Transcript Module 7
MODULE 7 Environment technologies MODULE 7 ENVIRONMENTAL TECHNOLOGIES AIRES (Spain) ETIV - EMAS Technical Implementation and Verification1 1 MODULE 7 Environment technologies This project has been funded with support from the European Commission. This publication reflects the views only of the author, and the Commission cannot be held responsible for any use which may be made of the information contained therein. ETIV - EMAS Technical Implementation and Verification2 2 INTRODUCTION Environment technologies CONTENTS Introduction 1. Waste Management 2. Air Pollution Control 3. Wastewater Control 4. Soil Pollution Control 5. Noise Control 6. Monitoring Technologies ETIV - EMAS Technical Implementation and Verification3 3 INTRODUCTION Environment technologies INTRODUCTION Technology development is key to ensure environmental efficiency and legal compliance when applying EMAS: Links between EMAS and environmental technologies can be summarized in the following aspects: Environmental policy might include the will to use cleaner technologies or Best Available Technology’s Skills and competences of the labour force have to be sufficiently updated and balanced with technology used. Objectives and targets have to be designed taking into account environmental performance (planned and actual) and technology changes. Operational control and non-compliance management require a periodic assessment and review of the technological means. Auditing process and team shall correspond to the technology development of the organization. ETIV - EMAS Technical Implementation and Verification4 4 INTRODUCTION Environment technologies INTRODUCTION Several environmental technologies are presented, covering the following issues: - Waste Air Pollution Wastewater Soil Noise Monitoring • Module covers environmental technologies suitable for small and medium enterprises, public agencies and environmental organizations, taking into account investment costs and know-how. Expensive or high-developed technologies might have not been presented in the module then. ETIV - EMAS Technical Implementation and Verification5 5 WASTE MANAGEMENT Environment technologies 1. WASTE MANAGEMENT ETIV - EMAS Technical Implementation and Verification6 6 WASTE MANAGEMENT Environment technologies CONTENTS • • • • • Background Identification and Classification Techniques Types of waste Selecting technology ETIV - EMAS Technical Implementation and Verification7 7 WASTE MANAGEMENT Environment technologies BACKGROUND • Waste management is one of the most important environmental problem of the world. Exist different technologies to apply to manage the waste that human activities generate. • Best option to combat the wastes accumulation problems, is always the reduce of generation wastes, then the reuse of wastes, and finally the recycling of wastes. Sometimes is necessary the treatment and disposal of wastes. ETIV - EMAS Technical Implementation and Verification8 8 WASTE MANAGEMENT Environment technologies IDENTIFICATION & CLASSIFICATION • Waste is identified and classified according Directive 2000/532/CE, related with the source of waste. • Organization of the waste list is set by codes, giving a two-digit code to type of industry or industrial processes that generate waste. • A four-digit code is associated to subindustrial sectors or subprocesses from waste is generated. • Finally, each type of waste has a six-digit code. ETIV - EMAS Technical Implementation and Verification9 9 WASTE MANAGEMENT Environment technologies TECHNIQUES The techniques used to manage wastes are of three types: • Volume Reduction technologies (mechanical, physical and chemical) • Treatment and disposal of wastes technologies (biodegradation, solidification, stabilization,..) • Ultimate disposal of wastes ETIV - EMAS Technical Implementation and Verification10 10 WASTE MANAGEMENT Environment technologies TECHNIQUES Volume reduction technologies • Concentrating methods as vacuum filtration, rotatory drum pre coat-filter, pressure filtration, centrifuge dewatering thickeners. • Size reduction methods, as hammer mills, shredding machines, crushers, pulverisers and hoggers. Treatment and disposal wastes technologies • Recycling wastes is the most effective technology to prevent the environmental problems. ETIV - EMAS Technical Implementation and Verification11 11 WASTE MANAGEMENT Environment technologies TECHNIQUES • Physical methods of waste treatment as primary treatment, polishing, secondary treatment, disposal resource recovery and discharge recycle. • Chemical treatment as: acid / base neutralization,chemical precipitation, electrolysis, hydrolysis, chemical extraction and leaching, ion exchange • Photolytic reactions as a technique to transform hazardous wastes in arid wastes with free photons of ultraviolet radiation. • Thermal treatment methods of incineration systems like rotary-klin incineration, liquid injection, fixed-hearth incinerators and fluidized bed incinerators. ETIV - EMAS Technical Implementation and Verification12 12 WASTE MANAGEMENT Environment technologies TECHNIQUES • Biodegradation wastes as the process to convert a by biological processes an organic wastes in a inorganic wastes. Processes as biodegradability, aerobic treatment and anaerobic treatment. • Land treatment and composting. Land treatment is the technique to modify the characteristics of soil to treat the wastes inside this. And composting is the technique to biodegrade the wastes introducing the wastes inside the soil, keeping act the natural reactions of the same soil. ETIV - EMAS Technical Implementation and Verification13 13 WASTE MANAGEMENT Environment technologies TECHNIQUES Ultimate disposal of wastes • Landfilling as the technique that dispose the wastes in the land,other techniques are: disposal aboveground, surface impoundment of liquids and deep-well disposal of liquids • Incineration as a ultimate disposal of wastes when the ash of this incineration result arid wastes. ETIV - EMAS Technical Implementation and Verification14 14 WASTE MANAGEMENT Environment technologies TYPES OF WASTES The types of wastes are divided in: • • • • Municipal wastes Medical wastes Hazardous wastes Industrial wastes ETIV - EMAS Technical Implementation and Verification15 15 WASTE MANAGEMENT Environment technologies TYPES OF WASTES Municipal wastes • Determining waste generation. The most commonly used method is the estimating the waste quantity is to weight the waste requiring disposal. The second ,method is to determine the volume of waste which is being generated and use known density factors to convert this into the associated weight. And the third method is to determine the population of the area and then multiply this by typical waste generation factors. • Reuse reduce and recycling these three methods are the most important methods in strategic plans of waste management for municipalities. ETIV - EMAS Technical Implementation and Verification16 16 WASTE MANAGEMENT Environment technologies TYPES OF WASTES • Combustion is one of the most used technology to eliminate waste. Can comprise at same