How to drain condensate from a domestic gas cylinder: step by step instructions

Does every refueling of your gas cylinder last for a shorter period of time? Or maybe you noticed a deterioration in the quality of the flame - the burner puffs and goes out from time to time? The reason for this may be condensation that has accumulated in the cylinder after many refills. If you drain it and pump in high-quality gas at a specialized gas station, gas appliances from a cylinder will work no worse than from a central gas pipeline: stably, evenly and without soot.

In this article, we will figure out what gas condensate is, where it comes from in a cylinder, whether it is necessary to get rid of it, and, most importantly, how to drain condensate from a household gas cylinder on our own.

What is condensing in a gas cylinder?

You can often notice that the gas in the cylinder has run out, but something continues to splash at the bottom. Some people think it's a little longer liquefied gas, it just won't come out and light up for some reason, but it doesn't. In fact, after using all the gas in the cylinder, there remains condensate - a residue that does not turn into a gaseous state at room temperature, and therefore does not escape under pressure and does not provide combustion.

To understand why condensation forms in your gas cylinder, let's figure out what it consists of.

The liquid that remains at the bottom of the cylinder after all the gas has been consumed usually consists of several components.

These may include:

• Gasoline - non-volatile refined products, a cross between butane and gasoline.
• Odorant - gas flavoring.
• Non-flammable impurities - not uncommon when using insufficiently purified gas or filling from an almost empty tank.
• Water - the rarest, but also the most dangerous component in this case.
• Butane - if the cylinder was used in frost.

The amount of such impurities present in the propane-butane mixture and forming condensate directly depends on the quality of the cylinder filling, as well as on the season.

Propane at normal pressure turns into gas at a temperature of -30 degrees, and butane - at 1 degrees below zero.

However, there are other products of oil refining, the boiling point of which is much higher: +30 - +90 degrees and above. That is, when heated to a sufficient temperature, they will behave in the same way as propane and butane - only heating a gas cylinder is very dangerous. And at room temperature, and even at increased pressure inside the cylinder, they remain in a liquid state, forming condensate.

These fractions, which are non-volatile under normal conditions, are called gasoline, and the higher the quality of the gas at the filling station, the lower the percentage of their content.

In addition to gasoline, an odorant is always present in the propane-butane technical mixture, which is filled with household gas cylinders. This is a special substance, ethyl mercoptan, with an extremely strong pungent odor: it is added in order to notice the leak in time and to have time to prevent the accumulation of gas in the room. In addition to the odor of an odorant, it is possible to timely detect a gas leak and analyze the composition of the gas mixture using special equipment - gas analyzer.

Without the addition of an odorant, the gas mixture would have no odor - just like purified propane, pure butane, and natural gas do not. The odorant is also non-flammable, so it remains in the condensate. Its volume is negligible, because according to the norms, 6-9 ml of flavoring agent is added per 100 kg of liquefied gas. However, after using the balloon, it almost completely remains in the condensate, due to a decrease in the total mass of substances, its concentration increases.

Normally, there should be no water or non-combustible impurities in the gas. However, when refueling at untested stations, anything happens, so we named these components of condensate as well. Water in a gas cylinder is dangerous because it provokes corrosion of the inner surface of the metal. The inside of the cylinder is not painted, and therefore easily rusts, and it is impossible to control this process. Such rust is found only when it eats through the metal - and this is already too late and extremely dangerous.

Butane is added to household gas cylinders in a smaller amount than propane: in summer, their ratio is about 2: 3, and in winter - at least 2: 8. This is only on condition of refueling at a specialized station, and not with automobile gas. As we already mentioned, butane, unlike propane, does not turn into gas at negative temperatures, so a cylinder installed on the street may run out earlier than expected.

If you used canned gas in late autumn or winter, especially if it was filled in summer, try to bring the bottle indoors after the gas stops flowing. Most likely, after its contents have warmed up to room temperature, you will be able to use it for a while.

You don't need to do anything with condensate or frost outside the cylinder, this moisture can only harm the container on which the layer is damaged paints: with prolonged and regular exposure, the steel of the cylinder can begin to rust, and corrosion can lead to leakage, fire and even gas cylinder explosion.

However, this will take quite a long time, so the user's task is limited to maintaining a uniform and high-quality color.

Frequency of draining condensate from the cylinder

But when should the condensate drain? This question is very individual and depends on the quality of the filled gas and operating conditions.

Many users of gas cylinders did not encounter such a need at all, while others do it before every refueling. Both of these extremes are normal behavior under certain conditions, and to determine which is closer to you, let's look at these conditions in more detail.

Option # 1 - refueling at a specialized substation

If you fill a cylinder at a specialized substation, you may not encounter condensate at all, for several reasons at once. Firstly, they fill up the "right" gas, with a high content of propane, and not just cheap butane, as at car gas stations.

Secondly, their gas quality control is much stricter, so the degree of gas purification is higher, and there are practically no impurities.

Thirdly, at most of such substations, cylinders are taken for exchange, and they are inspected before refueling. and maintenance, discarding excessively worn ones, and after refueling - monitoring safety and tightness. In particular, the substation workers drain the condensate if it has accumulated in the cylinder.

Even if you insist on refueling your particular cylinder, it will not be performed without first making sure that the unit is in good working order and safety. The fact is that specialized substations work officially, observing norms and technical requirements refueling cylinders are responsible for the safety of each customer.

