AMENDMENTS TO THE IMSBC CODE, INCLUDING EVALUATION OF PROPERTIES OF SOLID BULK CARGOES. Dried Distillers Grains with Solubles (DDGS)

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1 E SUB-COMMITTEE ON DANGEROUS GOODS, SOLID CARGOES AND CONTAINERS 15th session Agenda item 4 DSC 15/4/2 7 June 2010 Original: ENGLISH AMENDMENTS TO THE IMSBC CODE, INCLUDING EVALUATION OF PROPERTIES OF SOLID BULK CARGOES Dried Distillers Grains with Solubles (DDGS) Submitted by the United States SUMMARY Executive summary: This document contains a proposal to include a new schedule in the IMSBC Code for the safe carriage of distillers dried grains with solubles (DDGS) in bulk Strategic direction: 5.2 High-level action: Planned output: Action to be taken: Paragraph 20 Related documents: None Background 1 On December 19, 2007, the President of the United States signed into law the Energy Independence and Security Act of This legislation called for increased production of ethanol and other renewable fuels with a 2010 production goal for ethanol of 12 billion gallons per year. By 2015 the production goal will increase to 15 billion gallons a year; this is a 25% increase in production. As a result of the increased demand for ethanol, a surplus of co-products such as distillers dried grains with solubles (DDGS) is rapidly increasing in the United States. DDGS is used as animal feed and is increasingly being exported in bulk to various countries around world. Ethanol Production Process 2 Ethanol is produced by either a dry milling process or a wet milling process. DDGS and carbon dioxide are co-products of the dry milling process that produces mainly ethanol. Corn gluten meal and corn gluten feed are the co-products of the wet milling process that produces corn syrup, corn starch and ethanol.

2 Page 2 3 In dry milling, the entire corn kernel or other starchy grain is first ground into flour, which is referred to in the industry as "meal" and processed without separating out the various component parts of the grain. The meal is slurried with water to form a "mash". Enzymes are added to the mash to convert the starch to dextrose, a simple sugar. Ammonia is added for ph control and as a nutrient. The mash is processed in a high-temperature cooker to reduce bacteria levels ahead of fermentation. The mash is cooled and transferred to fermenters where yeast is added and the conversion of sugar to ethanol and carbon dioxide begins. The fermentation process generally takes about 40 to 50 hours. During this part of the process, the mash is agitated and kept cool to facilitate the activity of the yeast. After fermentation, the resulting "beer" is transferred to distillation columns where the ethanol is separated from the remaining "stillage". The stillage is sent through a centrifuge that separates the coarse grain from the solubles. The coarse grain without further processing or drying is commonly referred to as Wet Distillers Grain (WDG). The solubles are then concentrated to about 30% solids by evaporation, resulting in Condensed Distillers Solubles (CDS) or "syrup". The coarse grain and the syrup are then dried together to produce DDGS. Discussion on product distinction 4 DDGS is not produced by mechanically expelling seeds or by solvent extraction and is generally not considered a seedcake. The DDGS production process can be best described as a co-product of fermentation. DDGS is not listed under any of the SEEDCAKE schedules nor is it listed anywhere else in the IMSBC Code. On this basis it has been treated as an unlisted cargo and the general provisions of 1.3 of the IMSBC Code apply. 5 Brewer's grain pellets are listed under the SEEDCAKE schedules; however, this cargo is not the same as DDGS. Brewer's grain pellets are the by-product of consumer beer production using corn grits, barley malt, and other ingredients. The multiple ingredients in this process results in a residue mash that has low bulk density. A binder is added to the residue mash of this fermentation process and then it is compressed under high pressure in pelletizing machines in order to improve transport efficiency. These pellets share many of the same properties of other seedcake products when shipped in bulk. 6 Unlike consumer beer production, the ethanol production process is designed to maximize alcohol production and alcohol yield per bushel of corn. As mentioned above, DDGS is the result of using the whole corn kernel and further processing the resultant mash through a centrifuge, separating the coarse grain from the solubles, and drying the syrup and course grain together to improve shelf life and to make it viable as animal feed. DDGS does contain enough bulk density to transport efficiently without pelletizing the product. Test Results 7 Twenty random samples of DDGS were tested at 140 C for a 24 hour period in accordance with the UN N.4 self-heating test as contained in the UN Manual of Tests and Criteria. The results of the tests are as follows: # Sample ID Moisture in sample Oil in sample Oil plus moisture Highest temperature observed during 24 hour test period ( C) Max temperature increase over test temperature ( C) 1 RMG-A RMG-B RMG-C RMG-D RMG-E RMG-F

