The invention relates to a method for dosing additives from recyclable disposable containers which are connected to pump- ing accessories of petrol stations, as well as an accessory for the purpose.

The object is to reduce the establishing and maintenance costs of the oil companies for the need of a so-called"com- plete service station"for storage capacity from five to three tank units, with the consequently reduced capital bind- ing for the local station unit which buys and owns the petrol and diesel oil stock which at all times is present in the tank reservoirs dug in.

Further, the method allows use of additives which to day are available, but not in use, or which, otherwise, could have been developed by the oil companies and used in their own marketing.

The object is also to deliver as correct mixtures as they pretend to be.

All additives are more or less injurious to health and in- flammable, and the method is based on a closed system, wherein attendants or customers do not come into contact with vapours therefrom or are subjected to inhalation of such va- pours.

The individual oil companies own and has the maintenance re- sponsibility for the petrol and diesel tanks and pumps in- cluding electronics to and incorporating the cash register terminals, as well as roof superstructure for signposting. A tenancy agreement is established with the individual opera- tional unit, typically for ten years, and a monthly rent is paid for this accessory.

The station owner of the operational unit buys petrol and diesel and pays in cash. Moreover, he owns house, site and kiosk goods of any kind as well as workshop accessories and other moveables.

To day, from the pumping accessories of a"full service sta- tion", a customer is offered the following: -With a special push button, 95,97 or 98 octane lead free petrol is chosen. 97 octane mixture is provided in that the pumping accessory sucks 40% amount of fluid from res- ervoir I with 95 octane which is mixed in a pumping pistol with 60% amount of fluid from reservoir II with 98 octane.

-With a special push button one will also receive 97 and 98 octane petrol with lead substitute. Reservoir III contains 98 octane petrol with lead substitute. In order to get 97 octane petrol with lead substitute, 60% of the amount of fluid from reservoir III is automatically mixed with 40% of the amount of fluid from reservoir I, which contains 95 octane petrol, but without lead substitute. The result is that a customer buying 97 octane with lead substitute does

not get the goods he thinks, but instead a petrol contain- ing only 60% of the lead substitute it should have con- tained.

-With a special pump a customer may get clear diesel sub- ject to fee, from a reservoir IV. Diesel is admixed sub- stantial and up to 40% amounts of paraffin in districts having low temperatures in order to avoid that it converts into gelatinous consistence. The self-lubricating proper- ties of diesel oil is then reduced considerable, without the possibility for the oil companies to compensate there- fore e. g. by the admixture of universal two-stroke oil, which is admixable and which should have been done.

-From a further pump, one may get coloured diesel free of fee for tractors, boats, etc. from reservoir V, also with temperature variable paraffin addition, where it is up to the station unit to look after that fee-obliged user does not provide himself with diesel free of fee from an erro- neous pump.

The programmable software of the cash terminals contains the price elements which are valid at any time for the fuel types concerned which are chosen, based on fluid amount controls.

The amount of the fluid lead substitute added is small.

A German product which can be used is sold on 250 ml plastic bottles assigned a dosing cup; such a bottle being sufficient for 250 litres petrol, thus representing admixture of 0,1%.

A station selling e. g. 10,000 litres 98 octane with lead sub- stitute per week has, thus, a need for 10 litres lead substi- tute only.

The same amounts of additive of the type catalyst cleaner is used, which is not available in the selection of goods of the Norwegian petrol stations.

Purchase, digging in and installation for a station which has to replace its five reservoir tanks after these have been used for years, amount to millions, and many oil companies therefore are reluctant to undertake such capital cost in order to maintain stations located in the districts, also because the customers also here require a so-called full service station having the five tank and pump units neces- sary. When only one operational unit is continued as full service station having only three tank reservoirs, investment and maintenance costs are reduced by 40%.

