Rapidly biodegradably

Transcription

1 Rapidly biodegradably hydraulic oils An overview International Eco-labels Internationally approved norm ISO 15380

2 Rapidly biodegradable hydraulic oils 2 For more than 20 years various rapidly biodegradable hydraulic oils have been offered in the market. Only few products managed to gain a significant market acceptance. Undisputedly we were able to do this with the rapidly biodegradable PANOLIN hydraulic oils. The market share for PANOLIN products, applying to the use of biodegradable oils in mobile machines (Germany), is at almost 50%. This percentage concerns the forestry industry and has been confirmed by the KWF in the FTI (member s newsletter of the KWF), issue /2009. This brochure contains an overview over the norms and legal situation as well as advantages and disadvantages of various product groups. I Background Description, general and legal point of view Rapidly biodegradable oils are used mainly in environmentally sensitive areas. In stationary systems rapidly biodegradable hydraulic oils are used mainly due to legal requirements. The verdict of the District Court Hamburg no. 312 O 730/06 dated states the legal position as follows: it is to be observed that for the user of a machine deployed in environmentally sensitive areas, such as nature and water preservation areas, there could be risks of liability that may even threaten the company s existence in case of hydraulic oil leakage. Another verdict of the District Court Hamburg no. 312 O 795/05 dated describes the legal position as follows: «Users of machines in environmentally sensitive areas for insurance / liability reasons are furthermore obliged or even forced to only fill in oils and lubricants in their machines, which, if released to the environment, would result in the smallest possible damage to the environment.» II. Definition «rapidly biodegradable» Rapidly biodegradable hydraulic oils the emphasis in this case is on «rapidly» - are often identified with the simple description «bio oil» or biodegradable. As a test method for the biodegradability the test methods according to OECD 301x have established themselves internationally. These test methods are also mentioned in the current ISO 15380:2002 standard and are an essential basis for awarding the current Eco Labels such as e.g. Euro- Marguerite (R1, T3) or Blue Angel (RAL-UZ, since ). The test methods OECD 301(A to F) have been established for the determination of the rapid biodegradability according to VwVwS (Verwaltungsvorschrift wassergefährdender Stoffe Administrative Regulations for water endangering chemicals) since (incl. Amendment from 2005). In addition to that the CEC organisation itself confirms that CEC-L-33-A-93 is seen as technically out-dated: The task group for this test method has been terminated. According to this understanding this test method does not correspond with the current state of technology.

3 Rapidly biodegradable hydraulic oils 3 III. Valid standards The current internationally valid standard for the classification of rapidly biodegradable hydraulic fluids in the respective material groups is ISO (2004). The precursor of this standard was VDMA (1994). That is a technical rule which has never been conveyed to a standard, but is nonetheless widely cited. Nevertheless there is a certain conformity with the standard ISO A correct and clear reference to a standard for rapidly biodegradable hydraulic oils is generally possible with ISO There are numerous eco labels and it is sensible that the products used comply with the standard of the respective country / region. Based on their historical development eco labels require, amongst others, the rapid biodegradability. In addition some newer eco labels require a share of >50% of renewable resources. IV. Correct and complete identification of the biodegradability The simplified description «bio-oil» or «biodegradable» without a concrete reference (with percentage indication) of the used and approved OECD 301x test method in this context is incomplete. If ISO is indicated, this includes that the biodegradability has been tested according to OECD resp. ISO. Eco labels that require rapid biodegradability acc. to approved test methods and a share a renewable resources (some) >50%: Eco labels that require the rapid biodegradability acc. to the OECD 301 test methods: This overview does not claim to be complete and there are additional national requirements and eco labels, most of which also require rapid biodegradability acc. to OECD 301 test methods. Eco labels are often called for. So e.g. in machines used in forestry and want to get the KWF approval mark. Here it is necessary to prove that the pressure fluid in use has been awarded one of the approved eco labels ( BLAUER ENGEL (Blue Angel) or EURO-MARGERITE) To receive one of the above mentioned eco labels the biodegradability needs to be confirmed by test method approved by the respective procurement regulations. The Blue Angel (BLAUER ENGEL) and/or the EuroMargarite require the test method acc. to OECD regulations. The test method acc. to CEC-L-33-A-93 is not sufficient!

