Method for removing free fatty acids and water from the oils and fats used to produce biodiesel and from the crude esters produced during biodiesel production

Abstract

The invention relates to a method for removing free fatty acids and optionally water from the oils and fats used for the production of biodiesel and from the crude esters produced during the production of biodiesel by extracting the free fatty acids with a mixture of basic organic nitrogen compounds and water as an extraction agent.

Description

[0001] The present invention relates to a method for removing free fatty acids and water from the oils and fats used for the production of biodiesel and from the crude esters produced during the production of biodiesel by extraction.

[0002] Biodiesel is produced through a chemical process known as transesterification. In this process, oils or fats are converted into fatty acid esters, which are then used as biodiesel. Raw materials for biodiesel include vegetable oils such as rapeseed, soybean, and palm oil, or animal fats such as tallow and fish oil. Used cooking oils, such as frying oil, can also be used.

[0003] The main components of fats and oils are the triesters of glycerides and fatty acids, the so-called triglycerides. The physical properties of fats and oils are determined by a) the chain length of the fatty acids, b) the degree of saturation of the fatty acids, and c) the distribution of the different fatty acids across the three hydroxyl groups of glycerol. Fats with a high proportion of saturated fatty acids are generally solid at ambient temperature. Fats and oils consisting predominantly of unsaturated fatty acids are liquid at ambient temperature.

[0004] In the production of fatty acid esters as biodiesel, the content of free fatty acids (FFA) is crucial, as these interfere with the raw material because they react with the alkaline catalyst of the classical process described by Van Gerpen and Knothe (Jon Van Gerpen, Gerhard Knothe: Basics of the Transesterification Reaction in: Gerhard Knothe, Jon Van Gerpen, Jürgen Krahl: The Biodiesel Handbook, pp. 26-41, AOCS Press, 2005) to form soaps that hinder or prevent the separation of the glycerol produced in this process, thereby inactivating the catalyst required for transesterification.

[0005] In biodiesel plants operating according to this alkali-catalyzed process, the separation of free fatty acids from the raw materials is usually carried out by stirring with the alkaline glycerol phase produced in the process according to Türck's method as per EP 1 183 225 B1 and, after acidification of the loaded glycerol phase, is recovered from it by chemical cleavage of the separated soaps.

[0006] In plants operating solely on the acid-catalyzed process, particularly the Ingendoh process according to EP 2 464 715 B1, this approach cannot be pursued, as this process does not produce an alkaline glycerol phase. For this reason, biodiesel plants operating exclusively on the Ingendoh process are not currently feasible. In contrast to the alkaline-catalyzed process, deacidification of the raw materials is also typically unnecessary in this process, as transesterification functions smoothly with up to 80 wt% FFA in the raw material.

[0007] However, this process yields a crude product or crude ester that typically contains approximately 2-4 wt% FFA, which must be separated to meet the requirements for biodiesel according to DIN EN 14 214 in the final product.

[0008] Based on this, the invention aims to provide an improved process for removing free fatty acids and water from the oils and fats used to produce biodiesel and from the crude esters produced during biodiesel production, in order to improve the biodiesel manufacturing process, to open up new raw material sources and, in particular, to make the acid-catalyzed Ingendoh process available as a stand-alone process, even if no alkaline glycerol phase, such as that from the classic alkaline-catalyzed transesterification process, is available.

[0009] This problem is solved by the features of claim 1. Further developments and advantageous embodiments of the invention are set out in the dependent claims.

[0010] The inventive process for removing free fatty acids and optionally water from the oils and fats used for the production of biodiesel and from the crude esters produced during the production of biodiesel is carried out by extracting the free fatty acids with a mixture of basic organic nitrogen compounds and water as an extraction agent, wherein • the extraction is carried out at a temperature below the boiling point of the organic nitrogen compounds, • the proportion of basic organic nitrogen compounds in the extraction solvent is at least 20 wt.% and at most 60 wt.%, preferably 40 wt.%, and • the boiling point of the basic organic nitrogen compound(s) used is equal to or greater than the boiling point of the water and less than the boiling point of the fatty acids to be extracted.

