Abstract: A process for removing contaminants from large volumes of wastewater is disclosed. The process involves treating a wastewater stream containing the contaminant with a coagulant that reacts with the contaminant to form a particulate or aggregate of particulates having a size greater than 10 &mgr;m. The treated wastewater is passed through a microfiltration membrane having a pore size in the range from 0.5 &mgr;m to 10 &mgr;m at low pressure (less than 20 psig) to remove the contaminant. Under such conditions, the treated wastewater flux rate is greater than 200 gallons per square foot of membrane per day (“GFD”), and typically from 200 to 1500 GFD.

Abstract: A process and system for removing heavy metals, fluoride, silica and other contaminants from large volumes of wastewater is disclosed. In the process, a wastewater stream containing the contaminant is treated with a chemical coagulant to create a particle having a diameter greater than 5 microns. Treated wastewater is passed through a microfiltration membrane which physically separates the metal contaminant particle from the wastewater. Commercially available microfiltration membranes having a pore size from 0.5 micron to 5 microns may be used. The treated wastewater flow rate through the microfiltration membranes can range from 700 gallons per square foot of membrane per day (“GFD”) to 1500 GFD. Solids are removed from the membrane surface by periodically backflushing the micro-filtration membranes and draining the filtration vessel within which the membranes are located. The dislodged solid material within the filtration vessel is flushed into a holding tank for further processing of the solids.

Abstract: A process and system for removing silica from large volumes of wastewater is disclosed. In the process, a wastewater stream containing silica is treated with a chemical coagulant, such as a epichlorohydrin/dimethylamine polymer, to create spherical particles which agglomerate into clusters having a diameter greater than 5 microns. Treated wastewater is passed through a microfiltration membrane which physically separates the silica contaminant particle from the wastewater. Commercially available microfiltration membranes having a pore size from 0.5 micron to 5 microns may be used. The treated wastewater flow rate through the microfiltration membranes can range from 150 gallons per square foot of membrane per day ("GFD") to 600 GFD. Solids are removed from the membrane surface by periodically backflushing the microfiltration membranes and draining solids at timed intervals from the filtration vessel within which the membranes are located.

Abstract: A process and system for removing heavy metals, fluoride, silica and other contaminants from large volumes of wastewater is disclosed. In the process, a wastewater stream containing the contaminant is treated with a chemical coagulant to create a particle having a diameter greater than 5 microns. Treated wastewater is passed through a microfiltration membrane which physically separates the metal contaminant particle from the wastewater. Commercially available microfiltration membranes having a pore size from 0.5 micron to 5 microns may be used. The treated wastewater flow rate through the microfiltration membranes can range from 700 gallons per square foot of membrane per day ("GFD") to 1500 GFD. Solids are removed from the membrane surface by periodically backflushing the microfiltration membranes and draining the filtration vessel within which the membranes are located. The dislodged solid material within the filtration vessel is flushed into a holding tank for further processing of the solids.

Abstract: A process and system for removing heavy metals, fluoride, silica and other contaminants from large volumes of wastewater is disclosed. In the process, a wastewater stream containing the contaminant is treated with a chemical coagulant to create a particle having a diameter greater than 5 microns. Treated wastewater is passed through a microfiltration membrane which physically separates the metal contaminant particle from the wastewater. Commercially available microfiltration membranes having a pore size from 0.5 micron to 5 microns may be used. The treated wastewater flow rate through the microfiltration membranes can range from 700 gallons per square foot of membrane per day ("GFD") to 1500 GFD. Solids are removed from the membrane surface by periodically backflushing the microfiltration membranes and draining the filtration vessel within which the membranes are located. The dislodged solid material within the filtration vessel is flushed into a holding tank for further processing of the solids.

Abstract: A process and system for separating solids from concentration soda ash solution is disclosed. In the process, a soda ash solution feed stream containing solids and other impurities is treated with a chemical coagulant to create solid particles having a diameter greater than 5 microns. Treated feed stream is passed through a microfiltration membrane which physically separates the solids from the soda ash solution. Commercially available microfiltration membranes having a pore size from 0.5 micron to 5 microns may be used. Solids are removed from the membrane surface by periodically backflushing the microfiltration membranes and draining the filter vessel within which the membranes are located. The dislodged solid material within the filter vessel is flushed removed from the filter vessel for further processing or disposal.