Page 258 - Demo

Safety Reference
1-800-452-1261
256
#26a Solid Waste Disposal in Landfill
The majority of inorganic solid wastes are salts consisting of a cation and an anion. In planning the disposal of these inorganic salts, the hazards associated with the cation and anion must be determined sepa- rately. If either part presents a potential hazard, the substance should not be disposed of in a municipal landfill.
Cations that have a relatively low level of toxicity are: Al, Bi, Ca, Cu, Fe, Li, Mg, Mo(VI), K, Sc, Na, Sr, Ti, Zn, and Zr. Anions that have relatively low hazards are:
flinnsci.com
FLINN METHOD
FLINN METHOD
#26b Waste for Drain Disposal Without Pretreatment
Bisulfite (HSO3¯) Borate (BO33–) Bromide (Br¯) Carbonates (CO32–) Chloride (Cl¯)
Cyanate (OCN¯) Hydroxide (OH¯) Iodide (I¯)
Oxide (O2¯)
Phosphate (PO43–) Sulfate (SO42–) Sulfite (SO32–) Thiocyanate (SCN¯)
This list of less hazardous cations and anions is presented only as a guideline. Your chemical judgment, volume of waste, and local regula- tions must also be considered. For example, sodium hydroxide contains an acceptable cation (Na) and anion (OH) but is in fact a toxic and corrosive material that should be treated before disposal.
Materials Required
Crumpled newspaper Cardboard boxes
Heavy tape to seal boxes
Procedure
Aqueous solutions containing nonhazardous wastes (as defined by the EPA) may be suitable for drain disposal if—and only if—the school drains are connected to a sanitary sewer system, with a water treatment plant operating on the effluent from your drains. These guidelines must be followed:
• Do not use this procedure if your drains empty into groundwater through a septic system—or into a storm sewer (see note below).
• These materials may generally be disposed of in quantities not to exceed 100 grams each day for each substance by rinsing them down the drain with a large excess of water.
• Do not put combinations of materials down the drain at one time. Local regulations may be more strict on drain disposal than the prac- tices we recommend. You must determine what is permitted in your area. Sewer disposal in your community is regulated by an ordinance of your local water treatment facility. The regulations will spell out in considerable detail the allowable limits for various waste components. Because each water treatment facility is unique, you must contact the facility and get a copy of the ordinance. We also recommend meeting with representatives of the local treatment facility if a major labora- tory cleanup and disposal is planned. A good working relationship with the treatment facility will make everyone more comfortable with the appropriate use of the sewer as a disposal method. For example, in some areas, compounds of aluminum, copper, and zinc are not permitted in sanitary sewers. In most cases, we recommend that you substitute Flinn Disposal Method #26a for this one. All the materials recommended for this procedure are water-soluble to the extent of at least 3%, and represent a very low toxicity hazard. In addition, the
organic materials are readily bio-degradable.
Note: If your drain system does not empty into a wastewater treat-
ment facility, do not put these substances down the drain. Rather, landfill the non-flammable substances and aqueous solutions accord- ing to Flinn Disposal Method #26a, and dispose of all others using a licensed hazardous waste disposal company according to Flinn Disposal Method #26c.
Bury solids in a landfill site approved for the disposal of chemical waste. Do not mix different materials by removing them from their separate containers as unpredictable chemical reactions may occur. Pack separate containers into sturdy cardboard boxes, separating containers from each other with crumpled newspapers to avoid inad- vertent breakage. Seal the cardboard boxes with heavy tape.
This procedure is recommended for a wide array of materials, from aspirin to zinc. We use the term “landfill site approved for the disposal of chemical waste” with the full realization that many of these substances can go into the school trash. However, regulations about landfill use change with great frequency. Local regulations should be consulted about exactly what you can and cannot place in the landfill in your area. You must determine what is permitted in your area. Do not assume that it is acceptable to dump materials into the school trash. Take the time to investigate. Some instructors have made this “investi- gation” a student project, and have learned a great deal in the process.
If you have made aqueous solutions of the water-soluble or alcohol- soluble materials classified for disposal under this procedure, we recommend that you dispose of these solutions according to Flinn Disposal Method #26b.
Please...Read the Narratives
Important narratives precede these specific chemical disposal methods! Please read each narrative carefully! Do not use these procedures if you are not comfortable with the chemistry. Do not use these procedures without first consulting with your local government regulatory officials. These procedures may not be used in some jurisdictions. All procedures involve some hazards and risks. Once again...read the narratives that precede these specific chemical disposal methods.