The bones from slaughter-houses or knackers' yards are employed for manufacturing either gelatine and phosphate of lime, or else bone charcoal and ammoniacal salts. Fresh bones, to which fragments of muscle still adhere, are soaked for twenty-four hours in hot water to allow them to be readily cleaned. When the soaking is finished, the liquid is run off, and the bones, freed from fleshy particles, are crushed between channelled rollers; they are then boiled to extract the fat. The boiling is carried out in the following manner: — The crushed bone is received in a wrought-iron basket, which can be transferred by a crane to a wooden vat containing water. This water can be rapidly boiled up by a steam coil lying on the floor of the vat. The boiling water extracts the fat from the bone, and causes it to rise to the surface. The fat is collected by a skimmer, strained through a sieve, and employed for soap-making. After two and a half hours' boiling with water the bones give up no more fat; the basket is then lifted out, and the contents submitted to copious washings. The bone is then thrown out in heaps, and allowed to dry spontaneously. When dry it is passed through mills, which reduce it to fragments of suitable size for making bone charcoal. These are freed by sifting from the fine powder which is employed for making phosphatic manure. The coarser fragments are then submitted to calcination, either in crucibles of clay or cast-iron, or in continuous furnaces. Calcination in crucibles does not allow the volatile products to be collected, as these burn in the heating chamber; 72 AMMONIA FROM BONES 73 by using retorts the volatile products can be collected and the gases utilised for the partial heating of the retorts. A group of retorts, which are either of cast-iron, or better of fire-clay, and of cylindrical or oval section, are arranged vertically in a chamber which can be heated by one or two fires. Each retort is furnished at the top -with a charging box, of cast-iron, situated outside the brickwork; this box has a wide opening in the bottom, which is closed by a luted plug, and one at the side for conveying the vapours and gases to the condensers. Each retort has also an opening at the bottom, which is closed during the distillation. The volatile products pass into a hydraulic main containing water, where a preliminary condensation takes place. A small stream of water is allowed to flow into the main to keep the level of the liquid constant, so that the delivery pipes may always dip to the same depth, and also to prevent the deposition of solid ammonium carbonate. The vapours which escape from the hydraulic main are carried first through a condenser heated by an exterior current of water, and then through a scrubber, where they meet a small stream of cold water, which frees them as perfectly as possible from the ammonia they contain. They are then passed into the retort fires and burnt. The liquors from the condenser, the hydraulic main, and the scrubbers, are collected in a wrought-iron vat, and serve for the manufacture of ammoniacal salts. The liquid from the condenser is of 14° to 15° Be., that from the scrubber 1° or 2° only. On remaining at rest these liquids separate into two layers. An upper oily one, of very complex composition, is known as Dippel's oil; it contains a large number of compounds, especially bases of the pyridine series, of which at present no use has been made. These oils are either burnt in the furnaces or used for making illuminating gas. The lower aqueous layer is a solution of ammonium carbonate contaminated with tarry substances, and is employed for the manufacture of ammoniacal salts by distilling it and absorbing the ammonia by an acid. The salts obtained are deeply coloured by the small quantities of oily products which they contain. One hundred kilos. (2 cwt.) of bone, treated as described, yield 6 to 7 kilos, of ammonium sulphate, containing 18 to 19 per cent, of nitrogen and 17 to 2 kilos, of oil. A method formerly employed in France, and still occasionally used, for converting the carbonate of ammonia of the crude liquors into sulphate, consisted in filtering the liquor, after freeing from tar. 74 AMMONIA AND ITS COMPOUNDS through a layer of gypsum, when decomposition took place with formation of carbonate of lime and sulphate of ammonia, which merely required concentration. For the manufacture of ammonium chloride h-om these liquors, see Chap. V. § 2. Ammonia from Nitrogenous Waste. Waste wool, hide, leather, horn, feathers, sponge, etc., containing 6 to 15 per cent, of nitrogen, is habitually worked up into manure. The decomposition of these substances in the soil is extremely slow, it is therefore advantageous to convert their nitrogen into ammonia. UHote's method consists in treating them with a 10 per cent, solution of caustic soda, which either dissolves them completely or brings about a complete disintegration. The mixture