Dairy basics - Manure | |
| Written by Nancy Puck | |
| Tuesday, 17 September 2013 10:08 | |
Very good agitation might be the most important step in utilizing liquid manure as a nutrient to grow a crop. If every gallon is homogeneous throughout the pump-out, we have a better opportunity to be successful year after year using manure as fertilizer.
Well-agitated manure is predictable. Its nutrient content can be spread consistently throughout the field at agronomic rates. A manure lagoon without an ability to be well agitated is only as valuable as the poorest gallon of wastewater it holds in terms of nutrient value. There is too big of a risk of under-application and missing crop production opportunity when the manure can’t be evenly applied in the field.
Because of this, over-application happens too often, and this not only limits the higher return a farm could make by utilizing a nutrient asset to a fuller potential, but it also puts the farm at risk of environmental consequences.
Turning a wastewater into a high-value fertilizer is simple – agitate until everything is even and in suspension, sample the nutrient and apply correctly.
Manure, naturally, has many nutrients, micronutrients, biologicals and organic materials that are excellent at building soil structure and growing a quality crop.
In western Iowa, Kelly Cunningham operates a dairy that utilizes liquid manure on all of its crop ground without supplementing any acres with commercial fertilizers.
On new ground on which he’s been the first to utilize manure-only nutrient application, he has brought the soil’s organic material up at least 0.5 percent. He thoroughly agitates his lagoons with agitation boats and direct-injects liquid manure using a dragline system. This 0.5 percent increase in organic material may not seem like a big deal, but the increased moisture retention is obvious, he says, especially in dry years.
Near Atwater, California, another dairy owner has been operating an agitation boat for the past year on his lagoons that have limited access points for stationary agitators.
After using strong agitation to move stored solids out of his lagoon last fall, he’s seeing improved crop results on the fields that received that nutrient. Compared to fields on his farm that went without manure, moisture retention between irrigation events is better, and his corn is visibly stronger in a side-by-side comparison.
This past year, before irrigation events, he has been aggressively agitating his final lagoon with an agitation boat to send enriched lagoon water to his crop. Previously, he was utilizing agitation before irrigation, but he didn’t have the ability to quickly bring his entire lagoon into suspension, as much of that lagoon is not accessible from the shore.
The change has been significant with better agitation, and he no longer worries about solids building up in his final cell.
Storage capacity is important in how the dairy utilizes water. Removing settled solids regularly from his final lagoon keeps his flush water clean, his barns clean and his herd healthy.
Liquid manure naturally stratifies in a lagoon, and it takes powerful, aggressive agitation to bring heavier solids into suspension, especially sand.
Traditionally, agitation units are placed along the edge of a pond or storage unit, and liquid is moved horizontally for agitation. These units will keep a zone of about 80 feet in suspension. Around the edges of this area of influence, liquid velocities slow and solids settle out of suspension in mounds.
Storing solids year after year places unnecessary stress on the farm. Sure, the nutrients aren’t being fully utilized, but each year storage capacity becomes less. It’s harder to manage water, and as the situation becomes more extreme, irrigation units start plugging, odor issues rise and herd health declines.
Then, the farm faces a lagoon clean-out. Handling years of stored nutrient in a single event can be expensive, messy and may require more land than what’s available for the high loads of phosphorous.
Pumps must have high flow to maintain high liquid velocities that keep solids in suspension. For adequate agitation, the pump must be able to access the center and all edges of the storage.
Especially for large-scale lagoons, mobile, remote-controlled, floating agitation units, such as an agitation boat, have the capabilities to easily move around to address all parts of the lagoon.
Floating pump units can agitate vertically through the lagoon profile, blasting top water directly down at settled solids to bring them into suspension. The goal with good agitation is to provide complete yearly clean-out and a homogeneous nutrient for land-application.
If the manure isn’t consistent and predictable, it’s not worth much; there is too big of a risk of nutrient under-application and missing the opportunity for full crop production.
If the dairy is growing much of its own feed, this can turn into a vicious cycle of too little fertilizer on the field, yielding too little nutrient for feed, lowering nutrient in the manure further and so on, requiring the dairy to import feed or fertilizer or both onto the farm to break the cycle.
Good, effective, energy-efficient agitation is the key to maximizing the nutrient value of liquid manure.
