CA2800816C

CA2800816C - Water integration of domestic effluent treatment and coker processing water

Info

Publication number: CA2800816C
Application number: CA2800816A
Authority: CA
Inventors: Rodney Guest; Randy Young
Original assignee: Suncor Energy Inc
Current assignee: Suncor Energy Inc
Priority date: 2012-12-21
Filing date: 2012-12-21
Publication date: 2019-09-24
Anticipated expiration: 2032-12-21
Also published as: CA2800816A1

Abstract

A process and system for integrating a domestic effluent treatment operation with a hydrocarbon coking operation. The process and system use domestic effluent water as a source of coker processing water. The process includes retrieving from the domestic effluent treatment operation a domestic effluent water including pathogens. The domestic effluent water is pre-treated to reduce a concentration of pathogens therein, to produce a pre-treated water stream. The pre-treated water stream may be supplied to a coker unit as coker quench water to quench the coker unit and produce a pathogen depleted spent quench water.

Description

, , WATER INTEGRATION OF DOMESTIC EFFLUENT TREATMENT
AND COKER PROCESSING WATER
TECHNICAL FIELD
The present invention relates to the treatment of domestic effluent and coker processing water.
BACKGROUND
Domestic effluent treatment systems may be designed to reduce the concentration of various compounds before discharging the treated water.
Domestic effluent may be treated in a treatment system that includes one or more ponds, which may include a primary lagoon followed by a polishing pond.
Domestic effluent can be treated for reduction of organic compounds, inorganic pollutants, as well as suspended and dissolved solids, to reduce biochemical oxygen demand (BOD), chemical oxygen demand (COD), pathogens and total suspended solids (TSS), for example. Domestic effluent treatment systems can employ microbial, filtering and settling mechanisms to degrade or reduce the concentration of certain compounds.
Bitumen or heavy hydrocarbon upgrading facilities often include coker units that enable delayed coking of feedstocks. Coker units require a relatively large quantity of water for certain steps in the coking process, e.g., coke quenching water and coke cutting water. Coke quenching water is used to cool the coker drums after the high temperature thermal cracking of hydrocarbon feedstock.
When the petroleum coke is at a suitable temperature after cooling, coke cutting water is used to remove petroleum coke that has deposited within the coker drums from the thermal cracking.
Water for use in coker units has typically relied on nearby natural water sources such as rivers, which can have environmental and other drawbacks.
SUMMARY
Processes, systems, and techniques for integrating a domestic effluent treatment operation with a hydrocarbon coking operation are described.
There is provided a process for integrating a domestic effluent treatment operation with a hydrocarbon coking operation. The process includes retrieving

2 from the domestic effluent treatment operation a domestic effluent water including pathogens; pre-treating the domestic effluent water to reduce a concentration of pathogens therein, to produce a pre-treated water stream; and supplying the pre-treated water stream to a coker unit as coker quench water to quench the coker unit and produce a pathogen depleted spent quench water.
The step of pre-treating may include ultraviolet (UV) treatment of the domestic effluent water.
The process may include, prior to the step of pre-treating, the step of clarifying the domestic effluent water to increase the ultraviolet transmittance (UVT) thereof.
The step of clarifying may be performed so as to increase the UVT of the domestic effluent water above 40%. The step of clarifying may be performed so as to reduce a concentration of algae in the domestic effluent water. The step of clarifying may include covering at least part of the domestic effluent treatment operation in order to reduce or prevent exposure to sunlight and thereby inhibit algae growth.
The process may also include measuring the UVT of the domestic effluent water prior to the step of pre-treating, and, in response to a UVT measurement exceeding a pre-determined threshold, reducing energy input into the UV
treatment.
The step of clarifying may include filtering and/or chemical flocculation. The filtering may include pressure-filtering and/or providing a plurality of filters arranged in series. The step of pre-treating may be performed proximate to the domestic effluent treatment operation.
The domestic effluent treatment operation may include primary treatment of source domestic effluent in a lagoon, to produce a primary effluent water, and polishing treatment of the primary effluent water in a polishing pond, to produce the domestic effluent water.
The step of retrieving the domestic effluent water may include providing a retrieval assembly for retrieving the domestic effluent water from the polishing pond.
The step of retrieving the domestic effluent water may include periodically pumping the domestic effluent water out of the polishing pond at a periodic retrieval flowrate that is greater than an inflow rate of the primary effluent water

3 into the polishing pond, and periodically stopping the pumping for a shut-off time period.
The periodic retrieval flowrate and the shut-off time period may be provided such that an overall retrieval outflow from the domestic effluent water is generally equal to inflow of primary effluent water into the polishing pond. The periodic retrieval flowrate may be between 2 and 8 times greater than the inflow rate of the primary effluent water into the polishing pond. The process may include covering the polishing pond with a floating ball cover to inhibit growth of algae therein.
The process may include controlling a level of the polishing pond around a pre-determined value. The step of controlling the level of the polishing pond may include measuring the level of the polishing pond. In response to a level measurement being less than a first pre-determined threshold level, at least a portion of the domestic effluent water that is retrieved from the polishing pond may be recycled back into the polishing pond, or retrieval of the domestic effluent water from the polishing pond may be stopped, or the retrieval of the domestic effluent water from the polishing pond may be reduced. In response to the level measurement being greater than a second pre-determined threshold level, retrieval of the domestic effluent water from the polishing pond may be increased, by increasing retrieval rate and/or retrieval duration, or recycled water back into the polishing pond may be reduced, by storing and/or discharging to alternative containment facilities.
The step of retrieving the domestic effluent water may further include periodically pumping the domestic effluent water out of the domestic effluent treatment operation at a periodic retrieval flowrate that is greater than an inflow rate into the domestic effluent treatment operation, and periodically stopping the pumping for a shut-off time period.
The periodic retrieval flowrate and the shut-off time period may be provided such that an overall retrieval outflow from the domestic effluent treatment operation is generally equal to inflow into the domestic effluent treatment operation. The periodic retrieval flowrate may be between 2 and 8 times greater than the inflow rate into the domestic effluent treatment operation.
The step of retrieving the domestic effluent water may further include continuously pumping the domestic effluent water out of the domestic effluent treatment

4 operation at a generally constant retrieval flowrate, the generally constant retrieval flowrate being substantially similar to an inflow rate into the domestic effluent treatment operation.
The process may include exposing all of the pre-treated water stream to temperatures of at least 70 C for at least 7 minutes in the coker unit, thereby destroying all pathogens present in the pre-treated water stream.
The process may include recycling at least a portion of the pathogen depleted spent quench water as part of the coker quench water.
The hydrocarbon coking operation may receive oil sands bitumen as a feedstock.
The process may further include diverting excess pre-treated water stream from the coker-unit upon detection that a flow rate of the pre-treated water stream entering the coker unit exceeds a capacity of the coker unit.
There is also provided a system for integrating a domestic effluent treatment operation with a hydrocarbon coking operation. The system includes a retrieval assembly for retrieving from the domestic effluent treatment operation a domestic effluent water including pathogens, a pre-treatment unit in fluid communication with the retrieval assembly configured for receiving and pre-treating the domestic effluent water to reduce a concentration of pathogens therein, to produce a pre-treated water stream, and a supply assembly in fluid communication with the pre-treatment unit for receiving the pre-treated water stream and supplying the same to a coker unit as coker quench water to quench the coker unit.
The pre-treatment unit may include an ultraviolet (UV) treatment unit. The UV
treatment unit may include multiple UV reactors.
The system may include a clarifying device for clarifying the domestic effluent water to increase the ultraviolet transmittance (UVT) thereof prior to introduction into the UV treatment unit. The clarifying device may be configured to increase the UVT of the domestic effluent water above 40%. The clarifying device may be configured to reduce a concentration of algae in the domestic effluent water.
The clarifying device may include a covering deployed over at least part of the domestic effluent treatment operation in order to reduce or prevent exposure to sunlight and thereby inhibit algae growth. The covering may include a floating ball covering.

