Fumigable warehouses: design and construction (NRI Bulletin 53)

In any grain storage system the control of insects is of paramount importance. The ultimate means of insect control is fumigation. Generally grain is fumigated by covering with a gas-proof fumigation sheet and using either methyl bromide or phosphine. An alternative to sheeting that is becoming increasingly popular is whole store fumigation. Such fumigations will only be successful if the warehouse is properly sealed and the fumigant gas concentration held at the appropriate level for a sufficient time to be lethal to insect pests. Warehouses of conventional construction can be made fumigable by attention to materials and design. Particular attention is needed to ensure that the roof and walls and their junctions are impermeable to gas. In this bulletin good design principles are specified and guidance is given on various materials used in the construction of fumigable warehouses. Procedures for carrying out successful fumigations are described

A mathematical model, with cost implications, for predicting temperatures in seed stores (ODNRI Bulletin No. 16)

Mathematical relationships are derived between climatic and design factors in seed stores using heat balance equations modified for tropical seed storage. A computer program has been written for the Hewlett Packard 9645 to make calculation easy; this incorporates data banks of the required parameters for common store building materials and for typical tropical climates. This program has been partially verified for grain in Sri Lanka using field data. Results from program case studies highlight the relative importance of different elements of warehouse design. For seed stores, the program employs viability equations to provide least-cost combinations of warehouse cladding and seed drying regimes under varying conditions of climate and building design. In a typical 1,000-tonne seed store use of aluminium roofing and concrete block walls instead of corrugated steel cladding can save over £12,000 a year, if both drying costs and annualized building costs are taken into account

The physical effects of tropical seasons on bagstacks of grain (ODNRI Bulletin No. 21)

Moisture diffusion into stacks of grain in sacks in tropical climates was studied. Wheat was used for a laboratory trial in simulated humid conditions, and millet and milled rice stacks were examined in warehouses in savannah and hot humid climates respectively. The measured moisture ingress profiles generally agreed with the predictions of a theory of isothermal moisture diffusion

An evaluation of structures suitable for emergency storage in tropical countries (ODNRI Bulletin No. 10)

The bulletin provides technical, economic and managerial assessment of emergency storage systems. It is based on investigations conducted by ODNRI and on information provided by users from the World Food Programme and five relief agencies. Where the priority was provision of food shelters quickly and easily, with facilities for rapid relocation, users favoured a combination of tarpaulins, tents and plastic-covered metal frame structures . Where the priority was security/ease of management, traditional warehouses or frameless modular structures were superior, more permanent and had a lower annual cost after four years of use. In either case if stores could be provided locally this was generally preferable - for reasons of speed and economy - to provision of imported stores, of which there are a number of well-tested types. Part I of the bulletin provides background, research and tables showing operational comparisons, capital costs, procurement times, packed weights and annual costs for the main store types. Recommendations for research on design of stores capable of resisting tropical wind loads and on bumper crop storage are made. Part II summarizes the results in Part I and provides for users/donors/ governments: (a) a practical decision tree for choosing a store, (b) a method for calculating store capacity, and (c) a catalogue of suppliers giving product details for freight, costs and telex numbers. Suppliers of pallets are included

The physical effects of tropical humid seasons on bagstacks of grain

7.20Available from British Library Document Supply Centre- DSC:2674.72(ONDRI-B--21) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

A mathematical model, with cost implications, for predicting temperatures in seed stores

8.00Available from British Library Document Supply Centre- DSC:2674.72(ONDRI-B--16) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo