BC Insight - Nitrogen+Syngas, Sulphur, Fertilizer International
Login
BCInsight Ltd
China Works
Black Prince Road
London, SE1 7SJ
United Kingdom
Tel: +44 (0)20 7793 2567
Fax: +44 (0)20 7793 2577

Publication > Issue > Articles

ASRL Review

Summary

Sulphur deposition and production of sour gas: background, prediction and mitigation by Dr. Peter Clark, Director of Research, Alberta Sulphur Research Ltd

Abstract

Sour natural gas has been produced in the foothills of the Rocky Mountains in commercial quantities since the mid-1950’s. As most readers are aware, the excessive amounts of H2S found in the foothills gas has resulted in Canada being the world’s major producer of elemental sulphur for almost half a century. Countries in the Middle East and Kazakhstan are now threatening to take this somewhat unenviable title away as they too capitalise on large sour gas reserves. The goal of this article, in honour of having the Sulphur 2003 conference in Banff, Alberta, is to discuss some of the important issues connected to sour gas production as a result of the presence of small amounts of elemental sulphur found in this type of gas.

Despite being an old problem, the phenomenon of solid sulphur deposition in wells producing sour gas is a continuing thorn in the side of sour natural gas producers in western Canada. Some Canadian experience will quite possibly be of interest to those now contemplating sour gas production in other parts of the world.

Add to basket


Simulator provides better engineering design

Summary

Clausim is a powerful simulation tool developed for the design, analysis, optimisation and operation of SRUs. Additional benefits include its application for training purposes and online applications. Michael Kilian, product manager for Clausim at Siemens discusses the development, features and benefits of the new sulphur simulator.

Abstract

In order to meet these increased demands the industry has to find ways to increase the throughput of Claus units, improve sulphur recovery efficiencies and to install new facilities. This is often a cost factor for the refiners. Furthermore, the units must be very reliable with a high on-stream factor in order to avoid process upsets, shutdowns and outages of equipment.

Ever stricter environmental regulations are forcing industrialised countries to reduce the sulphur content of fuels. Sulphur reduction and worldwide regulations in refineries could prove to be one of the greatest challenges for the future. Under the Auto Oil II program, the European Community has decided to reduce the maximum allowable sulphur level in gasoline and diesel to less than 50 ppm beginning in 2005. Similar programs are intended in other industrial regions in the world. Some countries, e.g. Germany already produce sulphur free products (less than 10 ppm) because of financial incentives from the government.

Lower sulphur levels result in the liberation of more hydrogen sulphide in the hydrodesulphurization unit. This will undoubtedly increase the sulphur load to the Claus units. Secondly, worldwide the regulations for sulphur recovery efficiencies are becoming more stringent as a result of the demand to reduce SO2 stack emissions. And thirdly, there is a trend that the sulphur content of crude oil is slowly increasing. This can be explained by the fact that the number of deposits of crude oil with lower densities has been decreasing in recent years. For example, the average annual increase in the sulphur content of Japan’s imported crude oil is about 0.01% based on historical data over a 15-year period.

Add to basket


Better handling of acid plant effluents

Summary

Laboratory testing is a valuable tool to understanding the effect of contaminants in effluent streams on the lime neutralisation process. A. Stegmann and J.Thomson of Chemetics report on recent tests that have shown the effects of particular contaminants and pH on the settling rates and purity of the product gypsum.

Abstract

Metallurgical acid plants receive gas from smelters that is heavily contaminated with a number of solid and gaseous impurities. The performance of the acid plant is dependent on the performance of the gas cleaning section, which removes these impurities and produces a contaminated weak acid stream.Table 1 gives typical analyses of effluent streams from gas cleaning.

The most common means of dealing with the weak acid effluent is lime neutralisation. The advantage of this approach is that it is well established and uses relatively simple equipment. The process principle is that the majority of the contaminants in the acid can be precipitated as insoluble metal hydroxides and the acid precipitated as calcium sulphate (gypsum).

Add to basket


Facing the challenge of lower detection limits

Summary

As countries phase in ever lower permissible levels of total sulphur in fuels, the environmental monitoring and fuel manufacturing industries have been forced to find more sensitive techniques for analysis. Lisa Connock reports on Antek's new generation analysers, and Agilent Technologies' new method for determining both total sulphur and sulphur species at ultra low levels.

Abstract

Sulphur in motor fuels has been implicated as one of the contributing factors to global warming and acid rain. It is also a catalyst poison for automobile catalytic converters and refinery catalytic crackers. As a result, the trend in Europe and the US has been to progressively reduce the acceptable level of total sulphur in motor fuels. Refining, importing and fuel distribution industries already face strict regulatory hurdles for control of sulphur in reformulated gasoline (RFG) and diesel and these are set to become even more stringent as future sulphur specifications are expected to be lowered to “near zero” levels.

In December 2002, the European Union (EU) announced that new regulations would require full market availability of sulphur-free fuels, defined as containing less than 10 ppm sulphur content by January 1, 2005. The phase-in is to be complete by January 1, 2009. The EU also committed under the UN Kyoto protocol of 1997 that it would reduce emissions by 8% from 1990 levels by 2010.

Add to basket


Polysulphides chains of consequence

Summary

Poly-what? Never heard of it and, what's more, it sounds esoteric and unimportant? You couldn't be more wrong, says Jim Hyne of Hyjay Research & Development.. If it wasn't for hydrogen polysulphides, a whole lot of important things that happen when hydrogen sulphide is processed to produce elemental sulphur just wouldn't happen.

Abstract

‘Poly’ sulphur The atoms of the element sulphur have a propensity to “concatenate”. That means they like to attach to themselves in chains.Atoms of the element carbon do the same thing making possible the structures upon which life itself is based. The commonest manifestation of sulphur “concatenating” is the sulphur molecule itself: A nice chain of eight sulphur atoms that decided, for good thermodynamic reasons, that eight was enough, caught its own tail and became a crown shaped ring of eight sulphur atoms – cyclooctasulphur. (Fig. 1)

Although this is a closed ring rather than a long chain, “cyclo-octasulphur” is a genuine polysulphide and makes up by far the bulk of every drop of sulphur made, sold and consumed in the business.

Add to basket


Optimising metallurgical operations

Summary

Bioconversion of sulphur compounds using high rate biotechnology is finding a growing number of applications in the mining and metals industries. High rate biotechnology provides a clean, safe and effective system for metals recovery and solving environmental problems. This article highlights current and potential applications.

Abstract

The potential of integrating biotechnological processes in mining and metallurgical operations has gained a lot of recognition over the past years. Traditionally, biotechnology has mainly been used in mining for bioleaching purposes. Bioleaching is familiar to miners and metallurgists and there is a general acceptance of the potential of this approach. There are however several other biotechnologies that can be applied to advantage in this area and which are not as well known as bioleaching. This article will focus upon new, high rate bioconversion of sulphur compounds.

Add to basket