Contamination removal system employing filtration and plural ultraviolet and chemical treatment steps and treatment mode controller

An improved filtration process for removing contaminants from a contaminated liquid comprising the following steps:

• (a) operating an apparatus comprising a piping system including an influent liquid pipe, effluent discharge pipes, a waste drain, and process pipes, an ultraviolet pretreatment means, a chemical feed system, a pump means, a process tank, a pressure filter means including reactive granular filter media and a filter septum, an ultraviolet post-treatment means, and a central flow control means in a filtration mode,
• (b) pumping the contaminated liquid to said influent liquid pipe of said apparatus,
• (c) disinfecting the contaminated liquid by said ultraviolet pretreatment means, as needed, and producing an ultraviolet pretreated liquid,
• feeding a chemical selected from the group consisting of oxine, hypochlorite, peroxide and permanganate, or combinations thereof, as needed, to the ultraviolet pretreated liquid for chemical pretreatment and producing an ultraviolet and/or chemical pretreated liquid,
• (e) pumping the ultraviolet and/or chemical pretreated liquid to said central flow control means to said pressure filter means which comprises reactive granular filter media and a filter septum,
• (f) filtering the ultraviolet and/or chemical pretreated liquid by said reactive granular filter media supported by said filter septum inside said pressure filter means for removal of suspended, dissolved, living and non-living contaminants, and producing a filter effluent and a concentrate,
• (g) periodically discharging a portion of said concentrate from said pressure filter means though an on/off valve during a prolonged filtration operation,
• (h) discharging the filter effluent from said pressure filter means through said central flow control means to said effluent discharge pipe where the filter effluent is treated by the ultraviolet post-treatment means, and producing a post-treated effluent or a product liquid,
• (i) periodically turning said central flow control means manually or automatically from said filtration mode to a backwash mode for backwashing said pressure filter means at a liquid flow direction opposite to that of the filtration mode using the ultraviolet and/or chemical pretreated liquid and producing, then discharging a backwash wastewater from said pressure filter and said central flow control means to said waste drain for disposal,
• (j) turning said central flow control means manually or automatically from any previous operational mode to a rinse mode for rinsing said pressure filter means at a liquid flow direction identical to that of the filtration mode with said ultraviolet and/or chemical pretreated liquid and producing, then discharging a rinse wastewater from said pressure filter means and said central flow control means to said waste drain for disposal,
• (k) turning said central flow control means manually or automatically from said rinse mode to the filtration mode again for the filtration operation, for producing another filter effluent and another concentrate, and repeating steps (a) through (h),
• (l) turning said central flow control means manually or automatically from any previous operational mode to a bypass mode, allowing the ultraviolet pretreated liquid to bypass said pressure filter means and to be post-treated by said ultraviolet post-treatment means for producing a non-filtered but disinfected product liquid,
• (m) periodically turning said central flow control means manually or automatically from any previous operational mode to a flushing mode for flushing the influent liquid pipe and the ports of said central flow control means and producing, then discharging a flushing wastewater to said waste drain for disposal,
• (n) manually or automatically turning said central flow control means from any previous operational mode to a preparation mode for preparing a chemical solution in said process tank, using said contaminated liquid and chemical from said chemical feed system,
• (o) turning said central flow control means manually or automatically from any previous operational mode to a recirculation mode for recycling said chemical solution the entire apparatus to regenerate said reactive granular filter media without discharging said product liquid or said wastewater,
• (p) turning said central flow control means manually or automatically from any previous operational mode to a first precoat mode for precoating said septum with said reactive granular filter media inside said pressure filter means by recirculation of the effluent of said process tank and said reactive granular filter media from said chemical feed system,
• (q) turning aid central flow control means manually or automatically from any previous operational mode to a second precoat mode for continuously precoating said septum with said reactive granular filter media inside said pressure filter means with said contaminated liquid and said reactive granular filter media from said chemical feed system, and continuously discharging a wastewater to said waste drain, and
• (r) turning said central flow control means manually or automatically from either said first precoat mode or said second precoat mode to the rinse mode for rinsing and then to the filtration mode for normal filtration operation and producing the product liquid.