Global trends of mineral pigments in paper

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Published: Friday, 27 June 2014

The digital age has seen the demand for coated paper decreasing in established markets while developing regions have shown growth. Ian Wilson and Larry Lai look at trends in paper and coated board, and what this means for mineral pigments like calcium carbonate, talc and kaolin.

By Ian Wilson, Larry Lai*

There are a large number of mineral pigments used in paper, including calcium carbonate (GCC and PCC), kaolin and talc. The digital age has seen the demand for coated paper decreasing in established markets (North America and Western Europe) and has shown growth in developing markets (Asia and South America). However, there has been significant growth in coated board for packaging that has been recognised by all regions leading to a major rethink by at least one major European paper producer.

Jouko Karvinen, CEO of Stora Enso, writing in Rethink 2013 states, “Where in the world is Stora Enso’s future? Stora Enso is on a journey transforming itself from a European pulp and paper company into a value-creating renewable company focussing on growth markets. The digital revolution and its impact on paper consumption is a significant driver in the change.”



Global paper and board market

In 2011, the global paper and board market (P&B) totalled 399m tonnes, of which Asia accounted for 43% as shown in Fig.1, while China accounted for 25%, increasing to 26% in 2012.

Five countries accounted for 60% of P&B output in 2011, with China (25%), the US (19%), Japan (7%), Germany (6%) and Canada (3%). Of the 399m tonnes of P&B produced in 2011, the split by type was printing/writing paper (28%), packaging/paper board (53%), newsprint (8%), tissue (7%) and others (4%).



Regional and global trends in paper pigments Fillers

Global trends from 1972-2001 have seen a dramatic decline in the use of kaolin as a filler, being mainly replaced by calcium carbonate (PCC and GCC). Filler pigments utilised in 1972 in North America (mainly the US) were kaolin 92%, PCC 6%, GCC 1% and talc 1%. With the onset of satellite PCC plants, mainly by Specialty Minerals Inc.,a wholly owned subsidiary of Minerals Technologies Inc., as well as lime from limestone being readily available, the use of PCC fillers increased rapidly; 13% in 1988, 62% in 1996 and 63% in 2001. This resulted in a decrease in the use of kaolin from 92% in 1972 to 82% in 1988, 33% in 1996 and 20% by 2001.

While limestone sources for lime are widespread in the US, marble for GCC is limited geographically with GCC increasing from 1% of the market in 1972 to 14% in 2001. Only 1-3% of talc was utilised in North America from 1972-2001. The supply of PCC in North America has been dominated by Specialty Minerals Inc., with OMYA and Imerys being the major suppliers of GCC. Kaolin continues to be produced in Georgia, US.

The trend in Western Europe from 1972-2001 was different from the US in that calcium carbonate sources (marble, limestone and chalk) are widespread. There are also extensive talc deposits, particularly in Scandinavia, supplying fillers to the paper industry. In 1972, the filler market was made up of 80% kaolin, decreasing to 58% in 1988, 42% in 1996 and 33% in 2001. Kaolin was gradually replaced by GCC; 3% in 1972, 30% in 1988, 38% in 1996 and 37% by 2001. The use of PCC increased from 5% in 1972 to 26% in 2001. Talc showed a decline in use from 12% in 1972 to 4% in 2001.



Coating

North America (mainly the US) produces coating clay from Georgia from suppliers including Imerys, KaMin, BASF and Thiele, with kaolin accounting for 96% of the market in 1972, 92% in 1988, 80% in 1996 and 71% in 2001. As GCC entered the market, mainly produced from marble deposits in Alabama, Vermont and Canada, there has been a steady increase in its use; 6% in 1988, 14% in 1996 and 25% in 2001.

In Western Europe, kaolin was the main coating pigment used; 94% in 1972, 59% in 1988, 47% in 1996 and 34% in 2001. Kaolin has almost entirely been replaced by GCC (ground calcium carbonate), mainly supplied by OMYA and English China Clays (ECCI). In 1972, GCC use stood at 4% increasing to 39% in 1988, 48% in 1996 and 62% by 2001.

CEPI (Confederation of European Paper Industry) figures show (Fig.3) that from 1991 to 2012 the use of kaolin and calcium carbonate (GCC and PCC) for both filler and coating use increased from 8.0 - 12.8m tonnes, with kaolin remaining much the same at 4m tonnes. Whilst the use of kaolin has remained the same, calcium carbonate use (both GCC and PCC) has more than doubled from 4-8.8m tonnes. In 1991, the split was 50% kaolin: 50% calcium carbonate (GCC and PCC) and in 2012 the split was 30% kaolin: 70% calcium carbonate (GCC and PCC). The highest figures were in 2007 with 13.5m tonnes; 4.1m tonnes kaolin (30%) and 9.4m tonnes calcium carbonate (70%).