[0011] The inventive process, when deacidifying oils or fats with a relatively high proportion of free fatty acids using aqueous solutions of organic bases, for example 2-dimethylaminoethanol, does not form a viscous soapstock if the amine content in the aqueous solution is high. Instead, under such conditions, both the oil phase and the extract phase are low-viscosity liquids. The phase separation occurs rapidly within a few minutes; the resulting phases are clear.

[0012] As demonstrated by experiments, the described extractive deacidification of crude esters from the acid-catalyzed process proceeds analogously. A rapid and complete phase separation was observed, yielding two clear and easily separable phases.

[0013] The process according to the invention is based on the process disclosed in DE 199 18 097 C2 for foodstuffs.

[0014] In contrast, a highly viscous soapstock formed when the aqueous solutions contained amines corresponding to the concentrations of sodium hydroxide used in chemical deacidification. Closer examination revealed that the basic nitrogen compound must contain at least approximately 40 wt% water for two phases to form in equilibrium with the oil being deacidified. Conversely, the concentration of the organic base, for example, 2-dimethylaminoethanol, in the aqueous solution must be at least approximately 20 wt% to prevent the formation of a viscous soapstock or cloudy phases. This means that, according to the invention, the aqueous solution used for deacidification must have an organic nitrogen compound content of approximately 20 wt% to approximately 60 wt%.

[0015] For example, if palm oil with a free fatty acid content of 4.5 wt% is mixed at 50°C with a 1:1 solution of 55 wt% 2-dimethylaminoethanol in water, the resulting oil, after separation of the phases, contains only 0.03 wt% free fatty acids after subtraction of the extraction solvent, with an oil loss of only 0.8 wt%. The extraction process according to the invention thus enables a temperature-controlled and efficient deacidification with minimal oil loss in just a few countercurrent stages.

[0016] Residual basic nitrogen compounds dissolved in the raffinate are preferably washed out with water or with dilute solutions of acetic, lactic, citric, sulfuric, or hydrochloric acid. Alternatively, traces of the basic extraction agents in the raffinate are removed by stripping with carbon dioxide. During stripping with carbon dioxide, the oil is simultaneously dried. The carbon dioxide can be used as a dilute gas or as a dense, supercritical gas to remove traces of the basic nitrogen compounds from the raffinate.

[0017] The extraction agent used according to the invention (for example, an aqueous solution of 2-dimethylaminoethanol) can be easily separated from the extract by distillation. This requires that the vapor pressure of the water is approximately equal to or higher than the vapor pressure of the basic nitrogen compound(s) used. The water and the basic organic compound are distilled off together, or preferably the water is distilled off first, whereby the ratio of basic compound to water remains constant or increases, and the formation of a viscous soapstock is avoided. If the vapor pressure of the basic compound were higher than the vapor pressure of the water, the ratio of basic compound to water would decrease, and ultimately, the formation of a viscous soapstock would occur.In other words, the boiling point of the basic nitrogen compound(s) must be equal to or higher than the boiling point of the water and lower than the boiling point of the fatty acids to be extracted.

[0018] If the aqueous amine is separated from this amine extraction phase by distillation, possibly under reduced pressure, the amine quasi-soaps are thermolytically cleaved and the free fatty acids and entrained oils remain in the distillation residue, while the aqueous amine passes over as an azeotrope and can be condensed.

[0019] Both the fatty acids and glycerides produced in the residue, as well as the condensed aqueous amine, can easily be recycled back into the process.

[0020] Suitable basic organic compounds for the process according to this invention should have the following properties: a) the compound should, if possible, not form amides with the free fatty acids; b) the compound should be miscible with water in any proportion; c) the boiling point of the compound should be equal to or higher than that of water; d) the odor nuisance from the aqueous solutions should be as low as possible. Examples of suitable organic nitrogen compounds are: N-methylmorpholine, 2-methylaminoethanol, 3-(diethylamino)-1-propanol, 2-diethylaminoethanol, 1-(dimethylamino)-2-propanol, dimethylformamide, 2-methylethylaminoethanol, 2-dibutylaminoethanol, dimethylformamide, morpholine, 2-diisopropylaminoethanol, etc. In general, tertiary amines are preferred to binary and singly substituted amines because of their higher basicity.

