Analysis Glycol Losses On Gas Dehydration Unit PT X Field Z

The dehydration process gas is a process of separation of gas from the water content by mixing an absorbent for example glycol, in PT X field Z process of dehydration of gas using triethylene glycol to decrease Water content Minimum below 7 lb / mmscfd to be sold to consumers. The goal of the research is to determine the water content that is absorbed in the contactor, knowing the number of glycol loss and knowing the cause of glycol loss after experiencing the process of dehydration. Every dehydrated process using glycol is always there whose name is glycol losses either in reboiler or contactor, but the losses are classified normal or abnormal loss, losses can be either liters or percentage loss glycol lost. To determine how much glycol is missing during the dehydration process then we have to look for production data such as gas flow rate data, inlet water content and outlet water content contactor then moisture content data, and the last data from glycol like SG Glycol and purity glycol, later from the data is known calculation of circulation glycol and know the amount of glycol loss whether the normal loss or abnormal loss. The water content omitted is 32.49 lbs / h while the Glycol losses found in the above-normal state are 0.35% with the lowest amount of Glycol losses of 0.02 gal / MMSCF and the largest 0.091 gal / MMSCF and the cause of Glycol loss Include the number of the tray, time, surface area of absorption, flow speed, and the temperature that is in the reboiler or the regeneration of glycol.


Introduction
Natural gas is fuel fossil a gaseous consisting mainly of methane (CH4).And can be found in oil fields, natural gas fields, and coal mines.When a gas rich in methane is produced through the putrefaction of bacteria anaerobic from materials organic other than fossils, it is called biogas.The impurities in the produced gas must be removed so that the combustion produced by the gas is complete.Water can reduce the energy produced during complete combustion, and it can also damage equipment to be used.The water content of gas dehydrated must be following the contract agreed upon in the stated contract.
The absorbent used in the gas drying process must have high water solubility, is not corrosive, is not easy to form a foam (foaming), is easily regenerated, and is cheap.Absorbent along with dry gas, forming foaming or heating in the reboiler are called glycol losses.Glycol losses are the loss of some of the content glycol used during the process dehydration.Glycol losses can occur due to the uneven contracting process or due to too high a moisture content in the composition of the mixture glycol.Often the occurrence of glycol losses in the process dehydration gas makes the use of glycol not meet existing standards.Therefore, glycol losses must be maintained so that the process dehydration gas can run optimally and continue to work economically.In a gas processing process, a dehydration process is needed to remove water content in the feed, so that unwanted things do not occur in the process.The thing that needs to be considered from the chemicals involved in that the solvent (water-absorbing material) must have the ability such as high absorption of water, and low absorption of hydrocarbons, Difficult to evaporate at the absorption temperature, low viscosity for easy absorption.Pump, and has good contact between gas and phases liquid, regeneration, low corrosion potential, easy to operate and maintain.

Types of Glycol
From the various solvents available, it turns out that glycol meets these criteria.There are four types of glycol that have been used successfully for dry natural gas, namely ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (TREG).
▪ Triethylene glycol has characteristics that tend to be the same as other types of glycol.
There are many uses of Triethylene glycol that can be utilized in the industrial world, one of which is as a desiccant in natural gas dehydration because Triethylene glycol has properties Hygroscopic that can absorb water.▪ Tetraethylene glycol (TREG) can be regenerated at temperatures up to 430 F, so it will produce very high purity.However, the price is very expensive so it is rarely used.

Determine glycol losses and their percentage
Glycol losses can occur in some gas dehydration tools, however, glycol losses occur mostly in TGRS and glycol contractors, because these two devices are very prone to glycol losses.If in TGRS, glycol losses occur as a result of the temperature reboiler being too high, exceeding the boiling point of the TEG so that the TEG evaporates and follows the water that will be treated by IPAL (Wastewater Treatment Plant).Whereas in the glycol contactor the temperature of the lean glycol which is too hot exceeds 15 º above the temperature of the gas entering the glycol contactor.So that the lean glycol will bond with the wet gas and go to the produced gas so that the glycol will occur in losses.The number of glycol losses can be determined in the following way.(Francis S and Richard E, 1991."Oilfield Processing Of Petroleum Volume One: Natural Gas" Oklahoma, 160).The process of gas dehydration does not always go well.Several problems arise during the process.This problem occurs in the dehydration process unit.The problem includes: 1. Absorber The main problem that occurs in the absorber is the inefficient dehydration process that occurs foaming and solubility of hydrocarbons in the glycol.
▪ Dehydration is not efficient; if dehydration is not sufficient then the gas from dehydration is still contained water with high enough levels.Causes of this include the water content in lean the glycol is too large, the absorber is inadequate, ▪ The temperature of the inlet Gas is too high, the temperature lean glycol is too low and over circulation or under circulation glycol.▪ Foaming will cause be carried out glycol to by the gas flow out of the absorber.As a result, there is a loss of glycol (glycol loss) in the dehydration process.The solubility of hydrocarbons in glycol in the absorber.

