Abstract: A method and apparatus for processing waste streams wherein a slipstream is formed on the upstream side of an ultrafiltration membrane (120) to carry collected and concentrated filter reject to a microfilter (170) via a slipstream through a conduit (155) at a very low flux through the microfilter. The low flux gives the particles in this stream a chance to interact and thus form an irregular matrix that itself helps to trap particles. The effluent from this matrix and microfilter is returned upstream of the ultrafiltration membrane via a conduit (165) to be repeatedly collected and concentrated. The suspended solids removed from the reject stream and microfilter may then be disposed of directly without further processing. For metal ions, the removal efficiency of ultrafiltration membrane can be improved by injecting sulfide compounds or other compounds upstream of ultrafiltration membrane.

Abstract: A system and method for removing and collecting particulate from a water-filled tank using a filter and a pump wherein the pump operates at low flow rate to maintain only a small pressure drop across the filter low. By maintaining a small pressure drop, particulate agglomeates and can load the filter to a greater extent than when the flow rate is higher. The filter may then be crushed and placed into a disposal container for disposal. In an alternate embodiment, the particles can be accumulated in several mesh filters operating at a higher flow rate and then, as each filter is loaded, the filtrate can be back flushed to a second filter operating at low flow rate. The first filters can be repeatedly reused and the second filters can be crushed and placed in a disposal container.