Agitation can be expensive. How can you decrease costs of agitation? Identify the total time agitation is needed for the pump-out. Will 40,000 gallons per hour be hauled to the field, or 160,000 gallons per hour be pumped to the field through a pipeline or dragline?
How many agitation units are required to bring the lagoon into suspension? What is their fuel cost hourly and how effective are they? Are your current methods and costs achieving your goals?
Very good agitation allows for consistent application throughout the field as a valuable fertilizer. The natural characteristics of manure allow for a slow release of nitrogen that continues to be available in subsequent years.
Building organic material, biological activity and soil structure often happens in the first several years of manure application, with noticeable and positive results. Water retention in the soil increases, leaching and run-off decrease, and when applied correctly, yields thrive.
By emptying lagoons annually or semiannually before a growing cycle, nutrients can be delivered to the fields regularly and predictably.
Unless there are large changes in feed, bedding practices, scale or manure treatment, the content of the manure should be similar during each pump-out event, and management is predictable. Avoiding build-up issues through good agitation can make the whole farm run better.
Continue to use manure as a nutrient and find ways to minimize handling costs for the best financial return. PD
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Showing posts with label Agitation. Show all posts
Showing posts with label Agitation. Show all posts
Saturday, September 28, 2013
Well-agitated liquid manure yields benefits one crop to next
Wednesday, November 14, 2012
Lagoon Agitation - Comparing Fuel Efficiencies
Question:
Do you have any numbers for the fuel savings from using an agitation boat vs. multiple agitators on a larger manure storage?
Answer:
Do you have any numbers for the fuel savings from using an agitation boat vs. multiple agitators on a larger manure storage?
Answer:
Yes, what we find is significant fuel savings, and a much better clean-out for the time available to pump-out the lagoon.
In Detail:
Let's define "larger manure storage" as a 15 million gallon site or larger where it is common for 3 lagoon agitation pumps to be used (the long-reach models that are backed in, and then moved around during the pump out).
We'll do a comparison with the PCE Agitation Boat, model 2067-C. This unit has a 275 horsepower, Tier 3 emission engine direct coupled to a Cornell 6NHTB-17 Pump (17 inch impeller with cutter blades). This is the most popular, commonly sold boat right now. It is a 75% efficient pump where it's designed to run it in it's pump curve, and can move up to 4,000 gallons per minute at that efficiency. We will average the constant flow through the pump at 3,500 gpm. See Pump Curve at the bottom.
So most of the fuel savings is found in operating 1 engine instead of 3, but we can estimate further when we examine the models of lagoon pumps. These pumps are open-faced impeller pumps allowing them to deal very well with trash, but only allows their efficiency to be about 20%. I haven't found online data on this, but a verbal quote from a dealer was 17-19% efficient. If you look at various models of lagoon pumps and choose the best and biggest out there for the large pits (which is what you'll need), we find a large range of horsepower requirements to be 160-240 hp.
How long will we run these pumps? We can estimate the time required for agitation by taking the total gallons available and dividing by the flow rate of the pump to find total hours of agitation needed to turn the pit once. We estimate "turning it" 3 times for good agitation. During most of this time we are pumping to the field, so we won't be agitating the full amount 3 times, but we will use 3 for the ease of math. The quality of agitation should be tested with samples to see what is really happening, but we have found a multiple of 3 to be sufficient for planning purposes. Of course, you have to use good practice not to pump all the water off the top before agitation, so starting agitation before pump-out is still important.
15,000,000 gallons / 3,500 GPM / 60 minutes = 71.4 hours x 3 turns = 214.3 hours / 12 hrs per day = 17.9 days
The limiting time factor will often be in relation to the system pumping to the field. As an example, a line running at 2,000 gallons per minute for 7 hours a day (understanding that sets have to change and there is down-time on the pump-out system while the agitators are still running).
15,000,000 gallons / 2,000 GPM (to the field) / 60 min = 125 hours / 7 hrs per day = 17.9 days
FUEL:
PCE Boats are set up to run between 1600-1770 RPM. The JD engine we use, says it consumes 0.35 lb/hp-hr at 1600 -1800 RPM, and creates the necessary horsepower at this RPM. See Engine Spec
With a PCE Agitation Boat, to move on average 3,500 gallons per minute, the 6NHTB-17 pump requires 220 hp. There are about 7 pounds of diesel fuel in a gallon, so 220 hp x .34 lb/hp-hr / 7 lbs = 10.7 gallons per hour.