The system may further include a UVT measurement device for measuring the UVT of the domestic effluent water prior to the UV treatment unit, wherein the UV
treatment unit is configured such that, in response to a UVT measurement exceeding a pre-determined threshold, energy input is reduced.

5 The clarifying device may include a filtering unit. The filtering unit may include a pressure-filtering device and/or a multi-filter device having a plurality of filters arranged in series. The clarifying device may include a chemical flocculation unit.
The pre-treatment unit may be located proximate to the domestic effluent treatment operation. The domestic effluent treatment operation may include a primary treatment lagoon for treating source domestic effluent, to produce a primary effluent water, and a polishing pond for further treating the primary effluent water, to produce the domestic effluent water.
The retrieval assembly may include an inlet that is configured and located in fluid communication with the polishing pond.
The retrieval assembly may further include a retrieval controller for controlling flowrates therein.
The retrieval controller may be configured so as to enable periodic pumping of the domestic effluent water out of the polishing pond at a periodic retrieval flowrate that is greater than an inflow rate of the primary effluent water into the polishing pond, and periodical stopping of the pumping for a shut-off time period.
The retrieval controller may be configured to provide the periodic retrieval flowrate and the shut-off time period such that an overall retrieval outflow of the domestic effluent water is generally equal to inflow of primary effluent water into the polishing pond.
The retrieval controller may be configured such that the periodic retrieval flowrate is between 2 and 8 times greater than the inflow rate of the primary effluent water into the polishing pond.
The system may further include a floating ball covering provided on a surface of the polishing pond to inhibit growth of algae therein.
The system may further include a level controller for controlling a level of the polishing pond around a pre-determined value.

6 A level measurement device may be provided in the polishing pond for measuring the level of the polishing pond. The level controller may be configured to: in response to a level measurement being less than a first pre-determined threshold level, recycle at least a portion of the domestic effluent water that is retrieved from the polishing pond back into the polishing pond; or stop retrieval of the domestic effluent water from the polishing pond; or reduce the retrieval of the domestic effluent water from the polishing pond. In response to the level measurement being greater than a second pre-determined threshold level, the level controller may be configured to: increase retrieval of the domestic effluent water from the polishing pond, by increasing retrieval rate and/or retrieval duration; or reduce recycled water back into the polishing pond, by storing and/or discharging to alternative containment facilities.
The supply assembly and the hydrocarbon coking operation may be configured and operated for exposing all of the pre-treated water stream to temperatures of at least 70 C for at least 7 minutes in the coker unit, thereby destroying all pathogens present in the pre-treated water stream.
The system may further include a quench water recycle line for recycling at least a portion of the pathogen depleted spent quench water as part of the coker quench water.
The system may further include a bypass system for diverting excess pre-treated water stream from the coker-unit upon detection that a flow rate of the pre-treated water stream entering the coker unit exceeds a capacity of the coker unit, There is also provided a process for integrating a domestic effluent treatment operation with a hydrocarbon coking operation. The process includes:
retrieving water from a pond in a domestic effluent treatment operation, the pond receiving an inflow of effluent for treatment, wherein the retrieving comprises cyclically pumping an outflow of the water from the pond, wherein each pumping cycle provides a flowrate that is greater than the inflow rate of the effluent into the pond;
and providing at least a portion of the outflow of the water retrieved from the pond as coker quench water to a hydrocarbon coking operation and using the coker quench water in a quenching cycle.
There is also provided a process for integrating a domestic effluent treatment operation with a hydrocarbon coking operation. The process includes retrieving

7 domestic effluent water from the domestic effluent treatment operation. The domestic effluent treatment operation includes treating domestic effluent in a primary lagoon to produce a primary effluent water; and treating the primary effluent water in a polishing pond to produce the domestic effluent water. The retrieving includes cyclically pumping an outflow of the domestic effluent water.
Each pumping cycle provides: a pumping stage providing a retrieval flowrate that is greater than an inflow rate of the primary effluent water into the polishing pond;
and a downtime stage providing sufficient time so that each pumping cycle retrieves an outflow of the domestic effluent water that is generally equivalent with the inflow of the primary effluent water. The process also includes providing at least a portion of the domestic effluent water retrieved from the polishing pond as coker quench water to a hydrocarbon coking operation and using the coker quench water in a quenching cycle.
BRIEF DESCRIPTION OF DRAWINGS
Fig 1 is a block flow diagram including a domestic effluent treatment operation and a hydrocarbon coking operation with water integration.
Fig 2 is another block flow diagram with water integration.
Fig 3 is a graph of quench water flow versus time.
Fig 4 is a process flowchart.
Fig 5 is another block flow diagram including a hydrocarbon coking operation.
DETAILED DESCRIPTION
Techniques described herein provide water integration between a domestic effluent treatment operation and a hydrocarbon coking operation.
The water integration techniques include the use of domestic effluent water as a source of coker processing water, e.g., quench water and/or cutting water, in a hydrocarbon coking operation. Such techniques may facilitate leveraging the water requirements of coker quench cycles to reduce the need for increasing capacity at a domestic effluent treatment operation. For example, coker quenching requires water in high quantity but of lower quality than other hydrocarbon extraction or processing operations, and water derived from a

8 domestic effluent treatment operation can be efficiently used to meet coker quenching requirements.
Referring to Fig 1, a water integration system 10 includes a domestic effluent treatment operation 12 and a hydrocarbon coking operation 14. In the implementation shown and discussed, domestic effluent water is obtained from the domestic effluent treatment operation 12 and provided to the hydrocarbon coking operation 14 for use as coker quench water. It should be understood that in other implementations, the domestic effluent treatment water can be used as coker cutting water.
Referring still to Fig 1, in some implementations the domestic effluent treatment operation 12 may include a primary lagoon 16 for receiving raw domestic effluent 18 or a stream derived from raw domestic effluent. The primary lagoon may operate as a continuous flow aerated lagoon system. The raw domestic effluent 18 supplied to the primary lagoon 16 may form a bottom layer including settled solids, a top layer including lighter floating solids and a middle layer including mainly primary effluent water 20. The primary effluent water 20 in the lagoon contains bacteria that biodegrade various pollutants, notably organic material, present in the domestic effluent. The primary effluent water 20 may thus be subject to both anaerobic and aerobic water treatment. Under anaerobic treatment, bacteria that are not oxygen dependent convert certain organic pollutants in the water, as the bacteria can act under low oxygen conditions.
The anaerobic treatment alone does not provide a complete conversion of the organic pollutants and is followed by an aerobic treatment. Under aerobic treatment, bacteria that are oxygen dependent continue the conversion of certain organic pollutants in the water. Thus, there are several types of micro-organisms that are active in the primary lagoon 16 for biodegrading different substrates considered as pollutants. Some of the micro-organisms are considered as pathogenic in the sense that sufficient contact with flora, fauna and/or humans can cause physiological problems. The primary effluent water 20 includes pathogens along with other micro-organisms and other pollutants that may be subjected to further downstream treatment. One technique to measure the concentration of pathogens in effluent water is to measure a concentration of coliform bacteria in the water.
Coliform bacteria are not generally pathogenic. However, the presence of coliform bacteria is used as an indicator of the overall concentration of pathogens in water =

