Flooded sewer system in refinery?
Dear All, I am chemical engineer and working in oil refinery we are facing problem regarding oily sewer system.Few years ago flooded oily sewer system was designed in condensate area in order to handle oily water.But in 2008 it becomes fully flooded and even underground pipes also due to which explosion occoured as oil was flooting in all underground lines and sewer oits were full.This happened due to some ignition source nearby.I have few question regarding this 1).Is it standard practice to use flooded sewer system if yes tell me that standard and any refinery name win which it exists. 2).What is solution to solve this issue? 3).any modification? to avoid such future hazards? 4)What is best refinery practice of oily sewer system? 5) would you sujust to remove this system? 6)How problem could be solved? I have tried to convey mproblem i know it is difficult to understand if u dont have visited but i am expecting help from your side. Also refer some standar codes which would become helpful to solve this issue. and some standard codes regarding oily sewer system in refinery. as oily sewer and accidently oily sewer are also mixing due to leakage in underground lines.
Proper feedback is very important in closed loop system.Feedback is a value of output parameter given to the controller for comparison process so that it can compare the output with the set velue or set parameter.For example:Lets take a process of temperature control of a simple tank having water in it. It is having heater for maintaining the temperature of water. Temperature measurement device is there for water temperature measurement. Now the desired temperature of water is 60 degree Celsius. So seting this value in controller as set velue. As the water is being heated temperature rises. Measuring device ie RTD measures temp. And gives singnal to controller as feedback. The controller compares this feedback with set value and control the heater settings. So the temperature is controlled.
Feedback occurs when outputs of a system are routed back as inputs as part of a chain of cause-and-effect that forms a circuit or loop. The system can then be said to feed back into itself.In an organisational framework, however, this translates to a review process where employees (anonymously or otherwise) receive individual feedback from those who work with them.When such a feedback system has multiple rater groups, provides for anonymity and is used as a developmental tool in an organisation it is called 360 degree feedback.The benefits to be reaped by implementing a 360 degree feedback system in terms of performance increased through transparent communications and greater self-awareness are too immense to ignore, despite its challenges.Primarily concerned with helping employees understand how they can develop and help the organisation grow, the 360 degree feedback process’ essential use lies in enhancing the bottom line of an enterprise while creating an environment that fosters greater cooperation, collaboration, and success.I’ve read, researched, and written on this extensively on the Grosum blog, check it out for a deeper, more comprehensive look and answers to any other questions you might have!Footnotes 360 Degree Feedback - A Complete Comprehensive Overview
Imagine you have a process: anything you fancy... for example, a tennis-ball-throwing-machine, throwing a ball every 10 seconds to a tennis player.To read feedback, it could for example, detect if the player was able to return the ball. Then each time the system throws a ball, it checks if the player was able to return it.Now, add a "control" procedure to the machine: if the player is able to return the ball, throw the balls 1 second faster; if the player misses the ball, throw the balls 1 second slower.How does this work in practice? the machine starts throwing balls every 10 seconds. The player misses, so the machine throws every 8 seconds. Now the player is returning every ball, so the machine switches to 9 seconds. The machine is constantly analyzing feedback and changing it's behavior to match its user. The player might get distracted, tired, or inspired, thus his performance will vary in a "random" way, but the machine will keep adapting to the player.That's the feedback loop: the "response" of the system depends on the "feedback" obtained: throw a result, analyze feedback, adjust, throw a result, analyze feedback, adjust, throw a result, analyze feedback, adjust, forever.
Biological feedback loop?
Positive feedback, sometimes referred to as "cumulative causation", is a feedback loop system in which the system responds to perturbation in the same direction as the perturbation. In contrast, a system that responds to the perturbation in the opposite direction is called a negative feedback system. This is Feedback that results in amplification or growth of the output signal. The effect of a positive feedback loop is not necessarily "positive" in the sense of being desirable. Positive refers to the direction of change rather than the desirability of the outcome. The negative feedback loop tends to reduce or inhibit a process, while the positive feedback loop tends to expand or promote it. Hope I helped =) --Macy ♥
How does a feedback loop work?
There are two basic types of feedback loops, the negative and the positive. Biological systems maintain stability using negative feedback. Let me use an example, the control of the acidity of the blood. It must be tightly controlled at a pH of 7.4, just slightly alkaline from water. If the pH goes down, meaning that the blood is getting more acidic say from the metabolites created when using the muscles, the pH in the cerebrospinal fluid also goes down. This is sensed by a portion of the brainstem which detects the difference between what the pH is and what is should be. This brain area then sends a control signal to the portion of the brain that controls the breathing rate, telling it to increase. That increase causes more carbon dioxide to be exhaled, which raises the pH of the blood back to its normal state. When it is back to its normal level, the breathing rate goes back to its normal rate. In summary, negative feedback brings the system back to a set value. This is analogous to a thermostat which turns on the heat when the house gets cold, but it shuts off the heat when the temperature gets back to the setpoint on the thermostat. The other type of feedback is positive feedback. With positive feedback, any error is magnified. If the positive feedback has a small gain, the system will reach a new stable state which is different from the original. If the positive feedback has a larger gain, the system becomes unstable. A biological example of positive feedback is the spread of contagious disease. The epidemic starts with a small number of cases, but each of those can spread it to new victims, and they will, in turn, spread it to even more victims. That is, the positive feedback here has an exponential growth.
DevOps is a way of working that emphasizes the need for learning and improving everything related to value delivery. You measure and adjust. You are focusing on small deliverables so that you get more rapid feedback and adjust faster at lower cost. As you mature with more automation and decreasing time to production, your feedback loops are amplified and you learn faster.The above isn't theory. I execute against that model daily.
Precisley what Naveen S Kumar says. In an open loop control system you are never measuring what the current state of your output is. You don't have any information to send to your controller from the current state of your system. Open loop control systems are like a normal washing machine. While your clothes are being cleaned you do not measure their "cleanliness". You do not feed this information back to the control unit of the machine. It runs the programmed sequence, sloshes your clothes about in soap suds for a while and then spins fast to remove the water afterwards. Nothing special here. No feedback of information here.The second special washing machine some how allows you to measure the cleanliness of the clothes. If they are clean enough the machine can be stopped. You have feed-back of information here, which allows you to use your resources economically. This is something open-loop systems do not have. If you add feedback to an open loop system you close the loop. Adding feedback changes the nature of the open-loop system. You can no longer call it by that name.Image of washing machine taken from http://www.gograph.com/vector-cl....
What is a Closed Septic System?
a closed septic system is a waste unit that has been emptied and is determined to be not usable. or there has been a upgrade say sewer line has been installed. which the old system should of been collapsed and cleared out. hope this helps
A closed loop system is one where the output is fed back into the the system as an input in some way.The term “Cybernetics” comes from the Greek word “kybernetes” which means steersman on a boat. The passengers in the boat want to get to where they are going in a nice straight line. So when the steersman sees that the boat is drifting left, he will steer it right. And when he sees that it is drifting right, he will steer it left. This is closed loop control.Another example is a thermostat. You set the desired temperature. The system compares the current temperature to the desired temperature. If the room is hotter than the desired temp, turn off the heating, but if it is colder, turn it on.This is the most basic idea of a closed loop system. Sense the output of the system and feed that information back in as a control signal. Now, if the steersman becomes blind or the thermostat temperature sensor breaks, then the system will not work as desired. The loop will be broken.