To generalize fuel consumption across all engines, a field guideline is: 1 gallon of diesel fuel produces about 22 horsepower. ( 220 / 22 = 10 gallons per hour. ) We'll use this rule to allow for differences in tractors and engines running lagoon pumps for our comparison purposes.
Lagoon Pumps ask for 1,000 RPM and 160 hp - 240 hp.
160 / 22 = 7.3 gallons per hour
240 / 22 = 10.9 gallons per hour
With 3 Units running:
7.3 x 3 = 21.9 gallons per hour
10.9 x 3 =32.7 gallons per hour
TIME Allowed: 214.3 hours
21.9 x 214.3 = 4,693 gallons for three 160 hp engines
32.7 x 214.3 = 7,008 gallons for three 240 hp engines
10.7 x 214.3 = 2,293 gallons for a PCE 2067-C Boat
COST @ $3.50 per gallon:
4,693 gallons = $16,425.50
7,008 gallons = $24,528.00
2,293 gallons = $8,025.50
In our custom pumping operation, we find a range of 10-16 gallons per hour for each lagoon pump. The fuel consumption depends on the tractor you are using to run the pump. We also find the boat needing only 5-8 gallons per hour, but averaging closer to 6 to produce the results we want.
3 Tractors running pumps:
13 gallons per hour x 3 engines x 214.3 hours x $3.50 = $29,252
PCE 2067-C Agitation Boat:
6 gallons per hour x 1 engine x 214.3 hours x $3.50 = $4,500
Conclusion:
In theory, at a large site of 15 million gallons or more, in comparison to running 3 lagoon pumps with 160 hp engines, the PCE Agitation Boat is twice as fuel efficient.
In our operation, at large sites of 15 million gallons or more the boat can be up to 6.5 times more fuel efficient than running lagoon pumps.
Pumps are all designed uniquely to achieve different results. This comparison is for agitation purposes at a large outdoor lagoon site. The pumps compared do not have all the same features or fill all the same needs.
In Detail:
Let's define "larger manure storage" as a 15 million gallon site or larger where it is common for 3 lagoon agitation pumps to be used (the long-reach models that are backed in, and then moved around during the pump out).
We'll do a comparison with the PCE Agitation Boat, model 2067-C. This unit has a 275 horsepower, Tier 3 emission engine direct coupled to a Cornell 6NHTB-17 Pump (17 inch impeller with cutter blades). This is the most popular, commonly sold boat right now. It is a 75% efficient pump where it's designed to run it in it's pump curve, and can move up to 4,000 gallons per minute at that efficiency. We will average the constant flow through the pump at 3,500 gpm. See Pump Curve at the bottom.
So most of the fuel savings is found in operating 1 engine instead of 3, but we can estimate further when we examine the models of lagoon pumps. These pumps are open-faced impeller pumps allowing them to deal very well with trash, but only allows their efficiency to be about 20%. I haven't found online data on this, but a verbal quote from a dealer was 17-19% efficient. If you look at various models of lagoon pumps and choose the best and biggest out there for the large pits (which is what you'll need), we find a large range of horsepower requirements to be 160-240 hp.
How long will we run these pumps? We can estimate the time required for agitation by taking the total gallons available and dividing by the flow rate of the pump to find total hours of agitation needed to turn the pit once. We estimate "turning it" 3 times for good agitation. During most of this time we are pumping to the field, so we won't be agitating the full amount 3 times, but we will use 3 for the ease of math. The quality of agitation should be tested with samples to see what is really happening, but we have found a multiple of 3 to be sufficient for planning purposes. Of course, you have to use good practice not to pump all the water off the top before agitation, so starting agitation before pump-out is still important.
15,000,000 gallons / 3,500 GPM / 60 minutes = 71.4 hours x 3 turns = 214.3 hours / 12 hrs per day = 17.9 days
The limiting time factor will often be in relation to the system pumping to the field. As an example, a line running at 2,000 gallons per minute for 7 hours a day (understanding that sets have to change and there is down-time on the pump-out system while the agitators are still running).
