Treatment of
Non-Ferrous Metal Process Waste at
Kynoch Works, Birmingham, England
E. H. F. STONE, Chemical Services Engineer
Engineering Services Division
Imperial Metal Industries (Kynoch) Limited
Birmingham, England
INTRODUCTION
SCOPE OF PROBLEM
A redrainage and effluent treatment system costing approximately a third of
a million lbs has recently been completed at the Kynoch Works of Imperial Metal
Industries, Ltd.   In order that the need for capitol expenditure of this magnitude
may be appreciated,  it is necessary first to give a brief outline of the relevant
factors.
Kynoch Works is concerned with the fabrication of non-ferrous metals and
alloys. In the course of this work metals are immersed in dilute sulphuric acid for
removal of oxide left after annealing. The metals involved are copper and brass,
with smaller quantities of cupro-nickel alloys, and latterly titanium and the newer
metals, for which stronger liquors are needed. Apart from these newer metals the
characteristics ofthe effluent remained unaltered for many years. Before redrainage of the factory began there were 13 discharges to the Tame River from the
factory site, which has an area of nearly 300 acres, the total quantity of effluent
being between 1.5 and 2. 0 MGD.
The works is situated on the north side of Birmingham and the most obvious
means of disposal of liquid effluents is to the Tame River system, of which the
Tame River forms a part. It is in fact to this river, lower down its course, that
the whole of Birmingham sewage is ultimately discharged.
THE RIVERS (PREVENTION OF POLLUTION) ACT.  1951
By the Rivers (Prevention of Pollution) Act, 1951 it seemed that the River
Board would have legal powers to make by-laws and enforce standards of which
the following four are typical and of particular interest to the metals industries.
The discharge should not: 1) contain solids in suspension in excess of 30 mg/1
by weight; 2) have a pH value less than five or more than nine in the recognized
scale; 3)(a)include arsenic, cadmium, chromium, copper, lead, nickel, or zinc,
either individually or in total, in excess of one mg/1 by weight; (b) include free
chlorine in excess of one mg/1 by weight; (c) include cyanide (CN) in excess of
one mg/1 by weight; and 4) have a temperature in excess of 25 C.
Initially, it had been intended to divert the effluent to the City sewers and to
treat so as to comply with the following specifications:
1.  The sum total of all metals other than: (i) copper,  chromium,   zinc.
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