586 THE COLLIERY GUARDIAN March 22, 1918. heated sides of the retorts. Higher temperature than origin produced tract ionisation ; lower temperature, contamination and supersaturation. Carbonising.—This was effected by carbonising the coal in thin vertical columns by means of the Tozer concentric retort, working under a high vacuum of over 20 in. of mercury. Experience had proved that perfect carbonisation could be effected under these conditions in about four hours or less. Products.—The products consisted of crude tar oils, ammonia, gas, and a remarkably easily ignitible smoke- less fuel or coke. The crude oils fractionated easily into motor spirits, middle oils (illuminating, fuel, Diesel), heavy oils (oils and lubricants), valuable tar acids (cresylic acids), pitch or bitumen. Oils.—The crude oils (water free) varying from 16 gals, to 80 gals, per ton of coal carbonised had, on an average, a specific gravity of 1*060 at 60 degs. Fahr. Under fractionisation these crude oils yielded com- mercial oils, which would only need cleaning by acid and alkali in the usual manner. In the event of the oils being used for Diesel engine purposes, the crude tar oils (water free) could be used in practically the crude state. It was, however, more profitable to separate the light oils (spirits) and to use the middle and heavy oils for Diesel engine purposes, fuel oils, etc. They had been proved to be quite suitable for that purpose. The crude oils fractionated on an average at the following ranges of temperature :— Per cent. Under 170 degs. Cent....... 3 8 170 degs. to 230 degs...... 22’4 230 degs. to 270 degs...... 14*0 270 degs. to 330 degs...... 20*6 Pitch ..................... 25*7 Special gravity 0*820 ,, » 0'930 „ ,, 0*060 „ „ 1’030 86*5 Loss about ..... 13*5 100*0 The purified oils freed from the valuable tar acids were of the “ paraffinoid ” series and contained 5 to 8 per cent, of paraffin wax. In point of specific gravity they were between a gasworks tar and a shale oil. The light oils (or spirits) had proved to be excellent motor spirits, resembling petrol in their efficacy. Naphthalene and anthracene were entirely absent from the oils. Tar Acids.—The tar acids contained scarcely a trace of carbolic, and were practically phenols and cresylic acids. The foregoing tar oils were produced at tem- peratures ranging from 900 degs. to 1,200 degs. Fahr. Ammonia.—The production of ammonia depended entirely on the nitrogen content of the coal operated upon, and it varied from 10 lb. to 28 lb. of sulphate. At the low temperature used it was not claimed that the yield of ammonia was as high as the yield obtained by gas works practice, but it was not far short. The sulphate produced would contain 25 per cent, of gaseous ammonia, but it was not necessary to manu- facture sulphate if concentrated ammonia was required, as the *k liquor” in which the ammonia was absorbed could be easily concentrated down to 0*880 ammonia solution if necessary. Gas.—The yield of gas averaged in bituminous coals 5,000 to 6,000 cu. ft. per ton, of about 700 to 800 B.Th.U. per cu. ft.; and in cannel coals the yield was from 6,000 to 8,600 cu. ft. per ton. That gas was washed or “ stripped” of its luminosity by treatment with the crude oil (one of the fractions produced from the crude oils obtained from the car- bonisation process would do well). That oil on distilla- tion yielded motor spirit, which, added to the spirit obtained by fractionating the crude tar oils, made a total yield from bituminous coal of some 2 to 3 gallons of spirit per ton and from cannel as high as 7 to 9 gallons. Practically the “ stripping ” process would yield approximately half the total yield of spirit obtainable per ton of coal. The stripping oil might be used over and over again after the spirit had been extracted. The non-luminous surplus gas was used to heat the works. Smokeless Fuel or Coke.—The residual coke, averaging 50 per cent, in the case of cannels to 75 per cent, in the case of bituminous coals, was a remarkable fuel, retaining as it did 7 to 10 per cent, of a volatile flammable non-smoky gas. Consequently it burned with a lambent flame—smokeless and yielding great heat. Its approxi- mate calorific value was 13,500 B.Th.U. per cu. ft. It was as easily ignitible as coal. Being produced under very great pressure, it was not unduly friable, and was an ideal fuel, for which from 28s. to 35s. per ton was easily obtainable. Whether made from bituminous coals or non-caking cannels its peculiar ignitible properties remained. From a great number of trials (on a commercial scale) of cannel coals and lignite of all ranges of quality extending over a number of years, the following were the average results obtained per ton of coal carbonised:— Bituminous Coal. Motor spirit ............... 2 to 3 gals. Middle oils ................ 4 to 5 gals. Heavy oils ................. 6 to 7 gals. Pitch....................... 25 to 30 gals. Sulphate of ammonia......... 231b. Fuel ....................... 15 cwt. Cannels. Motor spirit ............... 5 to 9 gals. Middle oils................. 13 to 14 gals. Heavy oils ................. 28 to 30 gals. Pitch....................... 2*05 cwt. Sulphate of ammonia......... 21’8 lb. Fuel ....................... 10 cwt. Lignite. Motor spirit ............... 2 gals. Middle oils................. 4 to 5 gals. Heavy oils ................. 7 to 8 gals. Pitch....................... 0*8 cwt. Sulphate of ammonia......... 18*5 lb. Fuel ....................... 