Option # 2 - refueling at a gas station

Cylinders filled at gas stations, but used for domestic purposes, are much more prone to condensation.

If the balloon, refueled at the gas station, put at home, all impurities and weakly volatile gases will settle at the bottom, and remain there in the form of condensate. Therefore, when refueling with automobile gas, the condensate must be drained at least every 3 - 4 refueling, and better - before each.

We can separately mention small tourist gas cartridges with a volume of up to 1 liter. They have another outlet, reminiscent of a can for refueling lighters, and it is difficult and unsafe to do something with it other than its intended use. However, many craftsmen fill the cans with their own hands.

Although, in principle, it is more convenient and simpler when such cartridges are filled only at specialized points with gas of the correct composition and a high degree of purification, therefore, condensate does not form in them. Yes, and they are relatively inexpensive, and do not last for decades, like their big brothers, therefore, when such a can starts to junk, they usually just buy a new one.

Condensate drain instructions

If we neglect the procedure for draining the condensate, less and less gas will be placed in the cylinder each time, and it will not last for so long. In addition, the bay is a normal amount gas mixture into the cylinderwhere condensation has already accumulated, you run the risk of filling it to the eyeballs without leaving the prescribed 15% void for the gas cushion. This is extremely dangerous and fraught with rupture of the cylinder or explosion at the slightest additional heating or shaking.

To prevent undesirable consequences, let's figure out together how to properly clean a household gas cylinder from condensate.

So, the first step is to use or release the remaining gas.

If the tile or other equipment already does not work well from this cylinder, puffs, you can simply release the gas on the street. To do this, remove reducer and gradually open the valve. In no case do this near a house, fire, wiring, sparks, in a confined space: a meadow or field is ideal, where there are no people and the wind will quickly disperse the gas.

Violation of this simple rule can lead to poisoning, fire or explosion - do not risk your health and those around you. Keep in mind that when a large amount of propane-butane changes from a liquid to a gaseous state, the remaining liquid cools down a lot, and the cylinder becomes cold.

When the characteristic hiss ceases to be heard when opening the tap, we can say that the gas has run out. That is, it remained only in a gaseous and not a liquid state, exactly the same volume as the cylinder, so the pressure is not higher than atmospheric pressure, and it does not come out. Most likely, even at this stage, something will splash in the cylinder - this is condensation.

To get rid of condensation, do this:

1. Choose a place remote from housing and fire hazards, preferably not a sown field and not the shore of a reservoir. Wasteland, wild meadow is ideal. Do not drain the condensate directly near the filling station where you are going to fill the bottle.
2. If the gearbox is still in place, remove it.
3. It is advisable to prepare a glass or metal jar that can be tightly closed together with the drained substance.
4. Open the tap and find the branch pipe under it, where the gearbox was attached.
5. Turn the cylinder upside down, with this branch pipe away from you, directing it into the prepared container. For convenience, you can put a hose on it.
6. If the liquid does not flow, or not all of it has drained, tilt and shake the balloon so that the last milliliters flow out.
7. Be sure to close the valve so that the cylinder does not fill with air and moisture.

It is desirable that nothing splashes in the balloon after this procedure. Sometimes you can find a recommendation to fry empty cylinders in the sun with open valves in order to remove both condensation residues and water that could get into the cylinder. But this procedure can be unsafe, especially if you forget to open the valve, and an extra few milliliters of condensate will not play a role, therefore it is better not to dry the cylinders unnecessarily.

With proper operation, there is nowhere for water to come from, so you will not have a need to figure out how to properly drain water from a household gas cylinder, and drying is not required.

Safety rules when handling the cylinder

Gas cylinders are extremely dangerous. Every year, tens and hundreds of household gas cylinders explode, destroying housing and killing people, and in most cases, this is due to violation rules for their operation.

Refueling gas legally, at a specialized substation, along with a full cylinder, you will receive a memo on its safe transportation, storage and use. Among other things, it is forbidden to install cylinders closer than half a meter from a gas stove or a meter from a stove, heater or battery.

Do not allow the cylinders to heat up - from any devices or in the sun - this is fraught with rupture. Also, you cannot store them in a tightly closed cabinet without ventilation at the bottom of the doors: in case of a leak, gas will fill the cabinet, and in combination with oxygen from the air, the mixture becomes extremely explosive. The slightest spark or electrical discharge is enough, and there will be an explosion.

We also recommend that you read the article:Why gas cylinders explode: the main causes of accidents.

You should not use a winter gas mixture with a high propane content in the summer: it will evaporate too much active, and the balloon can swell or even burst from excessive pressure - and this is with walls made of steel with a thickness of 3 mm.

It is also forbidden to use swollen, wrinkled or damaged cylinders: there is no guarantee that it is airtight and will withstand a gas pressure of up to 8 bar.

Conclusions and useful video on the topic

So that there are definitely no questions left, we suggest watching a video on how condensate is drained from an empty cylinder:

When using gas cylinders at home, do not forget about the need to maintain them, because this is a matter of your safety. It is up to you to drain the condensate and check the integrity yourself or entrust it to professionals, and we have told you how to do it efficiently and safely.

Do you use gas cylinders and still have condensation after using gas? Tell us how you get rid of it - the feedback form is located at the bottom.

If you still have questions or want to express your opinion on the advisability of draining condensate at home, please join the discussion of the topic.