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

China's ammonium bicarbonate industry

Summary

Ammonium bicarbonate (ABC) was once the mainstay of China's nitrogenous fertilizer industry. It suffered a long and slow decline during the 1990s, and was expected to be phased out altogether. But ABC is proving to have a longer life than many suspected.

Abstract

Like most nitrogen fertilizer consumers during the 1950s, China had relied on ammonium sulphate from coke oven gas and ammonium nitrate from synthetic ammonia as its main fertilizers. However, these required expensive technology to produce, much of which had to be imported. Urea was known but the technology was still not fully developed and above all required stainless steel. In 1958, facing an urgent need for fertilizer nitrogen and a shortage of stainless steel, Peng Tao, the Minister for Chemical Industry, proposed a new strategic concept for Chinese nitrogen production based on a series of small fertilizer plants converting ammonia to ammonium bicarbonate (NH4HCO3). Dispersing small plants across the country overcame some of the infrastructural issues associated with transporting large volumes of fertilizer across China.
The initial plan was to use 10,000 t/a of mostly small-scale, coal-based ammonia capacity to produce 40,000 t/a of ABC using carbon dioxide from the ammonia tail gas. The ammonia was used as a wash to remove CO2 from dissolved solution, with ABC crystallising out. The process was simple and had a low investment cost, and was seen as an ideal solution for China’s fertilizer needs at the time. The process was further improved by Hou Debang and his research team, with the ammonia wash becoming a pre-treatment for the syngas feed from the gasifier.

Add to basket


Impressive plant performance at NFCL

Summary

Nagarjuna Fertilizers & Chemicals Limited (NFCL) has maximised its capacity utilisation and reduced its specific energy consumption, while adapting to changes in feedstock and adhering to government regulations. R. Raghavan and K.R.R. Kumar of NFCL discuss the effect of feedstock change on plant performance, the optimisation of process parameters and the staged revamp to attain maximum capacity utilisation. These schemes resulted in improved economics, with the energy saving schemes alone resulting in monetary savings of $3.643 million/year.

Abstract

Nagarjuna Group, established in 1973, is recognised as one of the most successful agricultural brands in India. The flagship company of the Nagarjuna Group, Nagarjuna Fertilizers and Chemicals Limited (NFCL),  is ranked amongst, the largest fertilizer companies in India with a market share of 2.119 million tonnes of urea (representing 10% of India’s annual consumption) and with a market share of 30% in speciality fertilizers, making NFCL the largest specialty fertilizer company in India.
NFCL operates a large, modern, integrated ammonia-urea complex with an annual capacity of 1.56 million tonnes of urea. The complex is laid out in two streams, located at Kakinada on the east coast of India in the state of Andhra Pradesh. The factory is surrounded by a green belt of more than 283 hectares of flora and fauna out of a total plant area of 456 hectares.

Add to basket


Hydrogen optimisation in refineries

Summary

Refiners are facing increasing demands on their hydrogen plants and distribution systems. At the National Petrochemical & Refiners Association Annual Meeting in San Antonio in March, several papers were presented dealing with these issues Nitrogen+Syngas presents a round-up of proposed solutions.

Abstract

Refiners are facing twin challenges in terms of having to process heavier and sourer feedstocks while reducing emissions of greenhouse gases, especially carbon dioxide. Hydrogen plant operation, use and integration is at the heart of these challenges, as measures to treat sour and/or heavy feedstocks often involve hydrogenation, and generating the hydrogen is often a source of greenhouse gases.


Hydrogen management in a GHG constrained refinery
The session’s first paper, by William Fairleigh of KBC Advanced Technologies, discussed various options for reducing CO2 emissions. With increasing incentives to reduce the emission of greenhouse gases, refineries and petrochemical plants face big challenges in their operation. A project in a North American refinery demonstrated that up to 15% emissions could be reduced with projects having a simple payback of three years or less. For regulatory compliance, and before embarking on any projects to reduce CO2 emissons, a carbon management program needs to be put in place.

Add to basket


Iran: caught between politics and economics

Summary

Iran continues to try and forge ahead with major petrochemical developments, driven by the compelling economics of its major offshore gas reserves. However, as always with Iran politics remains a complicating factor.

Abstract

In June last year the United Nations Security Council approved a new, tighter sanctions regime against Iran, due to continuing arguments over the country’s alleged development of a nuclear weapons programme in contravention of IAEA rules. A ratcheting up of US sanctions followed almost immediately, and the EU and Canada followed suit in July, with new restrictions on foreign trade, financial services and the oil and gas sectors – Iran’s lifeblood.


Economic troubles
In spite of the pressure caused by ongoing sanctions, Iran’s economy has been expanding for most of the past decade, and is currently ranked 18th in the world. Growth had been running above 6% up to about 2007, although it has apparently dipped sharply after the global economic crash to 2.5% in 2008, 1.5% in 2009 and only recovered to between 1 and 3% in 2010, according to ‘best guess’ estimates. Because the country has a young and rapidly growing population, it is estimated that there are 750,000 new entrants into the employment market every year, which would in theory require a growth rate of at least 5% to absorb them, and the worsening economy and relatively high unemployment rate (estimated at 14% in 2010) has been one of the factors behind recent unrest in the country.