4 Rapidly biodegradable hydraulic oils 4 V. Water hazard classification WGK All fluids are being classified in three classes according to the VwVwS valid in Germany: WGK-1 low hazard to waters WGK-2 hazard to waters WGK-3 severe hazard to waters When using rapidly biodegradable hydraulic fluids in mobile machines the WGK at best has a secondary relevance. Primary in such applications it is the matter of biodegradability. When used in stationary plants in contrast the WGK has relevance. To classify the fluids into a certain WGK acc. to VwVwS, the regulations OECD 301 (A to F) are the specified test methods to determine rapid biodegradability. The test method CEC-L-33-A-93, however, is of no relevance here. The WGK classes are primarily valid in Germany, they are however understood in many countries, nevertheless they cannot be internationally translated just like that, even though there is a heavy overlap with the EU-Directive EC/1999/45 add. amendment EC/2006/8 in regards to limit values and test methods. VI. Technical Performance Level Machine and component manufacturers can define their own performance level. Therefore it is reasonable that the biodegradable hydraulic fluids have an application approval from the respective machine and component fabricants. Comprehensively the following tests / performance levels are approved: Wear protection test: FZG Test A/8.3/ load stage (DIN resp. ISO :2000) Vickers 35 VQ-25m V104 C Oxidation stability: ASTM D (Dry TOST) > h RPVOT according to ASTM D 2272 > 600 Min. (is rarely indicated resp. passed by only few and very high performance products) Technical minimum requirement: Defined in ISO resp. VDMA VII. Overview of biodegradable hydraulic oils with short description In the sector of the rapidly biodegradable hydraulic fluids according to ISO (VDMA 24568) there are 4 structured material product groups: 1. Vegetable oils, abbreviated to HETG (Hydraulic Oil Environmental TriGlyceride) Due to their very restricted temperature-stability as a result of their «double bond», HETGs did not become accepted, especially for technically demanding / sophisticated applications. Also disadvantageous is the natural fluctuation of the spreading of the molecular weight (Variety of the chain length of the carbon atoms) which differ seasonally and regionally. 2. Polyglycol oils, abbreviated to HEPG (Hydraulic Oil Environmental PolyGlycol) HEPG oils are very sophisticated products. In certain circumstances they are not compatible with a lot of paints as well as sealing materials and hoses and have been banned by some machine manufacturers in the meantime. Depending on the molecule type they are not, or are only partially oil-soluble. When the HEPG oils get into the environment (due to a leakage or an oil accident) the products containing ethylene oxide do not offer any advantages because they rapidly mix with water and will settle to the ground due to their higher specific density (not for PPGs). Numerous types are classified WGK 1. Today polyglycols can not accomplish the criteria of renewable resources for

5 Rapidly biodegradable hydraulic oils 5 obtaining ecolabels. Due to the above mentioned reasons, HEPG oils have only a small market share in the sector of the rapidly biodegradable hydraulic oils. 3. Synthetic Esters, abbreviated to HEES (Hydraulic Oil Environmental Ester Synthetic) In case of synthetic esters oils and within the same HEES-group the users have the choice between two groups: Unsaturated synthetic ester products mostly contain (similar to HETGs) vegetable resources. Because of the unsaturated composition they have only restricted thermal strain. The low temperature stability is lower and gets worse after longer service life. Some manufacturers of mobile machines advise against the utilisation of unsaturated ester products. Saturated synthetic ester products currently offer the most established positive application advantages for a longer period of time. From the material point of view saturated synthetic ester products have the advantage that they can be produced both from renewable resources and fossil resources. The mainly technical advantages can be found in the area of e.g.: high temperature and ageing stability long changing intervals improved cold start properties very good wear protection and good compatibility with sealing materials, paints and hoses 4. HEPR Oils (Hydraulic Oil Environmental Polyalphaolefine and Related Products) Most HEPR hydraulic fluids are very good products from a technical point of view. Depending on the formulation, however, the biodegradability may be borderline. Disputable in this regard could be those products that are based mainly on thin fluid PAOs (Polyalphaolefine). With those products the thickening to reach the desired viscosity (e.g. ISO 46) is done with high viscosity esters or VI-improvers. Viscosity-Index (VI) improvers are polymers with little shear stability, therefore after a longer period of use the viscosity might reduce. HEPR oils are usually classified in WGK1. PAO based hydraulic oils: In the market there are now also PAO based hydraulic oils that are advertised as biodegradable but are not to be classified to the HEPR group and/or do not comply with the norm ISO The lacking classification is an obvious disadvantage. Depending on the formulation other disadvantages can be added, such as e.g.: a. If they reached a high viscosity with a high percentage of VI-improvers, they are generally not sufficiently shear stable for a longer service life and are also volatile. b. Due to their composition they show a relative similarity to mineral oils and after an oil accident they will be detected as mineral oils (DIN H), as both material groups chemically are hydrocarbons. c. It is not possible to reliably determine the mineral oil content in a PAO based fluid with a regular oil analysis. d. In case of oil leakages in water PAO based oils, like mineral oils form an iridescent film. These points make clear that PAO based products often don t meet the expectations that a user usually has towards a rapidly biodegradable hydraulic oil. This concerns especially those products that do not achieve the minimum biodegradability acc. to OECD 301 methods and just show biodegradability acc. to the out-dated CEC-L-33-A- 93 test method. This tests the comparative biodegradability and not, as acc. to the test method OECD 301B, the determination of the ultimate biodegradability. The OECD 301B concerns the grade of decomposition in percent, that is achieved when the test substance is metabolized by micro-organisms into carbon dioxide, water, mineral salts and new micro-biological biomass. This differentiation is important because when in the CEC test method the comparative biodegradability is mentioned this does not say anything about whether a substance will be quickly and completely degraded in nature.