15,000,000 gallons / 2,000 GPM (to the field) / 60 min = 125 hours / 7 hrs per day = 17.9 days
FUEL:
PCE Boats are set up to run between 1600-1770 RPM. The JD engine we use, says it consumes 0.35 lb/hp-hr at 1600 -1800 RPM, and creates the necessary horsepower at this RPM. See Engine Spec
With a PCE Agitation Boat, to move on average 3,500 gallons per minute, the 6NHTB-17 pump requires 220 hp. There are about 7 pounds of diesel fuel in a gallon, so 220 hp x .34 lb/hp-hr / 7 lbs = 10.7 gallons per hour.
To generalize fuel consumption across all engines, a field guideline is: 1 gallon of diesel fuel produces about 22 horsepower. ( 220 / 22 = 10 gallons per hour. ) We'll use this rule to allow for differences in tractors and engines running lagoon pumps for our comparison purposes.
Lagoon Pumps ask for 1,000 RPM and 160 hp - 240 hp.
160 / 22 = 7.3 gallons per hour
240 / 22 = 10.9 gallons per hour
With 3 Units running:
7.3 x 3 = 21.9 gallons per hour
10.9 x 3 =32.7 gallons per hour
TIME Allowed: 214.3 hours
21.9 x 214.3 = 4,693 gallons for three 160 hp engines
32.7 x 214.3 = 7,008 gallons for three 240 hp engines
10.7 x 214.3 = 2,293 gallons for a PCE 2067-C Boat
COST @ $3.50 per gallon:
4,693 gallons = $16,425.50
7,008 gallons = $24,528.00
2,293 gallons = $8,025.50
In our custom pumping operation, we find a range of 10-16 gallons per hour for each lagoon pump. The fuel consumption depends on the tractor you are using to run the pump. We also find the boat needing only 5-8 gallons per hour, but averaging closer to 6 to produce the results we want.
3 Tractors running pumps:
13 gallons per hour x 3 engines x 214.3 hours x $3.50 = $29,252
PCE 2067-C Agitation Boat:
6 gallons per hour x 1 engine x 214.3 hours x $3.50 = $4,500
- These fuel comparisons also do not take into consideration the effectiveness of the clean out. With a 20% efficient pump next to a 75% efficient pump we could make the conclusion it will take 3.75 times more energy for a less efficient pump to do the same work. However, we would need a pump curve from a lagoon pump to fully draw this conclusion.
- Cost of transport for 3 tractors and lagoon pumps can also be considered in time and fuel VS transport of the agitation boat on a trailer behind a pickup. The fuel storage of the tractors will also require re-fueling the units about 3 times more often.
- Cost of ownership can be considered with average lagoon pumps selling for about $30,000 plus tractor or engine unit ($15,000 min), and the agitation boat selling at about $125,000. The boat just about pays for itself in fuel savings for some operators.
Conclusion:
In theory, at a large site of 15 million gallons or more, in comparison to running 3 lagoon pumps with 160 hp engines, the PCE Agitation Boat is twice as fuel efficient.
In our operation, at large sites of 15 million gallons or more the boat can be up to 6.5 times more fuel efficient than running lagoon pumps.
Pumps are all designed uniquely to achieve different results. This comparison is for agitation purposes at a large outdoor lagoon site. The pumps compared do not have all the same features or fill all the same needs.
Friday, September 9, 2011
Agitation Boat - Front Cannon!
Last week, I was fortunate enough to travel north with Dad to South Dakota and Minnesota. We visited two pumping sites in South Dakota that were running PCE Agitation Boats on dairy lagoons.
The first dairy we visited was being pumped by Precision Pumping, Inc. of Minnesota. They have an early model of BOAT 2067 with a Cornell Redi-Prime® Pump. We delivered a front nozzle attachment for the "cannon" - the Gate 3 outflow above water. This outflow can be used to sink solids floating on the top, to wash down the banks, or to deliver fluid through a hose (if the boat is anchored to shore).
Upon arrival at the lagoon, there was 12"-18" of crust on the top of the lagoon, with 2 lagoon pumps agitating - one at each end.
 |
| Lagoon Condition BEFORE Boat Agitation |
 |
| Using the Agitation Boat as stationary agitation against a bank |
See another video of this at: http://www.malechainc.com/blog.html
With the control to individually open & shut 3 different outflow gates, you have a lot of control over agitation. The gates can be utilized to control the amount of flow through each agitation nozzle by only partially opening or closing a gate. Throughout the video, you can see variations in flow out the front cannon as the other gates are opened or closed.
