REMOVERS OF PETROLEUM PRODUCTS ALSO CALLED: DISPERSANTS, WETTING AGENTS, NEUTRALIZERS, SURFACTANTS AND DETERGENTS…
“Neutralizer” is the most inadequate term, because agents that could neutralize mineral oil derivatives simply do not exist.
When choosing a remover, one ought to consider the following three aspects of safety:
- for the user himself,
- for the surface and devices to be cleaned,
- for the surface and devices to be cleaned,
In the Polish market there appear ever new products designed for surface degreasing, which are by all means cheap and act radically on the surface being cleaned, but do not meet the above criteria. Usually, the person deciding about the purchase is not the direct user (which is a pity), and in most cases, the price is the most important criterion for purchase. Last year, a person who organized one of the tenders for removers argued with us that our prices were too high, and that we could have added some water and lower the price. And so, side by side with neutral, verified and tested products, the market still features products that are:
- corrosive, containing strong acids or bases,
- flammable, containing organic solvents (e.g. toluene),
- containing large amounts of phosphates and nitrates.
The use of all products has to comply with regulations on environmental protection (Environmental Protection Law, Water Law, Waste Materials Act), health and safety at work and fire protection.
Desirable features of degreasers for removing oil and hydrocarbon spills
- Non-flammable
Organic solvents content increases unwanted fire hazard.
- Preparations on water basis not containing organic solvents
Preparations containing organic solvents, beside their fire hazards, are also dangerous to human health – they can have carcinogenic, mutagenic and narcotic effects. In addition, they
introduce dangerous substances into the environment.
Such preparations, if delivered in the form of concentrate, may cause danger to workers during dilution. The presence of solvent may disturb the proper operation of separators or sedimentation basins. Consequently, behind the separator, instead of sewage clarified from petroleum products, we will have the preparation itself and oil waste which should have been captured in the device. This means that despite adequate and expensive protection (separator), the environment will be still contaminated.
Degreasers used on water surfaces (not always in accordance with international conventions or Polish regulations) should not contain substances listed on the Dangerous Substances
List, especially glycol derivatives. They only wash out lighter fractions from the petroleum spills. The remaining heavy fractions sink to the bottom of the reservoir and become a cause of unpardonable contamination which is very hard to remove.
- Neutral – the pH should be close to 7
pH = 7 means that the preparation is neutral and does not pose a threat to users and customers, does not affect installations and building materials and does not change the pH of the environment. Acidic solutions (pH from 1 to 5) may damage surface material (paving stone, concrete) and its finish (e.g. kerb stones). If handled improperly, such solutions may be hazardous to the health of users (skin injuries and other). Alkaline solutions may damage lacquered or aluminium parts of devices. Even with initial tests during the first cleaning, no one can guarantee that using such corrosive preparations will not damage the surface after a few months. Such solutions, if handled improperly, may pose a threat to the health of users (skin injuries; accidental contact of corrosive removers with the skin results in badly healing burns and contact with eyes may even cause blindness).
One ought to remember that pH is not the only sufficient criterion of product safety. We know solvents with a neutral pH, and there is an agent used on a massive scale in Poland which has a pH of 7 and contains almost 30% of a very dangerous substance – ranked first on the list compiled by the US Environmental Protection Agency.
- Cannot form a stable emulsion with hydrocarbons (oils and fuels)
Most sewage (except communal sewage) generated in factories, fuel bases, loading platforms, petrol stations and on highways, is initially purified in oil separators (or sedimentation basins). The separator utilizes the insolubility of petro-leum hydrocarbons in water and the fact that they remain on water surface. This task can only be performed if oil forms an unstable emulsion with water which separates after sedimentation.
Stable emulsion will not separate, it will flow through the separator (or sedimentation basin) and will release the whole load of hydrocarbons in the receiver. This receiver can be a sewage treatment plant in which large amounts of hydrocarbons will disturb the process of purification. This can be also a ditch or a stream, in which case the unseparated hydrocarbons will pollute the environment.
- Ready-to-use products (i.e. products with working concentration)
Ready-to-use products are safe and economic in use. Concentrates are often used without diluting, if we are in a hurry. Such way of handling creates hazards for the user and for surfaces or devices to be cleaned (in respect of too intensive action of the concentrate). Concentrates intended for dilution are used up much faster. Usually, just in case, we prepare more working solution than we actually need. The excess usually goes to waste.
Concentrates are also a threat to the environment. If used in undiluted form or improperly diluted, they unnecessarily load the environment with undue amount of foreign substances which have to decompose. It may lead to a local overload of the ecosystem and in consequence to reduction or complete inhibition of biodegradation processes. The permissible amount of surfactants which can be present in sewage is defined by regulations on environmental protection. Exceeding the permissible amount is subject to penalty. Bidders will often specify the dilution rate in terms of proportion and do not exactly inform which level of dilution is suitable for degreasing individual surfaces or elements to be cleaned. The user is then disappointed with the effectiveness of a cleaning agent and he is right. Stating the proportions as higher than 1:50 is foul play with regard to competitors’ products. A couple of years ago our regular buyer of ready-to-use products phoned in to complain that he had received an offer for a concentrate (dilution proportion – 1 l of concentrate : 100 l
of water), which meant that the new product was almost one hundred times cheaper than the one he was currently using at his fuel base. We suggested that he dilute it in the suggested proportion and perform the test of washing and degreasing the surface. Next day we received his order for our ready-touse preparation. The concentrate seller, faced with poor effectiveness, resorted to claims that distilled water should have been used for dilution, and the whole place was very dirty anyway. The only response he got was laughter. There have been many similar cases, and that is why in our training courses we always emphasize that paper can take anything – one ought to check and test. And one additional remark: the hardness of water used for dilution is a very important factor.
