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BIO-SURF NITRIFICATION OF CONCENTRATED AMMONIA-BRINE WASTE FROM AN IODINE MANUFACTURING PLANT Charles C.-S. Chou, Manager New Products Development Autotrol Corporation MUwaukee, Wisconsin 53209 T. Daicho, Process Engineer Nippon Autotrol Kabushiki Kaisha Tokyo, Japan INTRODUCTION Nippon Chemicals Company is a major producer of halogens and halogenated organics in Japan. Its iodine plant, located in Chiba Prefecture, 100 kilometers east of Tokyo, obtains the halogen from an iodide-rich brine. Various agricultural, medicinal and industrial chemicals are synthesized from iodine, bromine and natural gas. The brine contains approximately 100 mg/1 sodium iodide. A blowing-out process is employed for the recovery of iodine in which iodide is oxidized by gaseous chlorine and stripped out of the brine liquor. Iodine is subsequently purified and crystallized as starting material for many downstream uses. In the past, the waste brine was discharged into a river after iodine recovery. This wastewater contains salt as concentrated as sea water and has about 200 mg/1 ammonia nitrogen [lj. There are a few iodine plants in the same area and all have discharged their wastewater directly into the nearby river. The river has also been a source of irrigation water. The high salinity and ammonia content of the river water during rice growing season, when the river flow rate is low, has had adverse effect on the crop. Therefore, the iodine works had kept the flow rate of wastewater in accordance with that of the river water, although no legal restriction on this river was enacted as to the discharge level of ammonia and salt concentration. However, it was difficult to regulate the discharge flow due to the variation of iodine production. Consequently, a common pipe line was laid to transport the brine waste directly into an estuary several kilometers away on the seashore of the Pacific Ocean. As a preventive measure, these iodine plants have worked out a discharge limit with a fishermen's union and the prefectural government, since active fishing has been conducted at the estuary and near the seashore. The agreement restricts ammonia nitrogen to less than 1 10 mg/1. To meet the ammonia discharge level, Nippon Chemicals Company has conducted a rather extensive feasibility study on several alternative treatment processes. The rotating biological contactor (RBC), activated sludge process and an ammonia stripping system were selected for the study. After thorough pilot testing and cost comparison, the company came to a conclusion that the RBC was the most cost-effective process because of its lowest total cost, minimal secondary pollution, simple operation and maintenance procedures and ease of future expansion. This chapter will discuss the initial pilot study, design rationale and the operating experience of the full-scale RBC treatment. NITRIFICATION OF CONCENTRATED AMMONIA OR HIGH SALINITY WASTES In the 1970s attention was extended to high-strength ammonia waste. Lue-Hing and his colleagues conducted a nitrification study of digester supernatant by a 0.5-m-diameter 4- 48
Object Description
Purdue Identification Number | ETRIWC198106 |
Title | Bio-surf nitrification of concentrated ammonia-brine waste from an iodine manufacturing plant |
Author |
Chou, Charles Chi-Su Daicho, T. |
Date of Original | 1981 |
Conference Title | Proceedings of the 36th Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://e-archives.lib.purdue.edu/u?/engext,32118 |
Extent of Original | p. 48-55 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Date Digitized | 2009-07-07 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 48 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | BIO-SURF NITRIFICATION OF CONCENTRATED AMMONIA-BRINE WASTE FROM AN IODINE MANUFACTURING PLANT Charles C.-S. Chou, Manager New Products Development Autotrol Corporation MUwaukee, Wisconsin 53209 T. Daicho, Process Engineer Nippon Autotrol Kabushiki Kaisha Tokyo, Japan INTRODUCTION Nippon Chemicals Company is a major producer of halogens and halogenated organics in Japan. Its iodine plant, located in Chiba Prefecture, 100 kilometers east of Tokyo, obtains the halogen from an iodide-rich brine. Various agricultural, medicinal and industrial chemicals are synthesized from iodine, bromine and natural gas. The brine contains approximately 100 mg/1 sodium iodide. A blowing-out process is employed for the recovery of iodine in which iodide is oxidized by gaseous chlorine and stripped out of the brine liquor. Iodine is subsequently purified and crystallized as starting material for many downstream uses. In the past, the waste brine was discharged into a river after iodine recovery. This wastewater contains salt as concentrated as sea water and has about 200 mg/1 ammonia nitrogen [lj. There are a few iodine plants in the same area and all have discharged their wastewater directly into the nearby river. The river has also been a source of irrigation water. The high salinity and ammonia content of the river water during rice growing season, when the river flow rate is low, has had adverse effect on the crop. Therefore, the iodine works had kept the flow rate of wastewater in accordance with that of the river water, although no legal restriction on this river was enacted as to the discharge level of ammonia and salt concentration. However, it was difficult to regulate the discharge flow due to the variation of iodine production. Consequently, a common pipe line was laid to transport the brine waste directly into an estuary several kilometers away on the seashore of the Pacific Ocean. As a preventive measure, these iodine plants have worked out a discharge limit with a fishermen's union and the prefectural government, since active fishing has been conducted at the estuary and near the seashore. The agreement restricts ammonia nitrogen to less than 1 10 mg/1. To meet the ammonia discharge level, Nippon Chemicals Company has conducted a rather extensive feasibility study on several alternative treatment processes. The rotating biological contactor (RBC), activated sludge process and an ammonia stripping system were selected for the study. After thorough pilot testing and cost comparison, the company came to a conclusion that the RBC was the most cost-effective process because of its lowest total cost, minimal secondary pollution, simple operation and maintenance procedures and ease of future expansion. This chapter will discuss the initial pilot study, design rationale and the operating experience of the full-scale RBC treatment. NITRIFICATION OF CONCENTRATED AMMONIA OR HIGH SALINITY WASTES In the 1970s attention was extended to high-strength ammonia waste. Lue-Hing and his colleagues conducted a nitrification study of digester supernatant by a 0.5-m-diameter 4- 48 |
Resolution | 300 ppi |
Color Depth | 8 bit |
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