Streams andor Operations to Assess

Ideally, all waste streams and plant operations should be assessed. Prioritizing waste streams and or operations to assess is necessary when available funds, personnel, or time is limited. Waste reduction assessments should concentrate on the most important waste problems first and then move to lower priority problems as time, personnel, and budget permit. Setting priorities for waste streams or facility areas requires a great deal of care and attention, since this step focuses the direction of...

Microheterogeneous Media

Photochemistry in homogeneous solutions is a subject familiar to most chemists. Microheterogeneous photochemistry is less so. The system here is somewhat homogeneous on a macro scale, but it is heterogeneous on a microscopic level. Many of the processes in these systems are taking place at the interface of two phases. The colloidal semiconductor sols and surfactant micellar systems are good examples of microheterogeneous media. Thus, all the microheterogeneous systems are at least two-phase...

Tertiary or Advanced Treatment

Secondary treatment followed by disinfection can kill nearly all pathogens and remove 85-90 of the BOD and TSS in raw wastewater. However, only very little of some pollutants, such as nitrogen, phosphorus, and heavy metals, can be removed by biological treatment. Nitrogen and phosphorus are important plant nutrients. If they are discharged into a lake, algal blooms and eutrophication (accelerated aging) may occur. Also, nitrogen in the secondary wastewater effluent may be present mostly as...

Metal Sulfide Precipitation

Precipitaci Metal

The solubility products of metal sulfides are several orders of magnitude lower than those of the corresponding hydroxides. This should make it feasible to precipitate the heavy metals from solutions containing complexing agents that prevent metal removal by hydroxide precipitation. Also, the pH range for the precipitation of metals as sulfides is much broader. Table 3 lists the solubility products for metal sulfides of the type MeS, Me2S, and Me2S3 15 . Metal sulfide precipitation occurs if...

Treatment

Treatment technologies reduce the toxicity, mobility, or volume of affected media or wastes, thus reducing the potential for constituent exposure to human health and the environment. Removal and disposal technologies may be required in conjunction with treatment alternatives, although some treatment technologies can be implemented in situ. Solid Waste, Soil, and or Sediment Treatment Air Stripping Description. Air stripping of volatile organic compounds (VOCs) in soils can be accomplished by a...

Fluidized Bed Combustion Primer

Fluidized Bed Bubble

A fluidized bed consist of a bed of particles suspended above a grid (e.g., perforated plate) by a fluid (air) moving upward through holes in the grid. The velocity of the fluid must be sufficient to suspend the particles so that they move freely in the bed region. If the velocity is too low, the particles are immobile in a fixed bed at velocities greater than the particle's terminal velocity, the particles are blown completely out of the bed, i.e., elutriated. In the fluidized bed regime,...

Flow Diagrams and Material Balances

Different materials and procedures are used to execute each process however, every operation offers an opportunity to track material flow. Figure 1 provides an extremely oversimplified material flow chart. Before a waste reduction plan can be formulated, it is crucial to determine the amount of waste that the business is already producing. How Perform a waste audit. What is a waste audit It is the direct application of the law of conservation of matter taught in Physics or Chemistry 101 Matter...

Cavern Closure

Shoreline Preventing Erosion Diagram

Salt cavern repositories are ideal for safe isolation of solidified hazardous waste. The subsurface disposal facilities can be designed and constructed in such a way that there is virtually no possibility of escape of the contaminants within the time frame to perpetuity (defined as 10,000 years by EPA). Solution-mined caverns in dry domal salt meet the requisite criteria for this demonstration and provide the only plausible solution to this problem, for the foreseeable future. Fortunately, dry...

Secondary Treatment Biological

Trickling Filter Column

Physical treatment of raw municipal wastewater by sedimentation removes most of those pollutants that will either float or settle out by gravity, which accounts for only approximately 35 of the BOD. The major purpose of secondary treatment is to remove nonsettleable (colloidal and dissolved) solids in the wastewater. Secondary treatment is generally considered to mean at least 85 efficiency in reducing BOD and now represents the minimum degree of treatment required by law in most cases. Some of...

Primary Treatment

Inlet Outlet Zone Flocculation

Wastewater contains suspended matter that has a higher specific gravity than the liquid and is in a relatively quiescent state, the particles will settle out because of gravity. Grit chambers remove grit, including gravel, sand, and heavy particulate matter such as corn kernels, bone chips, coffee grounds, and broken glass. All of this accounts for only a portion of the inert suspended solids in raw sewage. After grit removal, the wastewater still contains suspended solids, which are then...

Preliminary Treatability Studies

Initially, studies were done on the battery casings and soils to determine if physical methods could be used to concentrate the contaminants and reduce the volume of material that had to be treated. Since lead compounds have a relatively high density, gravity separation was a logical choice. The fineness of the soils (< 37 (im) suggested that a Bartles-Mosely vanner be used for the gravity separation since it is the only gravity separator that has had any success on < 37 fxm materials. The...