- Removers should not contain nutrients for the environmental micro flora (usually nitrogen and phosphorus compounds)
Some bidders state that their preparations, thanks to their nutrient content, facilitate and accelerate the biodegradation of oil derivatives in the environment. This is a typical halftruth and wishful thinking. In fact, in optimum conditions, in temperatures exceeding 19-20’C with good humidity of soil and good aeration, the supplement of nutrients stimulates the grow of soil bacteria decomposing hydrocarbons. Such conditions can be only created in laboratory or in special site installations. Oil derivatives which have been washed away and together with sewage were moved to a ditch or another receiver (e.g. soil) do not encounter favourable conditions for decomposition there. They will remain unchanged in the environment
and some of them – better soluble in water – will move together with rainfalls to underground water layers and will remain there forever. These water-soluble compounds are often carcinogenic and may pose a health threat to the entire population, if a drinking water intake is built on such a geological layer. Sewage-containing nutrients drawn into inland waters increase adverse phenomena of overfertilization of waters. This overfertilization may result in eutrophication, or gradual disappearance of life in these waters.
- The ability of bed penetration
Ability of bed penetration is a very important aspect. Penetration of products into the bed being cleaned ensures that deeper layers of porous surfaces will also be cleaned, i.e. concrete, paving bricks, etc.
How to acquire reliable information on removers offered on the market?
Vital information on chemical composition and hazards to the user and the environment is included in Material Safety Data Sheets of the product (Regulation of the Minister of Health, dated December 14, 2004 – J.L. No. 2, item 7 and 8). The distributor is obliged to make the MSDS available to the buyer. MSDS should contain information on chemical composition (section 2). The individual chemical components are named and labelled with CAS numbers. If the number is known, one can identify a given substance and the hazards connected with its use in the “List of Dangerous Substances together with their classification and marking” – Appendix to the Regulation of the Minister of Health, dated July 3, 2002 (J.L. No. 129 Item 1110 of August 14, 2002).
In addition, MSDS should include the following important data:
- Identification of substance/preparation,
- Composition and information about components,
- Identification of hazards,
- First aid,
- Fire fighting measures,
- Accidental release measures,
- Handling of the substance / preparation and storage,
- Exposure controls and personal protection,
- Physical and chemical properties,
- Stability and reactivity,
- Toxicological information,
- Ecological information,
- Disposal considerations,
- Transport information,
- Information about law regulations,
- Other information.
Znany jest nam przypadek, że ten sam produkt posiadał trzy różne karty charakterystyki producenta, głównego oferenta i pośrednika i na każdej z nich było inne pH. Do przetargu zostało podane pH neutralne.
There has been a case when one and the same product had three different MSDS, issued by the manufacturer, main bidder and agent, respectively, and each sheet claimed a different pH value. The bidding offer featured a neutral pH.
In case of any doubts concerning preparations, we should consult the Inspector of Dangerous Substances and Preparations, according to the Act of January 11, 2001 on substances and chemical preparations (J.L. No. 11, Item 84 as amended).
According to the above mentioned Act:
- professional use of dangerous substances and preparations without the MSDS is forbidden,
- persons using dangerous substances or preparations are obliged to read the relevant MSDS,
- persons using dangerous substances or preparations, who know on the basis of the information given (MSDS) that such substances or preparations may pose a threat to human health or the environment, are obliged to take action in order to prevent the occurrence of such a threat.
When using any type of preparation, we must understand that after cleaning the surface, the preparation will reach the environment sooner or later. Repeated use of an improper remover will contaminate the soil and water to a much greater extent than oil derivatives themselves.
One also has to remember that even if the preparation itself is safe and does not threaten the environment, the washings after degreasing oil derivative contamination constitute dangerous waste material and should be neutralized in accordance with the Act on Waste Materials.
Summary:
Because of their exceptionally radical action and budget price, when using the above mentioned products, we should always observe the instructions of use, the information in the MSDS and the legal requirements concerning environmental protection. This always entails additional expenses concerning e.g.:
- employment of intermediate reservoirs for pre-treating slops prior to their disposal to the sewage treatment plant,
- purchase of neutralizers of corrosive substances,
- providing workers with gloves, protective shoes and half masks,
- ensuring neutralization of dangerous remover waste in accordance with the regulations.
Usage of dangerous concentrates according to the instructions depends mainly on the sense of responsibility, scrupulousness and prudence of the employee. Based on our experience, we know that such virtues are rarely met, especially if the situation requires fast and firm action. In such cases, only the user is responsible for damage resulting from the improper use of preparation; the manufacturer does not bear the blame.That is why we should use preparations that are safe for the user, devices, installations and for the environment, that is to say:
- neutral,
- without flammable components,
- without nutrients for environmental micro flora,
- not requiring dilution,
- forming only unstable emulsions with oil derivatives,
- having good bed penetration capability,
- having references from experienced users.