time, different types of incineration systems. • And finally landfilling is the historical method to treat the wastes, but many countries have not sufficient land to keep on involving. Medical Waste • Packaging and storage, is an important factor of this kind of waste, for the condition of infectious waste. • Treatment and disposal of infectious waste with processes as thermal, melting, shredding, grinding, tearing or breaking. ETIV - EMAS Technical Implementation and Verification17 17 WASTE MANAGEMENT Environment technologies TYPES OF WASTES • Incineration, hospital waste incineration involves the application of combustion processes under controlled conditions to convert wastes infectious and pathological material to inert mineral residues and gases. The incineration systems are the same than other type of wastes. • Microwaving, chemical disinfections processes, irradiation processes and plasma systems are other kind of techniques to treat the medical wastes. ETIV - EMAS Technical Implementation and Verification18 18 WASTE MANAGEMENT Environment technologies TYPES OF WASTES Hazardous waste treatment • Physical methods as: separation, filtration, transition, distillation, evaporation, precipitation, transfer, extraction, sorption, membrane separations, reverse osmosis, hyper-and ultra filtration. • Chemical treatments as chemical precipitation, oxidation / reduction Ion exchange, acid / base neutralization and chemical extraction and leaching reduction. • Thermal methods as incineration, the same systems than before. • And biodegradability as a technique to convert the hazardous wastes into a nonhazardous wastes. ETIV - EMAS Technical Implementation and Verification19 19 WASTE MANAGEMENT Environment technologies TYPES OF WASTES Industrial wastes • The methods and techniques to manage the industrial wastes are the same methods and techniques that describe the rest of chapters. • Reduce, reuse and recycling • Reduction methods • Treatment methods • Incineration systems • Landfilling ETIV - EMAS Technical Implementation and Verification20 20 WASTE MANAGEMENT Environment technologies SELECTING TECHNOLOGY • Options for treatment techniques for the various types of waste, types treatment equipment, treatment sites and various waste handling practices all need to be carefully evaluated. • The selection of available options at a facility depends upon a number of factors such as the nature of the waste, the quantity of waste generated, the availability of equipment for treatment on site and of site, regulation constraints, and cost considerations. • We recommend the opinion of environment engineers experts to decide which technique apply in any case. ETIV - EMAS Technical Implementation and Verification21 21 AIR POLLUTION CONTROL Environment technologies 2. AIR POLLUTION CONTROL ETIV - EMAS Technical Implementation and Verification22 22 AIR POLLUTION CONTROL Environment technologies CONTENTS • • • • • Background Equipment Techniques Factors Selecting technology ETIV - EMAS Technical Implementation and Verification23 23 AIR POLLUTION CONTROL Environment technologies BACKGROUND • Controlling the emission of pollutants from industrial and domestic sources is important in protecting the quality of air. Air pollutants can exist in the form of particulate matter or as gases. • Air cleaning devices have been reducing pollutant emissions from various sources for many years. • Originally, air cleaning equipment was used only if the contaminant was highly toxic or had some recovery value. ETIV - EMAS Technical Implementation and Verification24 24 AIR POLLUTION CONTROL Environment technologies EQUIPMENT Equipment used to control particulate emissions are: • Gravity settlers (often referred to as settling chambers) • Mechanical collectors (cyclones) • Electrostatic precipitators (ESPs) • Scrubbers • Fabric filters • Hybrid systems ETIV - EMAS Technical Implementation and Verification25 25 AIR POLLUTION CONTROL Environment technologies EQUIPMENT Gravity settlers (often referred to as settling chambers) • Gravity settlers, or gravity settling chambers, are used industrially for the removal of solid and liquid waste materials from gaseous streams. • Advantages accounting for their use are simple construction, low initial cost and maintenance, low pressure losses, and simple disposal of waste materials. Mechanical collectors (cyclones) • Centrifugal separators, commonly referred to as cyclones, are widely used in industry for the removal of solid and liquid particles (or particulates) from gas streams. ETIV - EMAS Technical Implementation and Verification26 26 AIR POLLUTION CONTROL Environment technologies EQUIPMENT Electrostatic precipitators (ESPs) • They are satisfactory devices for removing small particles from moving gas streams at high collection efficiencies. They have been used almost universally in power plants for removing fly ash from the gases prior to discharge. • Two major types of high-voltage ESP configurations currently used are tubular and plate. Tubular precipitators consist of cylindrical collection tubes with discharge electrodes located on the axis of the cylinder. Vast majority of ESPs installed are of the plate type. • Collected particles are usually removed by rapping. ETIV - EMAS Technical Implementation and Verification27 27 AIR POLLUTION CONTROL Environment technologies EQUIPMENT Scrubbers (venturi scrubbers) • Wet scrubbing involves the technique of bringing a contaminated gas stream into intimate contact with a liquid. • Wet scrubbers include all the various types of gas absorption equipment. • The term "scrubber" will be restricted to those systems which utilize a liquid, usually water, to achieve or assist in the removal of particulate matter from a carrier gas stream. ETIV - EMAS Technical Implementation and Verification28 28 AIR POLLUTION CONTROL Environment technologies EQUIPMENT Fabric filters (bag houses) • Filtration process may be conducted in many different types of fabric filters.Differences may be related to: – – – – Type of fabric Cleaning mechanism Equipment Mode of operation • Gases to be cleaned can be either "pushed" or "pulled" through the bag house. • In the pressure system (push through) the gases may enter through the cleanout, hopper in the bottom or through the top of the bags. • In the suction type (pull through) the dirty gases are usually forced through the inside of the bag and exit through the outside. ETIV - EMAS Technical Implementation and Verification29 29 AIR POLLUTION CONTROL Environment technologies EQUIPMENT • Hybrid systems are defined as those types of control devices that involve combinations of control mechanisms-for example, fabric filtration combined with electrostatic precipitation. • Four of the major hybrid systems found in practice today include: – Wet electrostatic precipitators, – Ionizing wet scrubbers, – Dry scrubbers, and – Electrostatically augmented fabric filtration. ETIV - EMAS Technical Implementation and Verification30 30 AIR POLLUTION CONTROL Environment technologies TECHNIQUES • Applicability of a given technique depends on the physical and chemical