A full system for a resort

Tranquility · Post by **Tranquility** » Fri May 19, 2006 7:05 pm

I own an island in Belize and over the next few years we'll be building an exclusive boutique resort to cater to a higher end clientele. The resort will have our home, buildings to house a staff of 20-25, 10-12 individual guest canbanas, and a bar and restaurant area. The idea is to have the Guest Cabanas spead out so they are no closer than 80 feet apart to give total privacy. The island is totally covered in vegetation, mostly mangrove.
I have pretty much NO knowledge of septic systems other than the basics and what was installed while building our home in California. I've read many of the posts and other articles around the web and have a basic idea of what I'd like to accomplish. However, I don't even know if it's possible so here I am.
All buildings will be constructed about 6 feet above ground and could be a shade higher if necessary. I would expect the staff housing area to get the most heavy and consistent use but not sure yet how the cabanas will get used. I'll think positive and hope for thirty percent occupancy in the first year with a steady climb from there. Half the cabanas will hold 2 people and half 4 people. There are leaves dropping everywhere constantly and an abundant supply of seagrass that washes ashore daily. We haven't begun to gather this stuff yet so i don't have a weight but I think it's safe to say we'll have enough for anything we want to do for composting. Very few coconut husks until the young ones start producing.
If I could get everything I wanted, I would like to have a system for every 2 cabanas, one large one for the staff, one for our home, and one for the restaurant. I'd like to have the system operate with regular 1.6 gal. toilets and separate the excess water. From there, collect the methane and perferrably bottle it so they can be moved around from say the staff housing where a lot might be produced, to individual cabanas that might struggle to produce much. I would then like to use the gas to operate on demand water heaters for each cabana or use it for cooking or gas refridgerators. I'd like to get the grey water treated well above minimum standards and water the landscape with it. Finally, I 'd like to accomplish this with no smell whatsoever. Is this even possible?

Average temperatures in Belize are well over 80 degrees.

I know the 1.6 toilets would be a problem but I have a few reasons to try to keep them. Most importantly, this will be a $500 a night resort and I worry that anything other than what looks and feels luxurious would be a real turn off and hamper our ability to service the clientele we want to attract. So I don't think composting or ultra low flow will fit that need. Also, I was hoping to have the system centrally located in between two cabanas located at least forty feet away from the actual system. So the fall may be too gradual without the help of the extra water.

I could have the ultra low flow toilets in the staff housing but that's about it.

Is there a complete system that could be designed to accomodate all my needs? Should I give up on the idea of creating enough gas to use it for the water heaters? Any help would be terrific. Please keep in mind I'm no biologist and could be a little slow on the uptake.

Thanks

Post by **Bob** » Thu May 25, 2006 9:32 am

Sounds like a very interesting project!

And the short answer to your question about whether a complete system could be designed to accomodate your needs is yes. But whether it is economically feasible is another question. The devil is in the details.

A quick calculation shows that you should be able to generate 300-350 cu ft of biogas per day. This is based on the assumption of 50 people plus 50 lbs/day of leaves and kitchen scraps. (I don't know about the sea grass. I'm guessing the salt content could be a problem.)

Whether or not this makes sense depends on a number of things. What is the local cost of propane? Do you have other reasons besides economic ones for doing it? (e.g. will you be promoting your resort as as an "eco-resort"?) What are your other alternatives (for both fuel and waste treatment) and how would the cost of this system compare with them? What is the local cost of labor to operate and maintain the system? etc. etc.

I have been involved with design of systems for a couple of similar projects here in Alaska. In this one, (also with a central lodge and multiple, separated cabins) for example, it was not feasible to connect all the remote cabins to the central system (because of the distance and cost of running pipe between them ), nor would it have made sense to build, operate and have to maintain multiple separate digesters for each cabin. What we ended up with was a central system for the main lodge only, and stand-alone composting toilets in each of the cabins. But then their budget, regulatory constraints, soil conditions, and local labor costs, etc. may all have been completely different from yours.

Tranquility · Post by **Tranquility** » Mon Jun 12, 2006 10:07 pm

Sorry for the delay, I've been in Belize with very limited computer access.

The budget is always a concern but I want to do things right. It needs to meet certain governmental effluent regulations but I was hoping to also be somewhat creative with the system to add to the eco-friendly aspect of the resort. Labor is cheap and I'll have plenty of people around to take care of maintaining the system.

What can be done to separate the water from the solids before it enters the digester? Are there any commercial systems you would recommend I read up on that might help me achieve my goal? Do the systems you design have effluent specs that can be presented to the powers that be within the Belize environmental departments?

Doug

http://www.tranquilitycaye.com

Post by **Bob** » Tue Jun 13, 2006 1:23 pm

What can be done to separate the water from the solids before it enters the digester?

That may or may not be an issue, depending on the type of digester design -- whether a so-called 'dry' design or a 'wet' design. Ideal would be to design a collection system and digester that match. In other words, if you use water flush toilets and a water-borne piping system, go with a 'wet' design. If you can come up with a different way to collect the wastes and get them into the digester without adding enough liquid required to make them pumpable, you could go with a 'dry' design.

Are there any commercial systems you would recommend I read up on that might help me achieve my goal?

The only commercial anaerobic digester systems I am aware of are sized for dairy farms or municipal wastewater treatments -- many thousands or millions of gallons/day.

Do the systems you design have effluent specs that can be presented to the powers that be within the Belize environmental departments?

Most such systems -- at least in this country -- require ongoing testing to insure continued compliance. That should be probably factored into your budget for operating costs. But yes, we could design a system capable of producing effluent of whatever quality the regs specify.