The most important chemicals used in the petroleum industry

Transcription

1 The most important chemicals used in the petroleum industry and the potential content of persistent pollutants in these Hege Nilsen, Statoil

2 Discharges to sea of chemicals from the Norwegian petroleum industry in The statistics include discharges from all fields with production facilities on the Norwegian continental shelf. Figures are collected from and are available on ("Emissions and Discharges from the Norwegian Petroleum Industry 2003 ).

3 3 Total amounts of chemicals 2003 The total consumption of chemicals was tonnes. Use, discharge and injection of chemicals from the Norwegian Petroleum Industry (tonnes) Discharges were tonnes. Total amount injected was tonnes The specific discharge per delivered unit of oil and gas was 0,49 kg/sm3 o.e Source: OLF Use Discharge Injection

4 Discharges of chemicals 2003 divided according to operational groups 4 Chemicals are used in a wide variety of applications, from drilling to production and transport. 0 % 1 % 7 % Discharges ( tonnes) 2 % 0 % 1 % 0 % Drilling and well chemicals account for approx tonnes (79 per cent) of total discharges. Production chemicals: 9 per cent Gas treatment chemicals: 7 per cent 9 % Drilling and well chemicals Production chemicals Injection chemicals Pipeline chemicals Gas treatment chemicals Utility chemicals Chemicals added to the export flow Chemicals from upstrem facilities Water trace components 80 %

5 5 Ecotoxicological testing and evaluation of chemicals The operator shall ensure that chemicals that are used or discharged have been tested with regard to eco-toxicological properties. The operator shall categorise, evaluate and choose the chemicals in relation to Appendix 2 to The Activities Regulations. The ecotoxicological testing includes testing of biodegradability, bioaccumulation potential and acute toxicity.

6 6 Ecotoxicological tests Biodegradability in seawater (all individual organic substances). Bioaccumulation potential (all individual organic substances): OECD 117 or 107 Partition Coefficient (n-octanol/water), or Bioconcentration factor (BCF) The following toxicity tests are required: 1) Skeletonema costatum 2) Acartia tonsa 3) Scophtalmus maximus or Sheepshead minnow 4) Corophium volutator; Required if the chemicals are absorbed to particles (Koc > 1000) and/or sink and end up in the sediments (for example surfactants).

7 7 Categorization of chemicals - Black category substances on the following lists: Prioritized substances in Table 8.1 of White Paper 25 ( ) Annex 2 of the OSPAR Strategy with regard to Hazardous Substances substances with the following ecotoxicological properties: biodegradability of BOD28 <20 % and bioaccumulation potential of log Pow >5. biodegradability of BOD28 <20 % and high acute toxicity (LC50 or EC50 < 10mg/l) classified as mutagenic or reprotoxic. endocrine disruptors such as alkyl phenols (incl. ethoxylates), bisphenol A, phtalates and organic tin compounds (incl. polymers of such substances and substances with similar properties). The same criteria apply to the biodegradation products.

8 8 Categorization of chemicals Red category substances with the following ecotoxicological properties: Inorganic substances which are acute toxic (EC50 or LC50 < 1 mg/l) Organic substances with a biodegradability of BOD28 < 20 % Substances that meet two of the three following criteria biodegradability BOD28 < 60 % bioaccumulation potential log Pow > 3 acute toxicity LC50 or EC50 < 10 mg/l In addition, substances on OSPAR Convention, appendix 2 and the OSPAR list of substances liable to cause taint shall be categorized as red if an expert evaluation indicates that discharges may cause harm to the marine environment.

