A dual energy gas water heater is described and wherein a square flange, curved resistor style resistive heating element, is secured in a bottom portion of the tank of the water heater spaced above a top wall of the combustion chamber. A gas burner is secured in the combustion chamber and connected to a gas supply line through a gas valve. The curved resistive heating element is a low density, long life, element having a density in the range of about 20 to 80 watts/sq. inches. A switch is secured between the thermostat of the resistive heating element and the voltage supply line. A controller selectively operates the switch and the gas valve to disconnect the voltage supply line from the thermostat and/or shut-off the gas valve secured to the gas supply line depending on the desired source of energy. The controller is adapted to be optionally controlled by a utility/provider through a communication link. Renewable energy source may also be secured to an additional resistive heating element to improve the efficiency thereof.

The purpose of the present invention is: to enable hot water at a required temperature to be supplied, even in cases when compressor load factor is low; to suppress heat dissipation from a waste-heat recovery device; and to improve waste-heat recovery rate. A waste-heat recovery system in an oil-cooled gas compressor is provided with: a compressor main body (3); an oil separator (6); gas piping (8) which supplies, to a demanded destination compressed gas separated from oil by the oil separator; oil piping (7) which returns, to the compressor main body, the oil separated by the oil separator; and a waste-heat-recovery heat exchanger (10) which recovers heat from the compressed gas and/or the oil. The waste-heat recovery system is also provided with: a hot-water storage tank (19); circulation circuits (17, 18) in which a heat medium is made to circulate between the waste-heat recovery heat exchanger and the hot-water storage tank; a circulation pump (22) provided to these circulation circuits; and a control device (32) which, in cases when the temperature of the oil or the compressed gas subjected to heat exchange in the waste-heat-recovery heat exchanger is equal to or less than the temperature of the hot water in the hot-water storage tank, stops the circulation pump or reduces the rotational frequency of the circulation pump.

A method of connecting a heat exchanger, which is used primarily in oil and gas operations to heat tanks of liquids, such as drilling mud, water, heavy oil or other such fluids from freezing or becoming too viscous to pump, to a tank.

An ultra-low liquor ratio fabric dyeing machine includes an assisting heat exchanger and a direct temperature rise/lowering device. The assisting heat exchanger or multiple ones of the assisting heat exchanger are additionally included in the dyeing machine. The assisting heat exchanger includes an external pipe that is mounted to a pump pipe of a pump at an inlet port, an outlet port, or both inlet and outlet ports thereof and is mounted with inlet and outlet openings for steam and cooling water in order to serve as an external casing that houses the pump pipe, while the pump pipe serves as a heat exchange pipe of the heat exchanger. The direct temperature rise/lowering device is mounted to a dyeing bath of the dyeing machine to directly introduce steam or cold water therein for quickly increasing or decreasing the temperature of the dyeing bath.

A combined heat, cooling and power system is configured to generate energy as well capture a large percentage of energy that would otherwise be lost using components, including heat transfer components, embedded within a vessel to transfer energy in the form of heat to liquid within the vessel.

A heat exchanger which is used primarily in oil and gas operations to heat tanks of liquids, such as drilling mud, water, heavy oil or other such fluids from freezing or becoming too viscous to pump.

Provided is a refrigeration cycle apparatus configured to perform a heating operation and a simultaneous heating and hot-water supply operation. The refrigeration cycle apparatus is configured to execute an operation mode circulating refrigerant through, in order, a discharge outlet of a compressor, a first heat exchanger, an expansion device, a second heat exchanger provided to a water tank, and a suction inlet of the compressor, and causing the refrigerant flowing through the second heat exchanger to evaporate by heat generated by a heat source provided to the water tank.

A heat exchanger, comprising at least a double shell, wherein the lower portion of the inner space of the inner shell is filled with liquid phase change medium, and at least one coiler is provided in the upper portion. The heated fluid flows in the coiler. After the downstream side pipe of the coiler is pierced through the inner shell, at least one surrounding pipe is formed in the cavity between the double shells. The bottom heat exchange plate of heat exchanger of the inner shell is located above the heat source. The cavity between the two shells forms the flue gas passage. After bottom heat exchange plate of the inner shell is heated by the heat source, the flue gas rises from the bottom of perimeter of the inner shell along the flue gas passage and the heat is transferred to the heated fluid in the surrounding pipe. The heat device using the heat exchanger according to the present invention can significantly improve the efficiency of heat utilization.

The purpose of the present invention is: to enable hot water at a required temperature to be supplied, even in cases when compressor load factor is low; to suppress heat dissipation from a waste-heat recovery device; and to improve waste-heat recovery rate. A waste-heat recovery system in an oil-cooled gas compressor is provided with: a compressor main body (3); an oil separator (6); gas piping (8) which supplies, to a demanded destination compressed gas separated from oil by the oil separator; oil piping (7) which returns, to the compressor main body, the oil separated by the oil separator; and a waste-heat-recovery heat exchanger (10) which recovers heat from the compressed gas and/or the oil. The waste-heat recovery system is also provided with: a hot-water storage tank (19); circulation circuits (17, 18) in which a heat medium is made to circulate between the waste-heat recovery heat exchanger and the hot-water storage tank; a circulation pump (22) provided to these circulation circuits; and a control device (32) which, in cases when the temperature of the oil or the compressed gas subjected to heat exchange in the waste-heat-recovery heat exchanger is equal to or less than the temperature of the hot water in the hot-water storage tank, stops the circulation pump or reduces the rotational frequency of the circulation pump.

An apparatus for managing hot water in a hot water storage tank heating system has one or more temperature sensors, a mounting bracket, a computer implemented processing arrangement configured to receive the temperature sensor signals and an interface to communicate with a user or additional processors either locally or remotely.