Cleaning Procedure Tests And Results A Battery Casing Wastes

Elutriation Device

The bench-scale cleaning process developed (see Figure 1) consisted of prewashing, gravity separation, granulation and sizing, carbonation, and acid leaching. Prewashing the battery casings removed most of the adherent sludge and fine metallic lead. This prevented the sludge and metallic lead from becoming embedded in the casings during subsequent size reduction. The as-received battery wastes were mixed with water, tumbled in a ball mill without a grinding medium for 1 hr, and then screened...

Soil Wastes

Tests on the soil samples were conducted simultaneously with the research on the battery casings. Since upgrading by gravity separation, flotation, etc. were not effective, the hydromet-allurgical approach used for the casings was followed for the soils (see Figure 3). First, the as-received soil samples were characterized and chemical analyses were performed. The amount of lead in the soils varied widely, depending on the specific site and the area within that site. Partial analyses on one...

Institutional Actions

Institutional action technologies reduce potential exposures to site constituents by indirect methods rather than by containment or treatment of the affected media. Institutional actions include physical barriers and deed restrictions. Description. Physical barriers provide an easily implemented, low-cost method for restricting pedestrian and animal traffic across areas of concern, thus decreasing the potential for exposure to site media or damage to on-site storage or containment structures....

No Action Technologies

No action implies that no remedial actions are to be conducted on the media of concern. Actions such as groundwater monitoring and site inspections are included as no action technologies because they are intended to detect changes in site conditions rather than to actually remediate existing contamination. Description. Long-term, periodic groundwater and or surface water monitoring to detect changes in site conditions, such as the migration of constituents in groundwater, due to natural...

Industrial Waste

A significant amount of the waste discarded by industry is reused. The wastes that are reused save the environmental degradation caused by input material acquisition, reduce energy use and its associated impacts, and reduce the impacts of end-of-the-pipe control and final disposition. For example, when paper is produced by chemical pulping, lignin is dissolved to free cellulose and hemicellulose fibers. In addition, the pulping chemicals and lignin combine to produce black liquor. Originally,...

Treat the Task Seriously

Success in the elimination of pollution depends on the effective efforts of all employees. If environmental issues are viewed as solely the responsibility of an environmental department or if input to production process modifications are provided solely by process engineers, the needed commitment from other departments may not be achieved. Further, if the firm fails to maximize its use of available information, it may miss important insights. To a large extent, the degree to which individuals...

State Pollution Prevention Contacts

Alabama Hazardous Waste Division HAMMARR 241 Mineral Ind. Bldg University of Alabama P.O. Drawer G Tuscaloosa, AL 34587-9644 (205) 348-4878 Pollution Prevention Program Department of Environmental Conservation Toxic Substances Control Program Department of Health Services Alternative Technology Division Juneau, AK 99811-1800 (907) 465-2671 P.O. Box 942732 Sacramento, CA 94234-7320 (916) 322-2822 Alaska Health Project 431 W. 7th, Suite 101 Anchorage, AK 99501 (907) 276-2864 Waste Minimization...

Structure And Biodegradability A Structure Relationships

There is no clear and consistent way by which to predict biod gradation of a specific compound in soil absent specific site-related experiments. There are rules of thumb, however, that can be applied when assessing the potential for a compound to be significantly degraded. These general theories are rooted in chemical class or type, solubility, and chemical structure. The following rules of thumb can generally be applied within classes of chemicals Water-soluble compounds are usually degraded...

Anaerobic Biological Treatment

Anaerobic processes have been employed recently for treating dairy wastewaters. A full-scale anaerobic treatment plant for treating dairy wastewater was first installed in Canada at Granby, Quebec. This plant, which treats the cheese waste and several other processing wastes, consists of two units a downflow fixed film reactor and an upflow sludge blanket reactor 17-20 . The second Canadian anaerobic digestion system, at Millbank Cheese and Butter Ltd., is treating cheese whey only 20 ....

Chromate Reduction

Disadvantage Cyanide

Hexavalent chromium is toxic, and most chromates are water-soluble. Only Ba2 +, Pb2 +, Hg+, and Ag+ form insoluble chromates. Pollution with chromates is especially troublesome, since chromates are not adsorbed by soil and thus reach the groundwater table rapidly. Most chemical control strategies are based on the reduction of hexavalent chromium (Crvl) to trivalent chromium (Cr111). Trivalent chromium is much less toxic than chromates and forms a hydroxide with a solubility minimum in the pH...

