Disposal of hazardous liquids

Hazardous liquids should be collected in colourless five litre plastic containers and handed over to the “Sonderabfallsammelstelle” (hazardous waste collection point).

Please remember that the plastic containers may only be used for five years after their manufacturing date!

Please note the following when filling your containers:

• Whatever the container you’re using, it must not be filled beyond 90% capacity.
• The containers must be sealed shut and clean.
• At the “Sonderabfallsammelstelle” (hazardous waste collection point), we do not accept overfull, damaged, leaky or contaminated containers.
• Solvent mixtures must be monophasic.
• Hazardous liquid waste must not contain any solid objects (e.g. pipettes, filter paper, sediments etc.).

Solvents containing halogens, halogen-free solvents as well as solvent mixtures must be collected separately. For financial reasons, please make sure to comply with this regulation. Prior to filling your canister with used solvents, please check whether you are using a container that is labelled correctly for your kind of solvent waste. A canister for halogen-free solvents that is contaminated with solvents containing halogens is twice as expensive to dispose of!

Halogen-free solvent mixtures

The most common halogen-free solvent mixtures can be classified as follows:

• aliphatic and aromatic hydrocarbons
• alcohols
• esters
• ethers
• ketones

^{*) Please laminate the appropriate labels and attach them to the handle of the canister. Working groups that do not have access to a laminator can get the appropriate labels from the “Sonderabfallsammelstelle” (hazardous materials collection point).}

Solvent mixtures containing halogens

Solvent mixtures containing halogens must be collected separately from halogen-free solvents.

The most common solvents containing halogen are dichloromethane (methylene chloride) and trichloromethane (chloroform).

According to the Verordnung zum Verbot von bestimmten die Ozonschicht abbauenden Halogenkohlenwasserstoffen (CFC/Halon Prohibition Ordinance), carbon tetrachloride must not be used as a solvent any longer.

You should therefore refrain from using chlorinated hydrocarbons for cleaning and degreasing purposes as much as possible.

^{*) Please laminate the appropriate labels and attach them to the handle of the canister. Working groups that do not have access to a laminator can get the appropriate labels from the “Sonderabfallsammelstelle” (hazardous materials collection point).}

Acids

Aqueous solutions with a pH-value under 7 should be disposed of as acids. Acid mixtures should be handed in to the “Sonderabfallsammelstelle” (hazardous waste collection point) in five litre canisters.

• The canisters must be free from oil, grease and organic solvents.
• You must not mix acids that react with each other.
• Organic acids must be collected separately from anorganic acids and solvents.
• Please make sure to include the pH-value on your documentation.

The following acids must be collected separately from other acids:

• nitric acid
• chromic sulfuric acids (due to its high risk potential, chromic sulfuric acids should not be used for cleaning purposes)
• fluoric acid (please indicate the concentration)

Solutions

Aqueous solutions with a pH-value above 7 should be disposed of as base solutions. Mixed solutions can be handed over to the “Sonderabfallsammelstelle” (hazardous waste collection point) in five litre canisters.

• The canisters must be free from oil, grease and organic solvents.
• You must not mix solutions that react with each other.
• Please ensure to include the pH-value on your documentation.

Aqueous solutions containing heavy metals

When disposing of aqueous solutions containing heavy metals, you must first precipitate and filter out any heavy metals. The resulting dry waste may be disposed of with other absorbing matter.

Other aqueous laboratory waste

You may only dispose of aqueous laboratory waste via waste water if you comply with the Satzung der Stadt Konstanz über die öffentliche Abwasserbeseitigung (Abwassersatzung, AbwS) (city of Konstanz regulations on public waster water disposal).

In this context, the following rules and regulations apply:

• §8 AbwS (Verbot des Einleitens, Einleitungsbedingungen)
• Attachment on §8 para. 2 no. 9 AbwS (Grenzwerte - boundary limits)
• If you exceed the limits specified in the attachment, you must dispose of your aqueous waste via the “Sonderabfallsammelstelle” (hazardous waste collection point).

Photographic chemicals (for developing and fixing)

Photographic chemicals for developing and fixing contain substances that are hazardous to water quality. You must collect them separately and hand them over to the “Sonderabfallsammelstelle” (hazardous waste collection point) as hazardous waste.

Waste oils and grinding emulsions

Do you need to dispose of waste oils?

Keep the original oil containers; these are the most suitable for return as they already have the correct labels.

If you do not have the original containers, please email gudrun.vonscheven@uni-konstanz.de oder a.keller@uni-konstanz.de.

Used oils are used half-liquid or liquid substances that are made from mineral oil or synthetic oil either wholly or in part, including oily residues from containers, emulsions and oil and water mixtures.

We differentiate between used oils that are eligible for recycling and used oils that must be disposed of as hazardous waste. Recyclable used oils must not be mixed with other used oils or hazardous waste.

Used oils eligible for recycling include:

• oilbath oils
• combustion engine and gearbox oils
• mineral engine, turbine and hydraulics oils, as long as they contain less than 20 mg of PCP/kg or less than 2 g of overall halogens/kg

^{*) 200-litre barrels: please attach one label each to the top and side}