An oil or gas recovery process (10) is disclosed where resulting produced water includes silica. The process entails removing silica from the produced water via a two-stage process. In the first stage, magnesium oxide is injected into a Magnesium Dissolution Reactor (18) and mixed with the produced water to dissolve magnesium. Effluent from the Magnesium Dissolution Reactor (18) is directed downstream to a warm lime softener (22) where one or more alkaline chemicals are added to the produced water to raise the pH to approximately 10.0 to 11.5. Here, silica is co-precipitated with magnesium hydroxide and/or adsorbed onto magnesium hydroxide precipitates.

Disclosed are methods for seawater softening for the desalination plants (thermal and membrane) by using the carbon mineralization (CM) technique. Disclosed are several process flow diagrams in which the carbon mineralization is integrated at the upstream and/or downstream of the thermal and membrane desalination processes. By using these methods, the released CO2 from industrial factories, seawater feed minerals solutes shall be removed to improve the performance of the desalination plants. Most importantly, valuable products such as Ca/Mg carbonates and BaSO4, which are being used in building rocks, concrete, cement, paints, plastic, etc., can be produced.

Produced water from a crude oil or natural gas production process is purified using a membrane purification system for petroleum production, agricultural, commercial and domestic uses. The produced water is pretreated to remove, at least, particulates and oil from the produced water. The minimally pretreated water is then purified in a membrane purification system that is operated at conditions such that contaminants are removed. In particular, the membrane purification system is operated with pH adjustments to allow boron and ammonia to be effectively removed. In some embodiments, greater than 95% of the boron content and greater than 95% of the ammonia content are removed. Some method embodiments include no separate ion exchange separation step capable of removing ammonia.

A water heater system includes a water heater rack system with a plurality of vertically stacked tankless water heaters and a water heater storage tank and provides the ability to install a water heater in environments where horizontally oriented heater rack systems would not fit. The tankless water heaters comprise a bifurcated vent arrangement with separate intake and exhaust vents. Accordingly, vent pipes of diameters of two (2) inches or less may be used in comparison to coaxial vent arrangements which may have diameters of three inches or more. The smaller vent pipe diameter allows a plurality of water heaters to be stacked, one above the other, such that the water heater rack system has a maximum height of 76 inches or less. This vertical orientation may allow tankless water heaters to be installed in an environment where a horizontally configured plurality of tankless water heaters would not fit.

An apparatus for evaporative concentration of water, containing hardness-causing substances, to be treated using hot lime softening, includes: a first evaporator configured to form first concentrated water from the water to be treated by evaporatively concentrating the water by first heat exchange with hot steam; a hot lime softener configured to precipitate and to separate hardness-causing substances contained in the first concentrated water from at least a portion of the first concentrated water from the first evaporator by reaction with lime and configured to remove the hardness-causing substances from the first concentrated water; and a second evaporator configured to form second concentrated water by further evaporatively concentrating at least a portion of the first concentrated water that passed through the hot lime softener by second heat exchange with hot steam.

Produced water from a crude oil or natural gas production process is purified using a membrane purification system for petroleum production, agricultural, commercial and domestic uses. The produced water is pretreated to remove, at least, particulates and oil from the produced water. The minimally pretreated water is then purified in a membrane purification system, that is operated at conditions such that membrane scaling is reduced or prevented. In particular, the membrane purification system is operated to maintain the turbidity of clarified water feed to the system or intermediate aqueous streams that are cascading through the membrane purification system. Ensuring that the turbidity of the reject streams generated in the membrane system are useful in achieving long membrane operating life.

Described herein is a coagulant blend for use in SAGD water treatment systems. Specifically, a blend of high charge density polyamine and low charge density poly(diallylmethyl ammonium chloride (poly-DADMAC) is used in the warm lime softening treatment process to coagulate and flocculate solids.

According to some embodiments, a system for desalination of a liquid comprises at least one primary treatment process, at least one secondary treatment process, wherein the at least one secondary treatment process comprises at least one reactor, and at least one tertiary treatment process, wherein the at least one primary treatment process is configured to adjust a pH of the liquid to target pH level and to add at least one chemical additive to the liquid, wherein the at least one reactor is configured to heat the liquid to a temperature of at least 350 F. and to supply a pressure to the liquid to maintain the liquid in a liquid state, and wherein the dissolved salt of the liquid is configured to react with at least a portion of the at least one chemical additive to form an insoluble product within the at least one reactor.

A degasser includes a vessel having a series of chambers. Liquid containing a gas is directed through the vessel and the chambers therein. A stripping gas is injected into the vessel and moves through the vessel in a counter-current direction relative to the flow of liquid. More particularly, the stripping gas moves from one chamber to another chamber in an upstream direction (relative to the flow of the liquid) and is mixed with the liquid in each chamber, causing gas in the liquid to be displaced. Displaced gas is vented from the vessel at a location near where the liquid enters the vessel.

Produced water from a crude oil or natural gas production process is purified using a membrane purification system for petroleum production, agricultural, commercial and domestic uses. The produced water is pretreated to remove, at least, particulates and oil from the produced water. The minimally pretreated water is then purified in a membrane purification system, that is operated at conditions such that membrane scaling is reduced or prevented. In particular, the membrane purification system is operated to maintain the turbidity of clarified water feed to the system or intermediate aqueous streams that are cascading through the membrane purification system. Ensuring that the turbidity of the reject streams generated in the membrane system are useful in achieving long membrane operating life.