Applications

The observation that a number of solute species present in the solution were photocatalyzed at the illuminated semiconductor surface evolved from the photodecomposition studies of water with solar radiation. Bard and coworkers 26-30 have shown that many hazardous species, including some of the EPA priority pollutants, could be degraded into innocuous species at the illuminated titania semiconductor surface. Their work formed the nucleus for the concept of photocatalytic degradation of hazardous...

References

L., The treatment of dairy wastes, Dairy Ind. Int., 45(11), 23-28 (1980). 2. New Zealand Dairy Board, Annual Report for Year Ended 31 May 1982, New Zealand Dairy Board, Wellington, New Zealand, 1982. 3. Environment Canada, Evaluation of Physical-Chemical Technologies for Water Reuse, Byproduct Recovery and Wastewater Treatment in the Food Processing Industry, Rep. No. EPS 3-WP-79-3, Ottawa, Canada, 1979. 4. Harper, W. J., and Blaisdell, J. L., State of the art dairy plant wastes...

Environmental Impact of Adding PCSs to HMA

Leachability Test for HMA with PCS The increase in the number of organic contaminants being detected in groundwater as well as in surface water is causing concern because of potential health risks claimed to be associ ated with human exposure to these substances. Soil contaminated with petroleum product is a potential threat to both surface water and groundwater thus a key issue is whether hydrocarbon will leach out from the asphalt mixture when it is mixed with PCSs and used to pave roads. The...

Manufacturing Methods

Several well-known processes by which caustic soda is produced are those employing a diaphragm cell, bipolar diaphragm electrolyzers, mercury cell, or membrane cell. In the diaphragm cell process, water is added to sodium chloride with direct current to produce chlorine, hydrogen, and sodium hydroxide. The overall reaction is 2 NaCl + 2 H20 + direct current - Cl2 + H2 + 2 NaOH An asbestos diaphragm is used to separate the anode and cathode this serves to keep the caustic soda and hydrogen...

Metal Hydroxide Precipitation

After the oxidation of cyanide and reduction of chromate, the metals can be precipitated as hydroxides. A prerequisite is the absence of strong complexing agents such as ethylenediamine tetraacetic acid (EDTA). The degree of metal precipitation is dependent on pH. At a given pH, different metals exhibit different solubilities. The amount of metal in solution as a function of pH can be calculated theoretically from the solubility product (Ksp) of the hydroxide. For divalent metals this takes the...

Case Study II

This study involves the remediation of 40,000 tons of heavy metals-contaminated soil at the Thompson-Isaacson site in Tukwila, Washington. In this soil, arsenic was the principal metal of concern. The other metals that were evaluated were barium, chromium, copper, nickel, lead, and zinc. The need for the remediation arose as a result of the planned development of the site, which entailed the construction of an industrial structure necessitating substantial excavations for foundations and...

Cyanide Oxidation

Cyanide (CN )-based plating baths exhibit the unique property of producing fine crystalline, shiny metal coatings. They are therefore widely in use despite the high toxicity of cyanide and the greater control effort necessary in pretreatment. Cyanide destruction is commonly achieved through oxidation in the alkaline region using chlorine gas or sodium hypochlorite. Peroxide oxidation and treatment with ozone are reported to be feasible. Electrolytic oxidation has advantages in treating highly...

ORP and pH Measurement

To apply the chemistry discussed in Section II to an automated process, it is critical to control the pH and the oxidation reduction potential (ORP). The adjustment of the pH and the ORP is achieved with electrodes in combination with millivolt controllers and chemical feed pumps. The electrode system for pH determination consists of a glass electrode and a reference electrode. The most common reference electrode is the saturated calomel electrode Hg Hg2Cl2 KCl(sat) with a constant potential of...

Chu and Chens Relative Potency Factor Approach

Originally, risks attributed to exposure to cPAHs were derived by assuming that all cPAHs are equipotent to benzo pyrene. Realizing that there is much scientific evidence that demonstrates that benzo a pyrene is regarded as one of the most potent cPAHs and that all cPAHs are not equipotent 2 , alternative methods have been developed that assess risks more fairly. A study conducted by Margaret Chu and Chao Chen of EPA's Carcinogenic Assessment Group provides evidence to support these contentions...

Remedy Selection Criteria

The National Contingency Plan (NCP), as revised in March 1990, sets forth the selection criteria to be used in the evaluation of remediation alternatives. Remedies are evaluated in three steps in accordance with the NCP and USEPA guidance documents 1. Identification and evaluation of remedial technologies usually targeted at one or more specific site problems 2. Combining of suitable technologies into remedial alternatives usually intended to address the entire site 3. Detailed analysis of...