9 effluent, as coliform bacteria are easy to culture from samples that are used for water quality analysis The primary effluent water 20 may then be supplied to a subsequent treatment system, which may include a polishing system 22. The polishing system 22 may include one or more polishing ponds depending on the design of the domestic effluent treatment operation 12. The polishing system 22 contributes to the removal and degradation of additional pollutants, such as pathogens and some solids, to produce domestic effluent water 24. The domestic effluent water 24 still includes some remaining pollutants such as pathogens, suspended solids and dissolved solids. If the effluent water is not recycled and is discharged into the environment as a discharge stream 25, such as an adjacent river or other body of water, a concentration of pollutants the domestic effluent water 24 is controlled according to local regulatory limits. One such regulatory limit is the concentration of coliform bacteria present in the effluent water. An example of a regulatory limit is to have coliform bacteria concentrations in the effluent water below 200 cfu/100 ml (colony-forming units per hundred milliliters).
, In certain scenarios, the above-described domestic effluent water treatment systems, including the lagoon and polishing pond, are sufficient to reduce the concentration of pathogens in the water within a target regulatory limit prior to discharge into the environment. One such scenario may occur during operation of the treatment systems in cold months, when the treatment systems allow a very low level of pathogen survival. However, in warmer months, the levels of pathogen survival are much higher. Therefore, water derived from the domestic effluent treatment operation 12 is supplied to a pre-treatment unit 28 in order to further reduce a concentration of the pathogens in the effluent water, and thus control the level of pathogens in the effluent water across a more complete range of operational conditions. The pre-treatment unit 28 brings the pathogen levels to near or below local regulatory limits, either for use in coker unit operations or for discharge into public waterways.
In certain scenarios, if the cokers cannot handle the volume of domestic wastewater within their normal operational cycles, some arrangement for diversion of excess flow can be made. The liquid concentrations of coliform bacteria in domestic effluent water that is routed to a by-pass of the coker unit may not be sufficiently low for direct release to a public waterway, if not adequately disinfected by the pre-treatment unit. However, the stream from the pre-treatment unit can be sent to a storage lagoon and be diluted with water from other sources. This dilution the stream obtains from its progression into its final storage lagoon is designed such that the final concentration of colifornn bacteria is lowered to levels that are at least an order of magnitude lower than the exit from 5 the pre-treatment unit. Thus, with any further dilution into the final public waterway, the coliform bacteria concentrations can be adequately below target local regulatory limits.
Referring to Fig. 1, the water integration technique detailed below recycles water produced by domestic effluent treatment operations 12 for use as coker quench

10 water. Recycling as coker quench water can reduce diverting domestic effluent water to other effluent or tailings containment systems, or direct discharge to public waterways. Recycling can also replace river water or other cold process water as a quenching medium in the coker unit. Recycling can also reduce the use of API-recycle water, also used for coker unit quenching.
Referring to Fig 2, in some implementations, the domestic effluent water 24 may be retrieved from the polishing system 22 using one or more retrieval pumps 26 for supplying water toward the hydrocarbon coking operation.
Referring back to Fig 1, pre-treatment of the water prior to transferring to the hydrocarbon coking operation 14 reduces the concentration of pathogens. At least a portion of water derived from the domestic effluent treatment operation 12 is supplied to a pre-treatment unit 28 as a feed water stream 30. The feed water stream 30, thus includes the domestic effluent water 24 retrieved from the polishing system 22. The pre-treatment unit 28 is configured and operated to reduce the pathogen concentration in the feed water stream 30.
In certain scenarios, the pre-treatment reduces exposures of coker unit operators to potentially hazardous elements, such as pathogens, in proximity of coking operations, e.g., if a leak were to occur. However, at the installations housing the coker units, access to the various coker decks is restricted during the introduction of quenching water and de-heading of the cokers. Such operations lead to potential exposures to elevated levels of hydrogen sulphide or other hazardous vapours during the de-heading process. Therefore, workers on the affected coker deck areas typically employ personal protection equipment to prevent any excessive exposures. Although not specifically designed for biological aerosols or pathogens, the particle sizes relevant to these aerosols or pathogens are very

11 similar to the other dusts that are filtered by respirators. Moreover, the effluent from the pre-treatment system can be totally enclosed in a pipeline, as it proceeds through the pre-treatment unit, and then piped onward until it reaches the inlets of the coker units. Thus, exposure to pathogens in either the pre-treated effluent water or the air above it (or dissolved within) for coker unit workers during this transfer process can be minimized.
Referring to Fig 2, in some implementations, there is a domestic effluent water return stream 32 for returning a portion or all of the domestic effluent water 24 that is obtained from the polishing system 22. The return stream 32 is sent back into the polishing system 22 in order to bypass the pre-treatment unit 28 temporarily, e.g., during downtime or turndown operations. The return stream 32 may configured and operated to facilitate diversion of domestic effluent water back to the polishing pond 22 in certain instances, e.g., in case the UV treatment unit 28 experiences an operational upset. The return stream 32 can also provide an alternate sample point for domestic effluent water that is more readily accessible to operations and maintenance personnel.
In some implementations, there is a bypass stream 36 for bypassing a portion or all of the feed water stream 30 around the pre-treatment unit 28.
The pre-treatment unit 28 is configured and operated to decrease a concentration of pathogens in the effluent water. More regarding the pre-treatment unit 28 and related operations will be discussed further below.
A coker quench water stream 38 derived from the domestic effluent treatment facility 12 is supplied to the hydrocarbon coking facility 14. In some implementations, water sources may be combined with this coker quench water stream 38, such as industrial effluent streams 40 that may include API
separator water, and/or various water recycle streams, such as a treated spent coker water stream 42. The combined streams, which include the stream 38 derived from the domestic effluent treatment facility 12, are provided as coker quench water 44 to a coker unit 46.
Fig 3 provides an example of flowrate versus time of the coker quench water 44 introduced into a coker drum of the coker unit 46 for a given quench cycle.
Fig. 4 shows a process for utilizing water from a domestic effluent treatment operation which includes retrieving water derived from the domestic effluent ,

12 treatment operation, the water including pathogens, indicated by reference numeral 100. The water is pre-treated to reduce the pathogen content and produce a pathogen reduced water for use a coker quench water, indicated by reference numeral 102. The coker quench water is transferred to a hydrocarbon coking operation and using the coker quench water in a quenching cycle, indicated by reference numeral 104.
In some implementations, a process integrating water between a domestic effluent treatment operation and a hydrocarbon coking operation includes retrieving water from a pond in a domestic effluent treatment operation, the pond receiving an inflow of effluent for treatment. The retrieving can include cyclically pumping an outflow of the water from the pond, wherein each pumping cycle provides a flowrate that is greater than the inflow rate of the effluent into the pond.
At least a portion of the outflow of the water retrieved from the pond is provided as coker quench water to a hydrocarbon coking operation and using the coker quench water in a quenching cycle.
In some implementations, a process integrating water between a domestic effluent treatment operation and a hydrocarbon coking operation includes retrieving domestic effluent water from the domestic effluent treatment operation.
The domestic effluent treatment operation includes treating domestic effluent in a primary lagoon to produce a primary effluent water, and treating the primary effluent water in a polishing pond to produce the domestic effluent water. The retrieving can include cyclically pumping an oufflow of the domestic effluent water.
Each pumping cycle provides a pumping stage providing a retrieval flowrate that is greater than an inflow rate of the primary effluent water into the polishing pond;
and a downtime stage providing sufficient time so that each pumping cycle retrieves an oufflow of the domestic effluent water that is generally equivalent with the inflow of the primary effluent water. At least a portion of the domestic effluent water retrieved from the polishing pond is provided as coker quench water to a hydrocarbon coking operation and using the coker quench water in a quenching cycle.
Various techniques and implementations will be described in more detail below, in relation to particular parts of the system.

