So far as the waste-metal—light scrap, tins, and other odds and ends of a metallic nature—is concerned this was formerly sold in the form of detinned compressed billets. Under the present contract this is delivered to the contractor in the condition in which it is received. But it is quite possible that, at some future date, there may be a reversion to the baling process which formerly obtained. In view of this fact it has been deemed advisable to bale a certain proportion of the recovered metal merely in order to maintain the hydraulic compressing plant in good working conditions. The practice is to separate and to classify metallic material under one or other of six headings—bright tins, galvanized metal, light iron (black), cast iron, enamelled ware, and burned tins respectively.
While the Cleansing Department hitherto has not devoted any attention to the recovery of garbage from the refuse for conversion into pig-food, it is possible that this issue may be undertaken at a future date. The authorities have the suggestion under serious consideration with a view to its adoption.
The clinker question commands the attention of the Glasgow authorities, as it does all other communities equipped with facilities for carrying out refuse destruction by incineration. But, so far as this city is concerned, the problem does not bristle with perplexity as is invariably the case. The residuum from the furnaces of the Corporation works is mechanically screened into five varying grades, to meet the requirements of contractors who find it eminently adapted to their particular needs. No difficulty has yet been experienced in regard to the disposal of this article, a ready sale always having prevailed for the stocks available.
That the reclamation of the utilitarian contents of the domestic dust-bin is distinctly remunerative to the Glasgow civic authorities is reflected from a perusal of the revenue derived from the recovery and disposal of the city’s refuse during the year ended May 31, 1918. The sales’ record is as follows:—
| Materials. | £ s. d. | $ |
|---|---|---|
| Waste-paper | 8,993 14 5 | 44,969 |
| Old tins, light iron, etc. | 2,684 17 9 | 13,425 |
| Clinker | 718 10 10 | 3,592 |
| Sundries | 72 14 5 | 363 |
| Total | £12,469 17 5 | $62,349 |
To the above total there remains to be added the revenue derived from the sale of the prepared manure, arising from the admixture of the finely-screened dust and excremental material. This realized £6,718 17s. 8d.—$33,594—bringing the grand total to £19,188 15s. 1d.—$95,943. In this return the cinders are totally ignored, but, seeing that they constitute a highly serviceable fuel, the saving in the coal-bill, which their use secured, should be taken into consideration.
It is necessary to explain that, inasmuch as the thorough separation of the material is only of recent date, previous operations having been confined to the recovery of paper, old metal and the preparation of the fertilizer as already mentioned, the item “Sundries” cannot extend any criterion as to the results now being recorded, nor of the revenue derived from the recovery and disposal of the additional articles.
The successful conversion of the volume of dust, comprising about 50 per cent. of the aggregate, into a marketable fertiliser, offers a satisfactory solution of a complex and perplexing problem. But when the dust is coarser and yet deficient in “bite” or gritty characteristic, its disposal is not so readily consummated because its possible applications are thereby severely narrowed down in number.
Speaking generally, the utilization of the fine dust may be said to present a vexatious question. While it forms an excellent ingredient for a compounded fertilizer, it is not a simple matter to discover an inexpensive, and preferably second, refuse constituent of approved manurial value with which to associate it. The majority of the ingredients advocated as complying with the desired requirement possess too high an independent fertilizing value for such an application. In itself the dust is of very low soil-feeding power, and so active investigation is being pursued in anticipation of the discovery of a satisfactory adjustment to this question.
Another enterprising illustration of what can be achieved with domestic, office and warehouse refuse, both organic and inorganic, is extended by the Port of Liverpool. Here, again, the developments to be recorded in this connection are not attributable to the war, although the last-named factor was responsible for the conduct of the reclamatory process upon a more intensive scale. Liverpool is somewhat peculiarly situated among the importing centres of the United Kingdom seeing that it is probably the largest distributing centre for American foodstuffs for this country. Consequently, as is only to be expected, very considerable quantities of food which have suffered such damage during transit or demurrage as to become unfit for human consumption have to be handled. Under the old régime all organic waste of this character was either consigned right away to the destructor, or was perfunctorially treated to be sold as manure. Neither science nor brains was displayed in its disposal. The shortest way out of the difficulty was accepted as being the most effective in the public interests. But Liverpool was not the only port to follow such summary practice. It was common to all ports of the country in greater or lesser degree. The public loses heavily from the observance of such deprecatory measures, especially when it is borne in mind that such traffic runs into tens of thousands of tons during the course of the year. But under pre-war conditions, owing to the plentitude of supplies and the wide distribution of the losses incurred, the financial effect was scarcely felt by the unit of the population.