Aerobic Biological Treatment

Tabulated information on a wide range of activated sludge plants, both laboratory and industrial units, treating dairy wastewater is available elsewhere 8 . The treatment efficiency values vary from about 25 to over 99 with an average removal efficiency of about 85 . With good operation, BOD removal efficiencies in excess of 90 are easily attainable with activated sludge systems however, even an efficient system may not be able to reduce the BOD from 2000 mg L in the dairy waste to 20-30 mg L...

Bottom Seals Liners

Barriers And Liners

In new waste containment facilities, it is usually necessary to provide a liner system beneath the waste disposal area. The major function of a liner is to prevent leachate or waste from migrating downward and entering the groundwater flow regime. The barrier layer for liner systems can consist of native clays, processed clays, or geosynthetic membranes as previously discussed for covers. It is important to note that under the present U.S. regulations, the use of a synthetic membrane liner is...

Description of Multimed

Multimed is a recently developed user-friendly computer model that is capable of simulating the release of chemicals in leachate form from a source (or designated area) at the site to soils directly beneath the source. In addition, Multimed can be used to further simulate chemical fate and transport in the unsaturated and saturated zones, followed by possible interception of the subsurface plume by a specified receptor (e.g., a well or surface stream). The fate and transport of a chemical...

Cavernleaching Techniques

Cavern Leaching

The fundamental technique of cavern development involves drilling and cementing concentric casings into the salt dome, then drilling an uncased hole to expose the salt for dissolution. Two concentric leaching strings of pipe provide circulation of water through the well to dissolve the salt (Figure 7). Water is injected through either the inner leach string or the annulus, depending upon the leach phase. As water is injected and cavern development proceeds, a flow of brine is circulated back to...

Vegetative Root Attack on Liners

Landfill sites are generally planted with vegetation to enhance vapotranspiration and for the purpose of beautification of unattractive landfill sites. Further, without regular maintenance, woody vegetation will begin to appear. Trees and vegetation also have a detrimental side effect. Two important phenomena related to how tree roots attack liners are discussed below. 1. Tree roots looking for nutrition (food) and water will grow deeper into the subsurface of the landfill area. Roots can and...

Barriers To Waste Reduction

Although economic factors often work in favor of pollution prevention approaches, there is always some resistance to change of any kind. Waste reduction projects can reduce operating costs and improve environmental compliance, but they frequently bring out conflicts between different groups within a company. Economic barriers to pollution prevention include the following Inaccurate market signals. Sometimes the immediate cost of releasing toxic substances is less than the cost of implementing a...

Top Seals Cap or Cover Barrier Layers

Infiltration Basin Schematic

Top seals (i.e., surface seals, caps, covers), as shown in Figure 10, function to control surface water so as to minimize infiltration, maximize runoff, prevent direct contact (such as by burrowing animals, which may dig into the landfill areas), and thereby reduce leachate production Figure 9 Schematic drawing of a vibrating-beam slurry wall. (1) Top seal (2) landfill material (3) bottom seal. Figure 9 Schematic drawing of a vibrating-beam slurry wall. (1) Top seal (2) landfill material (3)...

Delivery Of The Technology

For site remediation applications, the technology is delivered by means of a mobile system that can be operated under a TTU (Transportable Treatment Unit) permit. The equipment is versatile and self-contained, requires a relatively small space, and can be made operational on a site within two to three working days. The principal elements of the treatment system, shown schematically in Figure 1, consist of the feeder, magnet, screen, pug mill mixing plant, and polysilicate blending unit. The...

Gaseous Emissions A Nitrogen Based Species

As indicated earlier, fluidized bed combustors operate at temperatures of 800-950 C, several hundred degrees below temperatures for suspension or pulverized fuel fired boilers. At these lower temperatures, nitrogen in the air is not fixed, and therefore the majority of NO (emitted primarily as NO rather than N02) originates from fuel-bound nitrogen. Conversion of fuel nitrogen to NOj. is typically in the 10-25 range. The bulk of the fuel nitrogen is either directly converted to N2 or reduced to...

Practical Limitations

Given the complexity of the bioremediation process, it is often as critical to know the limitations of the site-specific scenario as it is to know how to apply the technology. Bioremediation is not unlike a golf swing to play well, good mechanics are everything. Yet, recognizing flaws and adjusting them seems to be an insurmountable task. Environmental factors may stunt or preclude biod gradation even in the presence of engineered organisms. Biod gradation at residual concentrations of the...

Firing of Waste Biomass

CANMET has tested a number of waste biomass fuels in pilot-scale bubbling fluidized bed combustors (40 cm X 4 cm units with a total height of 5 m) 35 . The fuels that have been burned are paper waste pellets, alfa grass, wood chips, corncobs, and rice husks. Proximate analyses of the fuels, where available, operating conditions, combustion performance, and emission levels are given in Table 1. The only serious problem associated with burning these fuels was feeding them into the bed. This was...

