With China posing determined new competition, Japan’s shipbuilding industry is intent on maintaining pre-eminence in the niche sector of woodchip carrier construction, writes David Tinsley.
Primarily serving as a raw material for the paper industry in Japan and China, but increasingly in demand as biomass for energy generation, woodchips constitute a growing sector of bulk cargo transportation. A distinct class of vessel originated in Japan has long characterised the trade in the Asia Pacific market.
Chip carriers have a much higher ratio of cubic storage capacity to deadweight compared to standard bulkers, due to the low density of the cargo. This necessitates much larger hold volumes, resulting in deeper hull sides, than conventional bulkers in the same deadweight class.
Ships are typically configured with six holds, providing a total capacity of in the range of 3.6 to 4.3 million ft3, and up to 4.7-5.0 million ft3 in the case of a new generation of Chinese-built tonnage. One of the holds can be used as a water ballast tank during unladen voyages.
Dedicated, purpose-designed woodchip carriers of the major, Japanese-controlled fleets are fully self-sustaining. Cargo systems comprise high-speed deck cranes, interposing hoppers, and belt conveyors, ensuring continuous unloading and rapid turnaround times. Chip unloading rates are in the order of 1,000t per hour. The underdeck spaces are accessed and closed by way of end-folding hatch covers, with the hatch openings maximised to facilitate cargo working.
The latest Japanese-owned and -operated vessels are built to within 210 metres length overall, ensuring flexibility with regard to Japanese discharge berths. Cargo volume gains have been achieved principally by extending the beam to some 37m from the earlier Panama Canal constraint of 32.2m.
A single two-stroke diesel provides the propulsion power, but the substantial electrical load involved with such vessels, a factor of the mechanical intensity constituted by the self-reliant cargo handling arrangements, can necessitate four large generator sets.
The global trade in woodchips has seen a marked development over the past 15 years, at an average growth rate of about 4% annually. Suppliers, buyers and carriers involved in the international woodchip trade use a common unit of measurement, the ‘bone dry metric tonne’ (BDMT), signifying a 0% moisture content.
Liftings increased to 36.3 million BDMT in 2018, according to analyst Hawkins Wright. Over 90% of the trade is generated by the paper and board manufacturing industries, particularly in Japan and China. With the planned expansion of pulp production capacity in China, the latter is likely to consolidate its recently gained top slot as the world’s largest importer of chips.
There is also a growing requirement for chips to be used in power generation, as countries seek to raise the share of renewables in the energy mix.
Imports of woodchips for the energy sector have increased sharply in Japan and South Korea, and biomass plant construction looks set to give further impetus to shipping demand. When combusted, biomass releases CO2, which is in turn absorbed by plants and trees, a cycle which leads biomass to be considered as carbon-neutral. As well as constituting a carbon-neutral fuelling solution, the biomass energy option also offers stable, uninterrupted baseload power, which can be a challenge with other renewable energy sources, notably that dependant on wind strength and continuity.
Japan has been importing woodchips in bulk carriers since the mid 1960s, while China’s trade began towards the end of 2002, with other countries entering the sector as buyers in much more recent times. Purpose-designed woodchip carriers have traditionally been the domain of Japanese companies, with NYK Line and Mitsui OSK Lines (MOL) commanding the largest fleets. Notwithstanding continued reinvestment by the major players, a more diverse ownership profile now pertains, contributory to which has been the emergence of Singapore-based Nova Carriers in the top echelon of the sector.
Japanese shipbuilders, notably Sanoyas and Oshima, provided all dedicated tonnage for a long period, but the past few years have seen the entry of Chinese yards into the field with alternative designs of geared and gearless, high-volume bulkers. Nova Carriers gave a huge fillip to the Chinese production by ordering 12 vessels from Nantong Minde and Jiangsu Yangzijiang.
The South East Asian region, especially Vietnam, Thailand and Indonesia, had long accounted for the highest proportion of supply to Asian markets, but developments in the woodchip carrier fleet, offering further scale economies, have helped drive increased purchases from Australia and other Southern Hemisphere sources such as Chile and South Africa.
An advanced class of 60,000dwt newbuild booked with Oshima Shipbuilding for deployment by NYK Line attests to the sustained high profile Japanese presence in this niche sector of bulk shipping.