15 cwt. In estimating the cost of the process and the profits, two factors were of prime importance—namely, the cost of the raw coal or cannel and the price obtainable for the products. A third factor was the question whether the process was to turn on the production of fuel or on oils, as that would determine the quality of the coal selected. Experience had shown that very inferior coals yielded good fuel results, but for a high yield of oils cannels and shales were certainly to be preferred. The cost of manufacture had not been fairly definitely settled. In the past the question of finding a customer for the gas produced bad been one of the main obstacles, but in electrical engineering and central station indus- tries a market had been acquired, and the Fuel Conser- vation Committee bad decided to follow this path. One of the great troubles in carbonising coal was the speed at which the heat could be passed through the coal. It had been established that 2J in. thickness of coal was the quickest basis for carbonisation. If that were exceeded the same speed of distillation was not secured ; 2 k in. gave a reasonable and fairly strong coke, and the distillation was very much more rapid than in any other process. One of the objections raised by high-temperature dis- tilling men to low-temperature vacuum operations was the fact that the low-temperature distillate was entirely differ- ent from the high-temperature results and the paraffinoid series alone appeared in the low-temperature distillate. They seemed to forget the fact that the same material which gave low-temper<«ture distillates would also give the benzenoid oil series, and he claimed that if by low- temperature distillate n i hey could have a larger bulk value from volatile or oil-producing material, it was not impossible for a low-temperature distiller to put the same material through a high-temperature fractioniser and eventually obtain a similar distillate. By means of the accompanying diagram, Mr. Paton pre- sented his conception of a central coal collecting, treating, distilling and power-producing plant. The idea of the system is to centralise the available low grade material at a certain point, described as a bulk station, where it passes through certain treatment and washing, the various grades being returned in divisions, as shown in sections 2. 3, 4, 5, 6 and 7 respectively. He claims to have proved, as a result of extensive tests, that this crude material would give a return of 10 per cent, of first grade slack, equal in all respects to some of the slack now sold for boiler firing purposes; 15 per cent, of a second grade slack, suitable for boiler firing and general combustion ; 15 to 25 per cent, would be avail- able for the production of metallurgical coke; whilst 40 per cent., representing the bulk of the material, would be used for low-temperature distillation—the primary object of which would be oil extraction; and 10 per cent., being low in volatile matters, would be passed directly to gas producers. Section 7 includes a, varying quantity of material obtained at different mines which would be available for the production of special minerals as indicated on the chart. From sections 4 and 5 metallurgical coke, oils, sulphate and gas would be obtained, section 4 being arranged on practically the same lines as the modern high-tempera- ture coking installations. Section 5 is a low-temperature distillation system, as outlined in the address. Section 6 is a gas producer section, into which the coke from section 5 will be passed in a red hot state. Section 9 represents a briquetting or patent fuel scheme, into which coke breeze and special coals suitable for briquetting will be converted into patent smokeless fuel for domestic use. Section 10 is essentially a large central power station of the type now embodied in the scheme of the Fuel Conservation Research Committee. In that station the whole of the gas will be converted into electrical power or transmitted direct in a gaseous state into the positions where the gas transmission is economically advantageous. Section 7 is of particular advantage in industrial communities where the load is variable, because it will be possible, by means of local absorption of power for reduction and fixation purposes, to normalise the day’s load. After the various operations outlined in the diagram, the entire waste ashes and refuse would pass back through section 8 to a collecting station, and be subse- quently used for gob stowing. Industrial Reconstruction Council.—The Industrial Reconstruction Council will hold the second of its series of important provincial meetings, at the Assembly Hall, Edinburgh, on April 3, at 8 p.m. Dr. Addison, Minister of Reconstruction, will be the principal speaker. The object of the movement is to arouse interest in the recom- mendations of the Whitley Committee for the establish- ment of a Joint Council in every industry. Coal Rebates at North-Eastern Railway Depots.—The Coal Controller has issued the following instructions with regard to dealers’ rebates at depots on the North-Eastern Railway:—(1) In no case shall any person on the sale of any coal, delivery of which is taken from a depot or siding on the system of the North-Eastern Railway, at which there are cells or other definite delivery accom- modation provided for particular colliery companies or traders, give or accept any rebate from the price charged to the public, except in accordance with the following requirements :—(a) No rebate shall be given to, or accepted by, any person other than a bond fide retail coal merchant or the consumer of the coal; (6) the amount of the rebate which may be paid to a bona fide retail merchant or consumer shall not exceed the amount of the rebate in operation between the same parties, in respect of the same description of coal, at the same depot, on October 3. 