Siallon Applications And Mixing Equipment

The Siallon microencapsulation process is applicable to the treatment of a wide variety of waste materials. The hydrocarbons that have been successfully treated and found to be amenable to treatment by microencapsulation include crude oil, gasoline, coal tars, creosote, lubricants, diesel fuel, jet fuel, PCBs, and refinery wastes. The differences between many types of wastes are related not so much to the type of contaminant as to the physical form of the waste matrix. The treatments of pure...

Energy And Technology

A large variety of thermal, physical, chemical, and biological technologies are available to use wastes productively. The appropriate technology depends on the state of the waste (solid, liquid, or gas), the type of waste (organic or inorganic), and the end product (material or fuel). Organic wastes can be used economically as fuels or as raw materials that is, they can produce or conserve energy. Inorganic wastes can only be used as raw materials. In general, the thermal technologies produce...

Contaminated Water and Pressures Produced in the Landfill Site

Leachate produced in a landfill site generally results from the interaction of infiltrating liquids with the landfilled material and from the liquids contained within the landfill material at the time of disposal. The properties of leachate change from community to community as well as from season to season. The parameters and their range of concentrations are shown on Table 2. Figure 2 Schematic diagram illustrating cumulative settlement of waste due to decomposition of organic matter versus...

Discussion

In its most basic form, FC has been employed since as far back as the Middle Ages. Beer or wine in wooden barrels would be exposed to the cold winter nights, causing water to freeze along the barrel walls and leaving a concentrated product in the middle of the ice shell. In more recent times, a few companies have tried to commercialize FC processes. The main problem with most of these attempts was the difficulty in separating the ice from the concentrate. Filter presses, centrifuges, and...

Toxic Chemicals and Metals

A wide variety of toxic organic and inorganic substances are found in water in very small or trace amounts. Some of these substances are from natural sources, but many come from industrial and agricultural activities. Many of these contaminants can be dangerous to public health. Some heavy metals that are toxic are cadmium, chromium, lead, silver, and mercury. Arsenic, barium, and selenium are also poisonous inorganic elements. All these chemicals and metals must be monitored in drinking water.

Photolytic Degradation

Photolytic degradation uses sunlight or artificial sources of ultraviolet (UV) light to initiate photochemical reactions in hazardous waste 16 . These reactions occur faster when the process uses shorter wavelengths or more energetic light. One concern when using high-energy light is the possibility of eye exposure and subsequent injury. Sunlight contains a variety of wavelengths of light, some of which may cause biological damage if viewed for extended periods or if concentrated. Focused...

Photocatalytic Studies in Micellar Microemulsion Media

Though extensive investigations of micellar and microemulsion systems have been reported, photochemical degradation studies of toxic pollutants are limited. The presence of the micellar or microemulsion medium alters the photochemical reactions of a species from its behavior in a homogeneous medium. A comprehensive account of the photochemical processes in micellar and microemulsion media is given in the book edited by Kalyanasundarum 48 . Though micellar media offer several unique advantages...

Air Stripping

Air stripping of groundwater may expose workers to hydrocarbons when work is carried out in the vicinity of the effluent. There are several potential exposure points, including sampling points, leakage from lines, monitoring wells, the insides of vessels during maintenance, and effluent vents. The design of sparging wells should include assurances that the extraction well pressure will always be less than that of the injected air well. If the extraction line includes a dilution port, a check...

Fbc For Waste Minimization

Due to low organic emissions levels, FBC is a promising technology for disposal of organic material-laden wastes. Donlee Technologies (USA) has developed a CFBC boiler to incinerate infectious hospital wastes by cofiring with coal 16 . Based on pilot-scale testing, they report that PAH, dioxin, and furan emissions were typically well below those achieved with other types of hospital waste incinerators. Furthermore, suppression of HC1 of up to 50 was achieved. Organic emissions met both the...

Regulatory Framework

The regulatory framework of the federal environmental laws (and such states as California) do not deem everything as hazardous and mandate its disposal in a Class I landfill or by incineration. A review of current regulations proves quite the contrary. The letter, spirit, and intent of current hazardous materials legislation is to promote and develop alternative technology that encourages the use, reuse, and recycling of materials rather than the archaic load, haul, and dump remediation...

Where To Get Information On Toxic Chemicals Pollution Prevention And Green Design

In designing any project, engineers need to know which chemicals to be concerned about. Thousands of chemicals are in use in the marketplace today. Hundreds of those chemicals are regulated by the federal and state governments. Although engineers need not be expert on the environmental impacts of materials used in engineering projects, they should be aware of the chemical make-up and properties of materials in use and whether or not the chemicals used are regulated or of some environmental...

