280 THE COLLIERY GUARDIAN. February 9, 1917. ________________________________________________________________________________________________________________________________________ out by a ram, hydraulic power being used for both pur- poses. The coke is quenched on the landing platform, the necessary water being sprayed from a hose., and supplied from two dams with a total capacity of 1| million gals. It is estimated that the loss from breeze, ash, etc., is about 2 per cent., but this varies consider- ably, and is dependent upon the quality of the coal, atmospheric conditions during burning, and thorough quenching at the time the charge is just ripe. The generated gases are allowed to go to waste, and the general lay-out of the works appears somewhat unfavour- able for economic handling. An average sample of coke gave the following analysis : Hygroscopic moisture, 0'46 per cent.; volatile matter, 1'40; fixed carbon, 80-08; ash, 17-64; sulphur, 0’42 per cent. Specific gravity, 1-880. Ash, light buff-coloured, semi-flocculent. Coke, dark grey in colour, dense, and hard; pieces of shaly material visible in the coke; should stand the weight of a heavy burden in a smelting fur- nace, and not readily broken on handling. The ash con- tains about: Moisture, 0-09 per cent.; silica, 49-70; alumina, 31'82; ferric oxide, 4-20: lime, 5-82; end sulphur trioxide, 1-79 per cent. North Bulli. The coke ovens of this company were erected in 1906 at Coledale, on the Illawarra Railway line, 38 miles from Sydney, and 17 miles from Port Kembla. The coal used is mainly obtained from the Bulli seam as worked at the North Bulli Colliery, distant between 200 and 300 yds. from the ovens. Analyses of coal from this colliery are as follow :— Per cent. Per cent. Hygroscopic moisture ... 0'83 ... 0'43 Volatile hydrocarbons ... 22'79 ... 24’22 Fixed carbon ........... 63'97 ... 62'98 Ash ..................... 12'41* ... 12'37+ 100'00 ... 100'00 Sulphur ................. 0'519 ... 0'398 Specific gravity ......... 1'403 ... 1'415 Coke..................... 76'38+ ... 75'35§ Calorific value (lb.) ..... 12'7 ... 12'4 * Light grey, semi-granular, f Light grey, granular. J Fairly swollen, firm and lustrous. § Slightly swollen, firm and lustrous. The coal is transported by a mechanical conveyor to the Carr disintegrator, a reserve storage pit also being used for receiving slack from other collieries when it is necessary to purchase extra supplies. From the disin- tegrator the ground coal, or duff, is mechanically con- veyed to a storage bin, from which it is removed to the ovens by electrically-operated motors travelling on parallel sets of rails, and moving two canisters of duff at a time to each charging port, of which there are two per oven. These latter are of the rectangular beehive type, provided with a single vertical flue leading to la chimney stack about 9 ft. high, one stack serving every two ovens. The ovens are built in two sets of 52 and 54 respectively, with a continuous overhead connection for charging. The dimensions of the former are 20 ft. long, 6 ft. 2 in. high to the crown of the arch, and 7 ft. wide at one end, tapering to 6 ft. 8 in. at the other, whilst the latter are 19 ft. long, the remaining dimen- sions being the same. The periods of burning are 48 and 74 hours, the charge for the former being 6 tons of duff, and the latter from 8 to 9 tons. After the coking process is completed, the doors of the ovens are raised by hydraulic power, and the charge pushed out by a steam- driven ram. The coke is partially quenched on the landing Stage with a sprayer designed by Mr. Miller (the manager), which is moved along an overhead wire rope to the neces- sary position, and consists of a horizontally suspended pipe length, with radiating apertures extending the width of the charge, and connected by a length of hose to the main service pipe. Further quenching is done by a hose on the coke bench, and it is estimated that the wastage in a change after withdrawal approximates 3 per cent. No use is made of the generated gases. The daily output is from 185 to 190 tons from 37 ovens, and the number of men employed 50. The coke produced during 1915 was about 50,000 tons, approximately 70,000 tons of slack coal being used, or about 71 per cent, of coke. A sample of the coke gave the following analysis :— Hygroscopic moisture, 0-59 per cent.; volatile matter, 1-18; fixed carbon, 80'59; 'ash, 17-23; sulphur, 0'41 per cent. Specific gravity. 1'847. Ash, buff-coloured, semi- flocculent. Coke, dark grey in colour, dense, and hard, with very rough surface. Should stand the weight of a heavy burden in a smelting furnace, and is not readily broken in handling. The ash contained : Moisture, 0-06 per cent.; silica, 50'00; alumina, 25'70; ferric oxide, 10-60; lime, 5'02; magnesia, 2-47; and sulphur trioxide, 1'91 per cent. South Clifton Coke Works. The coking plant of the South Clifton Coal and Coke Company was established in 1900, and is situated along- side the colliery shaft, adjacent to the Illawarra Railway- line at South Clifton, 36 miles from Sydney, and 16 miles from Port Kembla. Only slack coal is used, and is obtained from the Bulli seam at the South Clifton pit workings. Analyses of this coal are as follow, the ash being light grey, semi- granular, whilst the coke is slightly swollen., firm, and lustrous :■— Per cent. Hygroscopic moisture.......... 