3 # Sample ID Moisture in sample Oil in sample Oil plus moisture Highest temperature observed during 24 hour test period ( C) DSC 15/4/2 Page 3 Max temperature increase over test temperature ( C) 7 RMG-G RMG-H RMG-I RMG-J RMG-K RMG-L RMG-M RMG-N RMG-O RMG-P RMG-Q RMG-R RMG-S RMG-T A material is considered a hazard class 4.2 self-heating substance if the temperature of the material rises more than 60 C above the oven temperature at any point during the 24 hour test period. All samples reached peak temperatures and then stabilized to around the oven temperature. None of the samples tested met the classification criteria for inclusion in hazard class UN N.1 preliminary screening was conducted on three DDGS test samples in order to determine whether or not DDGS is readily combustible or whether additional testing is required. A strip of the test sample approximately 20 mm wide, 10 mm high, and 250 mm long is subjected to ignition as one end by application of a propane ignition flame for 2 minutes. The results are as follows: Sample ID Test Period Combustion Distance Sample 1 2 minutes 23 mm Sample 2 2 minutes 25 mm Sample 3 2 minutes 28 mm During the preliminary screening the material was observed to burn and glow when in direct contact with the ignition flame. Combustion extended 23, 25 and 28 mm for samples 1, 2, and 3 respectively, from the starting end as evidenced by blackening and a dark brown discoloration of the surface of the strip. No smouldering was observed during the test and when the ignition source was removed after the two minute test period, combustion ceased with no evidence of smoking. The test strip cooled rapidly when the ignition source was removed. Upon probing through the surface of the test strip, we observed that only the surface of the test strip was burnt and the sample material 2-3 mm underneath where flame had been applied had no charring. The product remained in its natural state. 9 Additional UN N.4 tests were conducted with additional samples of DDGS. Some of these tests were conducted using larger sample cubes and lower oven temperatures in order to better reflect bulk transportation and the conditions likely to be experienced during transport. The results are as follows:

4 Page 4 Sample ID Sample size (mm) Test temp ( C) Moisture in sample Oil in sample Oil plus moisture Highest temperature observed during 24 hour test period ( C) Max temperature increase over test temperature ( C) RMG RMG RMG RMG RMG RMG RMG All samples reached peak temperatures and then stabilized to around the oven temperature. None of the samples tested met the classification criteria for inclusion in hazard class 4.2. Vessel shipment monitoring 10 The temperatures on the following ocean vessels were checked at destination ports: Vessel Name Month Loaded Total Quantity M/T Average Temperature during the voyage ( C) MV SENANUR CEBI 9/ MV SOLENT 10/ MV CLIPPER MERMAID 11/ MV VERGINA 12/ MV CHIOS STAR 2/ MV KARMEN 3/ MV DORA 4/ MV ELEFTHERIA 4/ An oxygen monitor was placed into a sealed hold containing DDGS on the MV Chios Star on April 29, The oxygen monitor recorded oxygen levels in the hold throughout the voyage and when the destination was reached on May 11, 2010, recording was ceased. The initial oxygen level in the hold containing DDGS was 20.9% and the final oxygen level at destination was 19.3%. Oxygen was reduced by 1.6%. Shipping History and Experience 12 DDGS has been shipped in bulk as non-hazardous cargo for more than 25 years without any incidents. A query of the Lloyd's Casualty Database was conducted covering the period beginning on January 1, 2000 and ending on May 18, The query did not reveal any reported causalities or incidents involving DDGS as a result of self-heating, spontaneous combustion or oxygen depletion. Discussion on cargo properties 13 While DDGS exhibits some self-heating during the UN N.4 laboratory tests conducted at 140 C, the cargo is not known to self-heat under normal transport conditions. Additional self-heating tests were conducted on 200 mm and 300 mm cube samples at lower