Summary of Key Federal Environmental Statutes Enacted Since 19701

In 1970, Congress established the U.S. Environmental Protection Agency (EPA) with the enactment of the Reorganization Act of 1970. This act consolidated the various environmental management responsibilities that were previously dispersed throughout the executive branch agencies, for example, Department of Interior (federal land management, mining), the Department of Agriculture (pesticide registration), and the Federal Water Pollution Control Administration (development of scientific and...

The Resource

Exclude large groups of wastes (such as agricultural and nonhazardous wastes). They also lack consistency, as substances are often added to or subtracted from these lists. Still, these definitions are commonly used by the trade associations and government agencies that collect data. Their surveys usually concentrate on waste materials that are deemed hazardous or are suspected of being so. A second obstacle is that the collection of waste data is not centralized or comprehensive. To calculate...

Municipal Waste

Municipal solid waste can be converted to energy by thermal or biochemical technologies. The commercial thermal technology is combustion to produce steam for industry, hot water for district heat, or electricity for the grid. MSW may be burned as received in specially designed facilities on a hearth (typically 25-50 metric tons day per unit) or on inclined grates (typically 250-1000 metric tons day per unit). In addition, solid fuel can be produced mechanically. This refuse-derived fuel (RDF)...

For Contaminated Sites

Funk, Ronald G. Fender, and Marilyn Hewitt Environmental Resources Management Group Exton, Pennsylvania I. CHARACTERISTICS OF ENVIRONMENTAL CONTAMINANTS There are literally thousands of substances that can contaminate the environment. In some cases, this contamination is related to natural conditions and is thus a background condition. Most often, however, environmental contaminants are related to human activity. Current regulatory programs governing contaminated sites...

Conclusions

Pollution Prevention Project Conclusion

To determine soil cleanup goals for the cPAHs protective of underlying groundwater, a conceptual model of potential constituent migration was developed. The site conceptual model consists of two elements (1) leaching of constituents from the potentially affected soils and (2) migration and dispersion of the constituents with respect to groundwater flow direction. The OLM was used to describe the leaching potential of the cPAHs present in the soil (Element I), while the VHS model was selected to...

Multiple Approaches to Environmental Decisions

The Logistics Management Institute Bethesda, Maryland I. THE IMPORTANCE OF DECISION MAKING It would be difficult to overstate the importance of the environment as a policy issue. Aside from the ecological implications of decisions in many nonenvironmental policy fields, environmental policies have impacts on other policy fields. The recent controversy over whether protecting the spotted owl should weigh more or less heavily than protecting the jobs of timber industry workers is not going to be...

Health Hazards Associated With General Industry A Chemical Agents

Chemical agents such as solvents or hydrocarbons may have multiple effects on many different body systems. Solvents are ubiquitous at hazardous waste sites therefore, there is a good chance that workers handling hazardous waste will be exposed to one or more solvents. For many of these agents, the adverse effect is seen relatively soon, so the cause of the effect is identifiable with some carcinogenic agents that may cause cancer years later, the link between the agent and the disease is less...

Regulatory Considerations

The management of waste compressed gas cylinders is governed by federal, state, and local regulations. Federal regulations apply to the interstate movement and filling of cylinders. Hazardous waste management and air pollution regulations may be applicable. Local building and fire codes also apply to cylinder use and storage. Federal Department of Transportation (DOT) regulations govern the transportation and refilling of compressed gas cylinders. Under these regulations (found in 49 CFR),...

Set Goals and Targets and Measure Progress Quantitatively

History provides a myriad of examples, large and small, of seemingly impossible tasks accomplished in limited time frames because a dedicated group of people were given a clearly defined goal, adequate resources, and a deadline. Goals for environmental performance have been put forth voluntarily and publicly by numerous firms. In mid-1988, 3M stated that, using 1987 as a baseline, it intended to cut all hazardous and non-hazardous releases to the air, water,...

Tqm And Pollution Prevention

Edwards Deming, an American management visionary, some of the core TQM principles are Top management commitment to quality Zero defects Quality through process improvement, not product inspection Continuous process improvement Measurement of success through statistical methods Team effort Interestingly enough, successful pollution prevention programs also involve the same core principles. Unless there is strong commitment at the top management level (e.g., corporate CEO or...

Source Reduction

Source reduction involves the minimization or elimination of wastes at their source. It often includes changes in procedures rather than in technology or machinery, making it simple, easy, and cost-effective. Because little or no waste is generated, source reduction alleviates the problems associated with handling and disposing of wastes. It is therefore the most desirable option in the waste reduction hierarchy. Operating practices include procedural, administrative, and institutional measures...