properties of the pollutant and the exhaust stream. • More than one technique may be capable of controlling emissions from a given source • Techniques used to control gaseous emissions are: Absorption Adsorption Combustion Condensation ETIV - EMAS Technical Implementation and Verification31 31 AIR POLLUTION CONTROL Environment technologies TECHNIQUES Absorption • Mass transfer operation in which a gas is dissolved in a liquid. • A contaminant (pollutant exhaust stream) contacts a liquid, and the contaminant diffuses from the gas phase into the liquid phase. • The liquid most often used for absorption is water. • Reagents can be added to the absorbing water to increase the removal efficiency of the system. Gas absorbers or wet scrubbers are designed to provide good mixing of the gas and liquid phases. • The devices used for gas absorption are often the same as those used in particulate emission scrubbing. • These include packed towers, plate towers, spray columns, and venturi scrubbers. ETIV - EMAS Technical Implementation and Verification32 32 AIR POLLUTION CONTROL Environment technologies TECHNIQUES Adsorption • Mass transfer process that involves removing a gaseous contaminant by adhering it to the surface of a solid. • It can be classified as physical or chemical. In physical adsorption, a gas molecule adheres to the surface of the solid due to an imbalance of natural forces (electron distribution). • In chemisorption, once the gas molecule adheres to the surface, it reacts chemically with it. • The major distinction is that physical adsorption is readily reversible whereas chemisorption is not. ETIV - EMAS Technical Implementation and Verification33 33 AIR POLLUTION CONTROL Environment technologies TECHNIQUES Combustion • Combustion is defined as rapid, high-temperature gas-phase oxidation. • Simply, the contaminant (a carbon-hydrogen substance) is burned with air and converted to carbon dioxide and water vapor. • The operation of any combustion source is governed by the three T's of combustion; temperature, turbulence, and time. • Combustion devices can be categorized as flares, thermal incinerators, or catalytic incinerators ETIV - EMAS Technical Implementation and Verification34 34 AIR POLLUTION CONTROL Environment technologies TECHNIQUES Condensation • Process in which the volatile gases are removed from the contaminant stream and changed into a liquid. • It is usually achieved by reducing the temperature of a vapor mixture until the partial pressure of the condensable component equals its vapor pressure. • Requires low temperatures to liquefy most pure contaminant vapors. • It is affected by the composition of the contaminant gas stream. • Condensers are normally used in combination with primary control devices. • Condensers can be located upstream of (before) an incinerator, adsorber, or absorber. ETIV - EMAS Technical Implementation and Verification35 35 AIR POLLUTION CONTROL Environment technologies FACTORS • There are a number of factors to be considered prior to selecting a particular piece of air pollution control hardware. Economic Environ mental Engineering ETIV - EMAS Technical Implementation and Verification36 36 AIR POLLUTION CONTROL Environment technologies FACTORS Environmental factors • Equipment location Environ • Available space mental • Ambient conditions • Availability of adequate utilities (i.e., power, water, etc.) and ancillary system facilities (i.e., waste treatment and disposal, etc.) • Maximum allowable emissions (air regulations) • Aesthetic considerations • Contribution of air pollution control system to wastewater and solid waste • Contribution of air pollution control system to plant noise levels ETIV - EMAS Technical Implementation and Verification37 37 AIR POLLUTION CONTROL Environment technologies FACTORS Economic • Capital cost (equipment, installation, engineering, etc.) • Operating cost (utilities, maintenance, etc.) • Expected equipment lifetime and salvage value Economic ETIV - EMAS Technical Implementation and Verification38 38 AIR POLLUTION CONTROL Environment technologies FACTORS Engineering • Contaminant characteristics (i.e., physical and chemical properties, concentration, particulate shape and size) • Gas stream characteristics (i.e., volume flow rate, temperature, pressure, humidity, composition, viscosity, density, reactivity, combustibility, corrosivity, toxicity, etc.) • Design and performance characteristics of the particular control system(i.e., size and weight, fractional efficiency curves, etc) Engineering ETIV - EMAS Technical Implementation and Verification39 39 AIR POLLUTION CONTROL Environment technologies SELECTING TECHNOLOGY • Final choice in equipment selection is usually dictated by that equipment capable of achieving compliance with regulatory codes at the lowest uniform annual cost (amortized capital investment plus operation and maintenance costs). • In order to compare specific control equipment alternatives, knowledge of the particular application and site is essentials. • A preliminary screening, however, may be performed by reviewing the advantages and disadvantages of each type of air pollution control equipment. ETIV - EMAS Technical Implementation and Verification40 40 WASTEWATER CONTROL Environment technologies 3. WASTEWATER CONTROL ETIV - EMAS Technical Implementation and Verification41 41 WASTEWATER CONTROL Environment technologies CONTENTS • • • • • • Background Wastewater treatment principles Wastewater treatment plants Primary treatment Secondary treatment Tertiary treatment ETIV - EMAS Technical Implementation and Verification42 42 WASTEWATER CONTROL Environment technologies BACKGROUND • Basic objective of the field of water quality engineering is the determination of the environmental controls that must be instituted to achieve a specific environmental quality objective • Role of the water quality engineer and scientist is to analyze water quality problems by dividing the problem into its principal components: – Inputs - discharge of residue into the environment from man' s and nature's activities. – Reactions and physical transport - chemical and biological transformations and water movement that result in different levels of water quality at different locations in time in the aquatic ecosystem. – Output - the resulting concentration of a substance, at a particular location in the water body during a particular time of the year or day ETIV - EMAS Technical Implementation and Verification43 43 WASTEWATER CONTROL Environment technologies BACKGROUND • There are several points at which the water quality in a system can be controlled. • The initial concentration at the outfall can be controlled by: – Reducing the effluent concentration of the waste input – Reducing the upstream concentration and effluent volume – Increasing the upstream flow by low flow augmentation • The choice of the mix of the above controls involves issues of: – The costs of the controls - Iocally, regionally, and nationally. – The expected benefits of water quality in water use. – The technological bounds (e.g., available storage for low flow