Reboiler
Operational problems in the reboiler include salt contamination, degradation glycol, and problems associated with acid gases.

Kontrol
In industry, dew points are used to indicate the water content in a gas stream.If the decrease in the dew point of the dehydrated gas is too small, there may be several causes, namely, the circulation rate is glycol too low, the lean concentration is glycol low, the occurrence of foaming, and the gas velocity in the absorber is too high.

Method
Final research entitled "Analysis of glycol losses in the gas dehydration unit".Compiled using a research method to make it easier to complete the Final Project.The research methods used are as follows: 2.1 Preliminary This preparatory stage is the stage of collecting initial information that is done to identify, formulate, and determine the objectives of problem-solving by considering knowledge based on existing literature.As in the production engineering literature on campus and E-book obtained from supervisors in the field.

Data Collection
Collection and processing are carried out in making this final project with observation and interviews.This is done by visiting the production field and observing the dehydration process and its flow.Then collect all the information about the data from the field that becomes the object of study.The data obtained from the field are in the form of gas flow data, water content, the weight of glycol, and other supporting data.From the data obtained, it will then be adjusted and processed based on the object of study, namely analyzing the glycol loss that occurs in the PT X.

Conclusion Stage
Stages At this stage, which is carried out after all the stages have been carried out, a conclusion is drawn from what has been obtained during the final project.Several points drawn into conclusions are referred to through the initial purpose of why this Final.

Result And Discussion
Below is the make-up data glycol carried out in 2022 presented in the Table 3.1, and Table 3.2 for result of calcultion of glycol losses.The result of above calculation is summirezed on the Table 3.3, below:

Conclusion
After carrying out the Final With the title Analysis Project Glycol Losses on the Gas Dehydration Unit at PT X field Z it can be concluded as follows: The water content removed is 32,49 lbs/hr, Glycol losses in the above conditions are said to be abnormal because the amount of Glycol losses lowest is 0.020 gal / MMSCF and the largest is 0.091 gal/MMSCF with a percentage Glycol losses of 0.35%.The cause of glycol losses is such as the number of trays in which the number of trays is very influential during the absorption process, the minimum number of trays on the contactor is 4 trays, while the absorption process in the field uses 8 trays so that it can increase the efficiency of glycol absorption at the contactor.The temperature at the Still Column and Reboiler in the field is designed to be 340 °f -400 °f, so that with this temperature it can evaporate the water contained in the gas without evaporating the glycol.The flow rate is also very influential on the rebellion process where if there is a little wet gas, the glycol flow rate must also be adjusted so that there are no glycol losses or waste glycol, for the flow rate in the field is 2.209 SCF / gal.Whereas the time for the paging process in the field can be said to be quite long, around 8 hours -24 hours, this is because when the control panel at TGRS operates, there are problems such as hours caused by factors from old equipment that can cause a decrease in the quality of the equipment.Meanwhile, the location of the potential for glycol losses is in the TGRS (Triethylene Glycol Regeneration System).Problem-solving that can be done to deal with the problem of Glycol losses or other problems, namely by maintaining or replacing equipment, this is because the equipment used is quite old and old.
c. lb water content = Water Removed x gas rate x information: Water removed = Water removed lb/mmscf Gas rate = mmscf d. percentage glycol loss = x 100% information: Vactual = volume of circulation Vsirkulasi = number of glycol needed in 1 hour Figure 2.1 is shown the flow chart of the stage research.

Figure
Figure 2.1 Research Stage

Figure 3 . 1 =
Figure 3.1 Comparison of Glycol Losses Source: research result

Table 3
.1 of Data Make up Glycol Source: research data

Table 3 .
3 Volume glycol loss percentage Source: result research calculation