Chemistry Of Aqueous Treatment For Control Of Cyanide Chromate And Heavy Metals

The removal of heavy metals as hydroxides or sulfides from aqueous solutions requires the oxidation of cyanide and the reduction of chromate before the precipitation step. Cyanides are oxidized above pH 11 using elemental chlorine (Cl2) or hypochlorite (CIO-) solutions. Rapid decomposition of the intermediate, cyanogen chloride (CNC1), occurs at this high pH with cy-anate (CNO ) as the end product. This compound can be further oxidized to N2 and C02 in a second chlorination step at pH 7.5. Very...

Identification Of Cylinder Contents

Where identification of a compressed gas is necessary, safety of the sampling effort becomes a critical concern. Because of the chemical characteristics of some gases, fire or explosion or other release of toxic gas may occur during sampling. When cylinders or valves have deteriorated, it is very possible to have failures resulting in uncontrolled release of the contents. Procedures and technologies that have historically been used for management of cylinders in poor condition have not always...

The Siallon Process A Overview

The chemistry of the patented 12 Siallon process is simple in that it is a two-stage reaction involving two water-based products. The first step uses a water-based emulsifier that first desorbs the hydrocarbon from the soil and then emulsifies it within a water phase. The second stage is the addition of the Siallon reactive silicate solution to the mixture of soil and emulsified hydrocarbon. The silicate undergoes an acid-base reaction with the emulsifier micelle and is neutralized, forming a...

Siallon Cell Morphology

The evaluation of the physical characteristics of the Siallon silica cell was aimed at answering two questions How durable is the cell and How is the hydrocarbon held within the interior In most cases at least two different analytical or instrumental techniques were employed for each step in order to confirm the answers by separate methods. Samples of motor oil that had been encapsulated with the Siallon process were used as the basis sample for most of the evaluations of morphology. The first...

Column Leach Test Description

When hydrocarbon-contaminated soil that has been treated by the Siallon process is analyzed, the appropriate total concentration analysis is used. These methods will generally involve solvent extraction followed by gas chromatographic analysis, which gives a result that is indicative of the sample as it stands or at a fixed point in time. To assess the effects of both time and groundwater intrusion on Siallon-treated soils an extensive leachability study was undertaken. The study involved more...

Leachability Conclusions

This intensive study of the leachability of hydrocarbons encapsulated with the Siallon process is only a small part of the ongoing research into the durability, integrity, and life span of processed materials. This study did, however, provide a number of significant conclusions as to the behavior of the Siallon silica cell. 1. The Siallon process was effective in encapsulating both diesel fuel and gasoline in sandy soil, sandy silt soil, and clayey soil. 2. The Siallon silica cell is not...

Processes of Decomposition of Refuse in Landfills

Geomorphic Processes

Landfilled material will gradually change in form and will exhibit different engineering and physical properties as a result of various environmental factors. Witmer and coworkers 7,8 reported the garbage decomposition process for a 10-year period as reflected on a particle size distribution curve. The aging process from fresh trash to aged trash along with the environmental and mechanical factors are illustrated in Figure 1. Mechanical processes do not directly contribute to the decomposition...

Case 1 Texas Gulf Coast Industrial Landfill Site

Moldes Flores Papel

Before the advent of horizontal wellbore technology, vertical wells were used to recover contaminated groundwater under landfills. In aquifers with high hydraulic conductivity, vertical wells placed along the periphery of a landfill can influence the aquifer below the landfill. If the size of the plume is small compared to the size of the landfill, migration of contaminants from the core of the plume below the landfill to vertical extraction wells along the periphery spreads the contamination....

Vitrification

Vitrification is a thermal treatment process that uses high temperatures to melt waste material. The melted waste is then fused in glass or another form of synthetic mineral. Organic contaminants are volatilized during the melting process, while the inorganic contaminants are in corporated into the impermeable matrix of the final product. Glass and synthetic silicates offer a safe means of waste disposal because they are very slowly leached by water. The process mandates highly skilled labor...

Selection of Least Hazardous Material Alternatives

This chapter addresses the underlying purposes of accomplishing measures to select the least hazardous of alternative materials used or planned for use by industrial and governmental entities. It then discusses the relationship of substitution processes to other considerations in the decision process. An overview of some approaches for selection methods is presented. A methodology originally developed for the U.S. Navy is described, along with examples. B. Substitution Methods as an Element of...

Municipal Solid Wastes

EPA has funded studies of MSW generation for at least 20 years. In 1960, each person in the United States produced approximately 2.7 lb of trash per day. Today, this number has increased to approximately 4.2 lb per person per day from residences, commercial businesses, and public institutions such as schools and hospitals. Reports are that the average Japanese discards 2.5 lb per day and the average Norwegian 1.7 lb per day, although it is not clear that these data have the same basis as for...