obtained is made into a paste with lime and introduced into a cast-iron retort. The retort is carefully heated to avoid decomposing the ammonia, and the vapours are passed into chamber sulphuric acid, in which they are condensed. Towards the end of the operation the retort should be raised to a red heat. The white pulverulent residue consists of carbonate of soda and lime, and when treated with water reproduces caustic soda, which is used over again. In this way the whole of the organic nitrogen in the original substance may be recovered as sulphate of ammonia. The sulphate obtained directly by this process is coloured, which however is no obstacle to its use in agriculture. Its purification, if necessary, would be easy. § 3. Ammonia from Beetroot (Vinasse). The manufacture of ammoniacal salts at the same time as salts of the methylamines, by calcining the residue from the distillation of beetroot spirit, has been carried on for some years. A mixture is obtained of gaseous and condensable products, which on cooling yields a complex tarry liquid containing carbonate, cyanide, chloride, sulphide, etc., of ammonia and methylamines. When this mixture is neutralised with an acid and evaporated, the ammoniacal salts, which are less soluble than those of the methylamines, can be crystallised out. The mother liquor contains chiefly salts of trimethylamine and diraethylamine, and is used for the manufacture AMMONIA FROM BEETROOT 75 of methyl chloride.^ Hydrochloride of trimethylamine is decom- posed by heat. At about 285° C. the gaseous products evolved consist eotii'ely of free trimethylamine and methyl chloride ; whilst the solid residue contains hydrochloride of monomethylamine and unaltered hydrochloride of trimethylamine. The decomposition is represented by the equation 3 N(CH3)3. HC1 = 2N(CH3)3-h 2CH3CI + N(CH8)H2. HCl. Above 305° the residue consists entirely of monomethylamine hydrochloride mixed with ammonium chloride. The gaseous products then contain much ammonia mixed with methyl chloride. Finally, at about 325°, the substance is wholly decomposed or sublimed. Above 305° the principal reaction may be represented by the equation N(CH3)H2. HCl = CH3CI + NH3. The products of a dry distillation of trimethylamine hydrochloride are therefore methyl chloride, trimethylamine, and ammonia. The hydrochloride of dimethylamine behaves in a similar manner. The gaseous mixture, passed into commercial hydrochloric acid, deposits the alkaline products, ammonia and the methylamines, whilst the methyl chloride, washed with water, and collected in a gasholder, is liquefied by compression after being completely dried by sulphuric acid. Methyl chloride is now manufactured commercially by this method, and is used both in the preparation of coal tar colours and in freezing machines. The chlorhydrates of ammonia and the methylamines are easily separated by crystallisation and centrifugal extraction, ammonium chloride being much less soluble than the other salts. The methylamine salts in the mother liquors are reworked for making methyl chloride. The sal ammoniac obtained by this process is rendered impure by chlorides of iron and lead from the boilers and evaporation coils ; to purify it for use in Leclanch^ batteries, it is redissolved and treated with ammonium sulphide to precipitate the heavy metals. By recrystallisation and hydro-extraction a very pure product is obtained, which finds its application in telegraphy. § 4. Ammonia from Peat. 1. Peat is a highly important fuel, which at the present time is being formed by the decomposition of aquatic plants in marshy localities. Peat often contains the remains of trees which have undergone slow decomposition under water, and which have nourished the growth of plants which only live on decomposing lignite. These plants have grown and perished, and their remains have served as the soil of a new layer of vegetation. In this way a deposit of peat has been gradually formed, the thickness of which has continued to increase until it reached the surface of the water. Peat bogs have therefore had their origin either in a lake or pool, or even in an arm of the sea, which have in this way become gradually filled up. It is the opinion of some authorities that thirty to forty years are required to form a layer of peat 1 m. in thickness; others estimate that under the best conditions the production does not exceed 0'6 metre in a century. Both views are correct to this extent, that a century is required to form 0'6 m. of peat of good quality, whilst in thirty to forty years it is possible for a growth to form 1 m. thick of an imperfect peat which is not worth the trouble of working. It is of import- ance that the water of a peat bog should be renewed, for in stagnant water the decomposition of the vegetation would be complete, and peat would not be formed; but the water-current must be a slow one, and must not remove the debris on which the formation