5 Page 5 temperatures of 75 C and 100 C and no self-heating was observed. Temperature monitoring was also conducted and no self-heat was observed. The UN N.1 laboratory test results illustrate that even if some self-heating were to occur, DDGS would not spontaneously combust. Furthermore, if a source of ignition is introduced into the cargo, a fire is unlikely to occur and it is even less likely that it would propagate. 14 DDGS is not likely to deplete oxygen in the hold during carriage as indicted by the results of the oxygen monitoring conducted. A 1.6% reduction in oxygen during the course of a voyage is a common occurrence for any enclosed space and, therefore, oxygen depletion is not considered a property of the cargo. 15 DDGS is used as animal feed. As such, the cargo presents no toxic hazards to humans or the environment during transportation. DDGS dust in air suspension may cause minor irritation upon respiration or skin contact but short and long term health effects are expected to be minimal. Protective clothing and equipment are generally not required. 16 Concentrated DDGS dust in air suspension may become explosive under confined conditions. This property is common for grain products. However, dust generation is likely to occur only during loading, unloading and handling operations. These operations are conducted in the open thereby negating the risk of an explosion. 17 DDGS is a cohesive cargo. The natural angle of a freely poured pile of DDGS with the horizontal exceeds 30 degrees with an average value of 45 degrees. Through experience much steeper angles have been observed due to caking. The flow ability of DDGS during carriage by vessel is very low. Classification conclusions 18 DDGS is a cargo that may exhibit minor self-heating when transported in bulk by vessel but evidence suggests that the probability of a fire with this cargo is very low. DDGS is cohesive and will not liquefy or shift during carriage. On this basis, DDGS should be classified as non-hazardous and assigned to group C. Proposal 19 It is proposed to include a new schedule for DDGS in Appendix A of the IMSBC Code. A draft schedule for DDGS has been prepared in accordance with and appears in annex 2 of this document. Action requested of the Sub-Committee 20 The Sub-Committee is invited to consider the proposal set forth in paragraph 19 and take action as appropriate. ***

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7 Annex 1, page 1 ANNEX 1 U.S. DDGS EXPORTS metric tons North America 234, ,408 1,027,080 1,982,713 2,262,582 East Asia 49, , , ,104 1,220,687 Southeast Asia 125, , , , ,596 Middle East 48,151 18, , , ,856 Central America 5,208 27,642 31, , ,714 Caribbean 10,965 1,390 93, , ,979 North Africa 5,545 27,858 46, , ,680 European Union , , , , ,575 South America 16,751 10,454 60, ,224 88,967 South Asia 126 2,601 3,635 1,061 6,326 Other Europe 0 5 3, ,026 Oceania Sub-Saharan Africa 1,137 3,403 1, Grand Total 1,069,211 1,253,653 2,358,248 4,532,352 5,640,901

8 Annex 1, page 2 DDGS Dry Milling Process DDGS UN N.1 Testing Photographs

9 Annex 1, page 3 DDGS Vessel Loading Photographs ***

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11 Annex 2, page 1 ANNEX 2 DISTILLERS DRIED GRAINS WITH SOLUBLES (DDGS) DESCRIPTION A dried blend of coarse grains and condensed distillers solubles that remain after the fermentation of the starch fraction of corn with yeasts and enzymes to produce ethanol and carbon dioxide. Yellowish brown in colour with a cooked corn odour. Moisture content not more than 12.0% and oil content not more than 11.0%. This schedule is not applicable to wet distillers grain (WDG) and distillers dried grain (DDG). CHARACTERISTICS ANGLE OF REPOSE BULK DENSITY (kg/m 3 ) STOWAGE FACTOR (m 3 /t) Not applicable 450 to to 2.22 SIZE CLASS GROUP Not applicable Not applicable C HAZARD This cargo is non-combustible or has a low fire risk. STOWAGE AND SEGREGATION No special requirements. HOLD CLEANLINESS Clean and dry as relevant to the hazards of the cargo. WEATHER PRECAUTIONS This cargo shall be kept as dry as practicable. This cargo shall not be handled during precipitation. During handling of this cargo all non-working hatches of the cargo spaces into which this cargo is loaded shall be closed. LOADING Load in open unconfined areas. Trim in accordance with the relevant provision required under sections 4 and 5 of the Code. PRECAUTIONS No special requirements. VENTILATION No special requirements.

12 Annex 2, page 2 CARRIAGE Hatches of the cargo spaces carrying this cargo shall be weathertight to prevent the ingress of water. DISCHARGE If this cargo has hardened, it shall be trimmed to avoid the formation of overhanging faces, as necessary. CLEAN-UP No special requirements.