A compound multi effect distillation (MED) system of integrated backward and forward fed MED systems. Heated concentrate from the hottest effect of the backward fed MED system is delivered as feed to the hottest effect in the forward fed MED system, to generate a more concentrated brine than possible using any of the systems alone. Furthermore, coupling the systems creates additional operational advantages and increases distillation efficiency.

Certain aspects of a natural gas liquid fractionation plant waste heat conversion to power using Organic Rankine Cycle can be implemented as a system. The system includes a heating fluid circuit thermally coupled to multiple heat sources of a natural gas liquid (NGL) fractionation plant. The system includes a power generation system that includes an organic Rankine cycle (ORC), which includes (i) a working fluid that is thermally coupled to the heating fluid circuit to heat the working fluid, and (ii) an expander configured to generate electrical power from the heated working fluid. The system includes a control system configured to actuate a set of control valves to selectively thermally couple the heating fluid circuit to at least a portion of the multiple heat sources of the NGL fractionation plant.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power, cooling and potable water using integrated mono-refrigerant triple cycle and modified MED system can be implemented as a system that includes two heating fluid circuits thermally coupled to multiple heat sources of a NGL fractionation plant. An integrated triple cycle system, which includes an organic Rankine cycle (ORC), a refrigeration cycle and an ejector refrigeration cycle, is thermally coupled to the first heating fluid circuit. A MED system, configured to produce potable water, thermally coupled to the second heating fluid circuit. The system includes a control system configured to actuate control valves to selectively thermally couple the heating fluid circuits to portions of the heat sources of the NGL fractionation plant.

Marine engine exhaust includes pollutants such as CO.sub.2, NO.sub.x and SO.sub.x. An on-board system and method for the simultaneous removal of these pollutants includes obtaining seawater from the water on which the marine vessel travels, purifying the seawater to remove a portion of hard ions, concentrating the seawater to yield a concentrated brine solution, treating the concentrated brine solution with a chemical softener to yield a treated brine solution, acidifying the treated brine solution, and utilizing the acidified brine solution in a chlor-alkali process to yield sodium hydroxide. The sodium hydroxide can be used in an acid gas scrubber to remove CO.sub.2, NO.sub.x, and SO.sub.x from the marine engine exhaust gas.

Embodiments of the invention provide a method for producing a treated water stream. The method includes receiving a feed stream including at least one substance dissolved in a water phase, and processing the feed water stream in a plurality of stages arranged in operation from a lowest temperature and pressure to a highest temperature and pressure, to produce the treated water stream and a concentrated stream. Each stage includes a vessel, a heat exchanger, an evaporator, and a condenser. Each evaporator is configured to evaporate an amount of water using one of direct heat or indirect heat. Each condenser is configured to condense at least a portion of steam generated by a successive stage. In accordance with various embodiments, the plurality of stages is arranged in series. In other embodiments, the plurality of stages is arranged in parallel.

A thermal desalination system, comprising a multi-effect evaporator comprising a plurality of effects, configured to produce product water and brine and a fluidized bed crystallizer, configured to remove dissolved minerals and/or solids from the water, wherein the fluidized bed crystallizer is disposed between at least two effects of the multi-effect evaporator.

Disclosed is a purified dialkyl furan dicarboxylate (DAFD) vapor composition containing at least 99.5 wt. % DAFD; 5-(alkoxycarbonyl) furan-2-carboxylic acid (ACFC) that, if present, is present in an amount of not more than 1000 ppm, alkyl-5-formylfuran-2-carboxylate (AFFC) that, if present, is present in an amount of not more than 1000 ppm, 5-(dialkoxymethyl)furan-2-carboxylic acid (DAFCA) that if present, is present in an amount of not more than 1000 ppm, and alkyl 5-(dialkoxymethyl)furan-2-carboxylate (ADAFC) that if present, is present in an amount of not more than 1000 ppm, in each case based on the weight of the DAFD vapor composition.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and potable water using organic Rankine cycle and modified multi-effect distillation systems can be implemented as a system that includes two heating fluid circuits thermally coupled to two sets of heat sources of a NGL fractionation plant. The system includes a power generation system that comprises an organic Rankine cycle (ORC), which includes (i) a working fluid that is thermally coupled to the first heating fluid circuit to heat the working fluid, and (ii) a first expander configured to generate electrical power from the heated working fluid. The system includes a MED system thermally coupled to the second heating fluid circuit and configured to produce potable water using at least a portion of heat from the second heating fluid circuit. A control system actuates control valves to selectively thermally couple the heating fluid circuit to a portion of the heat sources of the NGL fractionation plant.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and cooling capacities using modified Goswami system can be implemented as a system. The system includes a waste heat recovery heat exchanger configured to heat a buffer fluid stream by exchange with a heat source in a natural gas liquid fractionation plant. The system includes a modified Goswami cycle energy conversion system including one or more first energy conversion system heat exchangers configured to heat a working fluid by exchange with the heated buffer fluid stream, a separator configured to receive the heated working fluid and to output a vapor stream of the working fluid and the liquid stream of the working fluid, a turbine and a generator, wherein the turbine and generator are configured to generate power by expansion of a first portion of the vapor stream of the working fluid, and a cooling subsystem including a cooling element configured to cool a process fluid stream from the natural gas liquid fractionation plant by exchange with a condensed second portion of the vapor stream of the working fluid.

The present disclosure relates to a multi-effect desalination apparatus by partially dosing acids into only evaporators corresponding to a relatively high temperature part, while dosing a polymer-based anti-scalant into all the evaporators, to minimize a risk of a scale and corrosion with maximizing a top brine temperature of desalination facility, and a desalination method using the same.