Abstract: A gas scrubbing apparatus including at least two modules, each module including at least one process vessel for a gas scrubbing process, each process vessel being selected from an absorber, a regenerator, a scrubber, a reboiler, a heat exchanger or a combination thereof. Each process vessel has top wall, a base wall, and at least three sidewalls formed from a cementitous material. Each process vessel has inlet and outlet ports for fluid entering and leaving the process vessel when in use, formed within at least one of the top wall, base wall, or sidewall of each process vessel. The sidewalls of each process vessel define a polygon shaped cross-section, and at least one side wall of a first process vessel in a first module can be connected or abutted to at least one side wall of a second process vessel in a second module.

Abstract: A bubble generator for generating gas bubbles for a flotation vessel, the bubble generator including at least one inlet through which a water stream can enter the bubble generator; at least one pair of electrodes capable of electrically decomposing water to create gas bubbles; and at least one outlet through which water entrained with gas bubbles can exit the bubble generator. In use, at least one of the outlets is in fluid communication with a flotation vessel containing waste water including contaminants, the gas bubbles being used to separate at least a portion of the contaminants from the waste water in the flotation vessel.

Abstract: A gas scrubbing apparatus including at least two modules, each module including at least one process vessel for a gas scrubbing process, each process vessel being selected from an absorber, a regenerator, a scrubber, a reboiler, a heat exchanger or a combination thereof. Each process vessel has top wall, a base wall, and at least three sidewalls formed from a cementitous material. Each process vessel has inlet and outlet ports for fluid entering and leaving the process vessel when in use, formed within at least one of the top wall, base wall, or sidewall of each process vessel. The sidewalls of each process vessel define a polygon shaped cross-section, and at least one side wall of a first process vessel in a first module can be connected or abutted to at least one side wall of a second process vessel in a second module.