THE USE OF MASUT IN IRON AND STEEL WORKS.

New Zealand Times, Volume XXVII, Issue 5737, 4 November 1905, Page 9

THE USE OF MASUT IN IRON AND STEEL WORKS.

The heavy residue known as “astalki,” or “masiii,” from tho oil refineries of Baku, lias of lato years been largely used for steam-raising and fof heating and melting furnaces in the iron works of Russia. This may explain tho continual riso in the price, for m tho year 1900 nearly 4,} million tons of it were -reduced, which was about twice that of 1593, yet tho price had increased eightfold. Of the crude oil treated, 47 nor cent, appears as “masnt,” and always contains a notable proportion of water, which must be separated in storage-tanks having conical-bottomed outlets. Tho final separation of tins water is effected by steam coils in the reservoir, which raiso the temperate ro of the masnt to GOdeg or 80dcg Cent., end -at tho same time it si fficient fluidity for the burners. The average composition is—carbon, 87.5 per c<nt., hydrogen, 11 per cent.; oxygen, 1.5 per ‘ cent. Its specific gravity is about 0.91; temperature of ignition, about llOdeg Cent.; coefficient of expansion. 0,00091; and calorific value, about 10,700 calories. Mr F. Hick, in “Stahl und Eisen,” describes the methods adopted for obtaining an intimate mixture of tho liquid fuel and air as ? preliminary to combustion, which may bo classified as follows: —1. Gasification with subsequent mixing of the vapour with an air either compressed or at the 1 rc.ssuro of the atmosphere. 2. Atomisation of the masnt by means of tho so-fcalled “Forsunka” with (a) _ steam, ■b) compressed air, (c) by forcing the masut through. a- jet under pressure. An example of the first kind is the furrace of C. Spiegel, of St. Petersburg. Details of the construction and method of application in an implement works e eking steel forks and shovels are given, showing that, according to, size of tho work done, there may be 1 ton to 3i tons of material heated in a ninehours shift, with.a consumption of fuel varying from 10 to 33 per cent, by weight of tho steel heated, and a -waste of 1 to 2 per cent, of the steel thus treated. Tho temperature is about 635 deg Cent, in hardening furnaces, and ISOOdeg Cent, in heating blooms for rolling, and the working heat may le obtained in 20 to 30 from starting cold. A second modification of the same principle is shown as applied to a slab reheating furnace for a p!atc-mi!l As in the preceding example, there is a primary and a secondary air-supply. This furnace has a capacity of 30 tons of blooms, which are raised to a welding heat in three hours with a consumption of 10 per cent, of their weight in fuel, the waste heat being utilised to heat a steam boiler with 800 square feet of heating surface. In the second or atomising jet burner class the Nobel burner is tho host example of the use of steam. When compressed air is used tho burner is formed of two concentric tubes, tho central smaller one bringing the oil in from a high-level cistern, while tho air at 451 h per squai'o inch fills tho outer annular space. A fairly large combustion-chamber is necessary, and numerous secondary air-flucs in the sidewalls. For Section c of Class 2—viz., when tho fuel is injected into the furnace under pressure, an intermediate accumulator is necessary. This resembles a plain cylindrical boiler placed vertically, and divided by internal diaphragms into an upper and a lower reservoir, connected together by a series of small vertical tubes. The strained oil is pumped into the lower reservoir, and rises through the tubes (which are externally heated by high-pressure steani) into the upper, whence it issues to the burner under a pressure of 90Ih per square inch. This burner is the Korting atomiser or “Simplex Forsunka,” a plain tube closed at the point by a cap with a single hole, which may be 0,5 to 2 millimetres in diameter, tho orifice being controlled by a central pointed rod adjustable by a screw -and hand-wheel behind. The jet of oil is dispersed by impinging on the point of a triangular spreader placed in front of tho orifice, and becomes mixed with the heated air in the combustion-chamber. When applied to Siemens regenerative furnaces the burners are provided with an additional movement, so that they may bo drawn back at each reversal of tho valves. Furnaces with 15-ton to 25-ton charges have two jets at each end taking the place of tho ordinary gas ports, and a fifth in the centre of the roof. Only two regenerators are used, as the air alone' requires to be pre-heated.—“Engineering.” ,