augmentation) on the controls. ETIV - EMAS Technical Implementation and Verification44 44 WASTEWATER CONTROL Environment technologies WASTEWATER TREATMENT PRINCIPLES • If untreated wastewater is allowed to accumulate, the decomposition of the organic materials it contains can lead to the production of offensive odors and gases. • Untreated wastewater contains numerous pathogenic microorganisms, released from the human intestinal system. • It contains nutrients which can stimulate the growth of aquatic life, and it may also contain toxic compounds. • Immediate removal from its sources, followed by treatment and disposal are the priorities when managing wastewater. ETIV - EMAS Technical Implementation and Verification45 Removal Treatment Disposal 45 WASTEWATER CONTROL Environment technologies WASTEWATER TREATMENT PLANT • Purpose of any ww treatment plant is to convert the components in raw wastewater, with its inherent characteristics, into a relatively harmless final effluent for discharge to a receiving body of water and to safely dispose of the solids (sludge) produced in the process. • Wastewater treatment plant must satisfy these conditions : – – – – – requirements for aesthetics and minimization of obnoxious odors at treatment and disposal to prevent contamination of water supplies from physical, chemical, and biological agents; to prevent destruction of fish, shellfish, and other aquatic life; to protect against the spread of disease from crops grown on sewage irrigation or sludge disposal; to encourage other beneficial uses of effluent. ETIV - EMAS Technical Implementation and Verification46 46 WASTEWATER CONTROL Environment technologies WASTEWATER TREATMENT PLANTS • Wastewater treatment plants utilize a number of individual or unit operations and processes to achieve the desired degree of treatment. • Collective treatment schematic is called a flow scheme, a flow diagram, a flow sheet, a process train, or a flow schematic. • Unit operations and processes are grouped together to provide what is known as primary, secondary, and tertiary (or advanced) treatment. Primary (Physical) Secondary (Chemical) Tertiary (Biological) ETIV - EMAS Technical Implementation and Verification47 47 WASTEWATER CONTROL Environment technologies PRIMARY TREATMENT • Treatment methods in which the application of physical forces predominate are known as physical unit operations. • These were the first methods to be used for wastewater treatment. • Screening, mixing, flocculation, sedimentation, flotation, and filtration are typical unit operations for primary treatment processes. Primary Treatment ETIV - EMAS Technical Implementation and Verification48 48 WASTEWATER CONTROL Environment technologies PRIMARY TREATMENT Clarification (Sedimentation) • Process of separating the settleable solids from the liquid • Some treatment systems employing two or more stages of treatment and clarification, the terms primary, secondary, and final clarification are used. • The actual physical sizing of the clarifier (depth, surface area, inlet structure, etc.) is highly dependent upon the quantity and composition of the flow. • Clarification units can be either circular or rectangular and are normally designed to operate on a continuous flowthrough basis: – – circular units are generally called clarifiers, whereas rectangular units are commonly referred to as sedimentation tanks. ETIV - EMAS Technical Implementation and Verification49 49 WASTEWATER CONTROL Environment technologies PRIMARY TREATMENT Flotation • Separates these particles by their density by the introduction of air into the system. • Fine bubbles adhere to, or are absorbed by, the solids, which are then lifted to the surface. • Flotation separator tanks can be either rectangular or circular in shape and constructed of either concrete or steel • It is an appropriate technology for treating suspended solids and oil and grease in industrial waters. Process will achieve 40-65% suspended solids removal and 60% of oil and grease removal. ETIV - EMAS Technical Implementation and Verification50 50 WASTEWATER CONTROL Environment technologies PRIMARY TREATMENT Oil-Water separation • In practically all manufacturing industries, oil and grease can be found in a plant's wastewater • The configuration of the separator is that of a flow-through tank. The basic principle by which oil-water separators work is the differential between the specific gravities of water and the oils to be removed. • Major advantage of oil-water separators is their ability to treat wastewater which is heavily laden with oil compounds. • They represent a very simple treatment operation which minimizes personnel requirements; its operating costs are minimized. • It results in a more "pure" oil which can make recycling much easier. ETIV - EMAS Technical Implementation and Verification51 51 WASTEWATER CONTROL Environment technologies SECONDARY TREATMENT • Treatment methods in which the removal or conversion of contaminants is brought about by the addition of chemicals or by other chemical reactions are known as chemical unit processes. • Precipitation, gas transfer, adsorption, and disinfections are the most common examples used in secondary wastewater treatment. Secondary Treatment ETIV - EMAS Technical Implementation and Verification52 52 WASTEWATER CONTROL Environment technologies SECONDARY TREATMENT Coagulation - precipitation • Involves two discrete steps. • Rapid mixing is employed to ensure that the chemicals are thoroughly dispersed • Next, the wastewater undergoes flocculation which provides for particle contact, so that the particles can agglomerate to a size large enough for removal. • Finally precipitation occurs, that is really the same as settling. ETIV - EMAS Technical Implementation and Verification53 53 WASTEWATER CONTROL Environment technologies SECONDARY TREATMENT • Coagulation-precipitation is capable of removing from industrial wastewater pollutants such as BOD, COD, and TSS. It can remove additional pollutants such as phosphorus, nitrogen compounds, and metals. This technology is attractive to industry because a high degree of classification and toxic pollutants removal can be combined in one treatment process. Neutralization • Involves adding an acid or a base to a wastewater to offset or neutralize the effects of its counterpart in the wastewater flow, namely, adding acids to alkaline wastewaters and bases to acidic wastewaters. ETIV - EMAS Technical Implementation and Verification54 54 WASTEWATER CONTROL Environment technologies SECONDARY TREATMENT • The most important considerations in neutralization treatment are the wastewater constituents so that the proper neutralizing chemicals are used, and proper monitoring to ensure that the required quantities of these chemicals are used and that the effluent is in fact neutralized. • For acid waste streams, lime, soda ash, and caustic soda are the most common base chemicals used • In alkaline waste streams, sulfuric, hydrochloric, and nitric acid are generally used for neutralization ETIV - EMAS Technical Implementation and Verification55 55 WASTEWATER CONTROL