13 Domestic effluent treatment operation and water retrieval The domestic effluent treatment operation 12 may be implemented in a variety of ways. The incoming effluent 18 may be from a sewage system associated with a hydrocarbon processing facility, such as a bitumen mining, extraction and upgrading plant. The domestic effluent 18 may come from working personnel at the bitumen extraction and upgrading facility, camps or domiciles for the working personnel and/or household sewage from communities.
In some implementations, the domestic effluent treatment operation 12 may be proximate to the coking operation 14, thus reducing transportation infrastructure and energy for supplying the domestic effluent water 24 as coker quench water.
Alternatively, the domestic effluent treatment operation 12 may be relatively remote from the coking operation 14, thus requiring additional fluid transportation configurations. Of course, the domestic effluent water used as coker quench water may be a mixture of multiple streams from different domestic effluent water sources that may be proximate or remote from the coking operation 14.
As will be discussed further below, if the domestic effluent treatment operation 12 is relatively remote with respect to the coking operation 14, the water may be handled and subjected to certain pre-treatment steps. For example, in some implementations the domestic effluent treatment operation 12 and the coking operation 14 may be located in different locations within a bitumen mining, extraction and upgrading operation, with a given terrain separating the two operations. The separating terrain may be occupied by various installations, infrastructure and working personnel associated with the bitumen mining, extraction and upgrading operation. In such scenarios, a fluid transportation assembly 48 may be provided to retrieve the water, transport the water across the terrain, and supply the water to the coking operation.
Referring to Fig 1, domestic effluent water 24 retrieved from a polishing pond typically has a concentration of pathogens. In some implementations, the pre-treatment system 28 is provided relatively near to the polishing pond 22 to reduce the pathogen concentration proximate the domestic effluent treatment operation 12 such that the resulting fluid can be transported across various terrains or distances in the bitumen mining, extraction and upgrading plant, which can cover a large area. Pre-treatment proximate the domestic effluent treatment operation ,

14 , 12 can enhance protection of the environment and personnel, for example around the fluid transportation assembly and near any operator sites prior to quenching.
Referring to Fig 1, in some implementations, a lagoon outlet flow meter 50 may be provided when water fed to the polishing pond comes from a primary lagoon 16.
The flow meter may be provided so as to monitor and totalize fluid flow from the lagoon 16 to the polishing pond 22. The flow can be monitored on a regular basis (e.g. daily) to track re-use water demand, for example. The flow can be monitored to assess whether excess effluent water 20 from the lagoon 16 is being fed to the polishing pond 22, for example to determine whether additional flowrate of water should be retrieved from the domestic effluent treatment operation 12 for use as coker quench water in order to reduce or maintain the discharge of domestic effluent water 24 to effluent containment systems, tailings containment systems and/or back into a natural water source.
Referring to Fig 1, in some implementations, the polishing pond 22 may be maintained at a minimum level to prevent excessive odours from developing.
Various units may be put in place to maintain the level of the pond relatively constant. For example, a continuous level indicator may be provided in the polishing pond 22. The indicator may include a pressure sensor for hydrostatic level measurement, which may be placed on the bottom of the polishing pond to measure its level. Instrument cables can be run through a protective sleeve to guard against ice breakage. The polishing pond level may rise or fall due to higher or lower than average inflow, storm water ingress, pond seepage and/or evaporation. Operators can manually cycle a pump to reset the level or change the time sequence to increase or decrease the batch flow of effluent water 24 out of the polishing pond 22. This can provide flexibility to operators to maintain the polishing pond level as needed. When the domestic effluent water flow is turned down or off, a corresponding portion of the coker quench water may come from other sources, such as existing API separator pond water 40 and/or other water sources.
Referring to Fig 2, in some implementations, should the polishing pond level reach its maximum when there is no active quenching process, retrieval pumps 26 can be provided with a piping connection 52 to allow the pond to be drained to static or mobile units, e.g. trucks, as a temporary measure. Fluid captured in mobile units may be transported to an effluent treatment plant, for example.

, Referring to Fig 1, in some implementations, the domestic effluent treatment operation 12 may also include a sump (not illustrated), which may be located at a side of the polishing pond, to recover overflow water from the polishing pond 22.
The level of water in the sump may be monitored (e.g. through a wireless 5 network) and may be controlled by starting and stopping a sump pump (not illustrated) automatically. A pressure sensor for hydrostatic level measurement may be set on the bottom of the sump to measure the level and send an output to a pump controller, which operates the pump start or stop to maintain a maximum predetermined level that should not be exceeded. Operators can monitor the level 10 and locally adjust set-points for pump start or stop on the controller.
Pre-treatment unit and related operations Referring to Fig 1, the domestic effluent water 24 that is retrieved from the domestic effluent water treatment operation 12 may be provided to a pre-treatment unit 28.

15 As described above, the domestic effluent water 24 may contain a certain concentration of pathogens. For example, the domestic effluent water 24 retrieved from the polishing pond 22 may have reduced levels of certain pollutants such as organic compounds and solids, but may still benefit from further reduction of pathogen concentration. In addition, according to testing of an example of domestic effluent water 24 retrieved from a polishing pond 22, concentrations of certain pollutants may vary depending on weather, season or other factors.
In some implementations, the pre-treatment unit includes an ultraviolet (UV) treatment unit, which may include one or more UV reactors. The UV treatment unit is configured to receive the feed water stream 30, which may be composed of various streams including at least one from the domestic effluent treatment operation 12. The UV treatment unit have lamps that provide a dose of UV light in order to deactivate pathogens in the feed water stream 30. In some scenarios, the feed water stream 30 has a UV transmittance (UVT) of at least a pre-determined UVT threshold to facilitate pathogen inactivation. UVT is a measure of the amount of light that can pass through a sample. The pre-determined UVT threshold may be 30%, 35%, 40% or 45%, for example. The pre-determined UVT threshold may be determined based on the adequate UVT to achieve effective deactivation level of pathogens.

16 In some implementations, the pre-treatment unit may alternately include any other system capable of decreasing a concentration of pathogens in the effluent water.
For example, water from the polishing pond may be subsequently treated in a long-term storage lagoon, in order to allow bacteria to further biodegrade any pathogens in the effluent water over a longer period of time and thus bring a concentration of pathogens within a target threshold.
In some implementations, the UV treatment unit includes a UV control panel having outputs to indicate status for the following: Remote lamp on-off control;
Flow interlock; Remote signals; Re-transmission of UV intensity; and Number of Off-On lamp cycles for each reactor. Control of the UV treatment system may be done locally, but the UV reactors can remain powered full-time, which may be facilitated by low-pressure, high output (LPHO) UV bulbs that can typically only be started and stopped 4 times per day, and take 4 minutes to warm up. Excessive start cycles limit lamp life. Operating the UV reactors prior to warm-up can result in a low applied UV dose.
In addition, referring to Fig 2, on the suction side of the retrieval pumps 26, an on-line UVT meter 54 may be installed. Data from this UVT meter is brought back to a programmable logic controller (PLC), to allow operators to determine whether any of the three operating UV reactors can be switched off should UVT of the domestic effluent is higher than a pre-determined UVT threshold.
Referring to Fig 2, in some implementations, the UV treatment unit 28 may also include a high temperature sensor and/or alarm. In case of an alarm, an effluent pump 26 would turn on for a time period (e.g. 5-10 seconds) to send fresh water into the UV reactors. The control panel may include a high temperature alarm, which may provide a local alarm. If high temperatures persist, the UV system may be shut down.
In some implementations, the UV treatment reactors may be based on LPHO
lamps. In a particular illustrative example, each reactor has 20 lamps, and based on polishing pond sample data, three reactors can be used to treat 300 USGPM, with a fourth reactor included as a spare. The LPHO lamps cycle on and off four times per day to prevent premature lamp failure. Because of the intermittent nature of coker quenching operations, the UV reactors can be powered at all times. The lamps may operate at about 90 C and can operate without flowing water for cooling. Each UV reactor may include double-block and bleed valving.
A

