Introduction

'Naval stores' is the inclusive term used to denote the products obtained from the oleoresin or resin* of pine trees (genus Pinus). The term originates from the days when wooden sailing ships, including naval ships, were waterproofed using pitch and tar and other resinous products from pine trees. Although the connection with s hips is now remote, the term is still commonly used by those in the trade and elsewhere. There are three distinct sources of naval stores:

Gum naval stores are obtained by the tapping of living pine trees. Collection of the 'gum' or resin is a labour-intensive operation (similar to rubber tapping). Distillation of the resin, which can be undertaken in fairly simple equipment, produces gum rosin and gum turpentine in varying ratios, usually between 4:1 and 6:1.

Sulphate naval stores are by-products recovered during the conversion of pine wood chips to pulp by the sulphate (kraft) pulping process. Sulphate turpentine is condensed from the cooking vapours. Crude tall oil, obtained from the alkaline liquors, is fractionated into various products including tall oil rosin and tall oil fatty acids.

Wood naval stores are obtained from resin-saturated pine stumps long after the tree has been felled. The stumps are solvent extracted using capital intensive technology to give wood turpentine, wood rosin, dipentene and natural pine oil.

* The terms 'oleoresin' and 'resin' may be used interchangeably, and for convenience the term 'resin', which must not be confused with rosin, is used in this report. Standard terminology relating to naval stores is given in the American Society for Testing and Materials (ASTM) standard D 804-92.

Pinus is one of the most widely distributed genera of trees in the northern hemisphere, extending from the polar region to the tropics; one species, P. merkusii, occurs naturally south of the Equator. The genus is also one of the most widely planted exotics because of its large-scale use for timber and pulp, and large areas of Pinus are found outside its natural range in South America, Africa and Australasia. Standing resources of pine trees exist, therefore, in many parts of the world.

The two major products of the naval stores industry are rosin (a brittle, transparent, glossy, faintly aromatic solid) and turpentine (a clear liquid with a pungent odour and bitter taste). Annual world production of gum rosin and gum turpentine is approximately 700000 tonnes (valued at around US$ 420 million at first half 1994 prices) and 100000 tonnes (valued at US$ 50 million), respectively. For many years rosin and turpentine were used in an unprocessed form in the soap, paper, paint and varnish industries. Today, most rosin is modified and used in a wide range of products including paper size, adhesives, printing inks, rubber compounds and surface coatings. The composition of turpentine can vary considerably according to the species of pine exploited, and this greatly influences its value and end use. Turpentine, like rosin, is a very versatile material and nowadays is used mainly as a feed stock by the world's chemical industries. The alpha- and beta-pinene constituents of turpentine, in particular, are the starting materials for the synthesis of a wide range of fragrances, flavours, vitamins and polyterpene resins, and form the basis of a substantial and growing chemical industry. However, the simpler, more traditional products in which rosin and turpentine can be used, such as soap, paper size and paints and varnishes, can still be of value to the domestic economy of developing countries, and it is not necessary to think only in teens of the wider international markets when planning naval stores production. Consumer demand in developing countries is expected to grow with increasing industrialization and urbanization and there are, therefore, opportunities for countries with suitable pine resources to replace imported naval stores products with those produced locally.

The aim of this publication is to provide basic information to enable prospective new producers of gum turpentine and gum rosin to make considered judgements on whether or not to proceed with investment. Information on the production of wood and sulphate naval stores, and on further processing of gum rosin and gum turpentine, is not included. The publication is intended particularly for prospective producers and government bodies, financial institutions or donor agencies in developing countries concerned with the appraisal of projects involving gum naval stores production. It is hoped, also, that it will assist existing producers, traders and consumers of gum turpentine and rosin by increasing their awareness of production methods and product characteristics in other parts of the world, and their knowledge of market demands, trends and preferences.

The text is presented in five chapters. Following this introduction, Chapter 1 summarizes major aspects of production, trade and markets for gum naval stores. The chief pine species used in different parts of the world are listed, and the levels of production and trends in all the major producing countries are indicated. Chapter 2 reviews the tapping methods used to recover resin from the free, and in Chapter 3 the technology required to process the resin into rosin and turpentine is described. In Chapter 4, the financial and economic aspects of the resin tapping and processing operations are analysed. In the final chapter, the technical and economic aspects which must be considered when planning a gum naval stores industry are summarised. The appendices contain references and suggested further reading, quality criteria, specifications and test methods for rosin and turpentine, a discussion of genetic factors influencing resin composition and yields and the importance of correct species and provenance selection when assessing pine trees for tapping, packaging requirements for turpentine and rosin, a list of importers and traders of naval stores, and statistical tables.