0'69 Volatile hydrocarbons ......... 22'02 Fixed carbon.................. 65'61 Ash........................... 11'68 100'00 Sulphur ........................ 0'466 Specific gravity.................. 1 '384 Coke ............................ 77'29 Calorific value (lb.).............. 12'8 The whole of the slack coal is passed through a Carr disintegrator below the colliery screens, the method of handling both the slack and duff being a mechanical overhead conveyor system, discharging from either side. The ovens are of the old-fashioned beehive type., built of brick and rubble stone work, 66 in number, and of the following dimensions : 12 ft. in diameter, and 7 ft. 6 in. high. They are arranged in benches of 24 and 42 ovens, situated on either side of the colliery, the ovens being placed back to back in each bench. The burning is divided into 72-hour and 96-hour periods, the duff charge for the former being 4 tons and for the latter 5 tons. Internal quenching is adopted, the water supply being obtained from surface catchment. After quenching, the coke is withdrawn by hand, about 10 per cent, of the product being bagged, and the remainder loaded into railway trucks for transport. It is estimated that the toss from breeze and ash approximates 2 per cent., or about 1| cwt. per oven, and is composed largely of ash. The generated gases are allowed to go to waste, and although mechanical charging is adopted, the type of ovens do not lend themselves to economic handling. The output of coke for 1915 was 16,300 tons, obtained from 21,725 tons of slack, and 30 men were employed at the works. An average sample of coke analysed as follows :— Hygroscopic moisture, 0-81 per cent.; volatile hydro- carbons, 110; fixed carbon, 82'49; ash, 15-30; sulphur, 0'30 per cent. Specific gravity, 1-832. Ash, buff- coloured, semi-flocculent. Coke, dark grey in colour, dense, hard, and compact; should stand readily hand- ling without breaking, and the weight of a heavy burden in a smelting furnace. The ash contained : Moisture, 0'06 per cent.; silica, 49-18; alumina, 27-80; ferric oxide, 9'55; lime, 5'40; magnesia, 2-55; and sulphur trioxide, 1'79 per cent. Coal Cliff Coke Works. The works of the Illawarra Coke Company Limited were erected in 1913 at Coal Cliff, adjacent to the Illa- warra Railway line and Coal Cliff Colliery, 34 miles distant from Sydney by rail, and 18 miles from Port Kembla. Only slack coal is used, the supply being obtained almost entirely from the Coal Cliff Colliery. An I Fig. 3.—By-product Coke Ovens, Broken Hill Newcastle (N S.W.). elaborate conveyor belt system, 300 ft. long, with auto- matic coal weighing attachment, and capable of hand- ling 100 tons of slack per hour, transfers the coal from the colliery hoppers to the coke company’s bins. It is there screened, the fines being fed into the “ duff ” hopper direct, whilst the coarser portion is first passed through a Carr disintegrator. With the exception of the oven door lifter, which is worked by hydraulic power, all the mechanical arrangements are operated by elec- tricity supplied by the colliery plant. The ovens, of which there are 50, are of the improved beehive type, with the following dimensions : Length, 32 ft.; width, 9 ft. 3 in., tapering to 9ft.; and height, 7 ft. 6 in. Each oven has four overhead charge ports, and one stack is provided for every two ovens, whilst the two canisters for conveying the duff from the store bin to the oven are fitted with a double discharge, and carry sufficient for a full oven charge. Analyses of average samples of coal from the Coal Cliff Colliery are as follow :—■ Per cent. Per cent. Hygroscopic moisture ... 0'57 .. 0'85 Volatile hydrocarbons ... 22'93 .. 22'00 Fixed carbon . 62'55 .. 65'37 Ash ... 13'95* .. 11'78* 100'00 .. 100'00 Sulphur ... 0'328 .. 0'341 Specific gravity ... 1'391 .. 1'394 Coke ... 76'50+ .. 77'151 Calorific value (lb.) ... 13'4 13'4 * Light grey, granular. + Slightly swollen, firm and lustrous. J Fairly swollen, firm and lustrous. A sample of the unwashed duff as fed into the ovens was analysed with the following result:—Hygroscopic moisture, 0-71 per cent.; volatile matter, 23-73; fixed carbon, 63'39; ash, 12-17. Coke, 75'56 per cent. Sulphur in coal, 0'398 per cent. Ash, light grey in colour, semi-flocculent. The hours of burning are arranged in 72-hour and 96-hour periods, the charge for the former being 16 tons, and for the latter about 20 tons 6 cwt. It is estimated that the recovery is about 69 per cent., and the output per oven 25 tons of coke per week. After coking is com- pleted, the doors of the oven are raised by the hydraulic lifter, and the coke pushed out' by a double-racked Buchanan ram, worked by electricity. The quenching is don© on the landing stage by a locally-designed cage sprayer,, suspended on an overhead rail, and provided with solid iron sides to prevent the charge spreading, whilst six overhead perforated pipes with two separate