Ordered on the strength of a long-term commitment by Mitsubishi Paper Mills, Oshima’s new-generation chip carrier will provide a transportation volume of 4.3 million ft3 within main dimensions of approximately 210m by 37m breadth. NYK has indicated that the prospective fleet entrant, due in 2021, will steal a march on other vessels through “considerably” lower fuel consumption, a low-resistance hull form promising improved performance in poor weather conditions, and an eco-friendly specification that includes an exhaust gas cleaning system.
The refined design combines Oshima’s know-how as one of the world’s most prolific builders of bulkships with NYK Line’s long track record as an owner and operator of dedicated, purpose-designed woodchip carriers, over 40 of which are currently in service. The newbuild will lead a batch production programme. NYK’s trading link with Mitsubishi Paper Mills is well established, and is currently expressed in four long-term contracts, said to be the largest share of such business held by any shipping company with the paper maker.
Modernisation of the NYK fleet in recent years has included the 60,360dwt Snow Camellia, brought into service during September 2018 under long-term contract to Hokuetsu Corporation (formerly Hokuetsu Kishu Paper). Constructed at Oshima’s Saikai (Nagasaki) yard to similar main dimensions as those of the latest newbuild series ordered there by NYK, the 4.3 million ft3-capacity vessel was assigned to the transportation of imported woodchips to the Hokuetsu paper mill in Niigata prefecture.
Shipments for Hokuetsu are also the remit of the MOL-operated, 60,300dwt Southern Treasure, the second of a new class of 4.3 million ft3 woodchip carrier turned out by Oshima last year. The vessel is powered by a 7,430kW 6UEC50LSH two-stroke diesel from Japan Engine Corporation (J-ENG), and is fitted with a scrubber.
She incorporates a raft of Oshima-developed hull form elements, notably the Seaworthy Bow, designed for better speed keeping in adverse weather, proprietary rudder fin, and advanced flipper fins aft, plus propeller boss cap fins (PBCF), an energy-saving solution devised by a Japanese partnership that included MOL. The electric deck cranes are fitted with a regenerative power system, whereby energy is recovered for the ship’s net during the lowering process.
Supplies of woodchips to the Hokuetsu mills in Japan are made from Vietnam and various sources in the southern hemisphere, mainly Chile, South Africa and Australia.
The changing profile of the Japanese trade is reflected in a newbuild scheme implemented by K Line on the strength of a charter agreement with Nippon Paper Industries. The vessel will transport both raw material woodchips used in paper and board making and also ‘energy’ woodchips for biomass power generation. In the latter case, the recipient will be Nippon Paper’s Tomakomai biomass plant, which is due to start operations in 2023.
While the chosen shipbuilder has yet to be announced, contractual terms stipulate delivery of the vessel before the end of 2022. The specification includes a scrubber, and the raft of energy-saving elements features a hybrid fin fitted immediately abaft the propeller.
Reinvestment in woodchip carrier capacity by K Line in recent years has entailed the 3.6 million ft3 Forestal Gaia, commissioned from Tsuneishi Shipbuilding in May 2017. The 49,200dwt vessel cut her teeth on shipments from Vietnam, conveyed on behalf of Nippon Paper.
Sanoyas Shipbuilding Corporation has delivered over 50 woodchip carriers to date, and has recently developed an LNG-fuelled design based on a 4.3 million ft3-capacity vessel template. ClassNK has issued an approval in principle (AIP) for the concept, which promises a 40%-plus improvement in Energy Efficiency Design Index (EEDI) rating. The LNG fuel tank will be mounted on the open, flush stern deck abaft the superstructure, obviating loss of underdeck revenue-earning volume.
Current industrial developments that will create new transportation requirements include the construction in Ibaraki prefecture, north of Tokyo, of the 50MW Kamisu biomass plant, which will use palm kernel shells (PKS) and wood pellets as feedstock. GE has been contracted by industrial group Hitachi Zosen Corporation to supply key power components for the facility, due to start operations in 2023.
GE’s delivery will include a reheat steam turbine generator and low-NOx circulating fluidised bed(CFB) boiler. The latter type of machinery figures increasingly in Japanese biomass power schemes, since CFB technology allows for flexibility in the type of biomass fuels that can be used, be it woodchips, wood pellets, or PKS. The abundance and comparatively low cost of PKS, a waste product of the palm oil industry, in South East Asia could promote increased use in Japan’s biomass mix over the coming years, assuming suppliers can meet regulatory requirements as to sustainability.
Last December, Mitsubishi Corporation launched a biomass power generation project at Fuji City, Shizuoka Prefecture, in conjunction with Nippon Paper Industries and Chubu Electric Power, using wood pellets.