17 temperature sensor may also be provided. Upon detection of high reactor temperature, the effluent pumps may be run briefly to exchange the water in the UV reactors for fresh, colder water. Of course, various other types and configurations of UV reactors can be used.
In some implementations, UV transmittance levels may rise due to algae mitigation, e.g. by use of the floating ball cover, and the UV reactors can consequently treat higher flow rates of domestic effluent water 24, or the same flow rate could be treated to achieve greater coliform count reductions after treatment. Conversely, a provision can be made in the fluid transportation assembly 48 for installation of an additional clarifying treatment (e.g.
filtration) to compensate for UVT values lower than expected. As mentioned above, there may be an on-line UVT sensor 54 to provide water monitoring capabilities so as to adjust flow accordingly.
In the event that the domestic effluent water 24 used to provide the feed water stream 30 has a UVT below the pre-determined threshold, a clarifying treatment may be performed prior to supplying the stream to the UV treatment unit.
The clarifying treatment may include various methods. For example, the clarifying treatment may be configured for reducing algae content from the domestic effluent water 24. Increases in UVT can be due to the presence of algae.
Domestic effluent ponds typically have an abundance of nitrogen and phosphorus. High hydraulic retention times and sloped sides (e.g. 3:1 slope) of a pond can result in a high surface area to volume ratio and provide an optimal environment for the growth of algae. Algae may thrive during summer months resulting in lower UVT in the domestic effluent water 24, although as the algae begin to die off in colder seasons the algae would absorb less UV light, therefore increasing the UVT of the water 24. For example, several water samples taken from the pond during a summer to late fall period showed low UVT. The samples also showed a sudden increase in total suspended solids (TSS) in the early fall period, which is likely from algae dying off due to a drop in ambient temperature and settling in the polishing pond. Thus, the clarifying treatment may be conducted to remove algae, particularly in the summer season when algae are more abundant.
It was also observed in an experiment that lower ambient temperature resulted in lower TSS, further indicating the effect of algae in the polishing pond water.
This

18 temperature impact on TSS is somewhat counterintuitive as TSS would typically increase with lower temperature due to reduced biological activity. After a certain period, a decrease in TSS and an increase in UVT were evident. The presence of fecal coliform in the effluent also had a similar counterintuitive behavior in that fecal conform counts did not have a similar decrease due to lower temperatures until early October.
Due to the low UVT of certain domestic effluent water, UV treatment may be enhanced by subjecting the water to the clarifying treatment to increase the UVT
above the pre-determined threshold.
In some implementations, the clarifying treatment may include covering the polishing pond 22 for algae control. This may be done by providing a floating ball cover deployed on the polishing pond 22 for algae control. The floating ball cover can be formed from black coloured floating balls formed from about 6" diameter hollow polymer (e.g. HDPE) spheres and each having an orientation tab. The floating balls may be dispersed over the surface of the polishing pond 22, where they arrange themselves evenly with the orientation tabs pointing down. The tabs also help prevent rolling and bunching of the balls. Three sides of the polishing pond may have a slope to retain the balls within the pond, e.g. if moved by wind.
Extremities of the pond may be lined with a fence structure to provide further retention as balls that are blown out of the pond can hit the fence and roll back into the pond. An additional amount of balls may be added to the initial requirement of floating balls as replacement stock. The replacement stock can be placed in inventory and added to the polishing pond if wind forces balls over the extremities of the pond and they fail to return. In one example, approximately 100,000 to 150,000 of 6" outer diameter (OD) floating balls may be provided to cover the entire surface area of a polishing pond.
In some implementations, the clarifying treatment may include filtration to capture solids and restrict large particles (e.g. over 30-40 micron) that can shade light and thus reduce effectiveness of the UV treatment. Various different types of filters may be used upstream of the UV treatment unit. The filtration treatment produces a filtered stream and a waste stream. In the case of disposable filters, the waste stream would include a solid waste stream. Other filtration options could require handling and monitoring of backwash water. For some backwash water systems, a buried backwash tank may be provided and may have internal baffles to facilitate solids removal. The backwash tank can be configured to allow settlement

19 of larger solids that would be removed by a vacuum truck. Decant water may be allowed to drain back to the front end of lagoon treatment.
In some implementations, a sidestream filtration system, such as the VortisandTM
filter system may be used to provide pressure filtration with removal of solids in the 1-2 micron range. This sidestream filtration system uses centrifugal force (vortex effect) to whirl the untreated water above media (multi layers) and directs larger suspended solids on a side wall of the tank. The particles above the filter bed develop a filter cake that then traps the smaller particles. This increases the effective filter surface within the tank when compared to a conventional sand filter.
Turbulence may produce a sustained cleaning action (or cross flow filtration) that forces the suspended solids to accumulate. Contaminants trapped above the sand are removed using an automatic backwash cycle which requires less water and a shorter operating time than traditional sand filters. The turbulence allows for use of a finer filtration media that in turn allows for a smaller capture.
Conventional down flow depth filter technology can filter down to 10-15 microns in particle size whereas the sidestream filtration system can filter to 0.45 microns.
Removal down to 2 micros, consistent with removal for green algae, can be used in certain scenarios. In one example, a plurality, e.g. more than then, 36"
diameter vessels may be used. This can provide redundancy whereby one tank can stop for backwash while the other one remains in filtration mode. The size of the system could be reduced by increasing the number of backwashes per day.
In some implementations, a cartridge and disc based system can be used for filtration. One example of such a system uses 3 stages (2 disc stages and 1 cartridge stage). The process may include a roughing filter to remove large solids followed by a 20 micron filter stage. Pre-filtration stages may provide improved protection to the microfiber filters.
In one example, 2 x 3 micron microfiber filtering units are provided. These self-cleaning filters have an integral cleaning system to backwash captured solids.

The microfiber filter requires filtrate storage for flushing (1300 USG) the unit. Such a filtration device offers automated filtration and a lower level of operator intervention.
In some implementations, the clarifying treatment may include chemical treatment. For example, chemical flocculation may be used to improve UVT.
Chemical flocculation may also be used in combination with other separation , steps such as filtration as flocculation generates larger particles that are more easily removed by filtering. Chemical injection can be used to precipitate chlorophyll dissolved in the domestic effluent water, in the event that algae or chlorophyll by-products affect the UVT.
5 Turning back to the UV treatment unit 28, in some experiments the effect of applied UV dose (measured in mJ/cm2) on various pathogens was studied. There appears to be a limited increase in coliform reduction above doses of 100 MJ/cm2.
The same dose shows a 4-log reduction of MS2, a virus which is easily cultivated in laboratories and used to measure viral reduction efficacy of treatment systems, 10 which is above the reduction typical in water treatment systems.
Hydrocarbon coking operation Referring to Fig 1, the hydrocarbon coking operation 14 may include a delayed coking process, which includes an operating scheme that is generally alternating.
15 The hydrocarbon coking operation 14 may be for heavy oil or bitumen feedstocks, such as those produced in the northern Alberta oil sands.
Referring to Fig 5, the hydrocarbon coking operation 14 may have a coker unit including one or more pairs of coker drums 48a, 48b. In general, while one of the coking drums is in thermal coking operation mode, the other coking drum

20 undergoes quenching and cutting for coke cooling and removal followed by preparation for its coking stage. A first coker drum 48a may be initially heated by an adjacent drum 48b that is already in its coking stage. When the coking drum 48a reaches an adequate or pre-selected temperature (which may be nominally 900 F), it may be ready to receive a bitumen charge from the coker furnace In the operating drum 48b, the bitumen undergoes thermal cracking which yields light hydrocarbons in the form of a coking product vapour 50 and petroleum coke that remains in the coker drum. The coking product vapour 50 is sent to a fractionator (not illustrated), which can fractionates out various different hydrocarbon product streams. At this point, the operating drum 48b contains some porous bitumen and coke.
Water is then introduced into the drum 48b for quenching purposes. The quenching may include an initial stage of quench-steaming following by quench-soaking. The quench-steaming stage includes adding quench water into the coker .

