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Gas Release (gas + release)

Distribution by Scientific Domains
Chemistry80%

Selected Abstracts

A Descriptive Model for the Kinetics of Gas Release in Different Types of Pizzas

JOURNAL OF FOOD SCIENCE, Issue 3 2003
M.L. Cabo
ABSTRACT: A model based on typical equations of microbial kinetics is proposed to describe gas release (GR) in ham, tuna, and meat pizzas packaged under different CO2 -enriched atmospheres: 20% CO2, 70% CO2, and 70% CO2 plus 500 mg/kg Nisaplin. CO2 -enriched atmospheres hardly influenced LAB growth but reduced GR, which points to the importance of yeasts for GR. Nonetheless, LAB also contributed significantly to GR, so Nisaplin also delayed GR. Gas release followed a diauxic pattern, the 2nd stage being presumably related to yeasts shifting from respiratory to fermentative metabolism once oxygen was depleted. However, storing pizzas for longer than 25 to 30 d does not seem appropriate in terms of shelf life, so the model proposed appears adequate for practical purposes. [source]

Safety evaluation of sewage-sludge-derived fuels by comparison with other fuels

FIRE AND MATERIALS, Issue 4 2009
Xin-Rui Li
Abstract The utility of sewage sludge as a biomass fuel is taken as a new approach to recycle unwanted wastes as renewable energy and deal with global warming. However, safety caring of this new type of fuel is a premise before it is practically used in boilers. Thermal behaviors of four sludge-derived fuels which are under development were examined by several calorimeters (such as thermogravimetry/differential thermal analysis, C80 and thermal activity monitor) at temperature ramp and isothermal conditions. Heat generation at relatively low temperatures was observed. The corresponding spontaneous ignition was detected in an adiabatic spontaneous ignition tester at 80,C in some sludge species. Moreover, a certain amount of gaseous evolution was accompanied when the sludge fuels were stored at room temperature and at 60,C. Oxidation is mainly responsible for the heat and gas release from the sludge fuels. The hazards of the sewage sludge fuels were also compared with a bituminous coal and a refuse-derived fuel, which have the main feature of spontaneous ignition. Copyright © 2009 John Wiley & Sons, Ltd. [source]

A Descriptive Model for the Kinetics of Gas Release in Different Types of Pizzas

JOURNAL OF FOOD SCIENCE, Issue 3 2003
M.L. Cabo
ABSTRACT: A model based on typical equations of microbial kinetics is proposed to describe gas release (GR) in ham, tuna, and meat pizzas packaged under different CO2 -enriched atmospheres: 20% CO2, 70% CO2, and 70% CO2 plus 500 mg/kg Nisaplin. CO2 -enriched atmospheres hardly influenced LAB growth but reduced GR, which points to the importance of yeasts for GR. Nonetheless, LAB also contributed significantly to GR, so Nisaplin also delayed GR. Gas release followed a diauxic pattern, the 2nd stage being presumably related to yeasts shifting from respiratory to fermentative metabolism once oxygen was depleted. However, storing pizzas for longer than 25 to 30 d does not seem appropriate in terms of shelf life, so the model proposed appears adequate for practical purposes. [source]

Toxic gas release caused by the thermal decomposition of a bulk powder blend containing sodium dichloroisocyanurate

PROCESS SAFETY PROGRESS, Issue 2 2003
Andrew R. Carpenter P.E.
A thermal runaway reaction occurred during the mixing of a batch of a bulk powder that resulted in the production and release of toxic gases. The mixture consisted of an oxidizer (sodium dichloroisocyanurate), some organic compounds, and inert compounds. This toxic release led to the evacuation of the building and resulted in extensive damage to the facility. This was only the fourth time an 1,100-pound batch of this material had been mixed in this equipment. Prior to this production run, the material had been prepared in small batches of 2 to 50 kilograms. Accelerated Rate Calorimetry (ARC) testing had been performed prior to the scale-up to production batches. This paper looks into the root causes of this particular accident and demonstrates how proper analysis of the testing data and other warning signs observed during the bench testing could have revealed the likelihood of this accident. Further, this paper will consider how simple design changes to the manufacturing process resulted in an inherently safer design. [source]