Environment technologies TERTIARY TREATMENT Tertiary Treatment • Treatment methods in which the removal of contaminants is brought about by biological activity are known as biological unit processes. • Biological treatment is used primarily to remove the biodegradable organic substances (colloidal or dissolved) in wastewater. • Basically these substances are converted into gases that can escape to the atmosphere or into biological cell tissue that can be removed by settling. • Designed to remove those constituents that are not adequately removed in the secondary treatment plants, such as N, P, and other soluble organic and inorganic compounds. ETIV - EMAS Technical Implementation and Verification56 56 WASTEWATER CONTROL Environment technologies TERTIARY TREATMENT • Many of these constituents must be removed to meet stringent water quality standards and to allow reuse of the effluent for municipal, industrial, irrigation, recreation, and other water needs. • The most commonly used advanced wastewater treatment processes are among other: – – – – – – – Chemical precipitation of phosphorus, Nitrification and Denitrification, Ammonia stripping, Breakpoint chlorination, Filtration, Carbon adsorption, Ion exchange ETIV - EMAS Technical Implementation and Verification57 57 WASTEWATER CONTROL Environment technologies TERTIARY TREATMENT Aerobic Suspended Growth Processes (Activated Sludge) • Process in which the biological growth products (microorganisms) are kept in suspension in a liquid medium consisting of entrapped and suspended colloidal and dissolved organic and inorganic materials. • It uses metabolic reactions of the microorganisms to attain an acceptable effluent quality by removing these substances exerting an oxygen demand. • In the suspended growth processes, wastewater enters a reactor basin, concretesteel-earthen tank(s) where microorganisms are brought into contact with the organic components of the wastewater by some type of mixing device. ETIV - EMAS Technical Implementation and Verification58 58 WASTEWATER CONTROL Environment technologies TERTIARY TREATMENT Aerobic Lagoons (Stabilization Ponds) • Large, shallow earthen basins that are used for wastewater treatment by utilizing natural processes involving both algae and bacteria. The objective is microbial conversion of organic wastes into algae. Aerobic conditions prevail throughout the process. • In aerobic photosynthesis, the oxygen produced by the algae through the process of photosynthesis is used by the bacteria in the biochemical oxidation and degradation of organic waste. Carbon dioxide, ammonia, phosphate, and other nutrients released in the biochemical oxidation reactions are, in turn, used by the algae, forming a cyclicsymbiotic relationship. ETIV - EMAS Technical Implementation and Verification59 59 WASTEWATER CONTROL Environment technologies TERTIARY TREATMENT • Aerobic lagoons are used for treatment of weak industrial wastewater containing negligible amounts of toxic and for non-biodegradable substances. Anaerobic Lagoon • Earthen ponds built with a small surface area and a deep liquid depth of 3-7 m. They are anaerobic throughout their depth, except for an extremely shallow surface zone. • Raw wastewater enters near the bottom of the lagoon (often at the center) and mixes with the active microbial mass in the sludge blanket. ETIV - EMAS Technical Implementation and Verification60 60 WASTEWATER CONTROL Environment technologies TERTIARY TREATMENT • Discharge is located near one of the sides and submerged below the liquid surface. Excess undigested grease floats to the top. Excess sludge is washed out with the effluent. • Anaerobic lagoons are effective prior to aerobic treatment of high-strength organic wastewater that also contains a high concentration of solids. BOD removal efficiencies of up to 85% are possible. ETIV - EMAS Technical Implementation and Verification61 61 SOIL POLLUTION CONTROL Environment technologies 4. SOIL POLLUTION CONTROL ETIV - EMAS Technical Implementation and Verification62 62 SOIL POLLUTION CONTROL Environment technologies CONTENTS • • • • Background Techniques Soil Removal In-situ treatment ETIV - EMAS Technical Implementation and Verification63 63 SOIL POLLUTION CONTROL Environment technologies BACKGROUND • Contaminated soils is one of the environmental problems historically ignored by humans. Lately, its relation with human health’ safety and ecological impacts was discovered. • Most widely used techniques applied to polluted soils are removal and placement in a more secure landfill environment. ETIV - EMAS Technical Implementation and Verification64 64 SOIL POLLUTION CONTROL Environment technologies BACKGROUND • Although this simply moves contaminated soil from one place to another, it can be of significant benefit due to improvements in landfill design. • Often early landfills were sited in wetlands or adjacent to rivers and encouraged contaminant migration and ultimately exposure to at-risk populations. ETIV - EMAS Technical Implementation and Verification65 65 SOIL POLLUTION CONTROL Environment technologies BACKGROUND • Wastes could be stabilised after removal and before or during placement to further reduce mobility after placement. • Stabilisation might include solidification with concrete or a similar material or direct chemical treatment of certain contaminants. • Incineration or thermal treatment of the contaminated soil could be used to eliminate organic contaminants susceptible to destruction or removal by these means. ETIV - EMAS Technical Implementation and Verification66 66 SOIL POLLUTION CONTROL Environment technologies BACKGROUND • A variety of other processes have been employed to treat contaminated soils once excavated and removed from a site. Included among these are biological degradation in dedicated bioreactors and sophisticated extraction schemes, for example, supercritical extraction, followed by the application of destruction processes to the effluent. • An alternative to removal options of remediating soil is the use of in situ means that do not require soil removal. These are generally the options of choice if they can be demonstrated effective at reducing the volume, toxicity, or exposure to the wastes. ETIV - EMAS Technical Implementation and Verification67 67 SOIL POLLUTION CONTROL Environment technologies TECHNIQUES The principle option to decontaminate soils are: • Removal options for soil remediation • In situ soil remediation processes ETIV - EMAS Technical Implementation and Verification68 68 SOIL POLLUTION CONTROL Environment technologies TECHNIQUES Removal options for soil remediation • These techniques are techniques that consists in to take the contaminated soil and apply a method to decontaminate. This techniques are: Incineration, landfilling, stabilization and solidification, and ex situ bioremediation. • The methods are the same that are defined in the waste manager chapter. ETIV - EMAS Technical Implementation and Verification69 69 SOIL POLLUTION CONTROL Environment technologies TECHNIQUES In situ soil remediation processes • These techniques consist in treat the