Composition and Property Measurements for PHA Phase 4 Glasses

Composition and Property Measurements for PHA Phase 4 Glasses

Author:

Publisher:

Published: 2000

Total Pages: 82

ISBN-13:

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The results presented in this report are for nine Precipitate Hydrolysis Aqueous (PHA) Phase 4 glasses. Three of the glasses contained HM sludge at 22, 26, and 30 wt% respectively, 10 wt% PHA and 1.25 wt% monosodium titanate (MST), all on an oxide basis. The remaining six glasses were selected from the Phase 1 and Phase 2 studies (Purex sludge) but with an increased amount of MST. The high-end target for MST of 2.5 wt% oxide was missed in Phases 1 and 2 due to (approximately)30 wt% water content of the MST. A goal of this Phase 4 study was to determine whether this increase in titanium concentration from the MST had any impact on glass quality or processibility. Two of the glasses, pha14c and pha15c, were rebatched and melted due to apparent batching errors with pha14 and pha15. The models currently in the Defense Waste Processing Facility's (DWPF) Product Composition Control System (PCCS) were used to predict durability, homogeneity, liquidus, and viscosity for these nine glasses. All of the HM glasses and half of the Purex glasses were predicted to be phase separated, and consequently prediction of glass durability is precluded with the cument models for those glasses that failed the homogeneity constraint. If one may ignore the homogeneity constraint, the measured durabilities were within the 95% prediction limits of the model. Further efforts will be required to resolve this issue on phase separation (inhomogeneity). The liquidus model predicted unacceptable liquidus temperatures for four of the nine glasses. The approximate, bounding liquidus temperatures measured for all had upper limits of 1,000 C or less. Given the fact that liquidus temperatures were only approximated, the 30 wt% loading of Purex may be near or at the edge of acceptability for liquidus. The measured viscosities were close to the predictions of the model. For the Purex glasses, pha12c and pha15c, the measured viscosities of 28 and 23 poise, respectively, indicate that DWPF processing may be compromised at the low end of the viscosity range (20 poise). Although the HM sludge glass examined (10 wt% PHA) had a measured viscosity of (approximately)90 poise, the HM glasses at 7wt% PHA are predicted to be higher than the 100 poise limit for DWPF. Further work will be required to resolve these issues.


Summary of Results for PHA Glass Study

Summary of Results for PHA Glass Study

Author:

Publisher:

Published: 2000

Total Pages: 5

ISBN-13:

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This report provides a summary of the results obtained for a limited variability study for glasses containing Precipitate Hydrolysis Aqueous, Monosodiumtitanate, and either simulated Purex or HM sludge.


Comprehensive Biotechnology

Comprehensive Biotechnology

Author:

Publisher: Newnes

Published: 2011-08-26

Total Pages: 5304

ISBN-13: 0080885047

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The second edition of Comprehensive Biotechnology, Six Volume Set continues the tradition of the first inclusive work on this dynamic field with up-to-date and essential entries on the principles and practice of biotechnology. The integration of the latest relevant science and industry practice with fundamental biotechnology concepts is presented with entries from internationally recognized world leaders in their given fields. With two volumes covering basic fundamentals, and four volumes of applications, from environmental biotechnology and safety to medical biotechnology and healthcare, this work serves the needs of newcomers as well as established experts combining the latest relevant science and industry practice in a manageable format. It is a multi-authored work, written by experts and vetted by a prestigious advisory board and group of volume editors who are biotechnology innovators and educators with international influence. All six volumes are published at the same time, not as a series; this is not a conventional encyclopedia but a symbiotic integration of brief articles on established topics and longer chapters on new emerging areas. Hyperlinks provide sources of extensive additional related information; material authored and edited by world-renown experts in all aspects of the broad multidisciplinary field of biotechnology Scope and nature of the work are vetted by a prestigious International Advisory Board including three Nobel laureates Each article carries a glossary and a professional summary of the authors indicating their appropriate credentials An extensive index for the entire publication gives a complete list of the many topics treated in the increasingly expanding field


