摘要:
A system for optimizing the control of the water temperature within a cooling tower is disclosed. The temperature and the relative humidity of the air outside the cooling tower are measured and are selectively utilized as inputs to a plurality of modules containing function blocks in a logic arrangement. The function blocks produce an output signal indicative of the wet bulb temperature of the outside air which is compared to the cooling tower water temperature causing the speed of the cooling tower fans to be adjusted in response to the temperature difference therebetween.
摘要:
A system for the automatic and continuous determination of the efficiency of a fossil fuel-fired vapor generator for utilization by an automatic load control (88) to control the distribution of the system load among a plurality of generators, wherein various heat losses from various combustion sources are separately determined, the individual losses summed (80) and subtracted (86) from 100 percent to obtain a measure of the vapor generator efficiency.
摘要:
A load control for a system comprised of a plurality of energy converters wherein a System Control Signal proportional to system load is developed and utilized to simultaneously adjust the rate of energy conversion of each of the converters in parallel in accordance with changes in system load. The rate of energy conversion for each converter, while operating under stead-state conditions for a predetermined period of time, is readjusted until its actual incremental cost of production is equal to a desired incremental cost.
摘要:
A method and apparatus for controlling the delignification process by monitoring and minimizing variations in the Kappa Number and the digester residual chemical concentration. A parameter representative of the H factor for the delignification process and a measurement of the initial chemical concentration are utilized to produce signals representative of the actual Kappa Number and the residual acid concentration in the digester. The expected perturbations in Kappa Number and the residual chemical concentration are compared with target values for same to produce estimated errors due to mismatch which are compared with actual measured errors for these parameters to produce compensated control errors for same. The compensated control errors are utilized to modify the target values for the H factor and the initial chemical concentration by modifying the chemical charge and the time versus temperature operating parameters of the digestings to regulate pulp Kappa number and spent cooking liquor residual chemical concentrations of the process.
摘要:
A method and apparatus for controlling the delignification process by monitoring and minimizing variations in the Kappa Number and the digester residual chemical concentration. A parameter representative of the H factor for the delignification process and a measurement of the initial chemical concentration are utilized to produce signals representative of the actual Kappa Number and the residual acid concentration in the digester. The expected perturbations in Kappa Number and the residue chemical concentration are compared with target values for same to produce estimated errors due to mismatch which are compared with actual measured errors for these parameters to produce compensated control errors for same. The compensated control errors are utilized to modify the target values for the H factor and the initial chemical concentration by modifying the chemical charge and the time versus temperature operating parameters of the digestings to regulate pulp Kappa number and spent cooking liquor residual chemical concentrations of the process.
摘要:
A system for optimizing the performance of a plurality of energy conversion devices is disclosed. Measurements of fluid flow into and out of the energy conversion devices, the efficiencies of the conversion devices and the power produced by the conversion devices are used as inputs to function blocks in a logic arrangements. The function blocks cause a decrease in load demand to be applied to the energy conversion device having the lowest efficiency and an increase in load demand to be applied to the energy conversion device having the highest efficiency.
摘要:
A load control for a system comprised of a plurality of energy converters wherein the energy output of all converters is adjusted in parallel to maintain the total rate of energy output from the system equal to demand and wherein during steady-state conditions the rate of energy conversion for that converter having the lowest incremental cost is increased and simultaneously the rate of energy conversion for that converter having the highest incremental cost is decreased a like amount.
摘要:
A system for the measurement and control of the rate of BTU input to a gas burner wherein a signal is generated corresponding to the square root of the product of the burner inlet pressure multiplied by the in-situ density olf the gas, which, multiplied by a signal of constant value, corresponds to the mass flow of gas to the burner. This signal is then multiplied by a second signal of constant value to generate a signal corresponding to the rate of BTU input to the burner and which is compared with a set point signal to regulate the mass flow of gas to the burner as required to maintain the rate of BTU input to the burner at set point.
摘要:
A method and apparatus for controlling the delignification process by monitoring and minimizing variations in the Kappa Number and the digester residual chemical concentration. A parameter representative of the H factor for the delignification process and a measurement of the initial chemical concentration are utilized to produce signals representative of the actual Kappa Number and the residual acid concentration in the digester. The expected perturbations in Kappa Number and the residual chemical concentration are compared with target values for same to produce estimated errors due to mismatch which are compared with actual measured errors for these parameters to produce compensated control errors for same. The compensated control errors are utilized to modify the target values for the H factor and the initial chemical concentration by modifying the chemical charge and the time versus temperature operating parameters of the digestings to regulate pulp Kappa number and spent cooking liquor residual chemical concentrations of the process.
摘要:
A cooling tower monitor for determining the performance of a cooling tower includes temperature transmitters for determining the input water temperature, the output water temperature and the surrounding temperature of the tower. A flow transmitter measures the output flow of water and a speed transmitter determines the flow of air through the tower. A relative humidity transmitter is also utilized to measure the surrounding relative humidity. The transmitters are connected to function blocks to generate a value corresponding to the performance of the cooling tower as a function of the parameters measured. A first set of function blocks utilizes the surrounding temperature and relative humidity to calculate the wet bulb temperature of the air outside the tower. This measurement is utilized in conjunction with the input and output temperatures as well as the air flow value to calculate a nominal or available water flow rate for the tower. A standard condition tower unit and rating factor for the tower are utilized in this calculation. The available flow is then divided into the actual flow as determined by the water flow transmitter to obtain the performance value.