soil in the same land or place where is contaminated. The techniques or methods are: Pump and treat extraction of contaminated groundwater, enhancement of pump and treat processes, vacuum extraction in the unsaturated zone and in situ bioremediation of soils. • Pump and treat extraction of contaminated groundwater is the technique that remove the contaminated groundwater or separate contaminated phases via withdrawal wells for above-ground treatment. ETIV - EMAS Technical Implementation and Verification70 70 SOIL POLLUTION CONTROL Environment technologies TECHNIQUES • Enhancement of pump and treat processes are methods of remediation of soils. These methods are of limited usefulness when significant quantities of NAPLs exist. • Due to the low solubility of most soil contaminants, large volumes of water are required to remove contaminants present in a separate phase even if it were possible to maintain the water at saturation. ETIV - EMAS Technical Implementation and Verification71 71 SOIL POLLUTION CONTROL Environment technologies TECHNIQUES • Vacuum extraction in the unsaturated zone is a process that is similar conceptually to pump and treat of groundwater is soil vacuum extraction (SVE) in the water-unsaturated zone. • A vacuum is applied to the unsaturated zone by placing a vacuum pump on a well screened in the unsaturated zone. This pulls vapours through the soil, removing any volatile components that have volatilised in the subsurface ETIV - EMAS Technical Implementation and Verification72 72 SOIL POLLUTION CONTROL Environment technologies TECHNIQUES • In situ bioremediation of soils is perhaps the most desirable of all treatment processes is in situ biodegradation to render the soil harmless and to naturally recycle the contaminants. • There are a number of compounds that undergo detoxification by microbial processes at rates that are sufficient to justify natural recovery of contaminated soils. ETIV - EMAS Technical Implementation and Verification73 73 NOISE CONTROL Environment technologies 5. NOISE CONTROL ETIV - EMAS Technical Implementation and Verification74 74 NOISE CONTROL Environment technologies CONTENTS • • • • • • Background Noise control Guidelines Control techniques Results Noise control for new projects ETIV - EMAS Technical Implementation and Verification75 75 NOISE CONTROL Environment technologies BACKGROUND • Noise pollution is traditionally not placed among the top environmental problems facing the society; however, it is one of the more frequently encountered sources • Sources of noise pollution are extremely diverse and are constantly increasing as more and more noisegenerating products become available to consumers. • An estimated 6% citizens are exposed to noise that poses a threat to their hearing. • In today's mechanized world it is virtually impossible for an active person to avoid exposure to potentially harmful sound levels. ETIV - EMAS Technical Implementation and Verification76 76 NOISE CONTROL Environment technologies NOISE CONTROL • General control measures include alteration of machines and equipment to gather up-dated machinery regarding noise prevention. • Noise can be tackled through: Reduction at source Change to quieter methods Prevention or reduction of propagation ETIV - EMAS Technical Implementation and Verification77 77 NOISE CONTROL Environment technologies NOISE CONTROL Reduction at source • It is often possible to reduce noise radiation from production equipment, material handling, and work in progress; for example by damping sound radiating panels, quietening power sources and transmissions, and reducing noise from compressed air exhausts. • Sometimes machine alterations or enclosures do not give sufficiently good results, and if it is the work process itself which causes intense noise it can be difficult to predict the results of noise control measures. • In such cases effort might be better aimed at changing the working methods and processes themselves. ETIV - EMAS Technical Implementation and Verification78 78 NOISE CONTROL Environment technologies NOISE CONTROL Change to quieter methods • Changing the method of work is the only way to get to grips with noise generation; it requires that production equipment or part of it must be replaced and one must be aware of the availability of less noisy equipment for both production and material handling. • Requires cooperation between the buyer, supplier, designer, and safety organization. ETIV - EMAS Technical Implementation and Verification79 79 NOISE CONTROL Environment technologies NOISE CONTROL Prevention or reduction of propagation • Prevent propagation to avoid noise pollution can result economically more efficient than corrective measures. • The noise in a workshop is often dominated by a relatively small number of intense noise sources.Try to enclose all noise sources points or keep them away from workers in the same room. • By setting up sound absorbing ceiling and wall panels, noise levels within the room far from the noise sources can be reduced. • Alteration and replacement of production equipment may mean that personnel monitoring this machinery do not need to be in its vicinity if monitoring can be carried out in a sound insulated control room. ETIV - EMAS Technical Implementation and Verification80 80 NOISE CONTROL Environment technologies NOISE GUIDELINES • For all noise control efforts a target noise level must be set. Type of room Highes sound level • A highest level must guideline (dB) Conference room 35 be defined for each Office 40 place of equipment or room Guideline noise levels for specific locations Workshop office, rest room 45 Laboratory, measurement room 50 Canteen 50 Changing room 55 Repair shop 60 Production areas 75 Fan room, compressor room 90 ETIV - EMAS Technical Implementation and Verification81 81 NOISE CONTROL Environment technologies NOISE CONTROL TIPS • Machinery have to be adapted to new normative, relevant materials of the machines are key to ensure appropriate noise levels. • Existing equipment must be attenuated without complicated operations. • Handling material can be done by consider choosing conveyor belts and controlling the speed of conveyor belt transports. • Enclosure of machines can reduce noise levels at its source very effectively. • Attenuation by using absorbent materials is one of the key techniques to ensure that rooms and workshops do not communicate noise pollution to each other. To ensure so, best practices are providing sound isolated rooms. ETIV - EMAS Technical Implementation and Verification82 82 NOISE CONTROL Environment technologies RESULTS for NOISE CONTROL • Mounting an absorbent roof or ceiling in a room will in general give a noise reduction of between 3 and 5 dB. Exceptionally, up to 10 dB can be obtained. • Damping of vibration of small production machines by applying damping material can give between 3 and 10 dB attenuation. • Factory-made screens can reduce noise from between 5 and 15 dB. • Leakage where pipes pass through walls as well as acoustic leaks between walls, screens or enclosures, can produce large variations in the attenuation