Abstract: Hydraulic piston pump assemblies are disclosed herein. The hydraulic piston pump assemblies may include a hydraulic unit base that includes a plurality of pump pistons to output hydraulic fluids with different characteristics that can be selectively used based on load conditions.

Abstract: Hydraulic fluid release valve assemblies are described herein. The hydraulic fluid release valve assemblies may include a hydraulic unit base with a hydraulic fluid return channel and a hydraulic fluid release valve that is at least partially inserted in the hydraulic fluid return channel. The hydraulic fluid release valve assembly may further include a driving assembly to contact with the hydraulic fluid release valve to apply a pushing force on the hydraulic release valve to open the hydraulic fluid release valve, and an electrically powered driver connected to the driving assembly, the electrically powered driver, when actuated, causes the driving assembly to move to apply the pushing force to the hydraulic fluid release valve.

Abstract: A process for removing organic compounds, including nitro-hydroxy-aromatic compounds and amines, from alkaline wastewater, and in particular from wastewater generated in the production of nitrobenzene, dinitrobenzene, nitrotoluene and dinitrotoluene. The process involves distilling the alkaline wastewater steam at or near atmospheric pressure until it is concentrated five to twenty-five fold. The distillate includes water, which may be discharged to the environment, subjected to biological treatment, or recycled for use in the production process; and volatile organics, which are phase separated from the aqueous portion of the distillate and which may be recycled to the crude product stream. The concentrated residue from the distillation may be incinerated or subjected to biological treatment.