[0021] Examples of starting materials that can be readily deacidified using the process according to the invention include, in addition to raw materials from biodiesel production and crude esters from the acid-catalyzed biodiesel process, edible fats and oils such as beef tallow, lard, fish oil, corn oil, rendered animal fat, palm oil, soybean oil, rapeseed oil, sunflower oil, rice bran oil, cottonseed oil, olive oil, peanut oil, safflower oil, coconut oil, palm kernel oil, grapeseed oil, wheat germ oil, etc. Before using the process according to the invention, the oils and fats to be deacidified should be degummed and filtered, especially if more than 100 ppm of phosphatides are present. However, this is unnecessary for the acid-catalyzed esterification process according to Ingendoh, as this process is insensitive even to high phosphatide levels. The fat or oil processed in this way still contains dissolved oxygen, which should also be removed before further processing.Using the process according to the invention, the starting material is then deacidified while preserving temperature-sensitive compounds such as carotenes, tocotrienols, tocopherols, etc. These compounds, which are also nutritionally important, are largely destroyed or driven off during conventional physical refining, which is carried out using direct steam, due to the high temperatures.

[0022] In a slightly modified form, the inventive process is also ideally suited for removing free fatty acids from the steam condensates of fats and oils that have been deacidified by the aforementioned conventional physical refining, i.e. by steam deacidification, as well as waste fats, e.g. grease separator residues (“channel grease”, “brown grease”) or palm oil mill effluent (“POME”), from which not only the free fatty acids but also the contained water, which is carried away with the amine phase, can be removed with this method.

[0023] These steam condensates generally contain free fatty acids in very high concentrations, usually in the range of about 80 to 94 wt.%. Due to the high free fatty acid content, the extraction agent used according to the invention, i.e., the mixture of organic base and water, must be richer in the basic nitrogen compound than previously described in connection with the deacidification of fats and oils. The proportion of the organic nitrogen compound in the extraction agent should be at least about 40 wt.%. If such an aqueous solution rich in basic nitrogen compound, for example, 60 wt.% 2-dimethylaminoethanol and 40 wt.% water, is added to the liquid steam condensate as an extraction agent, a liquid, homogeneous mixture is obtained.One to four parts, preferably two to four parts, of an alkane and / or an ester, in particular an ethyl acetate, are then added to a portion of this liquid mixture. This process transforms the previously homogeneous mixture into two coexisting liquid phases, the aqueous phase of which contains the free fatty acids with high selectivity.

[0024] The alkane and / or ester phase essentially contains dissolved fats and oils present in the steam condensate. Byproducts also dissolved in the steam condensate, such as tocopherols, tocotrienols, and phytosterols, likewise pass into the alkane phase with high selectivity. The aqueous phase, containing free fatty acids, has a low viscosity, so phase separation occurs approximately 20 minutes after mixing is interrupted.

[0025] The raffinate (alkane phase or ester phase) obtained after separation of the aqueous phase is highly enriched with byproducts such as tocopherols, phytosterols, and tocotrienols, depending on the starting material. These valuable byproducts can be extracted from such concentrates under economically attractive conditions.

[0026] Suitable alkanes include propane, butane, hexane, petroleum ether, heptane, heptane fractions, octane, etc. When using butane or propane as a solvent for the formation of two phases, the pressure in the mixing vessel must at least equal the respective vapor pressure to ensure that the butane or propane is in liquid form. Particularly suitable esters include ethyl acetate, propyl acetate, butyl acetate, or a mixture thereof.

[0027] In the process according to the invention, the addition of alkanes is generally necessary when the concentration of free fatty acids in the starting material to be treated (oil, grease, or steam condensate) exceeds approximately 50% by weight, in order to maintain the two-phase nature of the overall system (starting material and extraction solvent). The addition of alkanes or esters thus ensures the formation of two easily handled liquid phases even at high concentrations of free fatty acids in the starting mixture, and extracts with high concentrations of free fatty acids can be obtained by countercurrent extraction using the extraction solvent employed according to the invention. Consequently, the solvent ratio can be low, which has a beneficial effect on the economic efficiency of the process according to the invention.

[0028] An embodiment of the process according to the invention is explained in more detail with reference to the single figure showing a process flow diagram. A starting product (oil, grease, or steam condensate) is fed to a first extraction column 12 via a line 10. In the extraction column 12, the free fatty acids are extracted from the starting product with high selectivity using an extraction solvent consisting of a mixture of a basic nitrogen compound and water. The extraction solvent used contains at least about 20 wt% and at most about 60 wt% of the organic nitrogen compound (organic base). Concentrations of the basic nitrogen compound of about 40 wt% are particularly advantageous.

