| 摘要 |
<p>Waste water effluent from online production machinery and/or clean-off water from shut-down machinery is deposited in a settling tank in which the solids settle out. Water, relatively clear of the solids, is returned to the production plant. A slurry containing a high concentration of these solids is, depending on the percentage of solids, either returned to the production machinery via a slurry tank or returned to the settling tank for further concentration. The degree of concentration of solids in the slurry tank is carefully controlled in order to permit the addition of these otherwise wasted solids to the virgin asbestos-cement slurry in the various production machineries. This addition of the otherwise wasted solids is carefully monitored at each of the production machinery installations in order to provide proper quality control of the product produced thereby. This system may further include an effluent level sensor in the settling tank in order to optimize the clarity of the clean water return as well as a pH control system which can be used to aid in precipitating out the various dissolved solids, and to chemically condition the various fluids in the effluent return system, resulting in improved quality control of the asbestos-cement end product.</p> |