For an operational unit, the filling of e. g. three 15,000 litres petrol tanks costs NOK 413,000.- and two 20,000 litres diesel tanks NOK 233,000.-, or in all NOK 646,000.- Calculated on a theoretical average of one half tank filling, this represents a capital binding of NOK 323,000.- Eliminating a reservoir tank for 98 octane petrol with lead substitute and a reservoir tank with coloured diesel, the average capital binding will be reduced by NOK 110,000.- or 34%.

From the patent literature is known: -US 5,163,586 which describes a measuring and mixing system for admixtures to petrol, where the admixtures are filled into storage tanks and coupled to pressure and measuring units connected to the distribution system's upstream fluid meter, so that up to two additives can be delivered in correct amounts to a flow of petrol from two sources.

-The patent discloses admixtures for improving octane (anti-knock)-quality, removal of carbon depositions from combustion chambers and fuel injectors, reduction of dis- charge upon admixture of oxygen-liberating admixtures (oxygenates).

-When the amounts of admixture are very small, such as one cm3 or a millilitre per gallon, the admixing rate will be 0,026%.

-The accuracy requirements of American trading standards service will, due to control considerations, not allow less admixing rates than 0,4%, if payment for the sub- stance admixed is effected.

Therefore, the invention is defined to relate to admixture of additions generally having a somewhat larger volume in rela- tion to the fuel volume (This invention applies to any and all fuel additives, and to fuel components which are gener- ally of larger volume ratios to the fuel volume.) E. g. oxygen-liberating additions amount to volumes of several per- cent.

The method in accordance with the invention aims at dosed supply of additives from recyclable disposable containers connected to pumping accessories of petrol stations, in that these normally liquid admixtures are supplied to the amounts of fuel in very small amounts during tapping performed by customers, e. g. 0,1% liquid lead substitute and liquid cata- lyst cleaning agent, 0,5% liquid diesel colouring matter in fuel sold duty-free, and up to 2% addition of universal two- stroke oil to frost-resistant diesel oil admixed up to 40% paraffin.

Admixture is not assumed to take place continuously, but through batch dosages, so that e. g. lead substitute and cata-

lyst cleaning agent are added in one dose of one ml for each tenth litres of petrol tapped to customer.

Diesel colouring matter is e. g. added in doses of 2,5 ml for each fifth litre filled, while e. g. five ml universal two-stroke oil is supplied in doses to each litre paraffin- diluted diesel filled.

Disposable containers are sold and delivered e. g. by the oil companies or by a special firm delivering to all chains of petrol marks, following already existing distribution chan- nels for such products.

Disposable containers could contain from 10 to 20 litres liquid, having standard spout aperture, which is formed such that when a container is turned upside down, it can be screwed to sealingly cooperation with a corresponding, threaded spout holder attached directly on the petrol and diesel pumps, possibly integrated into newer produced acces- sory. When screwing has been carried out, it is opened for liquid flow out of container through the spout holder arrangement to the programmable dosing accessory. Indicator on the disposable container shows the liquid level therein at any time.

Between the spout holder and the dosing mechanism firmly mounted to pump accessory exists an additive-carrying cavity in the form of a container and necessary pipe connections, securing coverage of a continuous need for amounts of addi- tives of some hours or one day, so that replacement of con- tainer with a new one can take place e. g. upon routine in- spection of the liquid level of the containers one time each day.

The firmly mounted spout holder's container can be utilized for premixing additives, in that first a given amount of pet-

rol is filled prior to the attachment of a disposable con- tainer having a given amount of additive, e. g. in the propor- tion 1: 1 or 1: 10. To the fuel, the double or ten times, re- spectively, of the mixed additive must then be dosed; reduc- ing the requirements to dosing accuracy, enabling a more cor- rect dosage with a simpler dosing mechanism and improving the possibilities for control by the Trading Standards Service.

To a diesel pump is coupled both a container for colour addi- tion and a larger container for the addition of two-stroke oil, and the diesel pump is equipped with an insertion slot for a polet or magnetic plastic card for tractor and boat owners, who are legitimate users of duty-free diesel. The control function is then facilitated for the station owners.