Alternatives for High-Level Waste Salt Processing at the Savannah River Site

Alternatives for High-Level Waste Salt Processing at the Savannah River Site

Author: National Research Council

Publisher: National Academies Press

Published: 2000-11-30

Total Pages: 154

ISBN-13: 0309071941

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The Second World War introduced the world to nuclear weapons and their consequences. Behind the scene of these nuclear weapons and an aspect of their consequences is radioactive waste. Radioactive waste has varying degrees of harmfulness and poses a problem when it comes to storage and disposal. Radioactive waste is usually kept below ground in varying containers, which depend on how radioactive the waste it. High-level radioactive waste (HLW) can be stored in underground carbon-steel tanks. However, radioactive waste must also be further immobilized to ensure our safety. There are several sites in the United States where high-level radioactive waste (HLW) are stored; including the Savannah River Site (SRS), established in 1950 to produce plutonium and tritium isotopes for defense purposes. In order to further immobilize the radioactive waste at this site an in-tank precipitation (ITP) process is utilized. Through this method, the sludge portion of the tank wastes is being removed and immobilized in borosilicate glass for eventual disposal in a geological repository. As a result, a highly alkaline salt, present in both liquid and solid forms, is produced. The salt contains cesium, strontium, actinides such as plutonium and neptunium, and other radionuclides. But is this the best method? The National Research Council (NRC) has empanelled a committee, at the request of the U.S. Department of Energy (DOE), to provide an independent technical review of alternatives to the discontinued in-tank precipitation (ITP) process for treating the HLW stored in tanks at the SRS. Alternatives for High-Level Waste Salt Processing at the Savannah RIver Site summarizes the finding of the committee which sought to answer 4 questions including: "Was an appropriately comprehensive set of cesium partitioning alternatives identified and are there other alternatives that should be explored?" and "Are there significant barriers to the implementation of any of the preferred alternatives, taking into account their state of development and their ability to be integrated into the existing SRS HLW system?"


The Handbook of Polyhydroxyalkanoates

The Handbook of Polyhydroxyalkanoates

Author: Martin Koller

Publisher: CRC Press

Published: 2020-11-05

Total Pages: 453

ISBN-13: 1000173577

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The first volume of the "Handbook of Polyhydroxyalkanoates (PHA): Microbial Biosynthesis and Feedstocks" focusses on feedstock aspects, enzymology, metabolism and genetic engineering of PHA biosynthesis. It addresses better understanding the mechanisms of PHA biosynthesis in scientific terms and profiting from this understanding in order to enhance PHA biosynthesis in bio-technological terms and in terms of PHA microstructure. It further discusses making PHA competitive for outperforming established petrol-based plastics on industrial scale and obstacles for market penetration of PHA. Aimed at professionals and graduate students in Polymer (plastic) industry, wastewater treatment plants, food industry, biodiesel industry, this book Covers the intracellular on-goings in PHA-accumulating bacteria Assesses diverse feedstocks to be used as carbon source for PHA production including current knowledge on PHA biosynthesis starting from inexpensive waste feedstocks Summarizes recent relevant results dealing with PHA production from various organic by-products Presents the key elements to understand and fine-tune the microstructure and sequence-controlled molecular architecture of PHA co-polyesters Discusses the use of CO-rich syngas, sourced from various organic waste materials, for PHA biosynthesis


The Handbook of Polyhydroxyalkanoates, Three Volume Set

The Handbook of Polyhydroxyalkanoates, Three Volume Set

Author: Martin Koller

Publisher: CRC Press

Published: 2020-11-06

Total Pages: 1416

ISBN-13: 1000173593

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The Handbook of Polyhydroxyalkanoates (PHA) focusses on and addresses varying facets of PHA biosynthesis and processing, spread across three volumes. The first volume discusses feedstock aspects, enzymology, metabolism and genetic engineering of PHA biosynthesis. It addresses better understanding the mechanisms of PHA biosynthesis in scientific terms and profiting from this understanding in order to enhance PHA biosynthesis in bio-technological terms and in terms of PHA microstructure. It further discusses making PHA competitive for outperforming established petrol-based plastics on industrial scale and obstacles for market penetration of PHA. This second volume focusses on thermodynamic and mathematical considerations of PHA biosynthesis, bioengineering aspects regarding bioreactor design and downstream processing for PHA recovery from microbial biomass. It covers microbial mixed culture processes and includes a strong industry-focused section with chapters on the economics of PHA production, industrial-scale PHA production from sucrose, next generation industrial biotechnology approaches for PHA production based on novel robust production strains, and holistic techno-economic and sustainability considerations on PHA manufacturing. Third volume is on the production of functionalized PHA bio-polyesters, the post-synthetic modification of PHA, processing and additive manufacturing of PHA, development and properties of PHA-based (bio)composites and blends, the market potential of PHA and follow-up materials, different bulk- and niche applications of PHA, and the fate and use of spent PHA items. Divided into fourteen chapters, it describes functionalized PHA and PHA modification, processing and their application including degradation of spent PHA-based products and fate of these bio-polyesters during compositing and other disposal strategies. Aimed at professionals and graduate students in Polymer (plastic) industry, wastewater treatment plants, food industry, biodiesel industry, this set: Presents comprehensive and holistic consideration of these microbial bioplastics in the volumes. Enables reader to learn about microbiological, enzymatic, genetic, synthetic biology, and metabolic aspects of PHA biosynthesis based on the latest scientific discoveries. Discusses design and operate a PHA production plant. Strong focus on post-synthetic modification, preparation of functional PHA and follow-up products, and PHA processing. Covers all related engineering considerations