Add to basket


Plant Manager+

Summary

Problem No. 6 Choking of urea fluid bed granulator nozzles The nozzles used in urea fluid bed granulation form the most essential part of a fluid bed granulation plant. Each licensor has developed its own specific nozzles and its features have a significant impact on the performance and efficiency of the granulation plant. Common to all nozzles is the mixing of urea melt with air although in which way the mixing is taking place differs widely between the different technologies. In Uhde Fertilizer Technology's fluid bed granulation, the nozzle produces tiny droplets which solidify and join the seed material by an accretion process leading to a very hard granule. Stamicarbon's fluid bed nozzle produces a layer of urea melt, which solidifies on the seed material forming an "onion" kind of granule leading to a very spherical shape. In Toyo Engineering Corporation's fluid bed granulator each nozzle forms a spouted bed, where vigorous mixing occurs, leading to round, uniform granules. Urea Casale applies a nozzle, which generates very fine droplets due to the fact that in the nozzle an emulsion of urea melt and air is formed, which is sprayed out of the nozzle. The very fine urea melt droplets make it possible to apply a urea melt feed with a higher water content to the granulator as the water is able to evaporate from the fine droplets. This round table discussion discusses the problem of nozzle choking: What are the causes and solutions? From several rounds of questions and answers the problem area and a most likely root cause has been identified, which could solve the problem for urea producers.

Abstract

Mr Saadat Motamedi of Operations at Pardis Petrochemical Company in Iran introduces to the round tables his problem with choking fluid bed urea granulation nozzles (see photo) and asks:
What do you think is the cause of the choking as shown in the picture? Is it from the urea melt or atomisation air stream and why?

Mr Prabhat Srivastava of TATA Chemical Limited in India replies: Seeing your pictures it is my assumption that it may be possible that a particular nozzle gets partially choked and the urea melt/air mixture could not exit with the desired velocity.

 

Add to basket


The chemistry within your catalysts - Part 2: Steam reforming

Summary

Despite the maturity of the technology, steam reforming continues to be one of the most challenging duties in the syngas plant flowsheet. Design of steam reforming catalysts to withstand the process conditions that are becoming ever more arduous requires expertise, state of the art research infrastructure and a knowledge base of years of experience. This article by P.V. Broadhurst, S. French, F. E. Lynch and M. Nijemeisland of Johnson Matthey Catalysts discusses the role of steam reforming used in the manufacture of ammonia, methanol and hydrogen and how understanding the chemistry of the catalysts used in this process is fundamental to reliable and efficient operation of these process plants.

Abstract

As far back as the early 1900s, scientists were attempting to fix nitrogen and manufacture fertilizers for food production. When the Haber Bosch process for ammonia production was developed in 1917, hydrogen for the process was produced by reacting steam with coke. However, even as early as the 1920s, interest was centred on how the steam reforming of methane could be used to produce a more economic source of hydrogen. Hydrogen was first produced using the steam reforming process in Baton Rouge in 1931. However, it was not until the 1950s that the ability to run at pressure allowed the process to become the ubiquitous method of producing syngas from hydrocarbon feeds.
Today, steam reforming is at the heart of the processes used to manufacture ammonia, methanol and hydrogen, known as synthesis gas or syngas plants. The catalyst in the reformer has a direct impact on the plant rate, reformer tube life, methane slip and the risk of carbon formation, which can have a significant and detrimental impact on the reformer performance and operation. Improvements in the catalysts can help to extend the operating envelope in areas such as plant rate, run length, operating severity and resistance to plant upsets.

Add to basket


Methanol market update

Summary

China continues to set the tone of the global methanol market

Abstract

The past 10 years have been boom times for the global methanol industry, with both demand and capacity more than doubling. Much of this has been down to the massive growth of the industry in China, both for conventional chemical production and for new uses such as fuel blending. Can methanol’s rapid growth continue to be sustained?

Demand
Demand for methanol continues to surge, averaging 7-10% per year, and has now reach 46.5 million t/a according to CMAI. Demand for methanol is these days divided between traditional, chemical derivatives like formaldehyde, acetic acid and methyl methacrylate, with demand running just above global GDP growth, at about 4% per annum, and the continuing emergence of fuel uses, which are growing at a remarkable 13% per year. Methanol blending into gasoline in China has been one of the biggest success stories, although as with ethanol in the US, that market is approaching a ‘blend wall’ of 10%, beyond which it can only penetrate in specially designed vehicles. Nevertheless, China now represents almost half of methanol demand, and is projected to represent the majority of methanol demand somewhere between 2013 and 2016.

Add to basket


Tried, tested and proven

Summary

New syngas catalysts offer increased benefits. In this article we report on new feed purification products, which are essential for protecting downstream catalysts from sulphur poisoning; we provide an update on a new methanol synthesis catalyst that is delivering enhanced benefits; and we report on industry experiences with a particularly robust HTS shift catalyst, which has proven to be able to withstand even severe waste heat boiler leaks.

Abstract

Add to basket