[0029] The oil or fat, now free of free fatty acids, is fed through a line 14 to a washing column 16 (extraction column), where residual basic nitrogen compound is washed out with water or an aqueous solution containing an acid. The raffinate exits the washing column 16 as raffinate R. The washing solution exiting the top of the washing column 16 through a line 18 is then processed by distillation in a distillation column 20. During this process, water and any volatile acid dissolved in the water (such as acetic acid) are distilled off until the bottom product of the distillation column 20 reaches the composition of the extraction solvent. This bottom product is then fed through a line 22 to the extraction solvent cycle described below, while the distillate from the distillation column 20 is fed as washing liquid through a line 24 to the aforementioned washing column 16.

[0030] The extraction solvent containing the free fatty acids, drawn off at the top of extraction column 12, is fed to a second distillation column 28 via line 26. Water and the basic nitrogen compound are obtained as the overhead product during distillation in distillation column 28, while the extract containing the extracted free fatty acids and some neutral oil is drawn off as the bottom product from distillation column 28 via line 30. The overhead product of distillation column 28 is fed as the extraction solvent to extraction column 12 via line 32, where the extraction of the free fatty acids takes place, thus completing the extraction solvent cycle. The energy required for distillation is supplied to distillation columns 20 and 28 in the form of heating steam via lines 34 and 36.

[0031] In this way, an acid-free oil or fat is produced as a raffinate through extraction, along with the extracted free fatty acids, which still contain small amounts of neutral oil, in a closed-loop system for all auxiliary materials. No waste streams are generated. By-products contained in the starting product, such as tocopherols, tocotrienols, carotenes, phytosterols, cholesterol, etc., remain in the raffinate R.

[0032] A series of experiments were carried out using the method according to the invention, which are explained below. Example 1

[0033] 250 g of an oil consisting of 95.5 wt% neutral oil, 4.2 wt% free fatty acids, and 1.7 wt% tocopherol were mixed with 100 g of 2-dimethylaminoethanol and 70 g of water by stirring at 50°C. After interrupting the mixing process and separating the two liquid phases, samples were taken from both phases and analyzed. The phase rich in extraction solvent contained, after subtracting the extraction solvent, 53.7 wt% neutral oil, 45.0 wt% free fatty acids, and 0.3 wt% tocopherol. The oil-rich raffinate phase contained, after subtracting the extraction solvent, 98.2 wt% neutral oil, 0.05 wt% free fatty acids, and 1.8 wt% tocopherol. Example 2

[0034] 200 g of an oil containing 5.5 wt% free fatty acids and 1.8 wt% tocopherols was mixed at 50°C with 150 g of an extraction solvent containing 40 wt% water and 60 wt% 2-dimethylaminoethanol. After interrupting the mixing process and separating the phases, a sample was taken from each of the two coexisting liquid phases and analyzed. The extract phase had a loading of 8.9 wt%. After subtracting the extraction solvent, the extract consisted of 92 wt% free fatty acids, 0.3 wt% tocopherols, and 7.7 wt% glycerides. The raffinate phase, after subtracting the extraction solvent, contained 0.05 wt% free fatty acids, 1.8 wt% tocopherols, and 98.2 wt% glycerides. Example 3

[0035] 200 g of an oil containing 5.1 wt% free fatty acids and 0.3 wt% tocopherol were mixed with an extraction solvent consisting of 100 g water and 100 g pyridine at 60°C. After interrupting the mixing process and separating the phases, a sample was taken from each of the two coexisting liquid phases and analyzed. The extraction solvent loading was 2.1 wt%. The extract, after subtracting the extraction solvent, consisted of 20.8 wt% free fatty acids, 0.3 wt% tocopherols, and 95.8 wt% glycerides. The raffinate, after subtracting the extraction solvent, contained 4.2 wt% free fatty acids, 0.3 wt% tocopherols, and 95.1 wt% glycerides. Example 4