1917, and shall in no case exceed 2s. per ton. (2) Where the rebate to a retail merchant in respect of any description of coal, delivery of which is taken at a depot or siding, as aforesaid, is reduced so as to conform to the requirement of Article 1 of these instructions, the published price of the same description of coal, at the same depot or siding, shall at the same time be reduced by the same amount. (3) If any person acts in contra- vention of these instructions, that person is guilty of a summary offence against the Defence of the Realm Regulations. (4) These instructions shall take effect as from March 18, 1918. NEW COAL CONTROL DIRECTIONS. The Controller of Coal Mines has issued directions, under Regulation D.R.R. 9G-., prescribing that:— A. —No owner of a coal mine shall, without previous written notice to the Controller of Coal Mines: (a) incur any expenditure on the sinking, widening, or deepening of shafts (including underground shafts) or the continuance thereof; the making or driving of slants or adits for the purpose of hauling coal and of cross measure or stone drifts; the opening or reopening of seams; the erection or acquisition of any additional buildings, plant or machinery not strictly required for purposes of repair or maintenance; or (b) sell or otherwise transfer the ownership of any mine or part of a mine. The grant of authorisations by other Government Departments, such as, for instance, priority certificates or building licences by the Ministry of Munitions, or licences to import, must not be regarded as in any way committing the Controller of Coal Mines to approval of the expenditure thereby involved. The sending of any such notice, followed by the Controller’s acquiescence, does not in any way prejudge the question of the method in which such expenditure is to be dealt with in the accounts. B. —No owner of a coal mine shall, without the previous written authority of the Controller of Coal Mines, increase or decrease the wages or bonus of mine officials or workpeople otherwise than in accordance with the awards and agreements of Conciliation Boards or other duly constituted machinery (if any) for regu- lating rates of wages and bonus in the coal mining industry, such awards and agreements, if made during the period of control, not to be effective without the written authority of the Controller of Coal Mines; increase any director’s fees or other remuneration; increase the salary or other remuneration of any member of the managing, clerical or administrative staff whose present remuneration exceeds £'250 per annum; increase beyond the limit of £250 per annum the remuneration of any member of the staff whose present remuneration does not exceed £250 per annum; or grant any war bonus or other special advance to any member of the staff whatever his or her present remu- neration may be. {Note.—No authority is required for ordinary increases in salary or wages granted from time to time to members of such staffs provided that the resultant remuneration does not exceed £250 per annum. A list of all increases which have since the commence- ment of control been voted to directors or granted to those members of the managing, clerical, or adminis- trative staff whose present remuneration exceeds £250 per annum, is to be furnished to the Controller) ; close any mine or district of a mine or terminate the contracts of any workpeople or mine officials as the result of such closing or with a view thereto. {Note.—The owner of a coal mine must also give to the Controller 60 days’ notice of the termination of any lease under which he is working coal, if the termination will involve the closing or abandoning, or is due to the exhaustion, of the mine or any part of it.) In order that the Controller may be satisfied that the terms are reasonable he must be consulted and his approval obtained for the execution or renewal of any wagon repair contract; the execution or renewal of any contract for hire purchase or simple hire of wagons; any sale or other contract involving the transfer of ownership of wagons. The Controller must be immediately advised of the existence of any organised dispute. The foregoing directions apply to all parts of the undertaking in possession of the Board of Trade. Notices, or applications for authority, should be addressed to the Controller of Coal Mines. Holbom Viaduct Hotel. London, E.C. 1. SAFETY LAMP ORDER. In the London Gazette the Home Secretary gives notice that on March 9, 1918. he made the following Order in pursuance of section 33 of the Coal Mines Act, 1911 (а) To approve the following safety lamps for use in all mines to which the Act applies, subject to the con- ditions specified in the Schedule to the Order:— (i.) The Patterson Flame Safety Lamps, Types A5 and El, and Type E2 (for officials). (ii.) The “ Davis-Briggs” Oxymeter Officials’Lamp. (iii.) The Joel-Fors Electric Safety Lamp, Type 303M. (б) To amend and consolidate the specifications of the “ Ceag ” Miners’ Electric Safety Lamp approved by the Safety Lamps Order of August 26, 1913, and amended by later Orders under section 33 of the Act; and (c) To make amendments in the specifications of certain other safety lamps approved by previous Orders made under section 33 of the Act. Manufacture of Steel Castings.-—In the course of a paper on “ Some Notes on the Development of the Manufacture of Steel Castings,” read by Mr. Ernest F. Lange, at a meeting of the Manchester Association of Engineers, the author said he considered that it was clear that the consumption of steel after the war must be approximately one-third greater than it was before the war in order to engage the present plants, and it was equally clear that the United States was much more interested in this fact than was any other country, for it was the United States that would have to find the greater increase in outlet. The necessity for conserving our coal supplies will doubtless lead to great schemes in the future for the production of power in the most economical manner in very large units, situated near the pit mouth, from which centres the electric current could be distributed all over the land. Perhaps in those days even tonnage steel would be electrically melted. Mean while, the duplex system, combining the manufacturing advantages of the Bessemer and open hearth practice, was extending, to which had now been added the triplex system of electrically refining metal thus produced for the production of special qualities of steel.