achieved. It is therefore important to seal air gaps carefully. ETIV - EMAS Technical Implementation and Verification83 83 NOISE CONTROL Environment technologies NOISE CONTROL at NEW PROJECTS • Noise control of new projects can be difficult to manage and implement, but very cost-effective at the long term. • Implementing noise reduction measures at rooms, planning the building and purchase accurate machinery are necessary steps to execute a program for noise control. • Noise abatement measures at the municipality level can reduce the background noise and establish an adequate framework to develop a detailed building code regarding noise reduction ETIV - EMAS Technical Implementation and Verification84 84 MONITORING TECHNOLOGIES Environment technologies 6. MONITORING TECHNOLOGIES ETIV - EMAS Technical Implementation and Verification85 85 MONITORING TECHNOLOGIES Environment technologies CONTENTS • • • • • • • • • Background Selecting methodology Water sampling Groundwater sampling Soil sampling Air sampling Noise sampling Sampling packment and shipment Databases and scientific journals ETIV - EMAS Technical Implementation and Verification86 86 MONITORING TECHNOLOGIES Environment technologies BACKGROUND • In many instances, we are unaware that a problem exists until harm has been done. Damage may be in the form of disease to the surrounding population or destruction of the surrounding ecosystem. Monitoring problem areas or potential problem areas can help to limit future damage. • Before beginning any sampling program, background research must be conducted to determine: - proper equipment for both sampling and personal protection, proper sampling methodology and analytical methods, and appropriate health and safety practices to be employed. This is especially important when handling materials which may be hazardous or radioactive. ETIV - EMAS Technical Implementation and Verification87 87 MONITORING TECHNOLOGIES Environment technologies SELECTING METHODOLOGY Methods used to obtain data regarding contamination of soil, air, and water , have to take into account the following factors: - The program objective (documenting exposures. determining regulatory compliance The type of material to be sampled (soil, vegetation, air, water, sludge, etc.). The physical and chemical properties of the contaminant. Other contaminants that affect the results. Regulatory requirements and safety Costs Reliability. Scale of sample area (small-scale site related to individual persons versus a large-scale site). Short- versus long-term sampling requirement ETIV - EMAS Technical Implementation and Verification88 88 MONITORING TECHNOLOGIES Environment technologies SAMPLING Several factors must be accomplished to carry on an adequate sampling practice: samples must represent the conditions existing at the point taken. samples must be of sufficient volume and must be taken frequently enough to permit reproducibility of testing requisite for the desired objective, as conditioned by the method of analysis to be employed. the samples must be collected, packed, shipped, and manipulated prior to analysis in a manner that safeguards against change in the particular constituents or properties to be examined. ETIV - EMAS Technical Implementation and Verification89 89 MONITORING TECHNOLOGIES Environment technologies WATER SAMPLING • Water sampling methodologies include: - Grab sample - Composite sample - Continuous flowing sample • Collection of a grab sample of water at a specific site representing conditions only at the time of sampling. Applicable to sampling water from sources such as wells, rivers, streams, lakes and oceans for chemical, physical, bacteriological, or radiological analysis • Collection of a composite sample at a specific site, portions of which are collected at varied time intervals. Alternatively, the composite may consist of portions collected at various sites or may consist of a combination of both site and time variables. ETIV - EMAS Technical Implementation and Verification90 90 MONITORING TECHNOLOGIES Environment technologies WATER SAMPLING • Continuous flowing sample, from one or more sampling sites, suitable for on-stream analysers. Applicable to sampling water from sources such as wells, rivers, streams, lakes, oceans, and reservoirs on a continual basis for chemical, physical, or radiological analyses • Apparatus used are: - Delivery valve or pump. - Piping system. - Flow regulation system - Waste disposal system. ETIV - EMAS Technical Implementation and Verification91 91 MONITORING TECHNOLOGIES Environment technologies GROUNDWATER MONITORING • It is developed by delineating contamination plumes, and establishing the integrity of hazardous material management facilities. • Goal in sampling groundwater monitoring wells is to obtain samples that are truly representative of the aquifer or groundwater in question. • Water that stands within a monitoring well for a long period of time may become unrepresentative of formation water because chemical or biochemical change may cause water-quality alterations; and even if it is unchanged from the time it entered the well, the stored water may not be representative of formation water at the time of sampling. ETIV - EMAS Technical Implementation and Verification92 92 MONITORING TECHNOLOGIES Environment technologies SOIL SAMPLING • Two portions of the soil that are important to the environmental scientist: - 0-15 cm layer - Upper meter • The surface layer (0-15 cm) reflects the deposition of airborne pollutants, especially those recently deposited pollutants. Pollutants that have been deposited by liquid spills or by long-term deposition of water-soluble materials may be found at depths ranging up to several meters. Plumes emanating from hazardous waste dumps or from leaking storage tanks may be found at considerable depths. • The methods of sampling each of these are slightly different, but all make use of one of two basic techniques. ETIV - EMAS Technical Implementation and Verification93 93 MONITORING TECHNOLOGIES Environment technologies SOIL SAMPLING DEVICES • Samples can be collected with some form of core sampling or auger device, or they may be collected by use of excavations or trenches. In the latter case, the samples are cut from the soil mass with spades or short punches. • Techniques that are utilized should be closely coordinated with the analytical laboratory in order to meet the specific requirements of the analytical methods used. ETIV - EMAS Technical Implementation and Verification94 94 MONITORING TECHNOLOGIES Environment technologies SURFACE SOIL SAMPLING • Use of a punch or thin-walled steel tube that is 15-20 cm long to extract short cores from the soil. Tube is driven into the soil with a wooden mallet; the core and the robe are extracted; and the soil is pushed out of the tube into a stainless steel mixing bowl. • Using a seamless steel ring, approximately 15-30 cm in diameter, the ring is driven into the soil to a depth of 15-20 cm. The ring is extracted as a soilring unit, and the soil is removed for analysis. • Perhaps the most undesirable sample