§ 58. Mr. Sydney Irving
asked the Minister of Housing and Local Government and Minister for Welsh Affairs if he will state the estimated average rate of efficiency in the arrestment of dust of precipitators installed in Thames-side Cement Works in each of the last 10 years, and the highest and lowest figure reached by any 101W individual precipitators to achieve this average.
§ Mr. Rippon
The figures are not available for individual years. Efficiency in the arrestment of dust is normally measured by the "slip"; that is, the amount of dust escaping to the atmosphere. With recently installed precipitators this represents on average 0.2 per cent. of the cement made in the kiln; it has risen on occasion to an average of 0.8 per cent. with the older units,
THAMES-SIDE CEMENT WORKS DATE OF INSTALLATION OF ELECTROSTATIC PRECIPITATORS (1) (2) (3) Date Number of existing precipitators which were installed in the years mentioned in column (1) Remarks 1934–39 … 16 Since the war 12 of these precipitators have been wholly or partially rebuilt and/or undergone a major overhaul, as detailed below. 1949 … 3 One of these precipitators underwent a major overhaul during 1957. 1951 … 1 This precipitator underwent a major overhaul during 1957. 1952 … 1 This precipitator underwent a major overhaul during 1957. 1953 … Nil 3 pre-war precipitators given major overhaul and partly rebuilt. 1954 … Nil 3 pre-war precipitators given major overhaul and partly rebuilt. 1955 … 2 3 pre-war precipitators given major overhaul. 1956 … Nil One pre-war precipitator rebuilt. 1957 … Nil One pre-war precipitator rebuilt. 1959 … 1 — 1960 … 3 — 1961 … Nil One pre-war precipitator rebuilt and enlarged. 1962 … — One pre-war precipitator being replaced by a new one. At one kiln pre-war precipitation plant to be overhauled and partially rebuilt so as to double its capacity.