Industrial Wastes

Significant amounts of industrial waste have been reused for generations. About 60 of our domestic production of steel is from scrap, which saves an estimated 1.3 x 1018 J (1.2 x 1015 Btu) per year. Also, significant quantities of scrap iron and steel are exported and returned as finished products. The closer the scrap is to the point of production, the more likely it is to be used. In contrast, U.S. junkyards have a 17-year supply of scrap steel, mostly from discarded automobiles and...

Basic Considerations for Analysis and Design of Landfill Facilities

Municipal refuse or any other industrial waste dumped into a landfill site requires that proper precautions be taken. Technical aspects such as hydrogeological, geohydrological, climatolog-ical, and geotechnical must be examined. However, from the geotechnical engineering viewpoint, the ability of control facilities to mitigate contaminant migration is most important and includes the following considerations Table 1 Comparison of Composition of Urban Refuse Table 1 Comparison of Composition of...

Waste Materials

There are a great variety of types of waste that can cause environmental contamination. Some of the materials commonly encountered are listed below. Liquid Chemicals. Raw materials, waste, and or off-spec liquid chemicals may have been spilled at a site, disposed of in bulk on the ground, or placed in containers such as drums or tanks. Such spillage or disposal can contaminate soil, groundwater, and surface water. Thus, these types of waste may have to be remediated either as bulk materials...

Chemical Solidification And Stabilization Processes

Chemical solidification and stabilization processes are used to treat industrial and hazardous wastes. These processes represent alternatives to ocean disposal or conventional landfilling. Most of these processes originated in the field of radioactive waste control and management. Chemical solidification and stabilization refer to waste treatment that results in the combined effect of 1. Improvement of physical properties (mechanical stabilization) 2. Encapsulation of pollutants (immobilization...

Summary Of Remedial Engineering Technologies

This section presents the identification and evaluation of many available remedial engineering technologies for various environmental media. This presentation is not intended to be comprehensive, but it can serve as a general summary of common remedial technologies. The technologies are grouped into the following broad categories No Action. Monitoring and inspection technologies that do not contribute to actual remediation of site conditions. Institutional Actions. Indirect methods of reducing...

References For Pollution

M., The New Environmental Age, ENR, Pittsfield, Mass., 1992. 2. U.S. Department of Energy, Petroleum Supply Annual 1990, DOE-EIA-0340 (90-91), p. 82. 3. U.S. EPA, Office of Solid Waste, Report to Congress Minimization of Hazardous Waste, EPA 530-SW-86-033, Washington, D.C., 1986. 4. Congress of the United States, Office of Technology Assessment, Serious Reduction of Hazardous Waste, OTA-ITE-318, Washington, D.C., 1986. 5. Anon., Preventing Pollution in the Chemical Industry, Chemical...

Municipal Solid Waste

A municipal solid waste disposal management system may include any combination of sanitary landfill, energy production, and recycling. Historically the collection and transportation of MSW accounts for 75 of the total cost of the waste management system. Landfill1 costs are increasing dramatically as more stringent standards are imposed. Further, the cost of transportation of waste is increasing dramatically as large cities run out of landfill space and the will to site new landfills and, as a...

Thou Shalt Consider the Life Cycle

The last of the commandments is that life cycle economic, environmental, and energy costs must be considered when decisions are made for the management of municipal solid waste. If 'Chlorinated dioxin has 72 isomers that vary in the number of chlorine atoms and their placement in the molecule. 2,3,7,8-Tetradibenzodioxin is the most dangerous of the chlorinated dioxin molecules. The next most significant molecule is 100 times less dangerous. Further, dioxin is degraded by sunlight, with...

General Discussion

There are several ways to dispose of municipal refuse, including incineration and landfilling or, where the nature of the waste permits, by reuse as a substitute construction material. Land-filling is presently the most expedient simple way to manage refuse. Historically, the refuse was referred to as garbage and the landfill was known as the dump. Waste disposal material consists of anything that cannot be further used or recycled economically. As a result, its composition varies from country...

Waste Receiving Handling and Temporary Storage

The process involved in the handling and storage of regulated waste can be summarized as follows. I. Trucks enter the facility through the regulated waste entrance and remain in the regulated waste truck holding area until an unloading bay in the appropriate storage building becomes available. 2. As space becomes available, the trucks are directed to the appropriate building for unloading and testing. 3. Waste is unloaded and tested according to the waste acceptance procedure established at the...

Emissions of Non Methane Organic Compounds

At the hypothetical subject site presented in this chapter, landfill gas is collected and is routed to an enclosed flare. The flare oxidizes any toxic compounds present into less harmful compounds (ideally, carbon dioxide and water). Because landfill gas after combustion has a significantly lower health risk than unburned gas, the choice of the landfill gas collection system efficiency has a large effect on the final estimate of the health risks in the vicinity of the landfill. Emission factors...