Solvent consumption

WHAT YOU NEED TO KNOW BEFORE STARTING THE CALCULATION

An organic solvent is any volatile organic compound used for the following purposes:

• alone or in combination with other agents and without undergoing chemical change, for dissolution of raw materials, products or waste materials;
• as a cleaning agent to remove impurities;
• as a solvent; 
• as a dispersing agent; 
• as a viscosity adjuster; 
• as a surfactant (to adjust surface tension); 
• as a plasticizer (softner); 
• as a preservative. 

Organic solvents also encompass mixtures, either heterogenous or homogenous (solutions), comprised of two or more substances.

Solvent consumption is a value that determines whether an installation is subject to the obligations from the Regulation on volatile organic compounds (VOC Regulation), and if so, which requirements they have to comply with.

Input is the amount of organic solvents, including their amounts comprised in mixtures, which is used in performing activities, including solvents recovered in the installation and externally; all quantities count, each time they are used for the performance of the activity.  

Consumption is the total input of organic solvents into an installation during a calendar year, decreased by the quantity of organic solvents recovered and reused. It can be calculated using the procedure from Annex 4 of the Regulation.

HOW DO I CALCULATE SOLVENT CONSUMPTION?

Solvent consumption is calculated in line with the methodology defined in Article 6 and Annex 4 of the Regulation:

Solvent consumption SC = I1 – O₈

I₁ = Quantity of pure organic solvents, and/or their quantity in mixtures purchased, used as an input into each individual activity during one year.

Input I₁ is calculated in the following way.

I₁ = (I_1P + I_1S) – I_1K

Wherein:

• I_1P = Total quantity of organic solvents in stock at the beginning of the period for which the annual mass balance is being elaborated (e.g., quantities in stock on 31 December 2020)
• I_1S = Total quantity of organic solvents used during the year for the performance of each individual activity – real consumption during the observed year
• I_1K = Total quantity of organic solvents in stock at the end of the period for which the assessment is being performed (e.g., quantities in stock on 31 December 2021)

O₈ represents the quantities of organic solvents, including their quantities comprised in mixtures, collected for reuse, but not as an input into the observed process (not as the raw material in the same process).

Note: O8 generally represents the solvent that the operator internally collects for reuse, for example, distilled solvent, that the operator did not use during that year and is just storing it during this period. Collected quantities of O8 also do not encompass the quantities of organic solvents, including their content in mixtures, that the operator has collected for sale, or that are intended to be sold as commercial products.

HOW TO DETERMINE IF I AM SUBJECT TO THE REGULATION?

The obligations set by the Regulation apply only to companies that operate one or more activity listed in Annex 1, whose yearly solvent consumption exceeds the thresholds set by Annex 2 of the VOC Regulation.

If your company operates one or more of these activities, you should calculate your yearly solvent consumption based on the data of the previous year and compare it with the correspondent threshold.

If you exceed the threshold, it means that you are subject to VOC Regulation; the obligations for VOC operators and the explanation of how to fulfil them can be found at the website, in the section pertaining to About VOCs/Operator obligations.

CLASSIFICATION OF VOC OPERATORS ACCORDING TO THE ANNUAL SOLVENT CONSUMPTION

Depending on the total annual solvent consumption, installations where certain activities are performed, in line with Annex 2 of the Regulation, are classified as either small or medium. Depending on the classification, appropriate emission limit values are prescribed in Annexes 5 and 6 of the Regulation, which the operators must comply with. 

Installation classification in line with Annex 2 of the Regulation