water feeds pour a considerable volume of water on to the coke as it passes through the cage. The ram pushes the charge right across the landing stage, and it slides into a travelling hopper for removal to mechanical con- veyors. As it slides into these, it is again sprayed, and then passed over screens to railway wagons, or to another elevator fo-r dumping on the reserve supply- heap. The specially-constructed wagons carry a full load of from 8-J to 9 tons of coke without hand packing. The loss in the form of breeze or burnt coke is com- paratively small. The generated gases are not used, for apparently it suits the company better to obtain the necessary power from the Coal Cliff Colliery plant, and to adopt a type of oven best suited to their coke require- ments. The present maximum weekly output is 1,250 tons, practically all of which is absorbed by the smelters at the Mount Morgan Mining Company. The company- employ about 20 men, every effort being made to adopt mechanical appliances which will reduce the number oi hands required to a minimum. The necessary water is obtained by gravity from a dam with a capacity of 12 million gals., and an excellent catchment, so that pro- vision has been made for even very droughty conditions. A representative sample of the coke gave the follow- ing results on analysis :—Hygroscopic moisture, 0'48 per cent.; volatile matter, 1-40; fixed carbon, 82-62; ash, 15'05; sulphur, 0-45. Specific gravity, 1'847. Ash, buff- coloured, semi-flocculent. A sample of “black ends ’’ obtained was found to contain 13'07 per cent, off ash, 0'32 per cent, of sulphur, and 1-29 per cent, of hygro- scopic moisture. The composition of the ash contained in the coke is; Moisture, nil; silica, 46-50 per cent.; ■alumina, 28'63; ferric oxide, 7-30; lime, 10'22; and sulphur trioxide, 3'37 per cent. Northern District Coke Works. The Broken Hill Proprietary Steel Works, Newcastle, erected a modern by-product coking plant (fig. 3) in con- junction with their steel works at Port Waratah, Newcastle, in 1915. The coal used is obtained from several collieries working on the Borehole seam; and crushed coal as charged to the ovens gave the following analyses :—Fixed car- >>on, 55'30—56'47 per cent.; vola- tile hydrocarbons, 31'43—32'84; ash, 11'9—12-1; sulphur, 0-50— 0'80 per cent. Both slack and large coal are used, the former being fed direct to a Carr disintegrator crushing 70 per cent, through 20 meshes to the inch, but the latter is first passed through toothed rolls. The crushed coal is then elevated to an overhead bin, and fed into a charg- ing machine, with four hoppers, registering with the oven-charging holes. The ovens are of the most modern type, built after the Semet-Solvay recuperative pat- tern, land 66 in number. The dimensions are 36 ft. long, 8 ft. Steel Works, high, and 1 ft. 6 in. wide. The charge per oven is 7'9 tons of crushed coal, the burning period 24 hours, wnd the loss from breeze (small coke) and burnt coke is 2| per cent. By-products are recovered, the generated gases being used for lighting and heating, a.nd the tar sold to a separate company for further treatment. A complete plant for the preparation of sulphate ol ammonia has been installed, and is producing a salt of excellent quality. An analysis of the gas is as follows :—Carbon dioxide, 2'8 per cent.; hydrocarbons, 4'0; oxygen, 0-5; carbon monoxide, 7'7; methane, 32-6; hydrogen, 49'0; nitrogen, 2'8; sulphuretted hydrogen, 0'3 per cent. British thermal units per cu. ft. of gas, 602. Eight gals, of tar per ton of coal. Average daily gas production, six million cu. ft. After coking is completed, the charge is pushed out by an electrically-operated ram, through a Darby quencher, and subsequently sprayed on the coke bench to complete the quenching, the water supply being obtained from the Hunter River District Service. The total output is absorbed by the siteel works, and the quality, as indicated by the following analysis, although somewhat high in ash, and inclined to be brittle under pressure, would appear to be admirably adapted for requirements :—Volatile matter, 0'33—0-57 per cent.; ash, 16'1—18-0; sulphur, 0-39—0'46 per cent. Apart from the Australian Coking and By-Products Company’s works at Islington, not now working, these are the first by-product ovens in the State, and it is probable that the success or otherwise of this process as applied to the New South Wales coals will be a great object lesson to coke producers throughout the State. The percentage of coke ranges from 61'78 in the earlier outputs to 73-9 in more recent production, and this com- pares very favourably with other coke producers in the State. One hundred and thirty-five men are employed at the coke works, and the output for six months ended December 1, 1915, was 43,968 tons of coke produced from 71,160 tons of coal, while from the latter date to May 3, 1916, 48,496 tons of coke have been produced from 72,698 tons of coal. A sample of the coke gave the following results on analysis:—Hygroscopic moisture, 1'38 per cent.; vola- tile matter, 0'79; fixed carbon, 81-04; ash, 16-42; sulphur, 0'37 per cent. Specific gravity, 1'809. Ash,