Use of digital computer in design of diatomite filtration plants

Optimum Design and Operation of Diatomite Filtration Plants

“…For any septum, Hp=qY~w/g . For a cylindrical septum, Hc= R;uln (1+ R~~2X) (2) L='>/Ro2+R.q,x-R8. (3) (1)…”

Comparison of Commercial Filter Aids

“…Research and Development Agency (ERDA), and EPA has been formed to evaluate radioactive waste management and disposal, thus supplementing pre viously implemented regulations. 5. The Safe Drinking Water Act of 1974 (PL 93-523) requires the regulation of underground injection that may endanger underground drinking-water sources.…”

Prediction of filter life by measurement of cake resistance

“…The significant difference between diatomite filtration and precoat carbon filtration is that in the former diatomite filter aid is added to the influent water in order to form a porous cake that is essentially incompressible. Suspended impurities in raw waters used in municipal and in individual small water supplies, however, almost invariably form com pressible filter calces (9).…”

“…The net force on the total mass in the differential distance, dx, is given by: (9) This net force equals the product of the mass within dx (includes both the liquid and the solid) and the acceleration.…”

“…The porous material which removes the suspended solids from the water and upon whose surface the filter cake forms is commonly referred to as the filter medium. In the filtra tion of water supplies, sand, carbon and diatomaceous earth are the three mostly used filter media, sand being the most common for filtration of municipal supplies (9). When the filter medium is of a relatively small particle size, a sur face filter cake is formed soon after filtration begins because practically all the solids are retained at the sur face of the filter media.…”