9 Categorization of chemicals Yellow and Green category 9 Yellow category consists of substances that from the intrinsic properties of the substances shall not be defined as red or black, and that are not on the PLONOR list Green category consists of substances on the PLONOR list and are assumed not to pose a risk of significance. PLONOR list; OSPAR List of Substances/Preparations Used and Discharged Offshore which Are Considered to Pose Little or No Risk to the Environment (PLONOR),

10 10 Distribution of total chemicals in 2003 Green category includes the water content of chemicals Black substances are mainly dope and hydraulic oil Total: tonnes 8 % 0,5 % green yellow red black 0,004 % 92 %

11 Zero environmentally hazardous discharges to the sea by the end of Chemicals: Zero discharges of chemical additives in the black SFT category (by default forbidden to use and discharge) and the red SFT category (high priority for phasing out via substitution). Zero discharges or a minimisation of discharges that can lead to damage to the environment by substances in the yellow and green SFT categories From Report to the Storting No. 25 (2002/2003) The Government's Environmental Policy and the State of the Environment

12 12 Historical development Most of the operators have come a long way with respect to replacing Discharges (tonnes) today s environmentally hazardous chemicals with less hazardous alternatives (substitution). The oil and gas companies have made good progress in this area. The most important issues remaining are to find solutions for the environmentally hazardous substances in thread lubricants SFT, ( 0 Green Yellow 8.html).

13 13 Historical development Discharges of red substances (tonnes) 500 Discharges of black substances (tonnes)

14 14 Potential content of persistent pollutants Discharges of "persistent" additives Total: 331 tonnes 0,01 % 1 % 1 % List over prioritized chemicals included in target one on the priority list, Storting white paper no. 25 ( ) Biodegradability in sea water <20% and log Pow > 5 Biodegradability in sea water <20% and toxicity EC-50 or LC- 50 <= 10 mg/l 98 % Biodegradability in sea water <20%

15 15 Contaminants Total contaminants 2003 (9,1 tonnes) Contaminants (heavy metals) are primarily derived from weight 3,24 0,01 0,01 1,94 materials, i.e. barite. 0,01 3,09 0,81 Mercury Cadmium Lead Chromium Cobber Arsenic Other

16 16 Definition of persistence Ready biodegradability tests Stringent screening tests in which a high concentration of test substance (in the range of mg/l) is used, and the biodegradation rate is measured by non-specific parameters (DOC, BOD, CO2) Hazard classification: a chemical attaining a pass level >60% in the seawater test may be classified as readily biodegradable and it may be assumed that the substance will undergo rapid and ultimate degradation in the environment.

17 17 Definition of persistence Inherent biodegradability tests Tests that possess a high capacity for degradation to take place (prolonged exposure, low test substance to biomass ratio). Hazard classification: Biodegradation rate above 20% in the test may be regarded as evidence of inherent, primary biodegradabability. Biodegradation rate above 70% in the test may be regarded as evidence of inherent, ultimate biodegradabability. Not attaining this pass level leads to a preliminary conclusion of persistency in the environment. Evaluation of effects of degradation /transformation products

18 18 Definition of persistence Few offshore chemicals are tested for inherent biodegradability Less than 20% biodegradability in a ready biodegradability test (OECD 306) does not necessarily imply persistency! Persistent, but pollutant? With low biodegradability (<20%), no acute toxicity revealed and low bioaccumulation potential is the substance a pollutant? Precautionary principle! Eliminate any adverse effects we do not (yet) know.

19 Examples of offshore chemicals with <20% biodegradability in sea water tests 19 Scale inhibitors and dissolvers Polymers of polyacrylate, polyacrylamide and phosphonate Drilling chemicals Organophilic clay Emulsion breakers Block polymers Foam retardants Polydimethyl siloxan

20 20 Degradation products The Authorities has (July 04) suggested some changes to the The Activities Regulations, which include the following: For moderately biodegradable substances (biodegradation measured as BOD28 between 20& and 60%) in the yellow category the properties of degradation products shall be evaluated. Goals? Substitute substances that may be transformed into hazardous degradation products Make choices among chemicals which are made up of the same chemistry, but has reached different degradation products along the 20% border or the 60% border. Avoid the development of unclean products (an increased level of unreacted monomers will increase the degradation result of a polymer)