of peat partly depends. There are found in Picardy two kinds of peat : one compact and foliated, which has been produced by the decomposition of wood or large plants ; the other light, derived from the Equisetacem rushes, and mosses which have grown on the former. This spongy peat is sometimes rich in mineral matters, which have been intro- duced by floods. These mineral matters, crushed shells and stones, make the peat difficult to burn. Such peat {tourbe d cendres) is of very inferior value. Peat when dug out from the bog can be worked up into a soft paste like clay, and moulded into bricks (briquettes) hese, exposed to the air under sheds, rapidly lose most of their water and shrink considerably, sometimes to one-sixth of their original bulk. When, however, peat ceases to lose weight under these conditions, it is far from being dry ; it retains a proportion of hygro- metric moisture which is the more considerable the poorer the peat is in mineral matters. Thus the peat of first quality from the Somme retains 10 to 30 per cent, of water after long exposure AMMONIA FROM FEAT 77 to air, whilst under the same conditions an ashy peat will retain only 5 to 15 per cent. The proportion of moisture retained by peat depends also on its physical condition. Thus, when it has been well kneaded, then moulded, and dried for six months under a shed, peat of the first quality is compact, and contains only 10 to 14 per cent, of moisture, whilst bulky peat^ under the same conditions of exposure may contain 25 to 30 per cent. A satisfactory product should be hard and compact, have a density varying from 045 to 0*7, contain not more than 10 to 15 per cent, of moisture, and 5 to 15 per cent, of g,sh. The peat as soon as it is dug out is treated as follows, according to Challeton's process : — It is first thoroughly disintegrated by a pulping machine, and then thrown upon an oscillating sieve, which allows the pulp to pass through, but keeps back the roots and coarse herbaceous fragments, which are utilised as fuel in the boiler fires of the establishment. The pulp falls into a wooden tub, where it is kept in suspension by a mechanical stirrer, whilst the sand, chalk, and fragments of shells are allowed to settle. This apparatus might be replaced by a machine such as is used for washing small coal. The pulp is now pumped out of the tub into wooden frames 2'5 m. square and 0'6 m. deep, where the water drains away from it; or any other suitable form of filter may be used. When sufficiently drained to be plastic, the peat is moulded by hand and the bricks are dried under a shed. Good peat, like that of Essonnes or the Somme, which contains neither sand, shells, nor more than about 2 per cent, of extraneous mineral matters, can be dried without washing. A much simpler and wholly mechanical method of treating peat has been established by Messrs. Bocquet and Bernard at Mareuil. Their process converts the original peat into a homogeneous paste, and yields hard, firm bricks of one quality only. Two different modes of procedure are adopted, according to circumstances : (1) If the peat bog is of sufficient size, the whole apparatus is put upon it on a floating dredge. The peat brought up by the dredge falls into a mill, where it is converted into a homogeneous pulp. This pulp is delivered into moulding trucks, where it is shaped into bricks, lightly pressed, and deposited on a drying floor. (2) If the bog is not capable of floating a boat, the peat is dug out by an excavator. In this case two parallel tram lines are laid down ; one carries the excavator, the other the trucks for removing the peat to the factory. The pulp delivered by the mills is run into a tilt waggon, which carries it to the moulds, and the bricks are treated and dried as before. Challeton's process gives the purest product, but is expensive ; by Bocquet and Bernard's process, on the contrary, the entire peat is pulped and made into bricks containing from 5 to 12 per cent, of mineral matter, and retaining 12 to 15 per cent, of water. When treated by Challeton's process, the Mareuil peat loses 50 per cent, in weight by the removal of the coarse portions, and retains only 3 per cent, of mineral matter, but its price is more than double. Machine pulping, by allowing greater compression than is obtainable by hand, reduces to one-half the number of bricks obtained from a given quantity of peat. Great economy is thus attained, and the bricks keep their shape, and their drying being slower they acquire greater density. Kolb, by a series of reduction tests with litharge, has deter- mined the calorific power of peat from various sources : he finds for good dry peat a calorific power of 3100 to 3500 calories The calorific power of oak-wood being 3500 calories, and that of the best coal about 6000 calories, it is obvious that peat is a very im- portant industrial fuel. It may be utilised in four different ways — (1) By burning it