21 drum at a flowrate such that the high temperature of the coker drum causes most of the quench water to be converted to steam. The resultant steam may strip additional hydrocarbons from the pores of the bitumen remaining in the coker drum. During the quench-steaming stage, the mixture of steam and effluent vapours may continue to be sent into the fractionator to continue recovering as much high value hydrocarbon products as possible. Afterwards, during the quench-soaking stage, more quenching water may be added at higher flowrates into the coker drum 48b to further reduce the temperature of the coker drum 48b and prepare the drum for coke cutting and cleaning.
For example, referring to Fig 3, each coker quenching cycle may last approximately 4 hours per coker drum. Depending on how many coker drum pairs are used in a given coking operation, quenching may be done on multiple coker drums at a time (e.g. one per pair). During the quench-steaming stage, quenching may be initiated with a flow of about 300 USGPM for about 55 minutes. Then, the quench water flow may be increased at a rate of about 7.5 USGPM/min for 85 minutes, reaching a final flow rate of about 3,200 USGPM, which may be held for an additional 50 minutes. During this time, the quench water is retained in the drum and exposed to high temperature for extended time. The retained quenching water may be retained for sufficient time to reduce the temperature of the coker drum to a pre-determined level and then the water may be released as a spent quench water stream 52. Draining spent quench water 52 from the coker drum may take several hours.
In some implementations, the domestic effluent water 38 used as coker quench water 44 may contain a concentration of pathogens. The quenching water requirements are such that the domestic effluent water may be efficiently used as coker quench water. The residual pathogens do not impair the quenching process; rather, residual pathogens may be consumed or deactivated by the quenching. For example, residual pathogens are exposed to sufficiently high-temperature conditions for sufficient time so as to deactivate the pathogens.
In a particular illustrative example, a flow of recycled domestic effluent can replace an existing API source of cooling water for the first hour of a quenching cycle for a coker unit. In such a scenario, about 19,000-21,000 gal. of domestic effluent water is used and about 79% of this water is flashed to steam. After a complete quenching cycle, top and bottom heads of the coker drums are removed to extract the coke residues. By that time, water that has not flashed during the

22 first hour will be drained below and sent to a coker spent water containment system (e,g, an API lagoon system) . About 29% of water (or - 36,000 gal.), including domestic effluent and other sources, e.g. API recycle water, is flashed over the entire cycle with a 125,000 gal. average total volume use. That means that only 21% of the 19,000-21,000 gal., or about 4200 gal., on average, survives in liquid form to be diluted with the other sources of cooling water that make up the remaining 107,000 gal.of water that is fed to the coker unit during the quenching phase. Therefore, the domestic effluent water may contain no more than about 4 % of its original concentration of any surviving pathogens.
However, based on the fact that the domestic effluent water is trapped in the coker for the remainder of the quenching cycle, there is ample time for the effluent water to be sterilized by the elevated temperature in the coker drum. Even after the remainder of the cooling domestic effluent water enters into the coker drum after the initial flashing stage, the time at which the mixture remains high enough in temperature (70-80 deg. C) to kill any bacteria, is more than 2 hours, which exceeds required conditions for the sterilization of water for food use, e.g.
between 7 minutes at 70 deg. C., and 30 minutes at 65 deg. C, or 2 hours at 60 deg. C. Consequently, any domestic effluent water entering the coker drum as quench water will be subject to complete pathogen destruction before being drained.
Pathogens have thus been eradicated from the drained quench water 52 that is released from the coker unit 46. Pathogen eradication can facilitate handling of the spent quench water 52 downstream of the quenching. Improved handling of the spent quench water 52 may include enhanced flexibility for water treatment, transportation, and recycling options into various processes that may benefit from a pathogen-deactivated water source.
Referring to Figs 1 and 2, the spent quench water stream 52 may be fed to a water treatment unit 54, which may include one or more setting basins and/or other units for removing fine solids, to produce a treated water that may be recycled as the treated spent coker water stream 42 combined with domestic effluent water 38 and optionally make-up water (shown as stream 58 in Fig 2).
A
portion 60 of the treated spent coker water stream 42 may also be supplied to other processes, holding or disposal within the bitumen mining, extraction and upgrading plant. Another portion (shown as stream 62 in Fig 1) of the treated

23 spent coker water stream 42 may be used within the coker unit 46 for purposes other than coker quenching.
In some implementations, the domestic effluent water 38 may be introduced into the coker drums at any time during the quench cycle such that the water is exposed to at least 70 C/158 F for at least 7 minutes.
Fluid retrieval, transfer and supply between units and operations Referring to Fig 1, the fluid transportation assembly 48 may be provided, configured and operated for integration between the domestic effluent treatment operation 12 and the hydrocarbon coking operation 14.
The fluid transportation assembly 48 may include a retrieval assembly for retrieving the domestic effluent water 24 from domestic effluent treatment operation 12. The retrieval assembly may include a pipeline having an inlet in fluid communication with the polishing pond 22 and an outlet in fluid communication with the pre-treatment unit 28. The inlet of the pipeline may be located in the polishing pond at location and depth to ensure retrieval of water substantially without air or settled material. The level of the polishing pond may be managed in accordance with a minimum level for submersion of the inlet.
The retrieval assembly may also include one or more retrieval pumps (shown as 26 in Fig 2) that are operatively coupled to the pipeline to enable transporting the domestic effluent water 24.
In some implementations, the retrieval pumps 26 can be sized for about 300 USGPM, TDH (total dynamic head) of 319 ft, and a suction pressure of about 102 PSIG. The effluent pumps 26 may include Variable Frequency Drives (VFDs) that can serve as motor starters for the pumps, in addition to speed control of the pumps. Speed control of the retrieval pumps 26 can facilitate operational flexibility in maintaining polishing pond levels or supplying water to the pre-treatment unit 28 and/or coker unit 46. For example, variable speed pumps can allow increasing flow into UV reactors should UVT values be favourably high, or allow diverting domestic effluent water through piping connection 52 to the trucks at a greater flow rate for polishing pond level control.
In some implementations, two or more retrieval pumps 26 may be installed to draw domestic effluent water 24 from the polishing pond 22 for transfer to a UV

24 treatment system. A controller 64, e.g. a programmable logic controller (PLC), may be operated to start and stop the retrieval pumps 26. The controller 64 may be configured such that the pumps do not start if the UV system is in shut-down, e.g. due to fault alarms. If the level of the polishing pond 22 reaches a certain low level, the controller 64 may be configured to wait for a certain time before shutoff of the retrieval pumps 26. The controller 64 may also be configured to receive an input signal (e.g. analog input signal) from a pressure transmitter 66 installed on the common discharge piping from the retrieval pumps 26. The controller 64 may be configured to shut off the two pumps if the pressure exceeds a pre-determined limit.
In some implementations, the retrieval pumps 26 may be FlowserveTM 2K3x1.5-10ARV M3 S FPD DCI effluent pumps. Sizing may be based on using one operating, and one spare pump. The pumps may include a 3" OD horizontal suction and a 1.5" OD vertical discharge. Both suction and discharge connections may be 150# flat-faced, neoprene gaskets being provided for the pump connections.
In some implementations, instead of having a VFD to operate the retrieval pumps 26, a single speed motor starter may be used. Such a device allows operation staff to modulate the pump flow to match lagoon inflow and quenching operations.
The fluid transportation assembly 48 may include a supply assembly for supplying the water 38 to the hydrocarbon coking operation 14. The supply assembly may include a pipeline having an inlet in fluid communication with the pre-treatment unit 28 for receiving the treated water, and an outlet in fluid communication with the coker unit 46. The outlet of the supply assembly may be coupled to an existing quench water injection system associated with the coker drums. The supply assembly may include various other units such as holding or surge tanks (not illustrated), connections for combining the domestic effluent derived water 38 with other sources of water, and recycle lines. For example, there may be a recycle line 68 for returning a portion or all of the water exiting the pre-treatment unit back into the lagoon 16. The supply assembly may also include one or more supply pumps (shown as 70 in Fig 2) that may be configured as one or more booster pumps.
In some implementations, the supply pipeline may be substantially provided buried underground. Such a buried supply pipeline can reduce lengths of piping , , for which heating elements (e.g. electrical heat tracing) re installed, reducing electricity demands, and can also increase above-ground roadway space.
Alternatively, the supply pipeline may have above-ground routing between the domestic effluent treatment operation 12 and the coking operation 14, which may 5 facilitate maintenance and monitoring.
In one scenario, the fluid transportation assembly may be provided such that retrieval flowrate of the water from the polishing pond substantially matches the inflow into the polishing pond. For an inflow into the polishing pond of about USGPM, the retrieval flow would also be about 70 USGPM. In this case, a treated 10 storage tank may be provided to balance the flow to the coking operation and provide storage capacity for interruption of re-use demand.
In some implementations, the fluid transportation assembly may be configured and operated such that frequent fluid movement occurs in the water transport components from the polishing pond until the coke quenching. For example, this 15 may be enabled by avoiding intermediate storage tanks along the fluid transportation assembly 48. Storage tanks would require additional pumps adding to the overall cost and maintenance of the system, and may also be vulnerable to re-growth and associated drawbacks. The flowrate of domestic effluent water retrieved and supplied as coker quench water may thus be coordinated with 20 transportation and pre-treatment constraints as well as inflow rates into the polishing pond.
In one scenario, the fluid transportation assembly may be provided such that the retrieval flowrate of the water from the polishing pond is between about 2 to times greater than the inflow into the polishing pond 22 and retrieval of water from

