Entity

Time filter

Source Type

North Geelong, Australia

Turner D.A.,University of Melbourne | Edis R.B.,University of Melbourne | Chen D.,University of Melbourne | Freney J.R.,University of Melbourne | And 4 more authors.
Agriculture, Ecosystems and Environment | Year: 2010

This study conducted in the Wimmera, a major cropping area in western Victoria Australia, evaluated a backward Lagrangian stochastic (bLs) dispersion model for measuring ammonia (NH3) loss and compared NH3 losses from a wheat crop after top-dressing with urea or "Green Urea". Green Urea contained 45.8% nitrogen (N) as urea and "Agrotain" (N-(n-butyl) thiophosphorictriamide) @ 5.0 L/t. The two products (80 kg N ha-1) were applied to circular plots of 25 m radius and losses were determined for a period of 23 days using mass balance micrometeorological methods. When the NH3 concentration in the air at the stability independent height, 0.8 m above the crop, was used there was a strong relationship between the vertical flux density of NH3 as determined by the full profile method and that determined by the bLs method (r = 0.86). Rates of ammonia loss from the urea treatment ranged from 0.2 to 2.1 μg N m-2 s-1, while those from the Green Urea treatment never exceeded 0.35 μg N m-2 s-1. Cumulative NH3 losses for the urea and Green Urea treatments were 7.6 kg N ha-1 (9.5% of applied N) and 0.8 kg N ha-1 (1.0% of applied N), respectively. The results indicate that use of Green Urea instead of regular urea in Victorian wheat growing could substantially reduce NH3 emission. © 2010 Elsevier B.V. All rights reserved. Source


Balch K.,Dyno Nobel Inc. | Handford R.,Dyno Nobel Inc. | Pattabathula V.,Incitec Pivot Ltd. | Strepparola E.,Ammonia Casale
Ammonia Plant Safety and Related Facilities | Year: 2013

The Dyno Nobel ammonia plant at St Helens, Oregon, USA, has been in operation for more than 40 years. This plant is a 1960's vintage plant that operates at very high synloop pressures of up to 5000 psig. As the old axial flow path baskets were approaching end of life, Dyno Nobel decided to replace those baskets with a new design of Casale axial-radial baskets in all three vessels that were in series. Some issues related to mechanical integrity of the vessels and nozzles were noticed during replacement of the baskets and they are explained in this paper with a focus to help those plants in the industry that operate similar vintage plants. Source


Williams G.,PSI Inc. | Pattabathula V.,Incitec Pivot Ltd.
Ammonia Plant Safety and Related Facilities | Year: 2013

This year marks the centenary of the industrial production of ammonia, which was first carried out by BASF in Germany. The synthesis of ammonia from its elements was vital as the world without fertilizers could only sustain a population of around 4 billion people, rather than the almost seven billion we have today. Source


Angus J.F.,CSIRO | Angus J.F.,Charles Sturt University | Gupta V.V.S.R.,CSIRO | Pitson G.D.,Australian Department of Primary Industries and Fisheries | Good A.J.,Incitec Pivot Ltd.
Crop and Pasture Science | Year: 2014

Experiments conducted over three seasons in southern New South Wales tested the effects of concentrating anhydrous ammonia (AA) and urea fertiliser in bands occupying ∼3.5% of the topsoil volume. Yield responses to applied nitrogen (N) were small or negative in a drought but larger (17kg grain kg-1 N fertiliser) in favourable seasons. There was no consistent difference between AA and urea effects on yield, grain protein or efficiency of fertiliser-N recovery, and there were no consistent differences arising from banding depth or application time. Gaseous loss of ammonia to the atmosphere was negligible from urea granules or AA injected into the soil as gas or liquid. Soil ammonium concentration was >700gNg-1 in bands of ∼5cm diameter when measured 6 days after AA application but halved within 5 weeks due to nitrification. Within 1 day of banding AA or urea at sowing, pHwater in the bands rose from 6 to 8.5, leading to transient changes in microbial activity and populations. Immediately after banding, microbial biomass carbon and numbers of protozoa fell by about half, but numbers of ammonia-and nitrite-oxidisers were unchanged. Five weeks later, microbial biomass carbon and protozoa had partly recovered whereas numbers of ammonia-and nitrite-oxidisers increased 5-10-fold. After 7 months, there was a small reduction in microbial diversity in the bands, shown by analysis of fatty acid methyl esters. Seedling growth was slower where N fertiliser was applied in concentrated bands than when mixed throughout the topsoil, supporting previous research showing that roots avoid bands of highly concentrated ammonium. Banding thus provided a slow-release form of N to wheat crops, thereby reducing excessive seedling growth and the risks of haying-off. © 2014 CSIRO. Source


Pattabathula V.,Incitec Pivot Ltd.
Ammonia Plant Safety and Related Facilities | Year: 2014

This paper looks at some of the incidents that have occurred in ammonia plants and the hydrocarbon industry, and discusses the breakdowns in the safety management system which caused such incidents. The failures related to Start-up Override Switch/System, Process Override Switch/System and Maintenance Override Switch/System are essentially systematic failures and hence a robust audit and verification system is necessary to prevent these failures. A brief description of interlock configurations is included. This paper also discusses some of the nuances associated with the interlock configuration, immediate causes including scope creep and root causes of failures, practices currently undertaken in many of plants and new solutions. Source

Discover hidden collaborations