An Interactive Energy Management Tool
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An Interactive Energy Management Tool
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Almost any operation will generate some sort of waste. Even non-industrial type of a business will have waste in terms of paper, cardboard etc.. If the waste is land filled, it is rather obvious that the space available is limited. If the waste is incinerated, a secondary waste whether in form of unwanted, though more acceptable, substances or at least heat is created. Waste generators need to concentrate on the waste reduction at the source, if that is not possible, recycling is the second choice, and as the last resort, treatment of wastes, which will give relatively harmless products. The information we provided below, by no means, is exhaustive and no case studies are also given as this topic covers all industries. Waste generation and management Management of waste related activities, like any other activities, must be conceptualized before any action is taken. All the variables have to be known, including projected amount of waste in the future. The technologies available have to be evaluated. This represents landfills, pulverization, incineration, magnetic separation, paper and plastics recovery, composting, gasification, anaerobic digestion and so on. After evaluating all options, the overall strategy in waste management has to be formulated and should be based on the most beneficial technology available. It is advisable, since the economic and political climate might change, to review the chosen strategy periodically and with respect to all existing laws (especially new which could have been enacted after a strategy was selected). Types of waste generated Everyday industry uses products containing hazardous materials. Products like:
If a non-hazardous waste or material is mixed with a hazardous waste, the mixture becomes hazardous. For example, when sawdust absorbent is used to clean up hazardous spills in a shop, the sawdust then becomes a hazardous waste. In addition, unused hazardous material that becomes too old to be used also becomes hazardous waste. Good management supervision and employee training will help reduce waste in these areas. Typical operations using materials which generate hazardous wastes Typical processes or operations, which generate hazardous wastes, are listed below with the type of waste produced. Oil and grease removal generates:
Parts and equipment cleaning generates:
Rust removal generates:
Paint preparation generates:
Painting generates:
Spray booth, spray guns, and brush cleaning generates:
Paint removal generates:
Waste Reduction To be successful, waste reduction programs must be organized. It is not hard to organize waste reduction, but owners and managers will need to spend a little bit of time at first to get started. Keep in mind the following seven principles of waste reduction. 1. Management must be committed to waste reduction for it to work. 2. Businesses should know the types of hazardous waste they generate, how it is produced, and how much is produced. 3. Businesses should know how the hazardous wastes are managed and how much present waste management costs. 4. "Good housekeeping" reduces spills and other waste. 5. Store different waste types in different containers. 6. Train all employees in hazardous waste handling and waste reduction methods. 7. Be aware of the hazardous materials regulations that apply to the business. Someone should be assigned to keep track of environmental regulations.
The five main waste streams generated by industry include:
Solvent Wastes Parts cleaning operations usually generate spent solvent waste in the form of solvent sink mineral spirits and immersion cleaner solvent. Other solvents may include other types of degreasers and paint thinners. If generators spill these materials or use them for purposes other than parts cleaning, degreasing or removing paints, they may generate additional unnecessary waste. Solvents also evaporate easily. The use of solvent sinks for parts washing either on an owned or leased basis is being accepted as general good practice. Solvent reuse and waste containment are ideal features in this practice. The economics of the contracted service are also favorable, considering the current on-site labor costs for equipment maintenance and off-site disposal. The addition of drip trays to both solvent sinks and hot tanks would be beneficial to capture any losses. These are due to spillage as well as unauthorized uses (e.g. floor cleaning) for the solvent where the solvent is not recovered. Water-Based (Aqueous) Wastes Aqueous hazardous wastes refer to water-based detergent wastes and waste sump solids that are hazardous because they contain caustics, high levels of metals, and/or oily dirt. These wastes are typically generated by parts washing equipment. If a business uses a jet spray washer; hot tank, or spray cleaner, it probably generates aqueous detergent waste, aqueous caustic detergent waste, and/or waste sump solids. The majority of the heavy metal residue, oil and grease removed from hot tank operations