Action of this nature not only
means that the acetylene is diminished in quantity and quality by partial
decomposition, but it also means that the make is smaller owing to
imperfect decomposition of the carbide: while over and above this is the
liability to nuisance or danger when a mass of solid residue containing
some unaltered calcium carbide is removed from the apparatus and thrown
away. In fact, whenever the residue of a generator is not so saturated
with excess of water as to be of a creamy consistency, it should be put
into an uncovered vessel in the open air, and treated with some ten times
its volume of water before being run into any drain or closed pipe where
an accumulation of acetylene may occur. Even at temperatures far below
those needed to determine a production of tar or an oily coating on the
carbide, if water attacks an excess of calcium carbide somewhat rapidly,
there is a marked tendency for the carbide to be "baked" by the heat
produced; the slaked lime adhering to the lumps as a hard skin which
greatly retards the penetration of more water to the interior.
COLOUR OF SPENT CARBIDE.--In the early days of the industry, it was
frequently taken for granted that any degradation in the colour of the
spent lime left in an acetylene generator was proof that overheating had
taken place during the decomposition of the carbide.
Pages:
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122