6 Rapidly biodegradable hydraulic oils 6 VIII. Miscibility with conventional and biodegradable hydraulic fluids with each other Generally the mixture of all rapidly biodegradable hydraulic fluids with each other as well as hydraulic fluids according to DIN is not allowed because of the different disposal codes. Foreign oil levels, especially mineral oil, may not exceed 2%. It is not possible to offer reassurances above this level as it does not conform with the relevant standards, and will not be accepted by machine and component manufacturers under the terms of their guarantee. Mostly it is stressed that a mixing will lead to the cancellation of any guarantee claims. Generous «miscibility approvals» are generally formulated by the oil suppliers themselves, are therefore commercially motivated but usually without any technically traceable basis. IX. Compatibility with sealing materials and hoses Even after more than 25 years of practical experiences there (unfortunately) is no simple and generally valid statement for this point. The reason for this is the fact that the hydraulic fluids as well as the different elastomers are chemical mixtures. The past 25 years however have influenced their development mutually. From today s point of view it can be confirmed that most of the conventional sealing materials and hose materials are compatible with most of the synthetic ester oils used. At the moment the manufacturers of sealing materials refer to the nowadays numerously available products that are well compatible with synthetic esters for a long period of use. The same is being stressed by the manufacturers of hoses. However, all general statements are still dangerous because there are neither only good nor only bad sealing materials, nor only good nor only bad fluids. The differentiation already starts with differently formulated mineral oils and continues with synthetic and rapidly biodegradable fluids. Categorical statements that which do not consider this variation can be considered as too highly sales motivated, and can therefore represent an incalculable risk for the user. In most cases hoses that fail prematurely due to pin hole formation, have a weakness due to production or manufacturing. The cause for the failure is not the use of a certain oil type, only the point in time at which the failure occurs could possibly be linked to that. In seldom cases such a cause of failure can be linked to the use of a certain oil type. Failures due to pin hole formation have been known for a longer time than rapidly biodegradable oils. HETG and HEPG products are seldom used; that is why in this case an individual compatibility check is advisable. For the HEPR products it strongly depends on the specific formulation. If they contain esters as viscosity improvers, it has to be assumed that the characteristics of the esters will also be found in HEPR products. Otherwise it is advisable to note that several sealing materials swell slightly when in contact with PAO oils, whilst a lot of sealing materials actually shrink.

7 Rapidly biodegradable hydraulic oils 7 X. Summary Since the beginning of their development more than 25 years ago rapidly biodegradable hydraulic oils have extended their marked share on national and international level. In many cases they have become indispensable from an environmental view point, whilst at the same time economic aspects have been brought into focus. Saturated esters in particular have proven to be suitable for long-term use and do not introduce extra cost over the life of the product. The thought of the environmental protection is irreversibly and constitutionally positioned. The requirements (details) are regulated in national and European Chemical and Environmental Law. Rapidly biodegradable hydraulic oils are an integral part of the sustained environmental thought and efficiently contribute to the environmental protection. The petroleum resources which are becoming more and more scarce and more and more expensive give a further economic entitlement to the increased use of lubricants from alternative resources. So for the future a further important advantage of the synthetic ester products is their material flexibility. Today these can be produced from petrochemical and renewable resources. This aspect will become more and more important. The best chances for the future are with those products that have a considerable long-term suitability. More and more the change intervals of hydraulic oils are extended. In the ideal case the hydraulic oil does not need to be changed during the entire useful life of the machine. Due to enhancements in the oil maintenance, e.g. Microfiltration in the by-pass, on-board oil analysis using suitable sensor technology and laboratory analyses, it is already today possible to achieve and secure life-time fill in numerous machines. Rapidly biodegradable hydraulic oils from the PANOLIN product range: HEES: PANOLIN HLP SYNTH, fully synthetic high performance hydraulic fluid on basis of saturated synthetic ester. Practically tested since more than 25 years. PANOLIN HLP SYNTH E, fully synthetic high performance hydraulic fluid on basis of saturated synthetic ester with 50% share of renewable resources. On the market with very good practical results since 2000 (formerly PANOLIN GRO SYNTH). HEPR: PANOLIN HEPR SYNTH, biodegradable high performance hydraulic fluid on basis of synthetic hydrocarbons.

8 Author: Mr. Milorad Krstić Chairman of the KLEENOIL PANOLIN AG For the professional revision, corrections and amendments of this brochure I would like to thank: Dr. Mathias Woydt BAM Bundesanstalt für Materialforschung und -prüfung Dr. Heinrich Theissen IFAS RWTH Aachen Dr. Gabriele Peterek Fachagentur Nachwachsende Rohstoffe e.v. (FNR) Mr. Patrick Lämmle PANOLIN AG August 2010 / All rights reserved. Reprint even in parts is not allowed. No part of this brochure may be reproduced or edited, duplicated or processed by using electronic systems without written consent of the KLEENOIL PANOLIN AG, Dogern. KLEENOIL PANOLIN AG / st / Englisch KLEENOIL PANOLIN AG D Dogern Telefon Telefax