New Mars Forums

tahanson43206

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Registered: 2018-04-27

Posts: 19,392

Entropy Maintenance Replacement Life Cycle

This new topic is offered to assist with collection of insights, tips, best practices and general knowledge to guide planners who are thinking about or actually building hardware intended for service on Mars.

In numerous topics elsewhere in the NewMars forum, members have posted about maintenance issues they have encountered on Earth.

The hope is that experiences of citizens of an advanced technical society on Earth will be useful in guiding those who are thinking about how to design equipment to sustain life on Mars (or anywhere away from Earth) ** and ** to permit problem diagnosis and modular repair.

(th)

tahanson43206

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Registered: 2018-04-27

Posts: 19,392

Re: Entropy Maintenance Replacement Life Cycle

To lead off this new topic, I'd like to comment upon dishwashers ...

Dishwashers have a variable lifetime, depending upon the quality of design and manufacture, and on the combination of inputs and operation loads.

A brand new dishwasher installed in 2015 has just failed in 2020.  I suspect the early failure is due in large part to a poor choice of dish washing powder.  It was less expensive than name brands, but it delivered calcium deposits.  I suspect that if I were to disassemble the equipment between the motor and the rotating components of the dishwasher, I'd find buildup of calcium deposits.

The city water may be a factor as well, but I have no way to evaluate the load of dissolved minerals that arrive as an input to the dishwasher from the hot water heater.

I expect that dish washing equipment will be desired by citizens living on Mars, as well as passengers and crew on RobertDyck's Large Ship.

A way of monitoring the quality of liquids fed into any machines designed for this purpose would seem appropriate.

The needs of humans for potable water (mineral content is desirable for health) are not necessarily the same as the needs of a dishwasher.

(th)

SpaceNut

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From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Entropy Maintenance Replacement Life Cycle

The portable water system also relies on the recycling equipment as well for breaking down as we collect and reuse this commodity.

Another system with connection to water will be the electrolysis unit as its part of the refueling of rockets insitu once on mars that can break down just as easily to water mineral content.

Final system that uses water will be the washing machines which will get a heavy use by all to keep clean clothes.

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,392

Re: Entropy Maintenance Replacement Life Cycle

For SpaceNut re #3

Thank you for giving this new topic a boost!  I hope that NewMars members will add posts about specific design considerations to insure that every item of equipment shipped to or designed for manufacture on Mars is maintainable there, by Jack-of-all-Trades folks.

<Item> I'm not sure what you have in mind as "portable water system" so hope you will elaborate
<Item> There is an opportunity to post about maintenance issues for electrolysis equipment
<Item> Washing machines (as distinct from "dish" washing machines ... I'm assuming you are thinking of linen/cloth items to be washed?

<Item> Recycling equipment is a term that covers a ** lot ** of territory ... any chance you can add some detail ?

(th)

GW Johnson

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From: McGregor, Texas USA

Registered: 2011-12-04

Posts: 5,800

Website

Re: Entropy Maintenance Replacement Life Cycle

I think Spacenut meant "potable water".

GW

---

GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Entropy Maintenance Replacement Life Cycle

I actually had 2 thoughts going in my little pea brain which only came out half way... in that a portable potable system for a long range rover for human use would be completely different than that of a fixed habitat base solution.

Filters need replacing in any recycling system not to mention soap seperation for reuse if its coming from wash water usage.

The Sabatier reactor creates water as a function of co2 H2 mixing in the heated chamber. The water is pure and would need mineralization added to make it palatable.

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,392

Re: Entropy Maintenance Replacement Life Cycle

For GW Johnson and SpaceNut ...

Portable Potable Water equipment makes sense .... What I'm hoping this topic will lead to is a set of posts which will provide guidance for someone designing one of those ... The need exists on Earth as well as Mars ....

For SpaceNut ... static filters are the current default method of removing unwanted molecules from a stream of water ... Each such filter needs a dynamic cleaning procedure.  The filter much be designed for many cycles of use/cleaning/reuse.   

What I'm looking for is the Holy Grail of all water purification systems .... dynamic molecule sorting ... A sense of what is possible can be gleaned from the centrifugal separation of molecules by atomic weight .... this process is used for a variety of separation processes.

However, what I'm looking for is a system that processes individual molecules and sorts them so they are collected by type at an output port.   Something like that may exist right now, but I'm not aware of it.

The advantage of such a system is that the need for a static filter is reduced, although it may not be eliminated.  What ** may ** be possible is a hybrid system, consisting of a static filter and a dynamic cleaning operation that keeps the filter unclogged.

(th)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,431

Re: Entropy Maintenance Replacement Life Cycle

Found a topic Enclosed Life Support Systems (ECLSS) with the use of nature....