collection device is the shovel or scoop. Often used in agriculture, but where samples are being taken for chemical pollutants, the inconsistencies are to be great. ETIV - EMAS Technical Implementation and Verification95 95 MONITORING TECHNOLOGIES Environment technologies SHALLOW SURFACE SAMPLING • Sampling pollutants that have moved into the lower soil horizons requires the use of a device that will extract a longer core than can be obtained with the short probes or punches. • Three basic methods are used for sampling these deeper soils - Soil probes or soil augers - Power-driven corers - Trenching • Samples should be collected at least every 1.5 m or in each distinct stratum. Additional samples should be collected where sand lenses or thin silt and sand lovers appear in the profile. ETIV - EMAS Technical Implementation and Verification96 96 MONITORING TECHNOLOGIES Environment technologies AIR SAMPLING • Investigations of atmospheric contaminants involve the study of a heterogeneous mass under uncontrolled conditions. Interpretation of the data derived from the air-sampling program must often be based on the statistical theory of probability. • Extreme care must be observed to obtain measurements over a sufficient length of time to obtain results that may be considered representative. • Choice of sampling techniques and measurement methodology, the characteristics of the sites, the number of sampling stations, and the amount of data collected all depend on the objectives of the monitoring program ETIV - EMAS Technical Implementation and Verification97 97 MONITORING TECHNOLOGIES Environment technologies AIR SAMPLING OBJECTIVES TREND ANALYSIS POLLUTION ABATEMENT PROGRAMS ANALYSIS AIR QUALITY CRITERIA and STANDARD SETTING AIR SAMPLING OBJECTIVES HEALTH and VEGETATION EFFECTS STUDIES BACKGROUND EVAUATIONS ACTIVATION of EMERGENCY PROCEDURES CONTROL REGULATIONS ENFORCEMENT DEVELOPMENT of AIR POLLUTION CONTROL STRATEGIES ETIV - EMAS Technical Implementation and Verification98 98 MONITORING TECHNOLOGIES Environment technologies AIR SAMPLING FACTORS • The topography, demography, and micrometeorology of the area, as well as the contaminant measured, must be considered in determining the number of monitoring stations required in the area. • A map of the locations of the sampling stations is desirable in describing the sampling station. • Multiple samplers or monitors operating simultaneously upwind and downwind from the source are often very valuable and efficient. • Choice of procedure for the air sampling is dependent on the contaminant to be measured. ETIV - EMAS Technical Implementation and Verification99 99 MONITORING TECHNOLOGIES Environment technologies AIR SAMPLING GUIDELINES • The height of the inlet to the sampling duct should normally be from 2.5 to 5 m above ground whenever possible. • Height of the inlet above the sampling station structure or vegetation adjacent to the station should be greater than 1 m. • Sampling should preferably be through a vertical inlet with an inverted cone over the opening. • For a horizontal inlet, there should be a minimum of 2 m from the face of the structure. ETIV - EMAS Technical Implementation and Verification 100 100 MONITORING TECHNOLOGIES Environment technologies AIR SAMPLING GUIDELINES • For access to representative ambient air in the area sampled, the elevation angle from the inlet to the top of nearby buildings should be less than 30°. • To be representative of the area in which a large segment of the population is exposed to contaminants emitted by automobiles, the inlet should be at a distance greater than 15 m from the nearest high-volume traffic artery. • Photochemical oxidants or ozone samplers should be located at distances greater than 50 m from highvolume-traffic locations. • Particulate matter samplers should be sited at locations that are greater than 200 m from unpaved streets or roads. ETIV - EMAS Technical Implementation and Verification 101 101 MONITORING TECHNOLOGIES Environment technologies NOISE SAMPLING • To avoid noise pollution, it is very relevant to have an appropriate estimation of noise level at the place of work through modern and accurate techniques and measuring tools. • Background noise can be very relevant at factories located around main highways, close to the airports. • Sound-level meter is best used attached to the person exposed. • Noise sampling has to take into account internal and external measures to the workplace ETIV - EMAS Technical Implementation and Verification 102 102 MONITORING TECHNOLOGIES Environment technologies SAMPLES PACKMENT and SHIPMENT • Laboratory for analysing a sample should be consulted regarding packaging requirements before the initiation of a sampling program. Samples must be packaged for shipment in compliance with current legislation and commercial carrier regulations. • Traffic reports, dioxin shipment records, packing lists, chain-of-custody records, and any other shipping/sample documentation accompanying the shipment must be enclosed to a waterproof plastic bag and taped to the underside of the shipping cooler lid. • Coolers must be sealed with custody seals. • Shipping coolers must have clearly visible return address labels on the outside. Inside the cooler, sample containers must be enclosed in clear plastic bags through which sample tags and labels are visible. ETIV - EMAS Technical Implementation and Verification 103 103 MONITORING TECHNOLOGIES Environment technologies SAMPLES PACKMENT and SHIPMENT • Samples for organics analysis must be shipped urgently. • Each sample must be properly documented to ensure timely, correct, and complete analysis for all parameters requested, and, most importantly, to support use of sample data in potential enforcement actions concerning a site. • Documentation system provides the means to individually identify, crack, and monitor each sample from the point of collection through final data reporting • To render sample data valid for enforcement uses, individual samples must be traceable continuously from the time of collection until the time of introduction as evidence during litigation. One mechanism utilized is the use of the "sample tag." ETIV - EMAS Technical Implementation and Verification 104 104 MONITORING TECHNOLOGIES Environment technologies SAMPLES PACKMENT and SHIPMENT Sampling information recorded on an sample tag includes: - Sample number Station number Date. Time Station location Samplers Tag number Lab sample number ETIV - EMAS Technical Implementation and Verification 105 105 MONITORING TECHNOLOGIES Environment technologies DATABASES and JOURNALS • Environmental databases and scientific journals shall complement information provided in this module when dealing with application of environmental technologies. • Main European environmental database is linked to EEA’s website, classified by theme and sector. SERIS presents national reports on the state of the environment • Several scientific journals can be browsed in internet to assess a specific technology suitable for your organization. ETIV - EMAS Technical Implementation and Verification 106 106