Project Element 6: Kraft Liquor Trials. As a condition of receiving DOE funding, there also will be a trial on Kraft black liquor. This trial will be detailed at a later date; however, it is anticipated that the trial will take place after start-up of the gasification system and not last more than three weeks (500 operating hours). Georgia-Pacific anticipates some gasification system downtime during the Kraft liquor trial, such as to make adjustments to optimize gasification operations. As a result, the total time period encompassing the 500-hour Kraft trial could be as much as 1500 hours. During the trial, the Mill will process the Kraft liquor through one of the gasification vessels, while the other vessel remains out of service. The Kraft liquor feed to the gasification system will be limited to allow the gas clean-up equipment to maintain adequate performance. Georgia-Pacific will maintain the emissions from the stack at or below the total levels stated in the construction permit for the gasification system. This will be accomplished by a combination of limiting the amount of Kraft liquor processed as well as temporary modifications to the equipment or process. During the trial phase, it will be necessary to maintain separation of the process chemicals of the trial liquor and the Mill liquor. To do that, the smelters will need to be operated during this time period to process the Mill’s black liquor. Therefore, the Mill will be processing more liquor during this time period than is normal and the emissions will increase as well. The excess green liquor produced, as well as any sulfur containing green liquor from the H2S Absorber, will be returned to the facility that supplies the Kraft liquor. Flexibility required for this project element is described in Section IV.A. Georgia-Pacific will work with the Forest Service to determine the time that will have the least impact on the Class I Wilderness area and will attempt to hold the trials at that time.