directly, after removal of its moisture by stoving ; (2) by converting it by carbonisation into charcoal, which can be used in blast furnaces ; (3) by converting it into producer gas, together with inferior fuel, which cannot be used in this way alone ; (4) by using it alone in special gas producers. By carbonisation in closed vessels, peat yields a hard charcoal, 60 per cent, of combustible gas, a tar particularly rich in phenols, paraffins, and acetic acid, and an ammoniacal liquor containing as much as 2 parts of ammonia per 100 of peat. These ammoniacal products can be collected even when the peat is converted into producer gas. As stated above, coal, when distilled, produces on the average 6 kilos. (13 lbs.) of ammonium sulphate per ton ; eau vanne, 9 to 10 kilos. (20 to 22 lbs.) per cubic metre; whilst the best peat may yield 80 kilos. (176 lbs.) per ton; that of second quality, 68 kilos. (150 lbs.); and of third quality, about 40 kilos. (88 lbs.) per ton. Peat is therefore the richest raw material, and the most advantageous to work for ammonia, as will be seen below. AMMONIA FROM PEAT 79 When peat is to be burnt under steam boilers or in metal- lurgical furnaces, it must first be deprived of its moisture, and when it is to be converted into charcoal this is equally desirable, so as to obtain the greatest yield. For drying, the peat must be exposed for thirty-six to forty-eight hours to a temperature which must not exceed 100° C, for even at 110° or 115°, according to Kolb, decom- position commences. Lencauchez has invented a brickwork stove which will hold 40 to 50 tons of peat, and which can be heated by waste heat from various sources. The description of this ingenious apparatus would take us too far from our subject; we therefore refer the reader to Lencauchez's treatise on Peat (Lacroix), from which we have drawn much information on this subject. The well-dried peat can be burnt under boilers, in locomotives, or in blast furnaces ; after carbonisation it is employed for domestic purposes, or instead of wood charcoal for metallurgy. The manufacture of charcoal from peat can be carried out in a modified Knab furnace, worked on the regenerator system. The vapours and gases given off are cooled in condensers resembling those of
Key Takeaways
- Bones can be processed to extract valuable ammonia compounds for use as fertilizers or chemicals.
- The process involves soaking, boiling, and distillation of bones to collect fat and ammonia-rich liquids.
- Ammonium sulphate is a key product that can be obtained from this process.
Practical Tips
- Utilize animal byproducts like bones for resource recovery in survival situations.
- Understand the basic principles of bone processing to adapt techniques to modern materials.
- Store processed bone products properly to prevent spoilage and maintain their value.
Warnings & Risks
- Handling raw bones can attract vermin or cause injury if not handled carefully.
- The process requires careful temperature control to avoid decomposition and loss of ammonia.
- Ammonia compounds are corrosive; proper storage and handling are essential to prevent damage.
Modern Application
While the specific techniques for extracting ammonia from bones may be outdated, the principles of resource recovery and waste utilization remain relevant in modern survival preparedness. Understanding how to process organic materials can help in creating sustainable resources during emergencies. Additionally, the knowledge of using peat as a fuel source is still valuable, especially considering its high calorific value compared to other biomass fuels.
Frequently Asked Questions
Q: How much ammonia can be extracted from bones?
One hundred kilos (2 cwt.) of bone yield 6 to 7 kilos of ammonium sulphate, which contains 18 to 19 per cent nitrogen and 1.7 to 2 kilos of oil.
Q: What are the steps involved in processing bones for ammonia?
Bones are first soaked in hot water, then crushed and boiled to extract fat. The remaining bone is calcined to release volatile products, which are collected and used for heating or further distillation to produce ammoniacal salts.
Q: Can this process be adapted for modern survival situations?
Yes, the principles of resource recovery can be applied in a simplified manner. For example, using bones from livestock for fertilizer or processing peat as an energy source are still relevant techniques that can be adapted to modern settings.
Q: What is Dippel's oil and how is it used?
Dippel's oil is an upper oily layer obtained during the distillation process, which contains a complex mixture of compounds. It can be burnt in furnaces or used for making illuminating gas.
Q: How does peat compare to other fuels like coal and wood?
Peat has a higher calorific power than wood (3100-3500 calories) but is lower than the best coal (6000 calories). It can be used directly for burning, converted into charcoal or producer gas, making it a versatile fuel source.