occur after the actual hot tank use. The heavier concentrations of waste residues are found in the waste sump. Standard practice currently is to use a high-velocity spray wand to dislodge these wastes as necessary. This can be done by use of a solids collection tray with overflow to the sump or periodic cleanout of the sump by a waste hauler for disposal at a permitted TSD facility. The bulk of the oil, grease, and heavy metal residues which are removed in jet spray parts cleaning operations. This occurs with the initial exposure to the wash solutions. In certain repair operations where there are a substantial quantity of parts to be processed, a two stage cleaning operation would provide clean parts in shorter times by using two washing devices in series. The first device would remove the heaviest residue, and the second device would provide the finish cleaning. The following are reduction practices concerning these types of wastes. Use a jet spray with a detergent only solution instead of a caustic-based solution. This trend is continuing with the changeover to aluminum parts in place of ferrous metals which require caustic solutions. The waste solution from the washer is hazardous if it contains metals or oily dirt. Consider pre- washing parts to reduce contamination of the washing solution. Or, try using two hot tanks, one with detergent solution only for aluminum parts, and one containing caustic detergent solution for all other types of parts. Place an inexpensive steel tray or pan next to the tank and drain the parts in the tray for a few minutes after cleaning them. Carefully empty any detergent remaining in the tray back into the tank. Designate a set of bays as primarily intended for service requiring hot tank or jet spray parts cleaning and locate the equipment near these bays. This will help reduce spills and drips within the shop, reducing floor-cleaning waste. To extend the life of the cleaning solution and clean parts faster, consider an extra tank which would contain partially spent solution for rinsing most of the dirt and grime off the parts. Or, use a non-heated tank with partially spent solution for pre-rinsing. If a hot tank does not have heating elements on the bottom of the tank, the solids can easily be removed from the solution to extend the life of the cleaning solution. If the cleaning solution has become weak, the solution can be tested and more detergent or caustic material added as needed. Some equipment leasing services will provide this maintenance service for the tanks the business owns. Screening the solids before they reach the sump will reduce future sump cleaning costs. A leased system can be easier to use since new detergent compounds, tank maintenance, and waste management are included in the price of the service. A disadvantage to leasing is that it can be costly. Purchasing equipment is another option for parts cleaning. However, a business must make certain that its waste storage, transportation, and disposal techniques are safe and legal. Some equipment leasing services will provide raw material supply and waste removal services for tanks that the business owns If a business owns parts cleaning equipment and transports the waste off-site for recycling, treatment, or disposal, the generator must have a registered hazardous waste hauler remove the aqueous caustic detergent waste. If the plant is large and owns a hot tank or jet spray washer equipment, an on-site aqueous waste treatment system may be cheaper than off-site disposal. Paint Wastes One of the most direct means of reducing paint waste is to use low-toxicity paints, i.e. water-based or non-metal products. Using water based paints helps to reduce the use of organic solvents, which become hazardous wastes and also a source of air pollution. Another approach the waste reduction is to use mechanical paint stripping. Substituting with bead blasting or cryogenic coating processes can help avoid caustics and solvents. Various approaches to improve paint application:
Used Oils There are several oil loss reduction practices and used oil recycling technologies that may be useful for minimizing the disposal of waste oil. Oil wastes are generated primarily by the following industrial applications.
The amount of oil generated in a particular process can be decreased or sometimes eliminated by modifying or completely changing a given process. Water-based coolants and fluids often perform equally or better than similar oil-based fluids. Waste oil concentrated at the source of generation helps to segregate types of oils and oily water and reduces the risk of contamination with other hazardous materials. Simple treatment, such as gravity settling, promotes the separation of oil/water wastes to substantially reduce the volume of waste oil. A void using more of the oil product than is necessary and adopt practices for using and re-using materials as much as possible. As in many cases, adopting better housekeeping practices, which require very little cost, can have a large effect on the amount of waste oil produced. Some of these practices include:
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Waste