[0036] 151 g of an oil composed of 4.3 wt% free fatty acids, 1.4 wt% tocopherol, 0.6 wt% stigmasterol, and 93.7 wt% neutral oil were mixed at 50°C with 150 g of an extraction solvent consisting of 60 wt% 2-(dimethylamino)ethanol and 40 wt% water. After mixing, two phases separated over approximately 10 minutes. Following centrifugation to remove slight turbidity, samples were taken from both phases and analyzed. The extract phase, after subtracting the extraction solvent, had the following composition: 84 wt% free fatty acids, 0.5 wt% tocopherol, 0.5 wt% stigmasterol, and 15 wt% neutral oil. The raffinate contained 0.05 wt% free fatty acids, 1.4 wt% tocopherol, 0.6 wt% stigmasterol, and 97.95 wt% neutral oil. The extract contained 0.46% by weight of the amount of neutral oil used. Example 5

[0037] 300 g of palm oil containing 4.5 wt% free fatty acids, 0.4 wt% tocopherols, 0.15 wt% stigmasterol, and 94.95 wt% neutral oil were mixed with 42 g of an extraction solvent consisting of 60 wt% 2-dimethylaminoethanol and 40 wt% water at 50°C. After interrupting the mixing process and allowing phase separation for approximately 35 minutes, samples were taken from both phases and analyzed. The extract, after subtracting the extraction solvent, contained 40.0 wt% free fatty acids, 0.4 wt% tocopherols, 0.25 wt% stigmasterol, and 59.35 wt% neutral oil. The refined product, after subtracting the extraction solvent, consisted of 0.3 wt% free fatty acids, 0.4 wt% tocopherols, 0.1 wt% stigmasterol, and 99.4 wt% neutral oil. 6 wt% of the neutral oil used was contained in the extract. The solvent ratio was a low 0.14. Example 6

[0038] Palm oil was fed into the first extraction column 12 at a rate of 30.0 kg / h in a system as shown in the accompanying figure. Since the palm oil contained 4.3 wt% free fatty acids, the feed through line 10 consisted of 28.71 kg / h neutral oil and 1.29 kg / h free fatty acids. In extraction column 12, the palm oil was brought into contact with 30.0 kg / h of extraction solvent in a countercurrent flow at 80°C. The extraction solvent consisted of dimethylaminoethanol (DMAE) and

[0039] The raffinate stream exiting extraction column 12 consisted of 24.424 kg / h neutral oil, 0.090 kg / h free fatty acids, 0.855 kg / h DMAE, and 0.855 kg / h water. The extract stream comprised 14.145 kg / h DMAE, 14.145 kg / h water, 0.285 kg / h neutral oil, and 1.20 kg / h free fatty acids.

[0040] The raffinate stream was fed to washing column 16, where the DMAE was washed out at 80°C with 15.0 kg / h of water in a countercurrent flow. The purified raffinate stream exited washing column 16 with the following composition: 28.424 kg / h neutral oil, 0.012 kg / h DMAE, and less than 0.025 kg / h free fatty acids. This corresponds to a neutral oil with 0.00042 wt% DMAE and less than 0.00088 wt% free fatty acids. The wash water exited washing column 16 with the following composition: 15.855 kg / h water, 0.855 kg / h DMAE, and 0.064 kg / h free fatty acids. The wash water was regenerated in distillation column 20 at 100°C. The overhead product, 15.0 kg / h of water, was recycled through line 24 into washing column 16. The bottoms product, containing 0.855 kg / h of water and 0.855 kg / h of DMAE, was combined with the extract stream flowing through line 26 from extraction column 12.

[0041] The extract stream from extraction column 12, combined with the bottom product from distillation column 20, was fed to distillation column 28. The overhead product of distillation column 28, consisting of 15.0 kg / h water and 15.0 kg / h DMAE, was returned to extraction column 12 via line 32 as the extraction solvent. The bottom product exiting distillation column 28 was 0.285 kg / h neutral oil and 1.264 kg / h free fatty acids. The extract therefore consisted of 18.4 wt% neutral oil and 81.6 wt% free fatty acids.