Friday, July 1, 2011
Agitation Boat: On the Trailer
Mr. David Stephens of Missiouri has one of the first PCE boats - a prototype model PCE built for him last fall. We really enjoy his creativity when it comes to putting it to use in various situations. He recently sent a few pictures detailing his use.
Below are pictures of using the boat on its trailer to transfer liquid from a concrete structure to a lagoon.
He laid out about 100' of 5" hose and 70' of 6" hose. The flow was restricted some by 4" discharge straws on the ends. MobileStar Pic shows 2580 GPM at 1425 RPM.
He laid out about 100' of 5" hose and 70' of 6" hose. The flow was restricted some by 4" discharge straws on the ends. MobileStar Pic shows 2580 GPM at 1425 RPM.
At another site David set the boat up similar to a PCE agitation trailer.
He writes, "Got things set up and put the boat to use stirring the pit. As you can see from
1st pic we were in dire need of this. Pit was completely full and nothing but solids. When done pit was nothing but good lagoon water. Pits are only a short 4' deep."
.
For more information on agitating deep pits with PCE pumps:
http://www.puckenterprises.com/AgitationTrailersPage.html
One of the biggest drawbacks to utilizing the Boat in this fashion is the pump's height off the ground. A PCE Self Prime Trailer sits much lower adding to the depth that it can reach. With a 4 foot deep pit, this was not an issue for David.
David Stephens is a custom applicator in Missouri.
Wednesday, June 15, 2011
Nancy's Equation of the Day
This past year has been pretty exciting. When Dad told me last fall they were seeing flow rates of 2,000 GPM, I thought wow, that's pretty good! Immediately I went to the old standard of 1¢ per gallon - and said what? $20 per minute? Dad gave me a smile, shrug and said not bad for a manure hauler huh? I started asking more questions - well how much does this cost? how much does that cost? Trying to figure out exactly how well those drag hose systems were cash flowing, but he cut me off, and I let it be. I'm sure you've all done the math on your systems already, and those of you who attended pump school this spring and called us back with 400 GPM increases from your same line have really seen the return.
Today's Equation of the Day - Expected Fuel Savings by operating a PCE Agitation Boat
Fact #1 - Outdoor Lagoons must be agitated or they will fill up with solids and cause lots of trouble.
Fact #2 - The industry standard: Lagoon Pumps
Estimation #1 - Cost of Fuel Per Day to Operate 1 Lagoon Pump:
6 hours x 10 Gal/Hr x $3.50 diesel Fuel = $210 per day
Estimation #2 - Days per year in Operation:
4 months x 19 days = 76 days
Estimated Fuel Cost Per Year for:
1 Lagoon Pump: $15,960
2 Lagoon Pumps: $31,920
3 Lagoon Pumps: $47,880
PCE Agitation Boat 1045 (small boat) has shown performance to replace up to 3 lagoon pumps.
Estimation #1 - Fuel Cost per day to operate 1 PCE Agitation Boat:
6 hours x 2 gal/Hr x $3.50 diesel fuel = $42 per day
Estimation #2 - Days per year in Operation:
4 months x 19 days = 76 days
Estimated Fuel Cost Per Year for:
BOAT 1045: $3,192
Estimated Fuel SAVINGS per Year by Operating a PCE Boat vs. Lagoon Pumps
1 Lagoon Pump: $12,768 fuel savings
2 Lagoon Pumps: $28,728 fuel savings
3 Lagoon Pumps: $44,688 fuel savings
These are my estimations and only part of the bigger picture when it comes to transportation time and costs, the number of people who need to be at the site, and the quality of their work environment.
Call or write for details!
Today's Equation of the Day - Expected Fuel Savings by operating a PCE Agitation Boat
Fact #1 - Outdoor Lagoons must be agitated or they will fill up with solids and cause lots of trouble.