25 the polishing pond is performed intermittently such that the overall retrieval rate is balanced with the inflow rate. For example, for an inflow into the polishing pond of about 70 USGPM, the retrieval flow would be between about 140 USGPM to 560 USGPM for between about 30 minutes per hour and about 7 1/2 minutes per hour (e.g. 300 USGPM for 14 minutes per hour). This relatively larger retrieval flow can facilitate the ability to use the polishing pond to store untreated domestic effluent and catch up on subsequent quenching cycles and/or transfer water to other sources such as other lagoons or truck hauling.

26 Additional aspects of some implementations In some implementations, the fluid transportation assembly 48 may be configured and controlled so as to coordinate water retrieval from the domestic effluent treatment operation 12 with supply to the hydrocarbon coking operation 14. The retrieval pumps 26, the pre-treatment unit 28 and the interaction with the coker drum quenching cycle can be accomplished by operating the fluid transportation assembly 48 using timed pump cycles. The retrieval pumps 26 may be operated cyclically in on or off mode to retrieve the water from the polishing pond 22, operating for a pre-determined time to balance inflow of the primary effluent water 20 fed into the polishing pond 22 with the outflow of domestic effluent water from the polishing pond 22. For example, if the inflow into the polishing pond 22 is about 70 USGPM, the retrieval pumps 26 may be operated for 14 minutes every hour as a retrieval rate of 300 USGPM, thereby balancing the inflow and outflow on an hourly basis. Rather than using pond level for control, which may have lower accuracy as the change of level over a cycle is minimal and false signals may occur with wind and storm water ingress, the control may be based on inflow readings into the polishing pond 22.
In some implementations, the controller 64 may have a wireless network connection for monitoring and controlling various operating and measurement devices.
In some implementations, use of domestic effluent water as an on-site dirty water resource for coker quenching reduces demands for other sources of cleaner water, such as adjacent natural bodies of water.
In some implementations, if the volume of treated domestic effluent is sufficient to be accumulated as a source of coker cutting water, the treated domestic effluent may be alternately used for the cutting and removal of the coke that has accumulated within a coker drum. In other implementations, all treated domestic effluent water may be pooled together in a tank and then drawn on for either cutting or quenching operations according to operational needs.
Various modifications may be made to the disclosed implementations and still be within the scope of the following claims.

Claims

27

1. A process for integrating a domestic effluent treatment operation with a hydrocarbon coking operation, comprising:
retrieving from the domestic effluent treatment operation a domestic effluent water including pathogens;
pre-treating the domestic effluent water to reduce a concentration of pathogens therein, to produce a pre-treated water stream; and supplying the pre-treated water stream to a coker unit as coker quench water to quench the coker unit and produce a pathogen depleted spent quench water.

2. The process of claim 1, wherein the step of pre-treating comprises ultraviolet (UV) treatment of the domestic effluent water.

3. The process of claim 2, further comprising, prior to the step of pre-treating, the step of:
clarifying the domestic effluent water to increase the ultraviolet transmittance (UVT) thereof.

4. The process of claim 3, wherein the clarifying is performed so as to increase the UVT of the domestic effluent water above 40%.

5. The process of claim 3 or 4, wherein the clarifying is performed so as to reduce a concentration of algae in the domestic effluent water.

6. The process of claim 5, wherein clarifying comprises covering at least part of the domestic effluent treatment operation in order to reduce or prevent exposure to sunlight and thereby inhibit algae growth.

7. The process of any one of claims 2 to 6, further comprising:
measuring the UVT of the domestic effluent water prior to the step of pre-treating;
in response to a UVT measurement that exceeds a pre-determined threshold:
reducing energy input into the UV treatment.

8. The process of any one of claims 2 to 7, wherein the step of clarifying comprises filtering and/or chemical flocculation.

9. The process of claim 8, wherein the filtering comprises pressure-filtering and/or providing a plurality of filters arranged in series.

10. The process of any one of claims 1 to 9, wherein the step of pre-treating is performed proximate to the domestic effluent treatment operation.

11. The process of any one of claims 1 to 10, wherein the domestic effluent treatment operation comprises:
primary treatment of source domestic effluent in a lagoon, to produce a primary effluent water; and polishing treatment of the primary effluent water in a polishing pond, to produce the domestic effluent water.

12. The process of claim 11, wherein the step of retrieving the domestic effluent water further comprises:
providing a retrieval assembly for retrieving the domestic effluent water from the polishing pond.

13. The process of claim 11 or 12, wherein the step of retrieving the domestic effluent water further comprises:
periodically pumping the domestic effluent water out of the polishing pond at a periodic retrieval flowrate that is greater than an inflow rate of the primary effluent water into the polishing pond; and periodically stopping the pumping for a shut-off time period.

14. The process of claim 13, wherein the periodic retrieval flowrate and the shut-off time period are provided such that an overall retrieval outflow from the domestic effluent water is generally equal to inflow of primary effluent water into the polishing pond.

15. The process of claim 13 or 14, wherein the periodic retrieval flowrate is between 2 and 8 times greater than the inflow rate of the primary effluent water into the polishing pond.

16. The process of any one of claims 11 to 15, further comprising:
covering the polishing pond with a floating ball cover to inhibit growth of algae therein.

17. The process of any one of claims 11 to 16, further comprising:
controlling a level of the polishing pond around a pre-determined value.

18. The process of any one of claims 11 to 17, wherein the step of controlling the level of the polishing pond comprises:
measuring the level of the polishing pond;
in response to a level measurement being less than a first pre-determined threshold level:
recycling at least a portion of the domestic effluent water that is retrieved from the polishing pond back into the polishing pond; or stopping retrieval of the domestic effluent water from the polishing pond; or reducing the retrieval of the domestic effluent water from the polishing pond; and in response to the level measurement being greater than a second pre-determined threshold level:
increasing retrieval of the domestic effluent water from the polishing pond, by increasing retrieval rate and/or retrieval duration; or reducing recycled water back into the polishing pond, by storing and/or discharging to alternative containment facilities.

19. The process of any one of claims 1 to 12, wherein the step of retrieving the domestic effluent water further comprises:
periodically pumping the domestic effluent water out of the domestic effluent treatment operation at a periodic retrieval flowrate that is greater than an inflow rate into the domestic effluent treatment operation; and periodically stopping the pumping for a shut-off time period.

20. The process of claim 19, wherein the periodic retrieval flowrate and the shut-off time period are provided such that an overall retrieval outflow from the domestic effluent treatment operation is generally equal to inflow into the domestic effluent treatment operation.