The situation in China Output decreases in 2013

RISI Global figures for 2013 are not announced until September 2014. However, Chinese production and consumption figures for 2013 will be made available by July 2014 in the China Paper Industry’s 2013 Annual Report. Following decades of steady growth of around 8-9% per annum, the figures for 2013 show a drop in production from 102.5m tonnes in 2012 to 101.1m tonnes in 2013, a decrease of 1.37%. Consumption figures also dropped from 100.48m tonnes in 2012 to 97.82m tonnes in 2013, a decrease of 2.65%.

The growth of production and consumption from 2004-2012 in China is shown in Fig.2. From 2007, production in China exceeded consumption figures and this has remained the situation up to 2013.

Paper pigments use in China

Approximately 20 years ago, some Chinese paper companies were importing chalk-based GCC from the UK and France. Today China is generally self-sufficient with its own production of GCC, and some PCC, for both coating and fillers. Any coating clay sourced from outside of China is now generally imported from Brazil and the US with a modest domestic supply from Maoming, Guangdong province. The estimated levels of GCC, PCC and kaolin used in paper in China are 12.3m tonnes in 2013 (Table 1).

The estimated production of GCC for paper is 11.2m tonnes, mainly produced by in-house GCC plants at paper mills with some slurry supplied by OMYA and Imerys, amongst others (Fig.4). The GCC is produced using marble from a number of deposits in China.

Global use of GCC, PCC, kaolin and talc used in P&B in 2013

During 2013, it was estimated that 48m tonnes of GCC, PCC, kaolin and talc was used globally in P&B, with 29.5m tonnes of coating (61% of total) and 18.5m tonnes of filler (39% of total). The split of GCC, PCC, kaolin and talc is shown in Table 2 on the basis of tonnage, and in Table 3 as percentages. Overall the 48m tonnes is dominated by GCC (65%), followed by kaolin (18%), PCC (13%) and talc (4%). For coating, the split is GCC (71%), kaolin (24%), PCC (3%) and talc (2%). Filler is dominated by calcium carbonate at 83% (54% GCC and 29% PCC), kaolin (10%) and talc (7%).

Increasing pigment use in CWF and UWF paper

With the high cost of pulp, the aim has been to increase mineral loading in paper and therefore reduce overall costs. For coated woodfree (CWF) the mineral loading (mainly calcium carbonate and kaolin) increased from 35% in 1980 and reaching 47% by 2010. The overall objective is to reach 51% by 2020 (Fig.5). For uncoated woodfree (UWF) the mineral loading is mainly calcium carbonate (GCC and PCC) with a clear aim to achieve 42% loading by 2020.

UWF paper accounts for 50% of printing and writing paper production globally with calcium carbonate (PCC and GCC) being the main filler used. The global trend is to blend PCC and GCC fillers in UWF papers as they are of a similar particle size. To achieve the required balance of paper properties required, blends of GCC with scalenohedral or aragonitic PCC provide a combination of bulk optics, stiffness and strength with efficient dewatering.

Scalenohedral or aragonitic PCC gives a higher light scattering and bulk compared to GCC or rhombic PCC. Scalenohedral and aragonitic PCC provide good optics, bulk and surface smoothness, whereas rhombic PCC or GCC give better strength and dewatering.

Kaolin consolidation continues

Global consolidation in the kaolin market has continued since 2008 (Table 4), with Imerys now controlling PPSA (purchased from Vale) as well as recently completing the acquisition of Goonvean.

In southwest England Sibelco now controls the kaolin deposits in Devon (Lee Moor) and Imerys controls all kaolin deposits and operations in Cornwall.

Thiele, in the US, and AKW, in Germany, are the only two companies that remain intact as principal producers of kaolin since 1980. Thiele is a leading producer of hydrous and calcined clay in Georgia (US) and purchased the 40.24% held by paper group Stora Enso for $76m in February 2014.

AKW (Quartzwerke Group), with operations in Germany, is now involved in the development of the Ukrainian Kaolin Company (Glukhovetsky kaolin plant) and in July 2013 gained control of 95.33% of the capital of Kaolin AD of Bulgaria. KaMin now control the Cadam deposit and plant acquired from Vale.

Coating clay production from the US, the UK and Brazil from 1974 to 2013 is shown in Fig.6.

In 1974, coating clay production from the US (Georgia) was 2m tonnes and 1m tonnes from the UK (Cornwall). Small amounts were produced in Brazil in the late 1970s from Cadam, with further amounts produced from the development of the Rio Capim deposits (PPSA and RCC) in the 1990s, giving a total production of around 3.1m tonnes by 2013. The US reached a peak of 6.3m tonnes in 1998, levelling off at around 3.2m tonnes by 2013. With the introduction of higher quality coating clay from Brazil, Imerys decided to cease production of coating clay from the UK in 2007.

There are other producers of coating clay that include AKW, English Indian Clays, Ukraine and Maoming in China. The development of high brightness coating clays from Western Australia is still being considered for the Chinese market.

*Ian Wilson is a consultant based in the UK and Larry Lai is president of the Yie-Lie Enterprise in China