Modern Gasworks Practice

PLANNING AND LAYING OUT OF GASWORKS 23 If the works manufacture its own sulphate, it is advisable not to store am-moniacal liquor for too long, owing to evaporation and other losses. A general guide is 5 weeks’ (maximum) storage for tar and liquor. Sulphate Plant Assuming that sulphate is made ten or twelve times a year, the plant should have a capacity of 3-3| tons of sulphate per 24 hours for every million cubic feet of gas per maximum day. This allows for sulphate making during six days. If it is proposed to make at different periods, or for more or less days, the adjust-ments can. be made accordingly. This, of course, refers to the distinct plant for producing sulphate, but it has to be Borne in. mind that a few of the smaller works-are now employing the semi-direct method of recovery whereby the gas is passedr during the process of manufacture, through an acid bath, and sulphate is recovered continuously. This is a process which, as its original defects are overcome, is likely to be much. more generally adopted, although. some works which. installed the process. a few years ago have now abandoned it owing to working difficulties. Works Mains It is difficult to give definite rules, but the following will form a rough guide, based on particulars of many works :— Mains 5 inches diameter suitable for works of 3 to 4 million cubic feet per annum. „ 6 „ „ „ „ „ 6 „ 10 „ „ „ „ „ „ 8 „ „ „ „ „ 15 „ 25 „ „ „ „ „ 10 „ „ „ „ „ 30 „ 45 „ „ „ „ „ 12 „ „ „ „ „ 55 „ 90 „ „ „ „ „ 15 „ „ „ „ „ 100 „ 150 „ „ „ „ „ 18 „ „ „ „ „ 200 „ 300 „ „ „ „ „ 20-21 „ „ „ „ „ 350 „ 450 „ „ „ „ „ 24 „ „ „ „ „ 500 „ 600 „ „ „ „ „ 30 „ „ „ „ „ 600 „ 900 „ „ „ „ GENERAL NOTES ON THE LAYING OUT OF WORKS Having decided upon the sizes of buildings and plant, the engineer’s next task is that of setting these out on the site at his disposal. Each. site will have its own particular conditions, but the following points may be taken as applicable to all circumstances. The retort house and coal stores shouldbe adjacent to the point of coal intake and, in laying out, the disposal of coke must also be kept in mind. If possible,. arrange for the coal storage which is not under cover to be convenient for the retort house, and allow plenty of room for coke storage, and for pulling up carts, etc. High coke tips should be avoided, as they are expensive and give rise to excessive quantities of breeze. The coal and coke handling should be quite separate (on opposite sides of the building, if possible); and, if the site is not being filled up-at once, room should be left for enlarging without undue destruction. Provision should be made for any items of extension which may be contemplated. The site-