Fact #2 - The industry standard: Lagoon Pumps
Estimation #1 - Cost of Fuel Per Day to Operate 1 Lagoon Pump:
6 hours x 10 Gal/Hr x $3.50 diesel Fuel = $210 per day
Estimation #2 - Days per year in Operation:
4 months x 19 days = 76 days
Estimated Fuel Cost Per Year for:
1 Lagoon Pump: $15,960
2 Lagoon Pumps: $31,920
3 Lagoon Pumps: $47,880
PCE Agitation Boat 1045 (small boat) has shown performance to replace up to 3 lagoon pumps.
Estimation #1 - Fuel Cost per day to operate 1 PCE Agitation Boat:
6 hours x 2 gal/Hr x $3.50 diesel fuel = $42 per day
Estimation #2 - Days per year in Operation:
4 months x 19 days = 76 days
Estimated Fuel Cost Per Year for:
BOAT 1045: $3,192
Estimated Fuel SAVINGS per Year by Operating a PCE Boat vs. Lagoon Pumps
1 Lagoon Pump: $12,768 fuel savings
2 Lagoon Pumps: $28,728 fuel savings
3 Lagoon Pumps: $44,688 fuel savings
These are my estimations and only part of the bigger picture when it comes to transportation time and costs, the number of people who need to be at the site, and the quality of their work environment.
Call or write for details!
Tuesday, April 26, 2011
PCE Small Boat in Cement Lagoon
I went to visit Jason Arp at a hog site north of Dunlap, IA yesterday. The weather has been very rainy and overcast in this area the past few weeks, but we finally saw some sun over the weekend. I caught some footage of PCE's small boat that Jason was running in a cement lagoon....until it once again started raining:
PCE agitation boats are fully remote controlled. Start, Stop, Throttle, Steering. This small model was designed with this purpose in mind - for use in cement lagoons. It had to be light enough to easily lift in and out of the lagoon, and very well balanced so it was easy to handle. Jason was pretty nervous handling the boat like this for the first time, but said it went really well and he even agreed to let me come video the process next week at another cement lagoon.
He's been agitating this pit for the last several years with two lagoon pumps that he would move around the pit to really work it up - but he still knew they were leaving piles of solids on the bottom that those pumps just wouldn't reach. Not long after placing the boat yesterday did they see the solids boiling off the bottom. They just couldn't believe it. Pretty soon the boat wasn't moving quite as fast. As he was driving the boat around the lagoon it would drag a bit over piles of solids, and slow down as it was trying to push solids that were floating. He's pretty sure it will take another year before they really get this lagoon cleaned out - that's a lot of solids!
A confession - I'm a bit of a wuss, I really hate standing at lagoon sites when they are being agitated. You all know why. It stinks. Yesterday I was really surprised at how much better it was to tolerate. The boat isn't sending any liquid into the air, and I think it really helps.
I'm working up more of the video from yesterday. It will be on YouTube soon, and also on the Agitation Boat -Video page of our website.
Please post questions and responses - I'll pester Dad for answers, and those of you with boats, we'd love to hear how they are working - good and bad!
Nancy
PCE agitation boats are fully remote controlled. Start, Stop, Throttle, Steering. This small model was designed with this purpose in mind - for use in cement lagoons. It had to be light enough to easily lift in and out of the lagoon, and very well balanced so it was easy to handle. Jason was pretty nervous handling the boat like this for the first time, but said it went really well and he even agreed to let me come video the process next week at another cement lagoon.
He's been agitating this pit for the last several years with two lagoon pumps that he would move around the pit to really work it up - but he still knew they were leaving piles of solids on the bottom that those pumps just wouldn't reach. Not long after placing the boat yesterday did they see the solids boiling off the bottom. They just couldn't believe it. Pretty soon the boat wasn't moving quite as fast. As he was driving the boat around the lagoon it would drag a bit over piles of solids, and slow down as it was trying to push solids that were floating. He's pretty sure it will take another year before they really get this lagoon cleaned out - that's a lot of solids!
A confession - I'm a bit of a wuss, I really hate standing at lagoon sites when they are being agitated. You all know why. It stinks. Yesterday I was really surprised at how much better it was to tolerate. The boat isn't sending any liquid into the air, and I think it really helps.
I'm working up more of the video from yesterday. It will be on YouTube soon, and also on the Agitation Boat -Video page of our website.
Please post questions and responses - I'll pester Dad for answers, and those of you with boats, we'd love to hear how they are working - good and bad!
Nancy
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