[0042] The extraction solvent cycle is therefore closed, and there are no waste disposal problems. Example 7

[0043] 100 ml of steam condensate from palm oil refining was extracted at 80°C with 200 ml of a 1:1 mixture of dimethylaminoethanol and water. 300 ml of heptane was added to this solution to create two liquid phases. The water- and DMAE-rich phase (extract phase) contained 22 wt% dissolved components. The heptane-rich phase (raffinate phase) had a loading of 7 wt%. The material dissolved in the raffinate phase contained 3% fatty acids, 0.4% α-tocopherol, and 1.5% tocotrienols. By comparison, the material dissolved in the extract phase contained 65% fatty acids, 0.05% α-tocopherol, and 0.2% tocotrienols. Example 8

[0044] 100 ml of crude ester from the acid-catalyzed process of Ingendoh were stirred intensively with 100 ml of a mixture of equal mass fractions of dimethylaminoethanol and water at 50°C for a period of 1 hour, and the decrease in the FFA content in the crude ester was determined titrimetrically by determining the acid number at various time points, yielding the following results: Initial value (0 min)−SZ=7.3[mg KOH / g] after 5 min - SZ = 0.63 after 10 min - SZ = 0.46 after 20 min - SZ = 0.35 after 45 min - SZ = 0.37 after 60 min - SZ = 0.55

[0045] This demonstrated that even exceptionally high FFA content crude esters can be reduced below the limit value of 0.5 mg KOH / g according to DIN-EN 14 214 within 10 minutes using this methodology.

[0046] Phase separation occurred practically spontaneously at 50°C and yielded clear phases after a few minutes, which could be easily separated in the separating funnel.

[0047] The amine subphase was easily separated from the extracted fatty acids and entrained glycerides by vacuum distillation in a rotary evaporator. The condensate could be readily used for re-extraction, while the free fatty acids remaining after distillation could be directly recycled into the acid-catalyzed esterification process. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 1 183 225 B1

[0005] EP 2 464 715 B1

[0006] DE 199 18 097 C2

[0013] Cited non-patent literature

[0000] Jon Van Gerpen, Gerhard Knothe: Basics of the Transesterification Reaction in: Gerhard Knothe, Jon Van Gerpen, Jürgen Krahl: The Biodiesel Handbook, pp. 26-41, AOCS Press, 2005

[0004]

Claims

[1] Method for removing free fatty acids and optionally water from the oils and fats used for the production of biodiesel and from the crude esters produced during the production of biodiesel by extracting the free fatty acids with a mixture of basic organic nitrogen compounds and water as an extraction agent, wherein • the extraction is carried out at a temperature below the boiling point of the organic nitrogen compounds, • the proportion of basic organic nitrogen compounds in the extraction solvent is at least 20 wt.% and at most 60 wt.%, preferably 40 wt.%, and • the boiling point of the basic organic nitrogen compound(s) used is equal to or greater than the boiling point of the water and less than the boiling point of the fatty acids to be extracted. [2] Method according to claim 1, characterized bythat tertiary amines are used as basic organic nitrogen compounds. [3] Method according to any one of the preceding claims, characterized by that as a basic, organic nitrogen compound 2-dimethylamino-ethanol, 2-methylamino-diethanol, 4-methylmorpholine, 2-diisopropylaminoethanol, 2-dibutylamino-ethanol, 3-dimethylamino-propanol, 1-dimethylamino-2-propanol, 2-dimethylamino-ethanol, 2-dimethylamino-1-butanol, 2-(Methylethylamino)-ethanol, dimethylformamide, morpholine, pyridine, 2-dimethylamino-2-methyl-1-propanol, 4-methyl-pyridine, 1-methyl-pyrrole, 2-dibutylamino-ethanol, 2-dimethylamino-ethylamine, monoethanolamine, 3-dimethylamino-1-propanol, dimethylamino-2-propanone, 1-Dimethylamino-1-propylenamine, or a mixture of these compounds is used. [4] Method according to any one of the preceding claims, characterized by, that the aqueous-aminic extraction solvent with the extracted free fatty acids contained therein is recovered from the extraction solvent phase separated by sedimentation or centrifugation by distillation at normal pressure or reduced pressure, and that the components thus obtained are returned to the extraction or production process. [5] Method according to any one of the preceding claims, characterized by , that from raw materials, intermediate or end products of biodiesel production, in which no alkaline glycerol phase is produced, e.g. in the Ingendoh process, acidic ingredients, especially FFAs, are separated by amine agents in order to obtain a product that meets DIN-EN 14 214.

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