21. The process of claim 19 or 20, wherein the periodic retrieval flowrate is between 2 and 8 times greater than the inflow rate into the domestic effluent treatment operation.

22. The process of any one of claims 1 to 18, wherein the step of retrieving the domestic effluent water further comprises:
continuously pumping the domestic effluent water out of the domestic effluent treatment operation at a generally constant retrieval flowrate, the generally constant retrieval flowrate being substantially similar to an inflow rate into the domestic effluent treatment operation.

23. The process of any one of claims 1 to 22, further comprising:
exposing all of the pre-treated water stream to temperatures of at least 70 C for at least 7 minutes in the coker unit, thereby destroying all pathogens present in the pre-treated water stream.

24. The process of any one of claims 1 to 23, further comprising:
recycling at least a portion of the pathogen depleted spent quench water as part of the coker quench water.

25. The process of any one of claims 1 to 24, wherein the hydrocarbon coking operation receives oil sands bitumen as a feedstock.

26. The process of any one of claims 1 to 25, further comprising:
diverting excess pre-treated water stream from the coker-unit upon detection that a flow rate of the pre-treated water stream entering the coker unit exceeds a capacity of the coker unit.

27. A system for integrating a domestic effluent treatment operation with a hydrocarbon coking operation, comprising:
a retrieval assembly for retrieving from the domestic effluent treatment operation a domestic effluent water including pathogens;
a pre-treatment unit in fluid communication with the retrieval assembly configured for receiving and pre-treating the domestic effluent water to reduce a concentration of pathogens therein, to produce a pre-treated water stream; and a supply assembly in fluid communication with the pre-treatment unit for receiving the pre-treated water stream and supplying the same to a coker unit as coker quench water to quench the coker unit.

28. The system of claim 27, wherein the pre-treatment unit comprises an ultraviolet (UV) treatment unit.

29. The system of claim 28, wherein the UV treatment unit comprises multiple UV reactors.

30. The system of claim 28 or 29, further comprising a clarifying device for clarifying the domestic effluent water to increase the ultraviolet transmittance (UVT) thereof prior to introduction into the UV treatment unit.

31. The system of claim 30, wherein the clarifying device is configured to sufficiently clarify the domestic effluent water so as to increase the UVT of the domestic effluent water above 40%.

32. The system of claim 30 or 31, wherein the clarifying device is configured to sufficiently clarify the domestic effluent water so as to reduce a concentration of algae in the domestic effluent water.

33. The system of any one of claims 30 to 32, wherein the clarifying device comprises a covering deployed over at least part of the domestic effluent treatment operation in order to reduce or prevent exposure to sunlight and thereby inhibit algae growth.

34. The system of claim 33, wherein the covering comprises a floating ball covering.

35. The system of any one of claims 28 to 34, further comprising:
a UVT measurement device for measuring the UVT of the domestic effluent water prior to the UV treatment unit;
wherein the UV treatment unit is configured such that, in response to a UVT measurement exceeding a pre-determined threshold, energy input is reduced.

36. The system of any one of claims 30 to 34, wherein the clarifying device comprises a filtering unit.

37. The system of claim 36, wherein the filtering unit comprises a pressure-filtering device and/or a multi-filter device having a plurality of filters arranged in series.

38. The system of any one of claims 30 to 34, 36 or 37, wherein the clarifying device comprises a chemical flocculation unit.

39. The system of any one of claims 27 to 38, wherein the pre-treatment unit is located proximate to the domestic effluent treatment operation.

40. The system of any one of claims 27 to 39, wherein the domestic effluent treatment operation comprises:
a primary treatment lagoon for treating source domestic effluent, to produce a primary effluent water; and a polishing pond for further treating the primary effluent water, to produce the domestic effluent water.

41. The system of claim 40, wherein the retrieval assembly comprises an inlet that is configured and located in fluid communication with the polishing pond.

42. The system of claim 41, wherein the retrieval assembly further comprises a retrieval controller for controlling flowrates therein.

43. The system of claim 42, wherein the retrieval controller is configured so as to control a pump for periodic pumping of the domestic effluent water out of the polishing pond at a periodic retrieval flowrate that is greater than an inflow rate of the primary effluent water into the polishing pond, and periodical stopping of the pumping for a shut-off time period.

44. The system of claim 43, wherein the retrieval controller is configured to control the pump to provide the periodic retrieval flowrate and the shut-off time period such that an overall retrieval outflow of the domestic effluent water is generally equal to inflow of primary effluent water into the polishing pond.

45. The system of claim 43 or 44, wherein the retrieval controller is configured to control the pump such that the periodic retrieval flowrate is between 2 and 8 times greater than the inflow rate of the primary effluent water into the polishing pond.

46. The system of any one of claims 40 to 45, further comprising a floating ball covering provided on a surface of the polishing pond to inhibit growth of algae therein.

47. The system of any one of claims 40 to 46, further comprising a level controller for controlling a level of the polishing pond around a pre-determined value.

48. The system of claim 47, further comprising a level measurement device provided in the polishing pond for measuring the level of the polishing pond, and wherein the level controller is configured to:
in response to a level measurement being less than a first pre-determined threshold level:

recycle at least a portion of the domestic effluent water that is retrieved from the polishing pond back into the polishing pond; or stop retrieval of the domestic effluent water from the polishing pond; or reduce the retrieval of the domestic effluent water from the polishing pond; and in response to the level measurement being greater than a second pre-determined threshold level:
increase retrieval of the domestic effluent water from the polishing pond, by increasing retrieval rate and/or retrieval duration; or reduce recycled water back into the polishing pond, by storing and/or discharging to alternative containment facilities.

49. The system of any one of claims 27 to 48, wherein the supply assembly and the hydrocarbon coking operation are configured and operated for exposing all of the pre-treated water stream to temperatures of at least 70°C for at least 7 minutes in the coker unit, thereby destroying all pathogens present in the pre-treated water stream.

50. The system of any one of claims 27 to 49, further comprising a quench water recycle line for recycling at least a portion of a pathogen depleted spent quench water obtained from the coker unit as part of the coker quench water.

51. The system of any one of claims 27 to 50, wherein the hydrocarbon coking operation is configured to receive oil sands bitumen as a feedstock.

52. The system of any one of claims 27 to 51, further comprising a bypass system for diverting excess pre-treated water stream from the coker-unit upon detection that a flow rate of the pre-treated water stream entering the coker unit exceeds a capacity of the coker unit,

53. A process for integrating a domestic effluent treatment operation with a hydrocarbon coking operation, comprising:
retrieving water from a pond in a domestic effluent treatment operation, the pond receiving an inflow of effluent for treatment, wherein the retrieving comprises cyclically pumping an outflow of the water from the pond, wherein each pumping cycle provides a flowrate that is greater than the inflow rate of the effluent into the pond; and providing at least a portion of the outflow of the water retrieved from the pond as coker quench water to a hydrocarbon coking operation and using the coker quench water in a quenching cycle.

54. A process for integrating a domestic effluent treatment operation with a hydrocarbon coking operation, comprising:
retrieving domestic effluent water from the domestic effluent treatment operation, the domestic effluent treatment operation including:
treating domestic effluent in a primary lagoon to produce a primary effluent water; and treating the primary effluent water in a polishing pond to produce the domestic effluent water;
wherein the retrieving comprises:
cyclically pumping an outflow of the domestic effluent water, wherein each pumping cycle provides:
a pumping stage providing a retrieval flowrate that is greater than an inflow rate of the primary effluent water into the polishing pond; and a downtime stage providing sufficient time so that each pumping cycle retrieves an outflow of the domestic effluent water that is generally equivalent with the inflow of the primary effluent water; and providing at least a portion of the domestic effluent water retrieved from the polishing pond as coker quench water to a hydrocarbon coking operation and using the coker quench water in a quenching cycle.